Category: 8. Health

  • Your eyes can alert you to dementia onset 12 years in advance

    Your eyes can alert you to dementia onset 12 years in advance

    Your eyes do more than show your brain what’s happening in the world around you. They also reveal how well your brain may fare in the years ahead, including whether or not you might develop dementia.

    A long‑running study of 8,623 adults has found that a subtle slowdown in detecting a faint triangle on a computer screen can hint at Alzheimer’s disease up to 12  years before diagnosis.


    Lead author Eef Hogervorst of Loughborough University says the simple test “could slot into routine checkups without adding a single drop of blood.”

    Vision timing signals brain trouble

    Participants pressed a button when they spotted a triangle drifting amid random dots. Those who later developed dementia needed roughly two extra seconds – a gap large enough to raise their future risk by 56 percent. 

    The task measures visual processing speed, the time the brain takes to register and respond to a stimulus. Sluggish scores predicted dementia even after researchers adjusted for age, education, and cardiovascular health.

    “Visual sensitivity is related to memory performance,” noted Hogervorst. She adds that eyesight often declines quietly, leaving people unaware until memory falters.

    A similar pattern appeared in an independent analysis showing that early amyloid plaques disrupt visual signals before memory centers suffer. Taken together, the findings suggest eye‑based tests could extend the warning window for preventive care.

    Eyes offer dementia warning

    The retina is an outgrowth of the brain, so toxic proteins can accumulate there first. Researchers now examine retinal layers for thinning, abnormal blood vessels, and microscopic deposits that mirror cerebral changes.

    Damage often begins in the occipital cortex, the region that deciphers vision, before spreading to the hippocampus. That makes contrast sensitivity, color discrimination, and motion detection early casualties.

    People with Alzheimer’s also struggle to ignore distractions. “These problems could increase the risk of driving accidents,” warned Thom Wilcockson, a psychologist at Loughborough University.

    Eye-tracking research confirms the concern, showing that older drivers with dementia exhibit erratic saccades, longer fixations, and reduced scanning range – all linked to crash risk.

    What slowing detection really means

    Spotting a shape on a screen sounds trivial, yet it taps fast neural circuits shared with memory. When those circuits lag, forgetting names and appointments may follow.

    The Norfolk data showed the triangle test remained significant after standard memory exams were considered. In clinics, combining both could improve accuracy while saving time and cost.

    Slower vision also correlates with trouble recognizing faces, a social cue often missed in early dementia. Patients skim past eyes and mouths, failing to “imprint” new acquaintances and later feeling lost in familiar rooms.

    Several groups are testing whether directed eye exercises can sharpen recall. Early trials of rapid left‑right movements report modest gains, though results remain mixed.

    Smartphones join dementia fight

    High‑grade eye trackers once cost thousands of dollars. A California team has squeezed similar optics into a smartphone app that uses the front‑facing infrared camera to measure pupil changes.

    The prototype walks users through a brief pupil dilation task, then uploads data for cloud analysis. Engineers hope the approach will let families monitor brain health between clinic visits.

    Consumer wearables are also inching closer. Some virtual‑reality headsets already track gaze direction at millisecond resolution, offering another route for large‑scale screening.

    Still, technology alone is not enough. Experts stress the need for clear guidelines to avoid false alarms and protect privacy.

    Fight dementia with eye health

    Lifestyle counts, too. A 14‑year study of almost 2,000 older adults found those who read at least once a week cut cognitive decline odds by nearly half.

    Reading, watching subtitles, or knitting forces the eyes to dart and refocus, a workout for neural networks. Longer education and regular exercise add extra cognitive reserve, buffering the toll of disease.

    Optometrists recommend annual exams after people reach 60 years of age.

    Reporting new glare, color shifts, or slowed adaptation can nudge physicians to order broader cognitive checks.

    Vision‑friendly habits help, too. Good lighting, high‑contrast text, and blue‑green filters reduce strain and may delay functional loss.

    Finally, keep blood vessels healthy. Controlling blood pressure, diabetes, and cholesterol supports both retinal and cerebral circulation, tying the two organs together.

    The study is published in Scientific Reports.

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  • Acute Myocardial Infarction Due to Spontaneous Coronary Dissection in

    Acute Myocardial Infarction Due to Spontaneous Coronary Dissection in

    Introduction

    Over 33.3% of pregnancy-related deaths are due to cardiovascular diseases, with acute myocardial infarction (AMI) being a significant contributor to maternal mortality.1 While the risk of AMI during pregnancy and the early postpartum period is relatively low (6 to 10 cases per 100,000 pregnancies), it is three times higher compared to non-pregnant women of reproductive age.2,3 Pregnant women who experience AMI have a 22-fold higher in-hospital mortality risk, with a 37% mortality rate and the potential loss of both mother and child.1,4 In the past 20 years, the incidence of AMI in pregnancy has increased, likely due to the rising average maternal age and greater prevalence of risk factors.5,6 The etiology of AMI also differs significantly. In the general population, most cases result from atherosclerotic coronary artery disease. However, among pregnant women, approximately 40% of AMI cases are associated with spontaneous coronary artery dissection (SCAD). Atherosclerosis accounts for around 27% of cases, while myocardial infarction with non-obstructive coronary arteries (MINOCA) represents up to 29%.2,7,8

    The pathophysiology of SCAD remains unclear and likely multifactorial. It involves spontaneous coronary artery dissection due to an intramural hematoma, with or without intimal rupture.7,8 SCAD is often linked to arteriopathies, connective tissue disorders, and autoimmune diseases.8 Pregnant women, especially in the third trimester and postpartum, are at higher risk, particularly those who have undergone infertility treatment, including in vitro fertilisation.9–11

    Case Report

    A 28-year-old female, gravida 3, at 37 weeks of gestation, was admitted to the district central hospital via emergency medical services with complaints of a single episode of vomiting, nausea, constrictive retrosternal pain, and a sensation of rapid heartbeat. She attributed the onset of symptoms to the consumption of a low-alcohol beverage the previous evening (300 mL of light beer) along with potato chips.

    Her medical history revealed a prior smoking habit, with a four-year history of tobacco use, smoking up to 15 cigarettes per day (pack-year index: 3). She discontinued smoking upon conception of the current pregnancy. Her family history was unremarkable for cardiovascular disease, connective tissue disorders, or sudden cardiac death. The patient’s obstetric history included a spontaneous miscarriage at 11 weeks of gestation in 2015. In 2018, she had an uncomplicated full-term pregnancy, resulting in a vaginal delivery of a healthy female neonate weighing 3300 g.

    The emergency medical team administered antispasmodics with minimal effect. The time from the onset of symptoms to hospitalization was 7 hours. An electrocardiogram (ECG) was performed immediately upon arrival (Figure 1, ECG from 24.09.23), showing no signs of acute ischemia. Troponin I was measured at 0.10 ng/mL (normal value: up to 0.16 ng/mL). Routine laboratory tests showed elevated total cholesterol (TC) at 7.03 mmol/L, low-density lipoprotein cholesterol (LDL-C) at 4.70 mmol/L, high-density lipoprotein cholesterol (HDL-C) at 1.48 mmol/L, and triglycerides (TG) at 2.74 mmol/L. These findings were considered physiological for late pregnancy and not indicative of a primary lipid disorder.

    Figure 1 Initial ECG recording taken on admission. No signs of acute ischemia are seen.

    Upon admission, the patient continued to experience recurrent episodes of constricting retrosternal pain. A repeat investigation was performed, revealing a significant rise in troponin I levels, which was 14.31 ng/mL, 4 hours after hospitalization. The repeat ECG (Figure 2, ECG from 24.09.23) showed ST-segment elevation in leads I, aVL, and V4-V6, with reciprocal ST depression in leads II, III, aVF, and negative T-waves in leads I and aVL. Echocardiography demonstrated septal and anterior left ventricular wall hypokinesis with left ventricular ejection fraction of 50%. Given the patient’s clinical symptoms, ECG findings, and the increase in myocardial necrosis markers, along with input from relevant specialists, the decision was made to transfer the patient to a center capable of providing specialized care.

    Figure 2 Follow-up ECG displaying ST-segment elevation and reciprocal changes, indicating acute ischemic injury.

    Thus, the patient was admitted to the intensive care unit of the maternity hospital for further observation and continuous cardio-respiratory monitoring. An ultrasound was immediately performed in the obstetrics department to assess the fetal condition. At the time of admission, the patient did not report any complaints, and the ECG showed no abnormalities. Considering the transient, rapidly evolving changes on the ECG, which were clearly associated with retrosternal pain, and the significant rise in myocardial necrosis markers over time, a presumed diagnosis of acute type 2 myocardial infarction was made.

    A decision was reached to proceed with conservative management, and the patient was started on enoxaparin 0.4 mL twice daily subcutaneously and acetylsalicylic acid (ASA) 100 mg once daily. The following day, the patient again complained of severe retrosternal pain, which did not alleviate despite the administration of nitrates and required opioid analgesics. In response, an echocardiogram was immediately performed, revealing hypokinesis of the anterior segment of the left ventricular wall. The repeat ECG (Figure 3, ECG from 26.09.23) was registered. The aforementioned changes were interpreted as an expansion of AMI, prompting the decision to proceed with urgent coronary angiography to determine the subsequent treatment strategy. During the coronary angiography, a femoral access was used. A long dissection in the mid-distal segment of the left anterior descending artery (LAD) was noted (Figure 4A). Two Resolute Integrity (DES) stent systems were then implanted using the “stent-in-stent” technique. Follow-up angiography showed complete stent deployment in the LAD, with adequate positioning and restoration of the main blood flow through the LAD (TIMI – 3; TIMI myocardial perfusion grade – 3) (Figure 4B). No significant narrowings were identified in the left circumflex artery or the right coronary artery.

    Figure 3 ECG taken during symptom recurrence, revealing expansion of ischemic changes.

    Figure 4 (A) Coronary angiography identifying a long dissection in the left anterior descending artery (arrow). (B) Post-stenting angiography confirming restored blood flow in the affected artery (ellipse).

    Following PCI, clopidogrel (75 mg once daily) and bisoprolol (1.25 mg once daily) were added to the patient’s treatment regimen. Regarding pregnancy management, multiple consultations were held with a multidisciplinary team comprising specialists in obstetrics and cardiology. The patient remained under continuous surveillance in the high-risk obstetric intensive care unit. Given the gestational age of 37–38 weeks and the elevated risk associated with surgical delivery, adjustments were made to the antiplatelet and anticoagulant therapy. Specifically, clopidogrel was discontinued, and enoxaparin was replaced with heparin. Heparin was administered at a dose of 7,000 IU every six hours, with activated partial thromboplastin time monitoring. It was recommended that the final dose be administered no later than four hours before the planned delivery.

    At 39 weeks of gestation, due to the onset of spontaneous labor and rupture of membranes in the presence of a pure breech presentation, a decision was made to proceed with delivery via cesarean section. A female neonate was delivered, weighing 3,300 g and measuring 54 cm in length, with Apgar scores of 8/8. On postoperative day 4, the patient and her newborn were discharged home. Recommendations were provided regarding ongoing pharmacological therapy, specifically the continuation of DAPT (ASA and clopidogrel) for the next 12 months.

    The subsequent follow-up period was uneventful. At 4 months postpartum, her lipid profile had normalized: total cholesterol 4.71 mmol/L, LDL-C 2.9 mmol/L, HDL-C 1.54 mmol/L, and triglycerides 0.93 mmol/L, supporting the interpretation that the earlier elevation was related to physiological gestational changes. One year after myocardial infarction, ECG revealed persistent scarring at the apex extending to the interventricular septum, mild ST-segment elevation, and biphasic T waves in leads V3–V4 (Figure 5, ECG from 11.11.2024). Echocardiography showed a preserved left ventricular ejection fraction. No clinical evidence of a vascular or systemic connective tissue disorder has been observed during the one-year follow-up to date.

    Figure 5 Follow-up ECG one year later, showing residual non-specific ST-T abnormalities.

    Discussion

    Cardiovascular risk factors in pregnancy are consistent with those in the general population, including a family history of cardiovascular disease, dyslipidemia, diabetes, and smoking.12 Pregnancy-specific factors include polycystic ovary syndrome, early menarche, maternal age over 35, gestational diabetes, pre-eclampsia, and hormonal therapy use.13

    Although the patient had ceased smoking during pregnancy, her prior tobacco use may have contributed to vascular vulnerability. Several studies have identified smoking as a potential risk factor for SCAD, both in pregnancy-associated and non-pregnancy cases, likely due to its role in vascular inflammation and endothelial dysfunction. In particular, a meta-analysis of women with SCAD, smoking was among the most frequently reported cardiovascular risk factors, present in nearly a quarter of cases.14 Another study found a significant association between smoking and increased mortality in SCAD patients.15

    Similarly, while gestational hyperlipidemia has been proposed to influence vascular function through mechanisms such as endothelial dysfunction or oxidative stress, its direct role in SCAD remains unproven. SCAD is typically not associated with lipid deposition or coronary atherosclerotic plaque.16 During pregnancy, physiological hyperlipidemia is well recognized: total cholesterol and LDL-C typically rise by 30–50%, triglycerides by 50–100%, and HDL-C by 20–40% as gestation progresses.17 The patient’s third-trimester lipid profile was consistent with these expected changes, and normalization at follow-up supported the interpretation of a transient physiological response. These findings underscore the importance of interpreting lipid values in pregnancy within trimester-specific reference ranges, rather than assuming pathological significance in isolation.

    Pregnancy-related SCAD likely results from increased shear stress, elevated progesterone reducing arterial elasticity, and estrogen-induced hypercoagulation and collagen inhibition. Increased cardiac output and blood volume further contribute. It often affects major coronary arteries, leading to reduced ejection fraction and severe maternal-fetal complications.18–23

    Managing patients with pregnancy-related SCAD is challenging, particularly in diagnosing the condition. In 70% of cases, SCAD presents with typical ST-segment elevation on ECG.24 However, nearly one-third of patients show no ECG signs of coronary circulation impairment.10,25 In the presented clinical case, early ECG showed a transient ST elevation in the anterior-lateral wall, which resolved after pain relief, initially suggesting vasospastic angina. The key indicator of myocardial injury was the sustained rise in troponin I levels. Notably, troponin is preferred over CK-MB in pregnant women, as CK-MB can rise due to uterine contractions or cell breakdown during delivery, with lower specificity in pregnancy and postpartum.26

    Given the absence of pronounced clinical symptoms at the time of our patient’s transfer, a conservative treatment approach was initially chosen. However, this was later reassessed due to the recurrence of symptoms (angina, vomiting), accompanied by deteriorating ECG changes and severe arrhythmias. There is no consensus on the preferred management strategy for pregnant women with AMI, and each case requires an individual approach. Conservative management of SCAD not related to pregnancy has shown better outcomes than in pregnant women and the early postpartum period.9,23,24 In pregnant women with SCAD, coronary interventions were associated with a higher risk of dissection progression and the occurrence of new iatrogenic dissections during the procedure.23–25 Additionally, concern arises over the potential impact of X-ray exposure on the fetus during coronary angiography (CAG). During CAG, the patient’s radiation dose is less than 20 mGy, while the fetal radiation dose is estimated at 0.074 mGy.27 The teratogenic risk to the fetus is minimal for doses below 50 mGy and potentially fatal for doses above 150 mGy, depending on gestational age.28 Therefore, it can be concluded that the radiation dose during coronary angiography is generally safe for most pregnant patients.29 An alternative option is the use of computed tomography coronary angiography, particularly in non-ST elevation myocardial infarction patients, but it may cause delays and is not always effective in detecting small areas of dissection.30 The access route for percutaneous intervention is also crucial. Radial access, as opposed to femoral access, reduces radiation exposure to the fetus, as it avoids direct X-ray exposure, making it more often recommended for pregnant women. Moreover, radial access is associated with a lower risk of complications, such as bleeding.31 However, some studies suggest that femoral access may be more effective for pregnant women with SCAD, as it has been linked to nearly three times fewer iatrogenic dissections compared to radial access.32,33 In our patient, femoral access was used, and no expansion of the dissection zone was observed during the procedure.

    Pharmacological management, particularly dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI), has specific considerations. According to the latest European Society of Cardiology guidelines, clopidogrel is recommended as part of DAPT in pregnant women post-PCI, as it is considered safer than glycoprotein IIb/IIIa inhibitors, due to a lack of data on their use in pregnancy.10 However, there are no clear guidelines on the duration of DAPT during labour for patients at high risk of thrombosis or those with recent intervention. Some studies show positive outcomes, while others report serious side effects from prolonged DAPT use.25 A decision was made to continue long-term DAPT, with a short-term discontinuation of clopidogrel before the planned cesarean section. After discharge, the patient continued DAPT for 12 months with no complications.

    While the case highlights key aspects of diagnosis and management, it also has certain limitations. These are inherent to a single-patient observation. Intravascular ultrasound or optical coherence tomography was not performed, which might have provided more precise characterization of the arterial dissection. Additionally, no further investigations were undertaken to evaluate possible underlying vascular or connective tissue disorders. However, the case reflects real-world clinical complexity, where decisions must often be made based on evolving symptoms and limited diagnostic data.

    Conclusion

    The issue of myocardial infarction during pregnancy involves several aspects, including challenges in emergency diagnosis due to a low index of suspicion among young women without traditional risk factors, as well as the absence of clear, definitive algorithms for selecting a management strategy (conservative/invasive). Additionally, there is uncertainty regarding the volume and duration of anticoagulant and antiplatelet therapy. Since the likelihood of conducting randomized clinical trials among pregnant women is quite limited and problematic, the accumulation of sufficient clinical case reports from real-world practice will, in the future, allow for the formulation of a well-founded expert opinion and evidence-based recommendations for managing this patient cohort.

    Date and Materials Statement

    This is a case report without statistical analysis of the raw medical record data. All medical data involving the patient were documented in the patient’s medical records. If necessary, more detailed imaging data or laboratory data can be provided by the corresponding author upon reasonable request.

    Ethics Statement

    Ethical review and approval were not required for the study involving human participants in accordance with the local legislation and institutional requirements. Written informed consent was obtained from the patient for the publication of any potentially identifiable images or data included in this report.

    Informed Consent for Publication

    The patient agreed to publish her medical data including imaging data and laboratory data, and signed the informed consent.

    Author Contributions

    All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

    Funding

    This study was not supported by any external funds.

    Disclosure

    All the authors declare that they have no conflicts of interest in this medical case report and have not received any financial support.

    References

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    2. Smilowitz NR, Gupta N, Guo Y, et al. Acute myocardial infarction during pregnancy and the puerperium in the United States. Mayo Clin Proc. 2018;93(10):1404–1414. doi:10.1016/j.mayocp.2018.04.019

    3. James AH, Jamison MG, Biswas MS, Brancazio LR, Swamy GK, Myers ER. Acute myocardial infarction in pregnancy: a United States population-based study. Circulation. 2006;113(12):1564–1571. doi:10.1161/CIRCULATIONAHA.105.576751

    4. Burlingame J, Horiuchi B, Ohana P, Onaka A, Sauvage LM. The contribution of heart disease to pregnancy-related mortality according to the pregnancy mortality surveillance system. J Perinatol. 2012;32(3):163–169. doi:10.1038/jp.2011.74

    5. Balgobin CA, Zhang X, Lima FV, et al. Risk factors and timing of acute myocardial infarction associated with pregnancy: insights from the national inpatient sample. J Am Heart Assoc. 2020;9(21):e016623. doi:10.1161/JAHA.120.016623

    6. Gédéon T, Akl E, D’Souza R, et al. Acute myocardial infarction in pregnancy. Curr Probl Cardiol. 2022;47(11):101327. doi:10.1016/j.cpcardiol.2022.101327

    7. Elkayam U, Jalnapurkar S, Barakkat MN, et al. Pregnancy-associated acute myocardial infarction: a review of contemporary experience in 150 cases between 2006 and 2011. Circulation. 2014;129(16):1695–1702. doi:10.1161/CIRCULATIONAHA.113.002054

    8. Regitz-Zagrosek V, Roos-Hesselink JW, Bauersachs J, et al. ESC scientific document group. 2018 ESC guidelines for the management of cardiovascular diseases during pregnancy. Eur Heart J. 2018;39(34):3165–3241. doi:10.1093/eurheartj/ehy340

    9. Saw J, Humphries K, Aymong E, et al. Spontaneous coronary artery dissection: clinical outcomes and risk of recurrence. J Am Coll Cardiol. 2017;70(9):1148–1158. doi:10.1016/j.jacc.2017.06.053

    10. Lebrun S, Bond RM. Spontaneous coronary artery dissection (SCAD): the underdiagnosed cardiac condition that plagues women. Trends Cardiovasc Med. 2018;28(5):340–345. doi:10.1016/j.tcm.2017.12.004

    11. Zeven K. Pregnancy-associated spontaneous coronary artery dissection in women: a literature review. Curr Ther Res. 2023;98:100697. doi:10.1016/j.curtheres.2023.100697

    12. Kealey A. Coronary artery disease and myocardial infarction in pregnancy: a review of epidemiology, diagnosis, and medical and surgical management. Can J Cardiol. 2010;26(6):185–189. doi:10.1016/s0828-282x(10)70397-4

    13. Nguyen AH, Murrin E, Moyo A, et al. Ischemic heart disease in pregnancy: a practical approach to management. Am J Obstet Gynecol MFM. 2024;6(3):101295. doi:10.1016/j.ajogmf.2024.101295

    14. Apostolović S, Ignjatović A, Stanojević D, et al. Spontaneous coronary artery dissection in women in the generative period: clinical characteristics, treatment, and outcome-a systematic review and meta-analysis. Front Cardiovasc Med. 2024;11:1277604. doi:10.3389/fcvm.2024.1277604

    15. Adams C, He M, Hughes I, Singh K. Mortality in spontaneous coronary artery dissection: a systematic review and meta-analysis. Catheter Cardiovasc Interv. 2021;98(7):1211–1220. doi:10.1002/ccd.29488

    16. Stanojevic D, Apostolovic S, Kostic T, et al. A review of the risk and precipitating factors for spontaneous coronary artery dissection. Front Cardiovasc Med. 2023;10:1273301. doi:10.3389/fcvm.2023.1273301

    17. Mulder JWCM, Kusters DM, Roeters van Lennep JE, Hutten BA. Lipid metabolism during pregnancy: consequences for mother and child. Curr Opin Lipidol. 2024;35(3):133–140. doi:10.1097/MOL.0000000000000927

    18. Maas AHEM, Bouatia-Naji N, Persu A, Adlam D. Spontaneous coronary artery dissections and fibromuscular dysplasia: current insights on pathophysiology, sex and gender. Int J Cardiol. 2019;286:220–225. doi:10.1016/j.ijcard.2018.11.023

    19. Yip A, Saw J. Spontaneous coronary artery dissection – a review. Cardiovasc Diagn Ther. 2015;5(1):37–48. doi:10.3978/j.issn.2223-3652.2015.01.08

    20. Giacoppo D, Capodanno D, Dangas G, Tamburino C. Spontaneous coronary artery dissection. Int J Cardiol. 2014;175(1):8–20. doi:10.1016/j.ijcard.2014.04.178

    21. Vijayaraghavan R, Verma S, Gupta N, Saw J. Pregnancy-related spontaneous coronary artery dissection. Circulation. 2014;130(21):1915–1920. doi:10.1161/CIRCULATIONAHA.114.011422

    22. Abbott JD, Curtis JP, Murad K, et al. Spontaneous coronary artery dissection in a woman receiving 5-fluorouracil: a case report. Angiology. 2003;54(6):721–724. doi:10.1177/000331970305400613

    23. Havakuk O, Goland S, Mehra A, Elkayam U. Pregnancy and the risk of spontaneous coronary artery dissection: an analysis of 120 contemporary cases. Circ Cardiovasc Interv. 2017;10(3):e004941. doi:10.1161/CIRCINTERVENTIONS.117.004941

    24. Tweet MS, Hayes SN, Codsi E, Gulati R, Rose CH, Best PJM. Spontaneous coronary artery dissection associated with pregnancy. J Am Coll Cardiol. 2017;70(4):426–435. doi:10.1016/j.jacc.2017.05.055

    25. Lindor RA, Tweet MS, Goyal KA, et al. Emergency department presentation of patients with spontaneous coronary artery dissection. J Emerg Med. 2017;52(3):286–291. doi:10.1016/j.jemermed.2016.09.005

    26. Siromakha SO, Arvanytakvy SS, Rudenko SA, Lazorishenetc VV. Coronary insufficiency during pregnancy. Epidemiology, methods of diagnosis and treatment. Ukr J Perinatol Pediatr. 2019;3:32–39. doi:10.15574/PP.2019.79.32

    27. Colletti PM, Lee KH, Elkayam U. Cardiovascular imaging of the pregnant patient. Am J Roentgenol. 2013;200(3):515–521. doi:10.2214/AJR.12.9864

    28. Kuba K, Wolfe D, Schoenfeld AH, Bortnick AE. Percutaneous coronary intervention in pregnancy: modeling of the fetal absorbed dose. Case Rep Obstet Gynecol. 2019;2019:8410203. doi:10.1155/2019/8410203

    29. Alameh A, Jabri A, Aleyadeh W, et al. Pregnancy-associated myocardial infarction: a review of current practices and guidelines. Curr Cardiol Rep. 2021;23:142. doi:10.1007/s11886-021-01579-z

    30. Joshi FR. CT rather than invasive angiography for pregnant patients with NSTEMI?: More delay and more radiation. J Am Coll Cardiol. 2016;68(24):2716–2717. doi:10.1016/j.jacc.2016.08.075

    31. Prokšelj K, Brida M. Cardiovascular imaging in pregnancy. Int J Cardiol Congenit Heart Dis. 2021;5(Suppl. 1):100235. doi:10.1016/j.ijcchd.2021.100235

    32. Prakash R, Starovoytov A, Heydari M, Mancini GB, Saw J. Catheter-induced iatrogenic coronary artery dissection in patients with spontaneous coronary artery dissection. JACC: Cardiovasc Interv. 2016;9(17):1851–1853. doi:10.1016/j.jcin.2016.06.026

    33. Hayes SN, Kim ESH, Saw J, et al. Spontaneous coronary artery dissection: current state of the science: a scientific statement from the American heart association. Circulation. 2018;137(19):e523–e557. doi:10.1161/CIR.0000000000000564

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  • Salmonella cases are at ten-year high in England – here’s what you can do to keep yourself safe

    Salmonella cases are at ten-year high in England – here’s what you can do to keep yourself safe

    Salmonella cases in England are the highest they’ve been in a decade, according to recent UK Health Security Agency (UKHSA) data. There was a 17% increase in cases observed from 2023 to 2024 – culminating in 10,388 detected infections last year. Children and older adults accounted for around a fifth of cases.

    Although the number of infections caused by foodborne diseases such as Salmonella had broadly decreased over the last 25 years, this recent spike suggests a broader issue is at play. A concurrent increase in Campylobacter cases points to a possible common cause that would affect risk of both foodborne pathogens – such as changes in consumer behaviour or food supply chains.

    While the UK maintains a high standard of food safety, any increase in the incidence of pathogens such as Salmonella warrants serious attention.

    Salmonella is a species of bacteria that is one of the most common causes of foodborne illnesses globally. The bacteria causes salmonellosis – an infection that typically causes vomiting and diarrhoea.

    Most cases of salmonellosis don’t require medical intervention. But approximately one in 50 cases results in more serious blood infections. Fortunately, fatalities from Salmonella infections in the UK are extremely rare – occurring in approximately 0.2% of all reported infections.

    Salmonella infections are typically contracted from contaminated foods. But a key challenge in controlling Salmonella in the food supply chain lies in the diverse range of foods it can contaminate.

    Salmonella is zoonotic, meaning it’s present in animals, including livestock. This allows it to enter the food chain and subsequently cause human disease. This occurs despite substantial efforts within the livestock industry to prevent it from happening – including through regular testing and high welfare practices.

    Salmonella can be present on many retail food products – including raw meat, eggs, unpasteurised milk, vegetables and dried foods (such as nuts and spices). When present, it’s typically at very low contamination levels. This means it doesn’t pose a threat to you if the product is stored and cooked properly.

    Vegetables and leafy greens can also become contaminated with Salmonella through cross-contamination, which may occur from contaminated irrigation water on farms, during processing or during storage at home. As vegetables are often consumed raw, preventing cross-contamination is particularly critical.

    Spike in cases

    It’s premature to draw definitive conclusions regarding the causes of this recent increase in Salmonella cases. But the recent UKHSA report suggests the increase is probably due to many factors.

    Never prepare raw meat next to vegetables you intend to eat without cooking, as cross-contamination can lead to Salmonella.
    kathrinerajalingam/ Shutterstock

    One contributing factor is that diagnostic testing has increased. This means we’re better at detecting cases. This can be viewed as a positive, as robust surveillance is integral to maintaining a safe food supply.

    The UKHSA also suggests that changes in the food supply chain and the way people are cooking and storing their food due to the cost of living crisis could also be influential factors.

    To better understand why Salmonella cases have spiked, it will be important for researchers to conduct more detailed examinations of the specific Salmonella strains responsible for the infections. While Salmonella is commonly perceived as a singular bacterial pathogen, there are actually numerous strains (serotypes).

    DNA sequencing can tell us which of the hundreds of Salmonella serotypes are responsible for human infections. Two serotypes, Salmonella enteritidis and Salmonella Typhimurium, account for most infections in England.

    Although the UKHSA reported an increase in both serotypes in 2024, the data suggests that Salmonella enteritidis has played a more significant role in the observed increase. This particular serotype is predominantly associated with egg contamination.

    Salmonella enteritidis is now relatively rare in UK poultry flocks thanks to vaccination and surveillance programmes that were introduced in the 1980s and 1990s. So the important question here is where these additional S enteritidis infections are originating.

    Although the numbers may seem alarming, what the UKHSA has reported is actually a relatively moderate increase in Salmonella cases. There’s no reason for UK consumers to be alarmed. Still, this data underscores the importance of thoroughly investigating the underlying causes to prevent this short-term increase from evolving into a longer-term trend.

    Staying safe

    The most effective way of lowering your risk of Salmonella involves adherence to the “4 Cs” of food hygiene:

    1. Cleaning

    Thoroughly wash hands before and after handling any foods – especially raw meat. It’s also essential to keep workspaces, knives and utensils clean before, during and after preparing your meal.

    2. Cooking

    The bacteria that causes Salmonella infections can be inactivated when cooked at the right temperature. In general, foods should be cooked to an internal temperature above 65°C – which should be maintained for at least ten minutes. When re-heating food, it should reach 70°C or above for two minutes to kill any bacteria that have grown since it was first cooked.

    3. Chilling

    Raw foods – especially meat and dairy – should always be stored below 5°C as this inhibits Salmonella growth. Leftovers should be cooled quickly and also stored at 5°C or lower.

    4. Cross-contamination

    To prevent Salmonella passing from raw foods to those that are already prepared or can be eaten raw (such as vegetables and fruit), it’s important to wash hands and clean surfaces after handling raw meat, and to use different chopping boards for ready-to-eat foods and raw meat.

    Most Salmonella infections are mild and will go away in a few days on their own. But taking the right steps when storing and preparing your meals can significantly lower your risk of contracting it.

    Continue Reading

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  • Initial community response to a novel spatial repellent for malaria prevention in Busia County, Kenya | Malaria Journal

    Initial community response to a novel spatial repellent for malaria prevention in Busia County, Kenya | Malaria Journal

    A total of 60 interviews were completed during the first two rounds of data collection, covering 30 households in each round. The participants included 16 women and 14 men. The mean age of the participants was 49 years (range 35–65), with women averaging 44 years (range 35–55) and men 55 years (range 45–65).

    In addition to commenting on perceived efficacy, perceived reduction in malaria cases, and side effects, participants compared the perceived performance of SR with other mosquito control methods they commonly used such as bednets, mosquito coils and burning leaves. The participants also discussed their communication with others about the product and suggested future improvements.

    Perceived efficacy and early acceptability

    In interviews conducted one week after initial installation, most participants reported that they noticed a reduction in mosquito density and attributed this reduction to the SR’s dawa [the power or strength of the insecticide]. Those who observed mosquitoes in the house reported that they appeared sluggish, biting and flying less aggressively than they did in the past.

    Generally, since you installed these products inside here, I have seen the mosquito population completely reduced. I can say by 99%. Previously, approximately around 7:00 p.m. while seated here [pointing at the sofa set], we would be bitten by mosquitos until when we went to sleep at 9:00 pm. Now, after the installation of the SR, the few mosquitos we see seem sluggish, often flying slowly, and even falling on their own. Additionally, since the installation, I haven’t heard any child complaining about feeling sick.” (Male, age 39, 1-week post-installation).

    In the second interview, 2 months after the initial installation, some participants reported that mosquitoes had returned. They attributed this return to the belief that replacement SRs had less dawa than the initial product and lost their effectiveness after 2–3 weeks.

    How come we are now seeing signs of mosquitos, yet we were praising this product? We are requesting they improve in putting a lot of repellent so that mosquitos do not appear and later disappear. I want, if the product has been installed to repel mosquitos, let it repel mosquitos.” (Male, age 41, 2-month post-installation).

    Some participants also mentioned seasonality, suggesting that the increase in mosquito frequency coincided with millet flowering or the decrease in recent hot weather. One proposed that installing the product during a peak mosquito season could have offered a clearer assessment of its effectiveness.

    While most of the comments focused on mosquito density, some respondents added that fewer family members, particularly children, were falling ill with malaria.

    Since these products were installed in our houses, I have noticed that the number of mosquitos have decreased, and the level of malaria has also decreased. Because before installation, my youngest child had malaria every month, she used to be admitted to the ward. However, since these products were installed, she has never has never been sick.” (Female, age 28, 2-month post-installation).

    In addition to reporting perceived reductions in mosquitoes and malaria symptoms, many participants expressed satisfaction with the SR. They described it as convenient, easy to use, and preferable to other mosquito control tools like nets or coils. These early expressions of acceptance suggest a positive initial reception of the product.

    Comparison of SRs to other mosquito control products

    The participants reported using other products and practices to keep away mosquitoes, including ITNs, mosquito coils, mosquito mats, and burning leaves to produce smoke that repels mosquitoes.

    When asked to compare the SR to other products, respondents cited various factors including the place of protection, the cost, the product’s perceived effectiveness, and the feasibility of installation. Some mentioned that ITNs only protected them while they were sleeping whereas the SRs also offered protection when they were awake. Others reported that SRs obviated the need for ITNs.

    I can say that the SR is better than a net because a net is only used when you go to sleep. You only protect yourself with it during sleep. But with the SR, you can be protected while sitting in the evening. Mosquitoes won’t bother me because of the SR. However, with a net, you must wait until you go to sleep at 10:00 p.m to be protected.” (Female, age 32, 1-week post-installation).

    Because they have installed a product for me that repels mosquitos, I do not see the need to struggle hanging the net because it brings heat. You know during dry season like this there is a lot of heat. There is no need to interfere with the product that repels mosquitos, why not sleep comfortably?” (Male, age 41, 2-month post-installation).

    The respondents also stated that the SR was less labour-intensive than an ITN and that ITNs could tear, make their living spaces hotter, and cause irritation for those who came into direct contact with them.

    It’s our first time to use spatial repellant, and we are still observing the effects. But within this short time, I see it’s effective and it’s chasing away the mosquitoes even while inside the net, the treated net may lose its effectiveness with time, then the mosquitoes just gain access to you.” (Male, age 63, 1-week post-installation).

    Some added that SRs improved household finances since the study provided them at no cost.

    The spatial repellent is good because since they were installed in my house, I do not use any money by going to buy other mosquito repellents. But when I did not have [SR], mosquito coils used to cost me money. When you budget for supper, you must put the mosquito coil budget there too.” (Female, age 28, 1-week post-installation).

    Perceived side effects

    While most respondents reported no side effects within their own households, some mentioned observing effects on non-target organisms, including insects such as cockroaches and small animals. One participant described seeing cockroaches that appeared weakened or dead after installation of the SR:

    What I have experienced with the cockroaches in this house, you find them moving and are weak and some are even dead and others are unconscious there. They are not moving as they used to before and hiding in private places. Currently this product is also affecting them too.” (Female, age 38, 2-month post installation).

    Many viewed these effects as an additional benefit of SRs. Some, however, cited conversations in which a neighbor had mentioned side effects such as children sneezing when they got too close to the product or skin irritation experienced by one participant’s husband after touching it. Others expressed uncertainty about whether the effects experienced since installation were directly caused by the SR or by other factors. As a precaution, some participants reported keeping children at a distance from the product to avoid potential adverse effects. Those ‘Ikee’ [Ateso word for medicine or active ingredient, referring to the SR] you are not supposed to get close. At times when you are putting things in order, you need to keep distance from the ‘Ikee’ because we were advised that way. There was a time when my brother’s child who stays here, he got closer to the ‘Ikee’, he started sneezing and I told him that he is not allowed to be close.” (Female, age 41, 2-month post installation).

    Suggestions for future improvement

    At the first TIPs visit, the participants suggested few improvements to the SR, possibly due to their limited experience. Subsequently informants suggested changes in size, shape, colour, smell, installation method, and replacement frequency. A participant suggested alternating the SR’s colour with each replacement not due to aesthetic preference, but to make it easier to recognize whether the product has been changed especially when residents were away during installation.

    Other mentioned that white was best because it was visible and matched house décor, while a few said colour did not matter as long as the product worked. Regarding shape and size, some participants suggested enlarging SRs could reduce the number of units required per household. They said they liked that the product was odourless and its general appearance but recommended extending installations to areas such as bathrooms, latrines, and schools where mosquito encounters were common, particularly during the early morning.

    Then secondly, there are those places these products were not installed. Places like the toilet. If you can find those, then you install. You know you go there anytime, it is dark, and you get bitten. Then again, within here in our home, children study in school. Our children always leave early. Exactly by 6:00 a.m. they are in class. They can get bitten by mosquitoes while there. If it is possible, they should take [SRs] to schools too.” (Male, 39, 2-month post-installation).

    The participants expressed concerns about the product falling off the wall when installed with tape, which led one family to rehang a fallen product with a nail. They stated their preference for hooks, which kept SRs more securely attached to the wall (Figs. 2 and 3). Some suggested offering a range of colours (black, white, green, blue, khaki) for the products, with one linking a dark colour to attracting mosquitoes.

    The majority expressed a preference for an odorless product, considering allergies, but a few suggested that some scent was necessary for effective mosquito repellency. A recurring recommendation was to increase the amount or concentration of repellent, with diverse opinions on replacement intervals. Some participants suggested a switch to biodegradable materials to address the environmental concerns associated with plastic sheets.Another one is, we were also saying, they should try and look for a product that is friendly to the environment apart from these papers. At least, even if the project ends and they left the products for us they have not come to collect. At least it should be a material that when you throw, it rots faster.” (Male, age 39, 2-month post installation).

    Fig. 2

    Family rehung fallen taped product with nail

    Fig. 3
    figure 3

    Installation of the MosquitoShield™ with hooks

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  • Bionomics of Anopheles gambiae complex (Diptera: Culicidae) and malaria transmission pattern in a pre-elimination area in South–Western Senegal | Malaria Journal

    Bionomics of Anopheles gambiae complex (Diptera: Culicidae) and malaria transmission pattern in a pre-elimination area in South–Western Senegal | Malaria Journal

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  • Q2 2025 Recap: Endocrinology News and Updates

    Q2 2025 Recap: Endocrinology News and Updates

    HCPLive Endocrinology Q2 2025 Recap

    The second quarter of 2025 brought meaningful developments in endocrinology, from FDA actions to clinical breakthroughs spotlighted at major meetings. Several regulatory milestones signaled progress for patients across the spectrum of endocrine disorders, including expanded access to CGM technology, new formulations for adrenal insufficiency, and a broader treatment label for Cushing’s syndrome.

    Novo Nordisk’s NDA for 25 mg oral semaglutide also marked a potential turning point in obesity care, with the first oral GLP-1 formulation for weight management now under review. Meanwhile, June’s ADA Scientific Sessions capped the quarter with a surge of new data on incretin therapies, obesity drugs, and diabetes technology—many with practice-changing potential.

    Here’s a look back at the most impactful regulatory updates and conference highlights shaping the future of endocrine care.

    Regulatory Updates in Endocrinology

    FDA Clears Dexcom G7 15-Day CGM System

    On April 10, 2025, the FDA cleared Dexcom’s G7 15-day continuous glucose monitoring (CGM) system for adults with diabetes, making it the longest-lasting and most accurate CGM approved in the U.S. Based on clinical data showing a MARD of 8.0%, the G7 15 Day demonstrated excellent accuracy and user satisfaction. According to Dexcom, the system offers features like Apple Watch integration, waterproof sensors, and extended wear with a 12-hour grace period for sensor changes. The company plans to ensure compatibility with insulin pump systems ahead of its US launch in late 2025.

    FDA Approves Label Expansion for Osilodrostat for Cushing’s Syndrome

    On April 16, 2025, the FDA approved Recordati’s sNDA for osilodrostat (Isturisa), expanding its indication to include adults with endogenous Cushing’s syndrome who are not surgical candidates or for whom surgery was not curative. Previously approved only for Cushing’s disease, the broader label is supported by data from the LINC 3 and LINC 4 trials showing sustained cortisol reduction and clinical improvement. According to Recordati, osilodrostat offers a vital option for managing hypercortisolemia and preventing severe complications.

    FDA Accepts NDA Submission for Oral Semaglutide 25 mg

    On May 2, 2025, Novo Nordisk announced the FDA accepted its NDA for a once-daily 25 mg oral formulation of semaglutide for chronic weight management in adults with obesity or overweight and at least one comorbidity. Based on results from the 64-week OASIS 4 trial, the oral semaglutide demonstrated significant weight loss and cardiovascular risk reduction. According to Novo Nordisk, this could become the first oral GLP-1 therapy approved for obesity. If approved, it would expand individualized treatment options beyond injectable formulations. An FDA decision is expected in Q4 2025.

    FDA Approves Hydrocortisone Oral Solution for Adrenal Insufficiency

    On May 28, 2025, the FDA approved Eton Pharmaceuticals’ hydrocortisone oral solution (KHINDIVI) for pediatric patients aged 5 and older with adrenocortical insufficiency, marking the first liquid formulation approved for this use. Designed for accurate, individualized dosing, the 1 mg/mL solution helps patients who have difficulty swallowing pills. According to Eton, this ready-to-use formulation eliminates the need for pill-splitting and supports improved treatment outcomes during childhood development.

    American Diabetes Association

    June 2025 also brought several groundbreaking trials and new updates in diabetes care at the 8th American Diabetes Association Scientific Sessions, which were held in Chicago, Illinois from June 20-23, 2025. With multiple sessions dedicated to late-breaking research, the meeting featured multiple simultaneous publications, including a slew of studies related to incretin therapies. To learn more about the meeting’s top news, check out this trio of articles recapping ADA 2025.

    Diabetes Dialogue

    Diabetes Dialogue: Semaglutide for MASH in ESSENCE Trial, With Arun Sanyal, MD

    In this episode, the hosts discuss new Phase 3 data from the ESSENCE trial showing that once-weekly semaglutide 2.4 mg significantly improved liver outcomes and reduced weight in patients with MASH and stage 2 or 3 fibrosis. They speak with the trial’s lead author about semaglutide’s clinical impact, its potential as a future MASH treatment, and how it compares to the currently approved option, resmetirom.

    Diabetes Dialogue: AACE 2025 Recap

    In this episode, the hosts recap key moments from the 2025 AACE Annual Meeting, covering major plenaries, hands-on tech workshops, and the launch of a new diabetes technology certification program. They spotlight updates on GLP-1 safety, health equity, CGM innovations, and emerging trial data, while reflecting on the future of personalized diabetes care.

    Diabetes Dialogue: Real-World Impact of iLet Bionic Pancreas, With Steven Russell, MD, PhD

    In this episode, the hosts speak with the Chief Medical Officer of Beta Bionics about real-world outcomes from the iLet Bionic Pancreas, an FDA-cleared fully autonomous insulin delivery system requiring no user settings. They highlight its strong A1c-lowering effect, minimal hypoglycemia, and promise for underserved populations and primary care use, including off-label applications in type 2 diabetes.

    Diabetes Dialogue: REDEFINE 1 and REDEFINE 2, with Timothy Garvey, MD, and Melanie Davies, MD

    In this episode recorded at ADA 2025, the hosts break down results from the REDEFINE 1 and 2 trials showing that CagriSema delivered substantial weight loss and glycemic improvements in people with and without type 2 diabetes. They also discuss the drug’s safety, clinical relevance, and future in obesity care with trial investigators, highlighting upcoming studies like REDEFINE 3.

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  • Detection of pathogens within Ixodid ticks collected from domestic cats across the USA | Parasites & Vectors

    Detection of pathogens within Ixodid ticks collected from domestic cats across the USA | Parasites & Vectors

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  • Knowledge and practices of dog and cat owners in Mainland Portugal regarding fleas, flea-borne pathogens, and their management | Parasites & Vectors

    Knowledge and practices of dog and cat owners in Mainland Portugal regarding fleas, flea-borne pathogens, and their management | Parasites & Vectors

    Fleas are among the most important worldwide ectoparasites of dogs and cats. Besides being responsible for causing direct deleterious effects such as anaemia and dermatological problems, they are also responsible for the transmission of numerous pathogens, some of which are zoonotic [30]. In Portugal, flea-borne infections have been reported in both companion animals and humans [10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28], highlighting the importance of public education regarding the measures to be taken to reduce the risk of exposure of dogs, cats, and humans to these ectoparasites and the pathogens they transmit. In the present study, a total of 550 companion animal owners in Mainland Portugal responded to a questionnaire regarding fleas, flea-borne pathogens, and their management: 38.5% were dog owners only, 28.7% were cat owners only, and 32.7% owned both animal species. Dog owners usually represent the largest percentage of participants in surveys conducted in the country [33, 34, 39], a trend that might be related to the fact that dogs are the most common pets in Portugal [9] and globally have greater access to veterinary care [41], which increases the frequency of interactions between dog owners and surveys.

    Women made up 69.9% of the participants, which aligns with findings from previous studies on pet ownership, zoonoses, and parasite control awareness [35,36,37,38,39, 42]. This trend is likely related to a higher level of concern among women for the health and well-being of their pets. The mean age of pet owners who responded to the questionnaire was 40 years, and the majority had a secondary or higher level of education, which is similar to what was observed in other studies [35, 36, 38, 39]; this trend may reflect a greater interest among middle-aged adults and individuals with higher educational qualifications to participate in this kind of KP research studies. Geographically, the majority of participants were based in the Área Metropolitana de Lisboa (AML), whereas Algarve had the lowest response rate. Although the questionnaire was distributed through several veterinary clinics across Mainland Portugal, the number of participating clinics in the Algarve was relatively low, potentially influencing respondent numbers. This distribution pattern is consistent with previous national studies [34], [42] and may reflect regional variations in interest levels or cultural differences in pet care practices and perceptions.

    Few studies have assessed companion animal owners’ level of knowledge regarding fleas and flea-borne pathogens [32, 35]. In a study from Hungary [32], most dog and cat owners were unaware that fleas can harm both animals and humans or that the environment can be a source of infestation, while in a study from Malaysia [35] about 40% of cat owners recognised fleas as pathogen vectors and were aware that infestations can originate from the environment. In addition, more than half of the Malaysian cat owners were also able to identify the size, food source, and movement of the fleas, which could be because most of the responders had previously experienced flea infestations in cats. In this study, over 70% of participants correctly identified the flea’s body colour and movement, while more than half recognised its size and diet, demonstrating a reasonable understanding of flea biology. Companion animal owners also recognised the environment, mainly outdoor spaces, and contact with infested animals as common sources of flea infestations, as well as the fact that fleas may remain active year-round, reflecting their awareness of the flea life cycle. Interestingly, cat-only owners were significantly more aware than the other two owner groups that fleas have a flat body shape, and that indoor environments and humans can also be a source of infestation. In contrast to previous studies [32, 35], most participants recognised fleas as vectors of pathogens affecting both animals and humans, with bites being the most commonly known transmission route. However, as in previous studies, only a few could name the specific etiological agents. Knowledge about pathogen transmission through scratches was significantly higher among cat-only owners. Although the identification of pathogens did not differ among the three groups, cat-only owners most frequently mentioned the etiological agents of cat-scratch disease and mycoplasmosis, while D. caninum was more frequently noted by dog-only and dog+cat owners, suggesting that some participants were able to correctly associate certain pathogens with the animal species they affect.

    In this study, multivariate analysis confirmed trends observed in previous CPP questionnaires regarding sex, age, and education level. Specifically, a higher awareness of fleas and flea-borne pathogens was associated with participants who had higher education, were under 50 years of age (Kf only), and were female (Kp only). Knowledge was also higher among participants living in the AML, Centro, and Algarve regions. Interestingly, despite the low number of participants from the Algarve region, their greater knowledge may be linked to the participation of individuals particularly concerned about the seriousness of these ectoparasites.

    The considerable ability of participants to recognise fleas, to associate flea presence with changes in animals’ behaviour, and to understand the role of these ectoparasites in pathogen transmission may be attributed to information provided by veterinarians or previous experiences with flea infestations in their companion animals. In fact, about two-thirds of the participants reported prior flea infestations, which may have prompted them to seek advice from veterinarians, the most common reported source of information on fleas and flea-borne pathogens, followed by social media and the internet. The acquisition of information about zoonotic infections from veterinarians emphasises their important role in raising the awareness of owners about the ways of transmission of the pathogens to their pets and themselves [35], although in some cases the proactivity of veterinarians in passing on knowledge has been considered negligible [36, 39]. Routine consultations provide an important opportunity for veterinarians to educate owners about the health risks fleas pose. To enhance the impact of these interactions, clear and simple educational materials, such as brochures, posters, and infographics, can be displayed in clinic waiting areas to reinforce key messages and support owner understanding. Curiously, and despite the fact that advertisements on TV about the application of ectoparasiticides to prevent arthropods and vector-borne infections was a common source of information identified in previous studies [36, 43], in the present study very few participants reported the use of this communication channel to obtain information about fleas and flea-borne pathogens. Similarly, the low demand for information on these topics from physicians (less than 10% of participants) suggests that healthcare professionals are not perceived as key sources of education on the risks of vector-borne zoonotic agents for pet-owning patients [44].

    To effectively avoid and eliminate fleas, prevent flea-borne infections, and manage flea allergy dermatitis, an integrated control strategy should target both immature and adult flea stages. This strategy may involve using products containing insect growth regulators or juvenile hormone analogues, formulations with repellent or fast-killing properties, or those with combined effects on both the animal and its environment. To prevent and eliminate infestations, a range of products are available in various formulations, including collars, spot-on treatments, sprays, powders, shampoos, chewable or hard tablets, and injectables [30, 45].

    ESCCAP recommends year-round flea prevention to cover the complete activity period of the ectoparasite, as exposure is difficult to avoid [31].

    Portugal has a temperate Mediterranean climate [46], which likely creates favourable conditions for flea populations to persist throughout the year. This climate, characterized by mild winters and warm to hot summers, combined with the common outdoor access granted to pets, increases the risk of flea infestation and underscores the need for continuous preventive measures. Most participants stated that their companion animals were treated against fleas as a preventive measure, aligning with previous studies on ectoparasite control practices among dog and cat owners [33, 34, 39, 47]. About half of the participants treated their pets for ectoparasites every 3 to 4 months, followed by every 6 to 8 months, and once per month. The preference for spot-on treatments among cat owners aligns with other studies, likely due to their ease of application [47]. Similarly, oral tablets were less commonly referred to as being used by this group, probably because cats are considered to be difficult to medicate orally [47]. As the questionnaire did not include the active ingredient of the products used, the accuracy of their application according to the manufacturer’s recommendations cannot be assessed. Given that spot-on treatments were the most commonly used route among cat-only owners and owners of both animal species, and with few exceptions are effective for only 3–4 weeks, it is likely that many pets were not treated at the correct frequency. The same conclusion can be drawn for the administration of ectoparasites in tablet form, the second most commonly used product by dog owners and owners of both animal species, since the treatment schedule is between 4 and 12 weeks. Reasons for non-compliance may relate to a lack of awareness about the importance of continuous prevention, the absence of infestation (thus reducing adherence to long-term prevention protocols), or financial constraints, with the latter reported by 15.4% of participants. Flea treatment rates for all animals in the household were significantly lower among dog and cat owners than among those who owned only dogs or only cats, although the overall frequency of flea treatment did not differ significantly between these groups. A survey of dog owners in Thailand found that the cost of flea and tick prevention, especially in households with multiple dogs, was linked to less frequent use of preventive treatments. Most owners tended to use products only when their dogs were infested [37]. In the present study, only a small percentage of participants claimed to treat their animals only when fleas were detected.

    Effective prophylactic treatment should be used in conjunction with environmental control to target all life stages. Mechanical environmental measures such as frequent vacuuming, washing pet bedding, and cleaning all areas that may harbour eggs can significantly reduce the household flea burden [6, 32, 50]. Interestingly, cleaning, vacuuming, and applying insecticides to the house and the animal’s resting places, along with brushing the animal, were the most frequently mentioned measures for controlling infestation, suggesting that many owners are aware of the importance of these practices in managing flea infestations. Cat-only owners were significantly more likely to choose the practice of cleaning areas with a possible higher risk of infestation and presented greater willingness to ask veterinarians for advice on preventing and controlling fleas. This, together with their greater knowledge of flea morphology and the fact that indoor environments and humans can also be sources of infestation, indicates a previous history of contact with fleas. In fact, 53.2% of the respondents of this group reported prior experience with fleas, which likely explains a greater motivation to apply preventative measures. Interestingly, a significantly higher proportion of participants in this group reported keeping their animals indoors from sunset to sunrise as a control measure. This may reflect confusion with other insects active during that time, such as mosquitoes and phlebotomine sand flies.

    As mentioned earlier, multivariate analysis indicated that higher education was associated with greater knowledge of fleas and flea-borne pathogens. However, this knowledge did not lead to a higher adoption of protective practices. This discrepancy could be related to the perception that general protective measures against arthropods and arthropod-borne infections are also effective against fleas, suggesting that specific flea control measures may be unnecessary.

    Conversely, higher practice scores were observed in owners under 60 years old, those living in the AML or Centro regions, and those owning only cats or only dogs. This may reflect a greater concern for preventive measures among middle-aged participants and individuals with higher knowledge of fleas and flea-borne pathogens. Additionally, owning a single species might lead to more focused and effective infestation prevention strategies.

    Although over 30% of Portuguese households owned at least one dog or cat in 2022, respondents in this study came from only 86 of the 278 municipalities in Mainland Portugal. This limited geographical representation may have hindered a detailed analysis of how sociodemographic differences influence knowledge about fleas, the diseases they can cause, and management measures for these ectoparasites. As a result, the study’s ability to accurately identify trends in pet owners’ KP may have been affected. Future research should address this limitation by ensuring broader geographical representation, thereby strengthening the reliability of the findings.

    Another limitation was the absence of including the residence of companion animal owners, as animals living in rural areas are more exposed to fleas, which may influence the awareness of the owners regarding these ectoparasites and their management.

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  • Prognostic Value of Spontaneous Potential in Long-Term Outcomes Follow

    Prognostic Value of Spontaneous Potential in Long-Term Outcomes Follow

    Introduction

    Pulmonary vein isolation (PVI) serves as the cornerstone of atrial fibrillation (AF) catheter ablation and remains one of the most widely used treatments for paroxysmal atrial fibrillation (PAF). Currently, PVI combined with linear ablation represents the primary surgical approach for non-paroxysmal atrial fibrillation (NPAF).1–4 In clinical practice, the long-term efficacy of standalone PVI for NPAF remains suboptimal. Advancements in cardiac electrophysiology suggest that AF development is associated with myocardial sleeves of the pulmonary veins, with the left atrial posterior wall also identified as a key abnormal site.5 Pulmonary vein isolation combined with left atrial posterior wall isolation (PVI+BOX) ablation involves linear ablation of the left atrial apex line and left atrial posterior wall line in addition to bilateral pulmonary vein isolation, thereby isolating both the pulmonary veins and the left atrial posterior wall from other atrial regions. However, data on BOX ablation remain limited, and existing conclusions are inconsistent.6–9

    Clinical findings indicate that spontaneous potential (SP) can be detected in the left atrial posterior wall of some patients with NPAF who have undergone PVI+BOX ablation. Previous studies indicated that most atrial premature beats (APBs) responsible for triggering AF originate from the pulmonary veins and induce AF through rapid discharges.4 During embryonic development, the left atrial posterior wall and pulmonary veins originate from the same site.10 However, whether the left atrial posterior wall SP is equivalent to spontaneous pulmonary vein potential and whether it can trigger AF remains unclear. Therefore, the relationship between left atrial posterior wall SP and long-term outcomes following PVI+BOX in patients with NPAF was investigated in this study.

    Data and Methods

    Objects

    The clinical data in this study were retrospectively collected from 140 patients with symptomatic NPAF who underwent radiofrequency ablation for the first time between 2022 and 2023. Based on the surgical approach, patients were categorized into the PVI group and the PVI+BOX group. The PVI+BOX group was further subdivided into the SP group and the no-SP group based on the presence of left atrial posterior wall SP following BOX. All patients provided informed consent before treatment, and the study received approval from the local ethics committee.

    NPAF that can be treated with catheter ablation includes persistent AF (PerAF) and long-standing persistent AF (LSPAF), as defined by the 2020 European Society of Cardiology (ESC) and European Association for Cardio-Thoracic Surgery (EACTS) guidelines for the management of AF.11 Before catheter ablation, all patients underwent transesophageal echocardiography (TEE) or left atrial computed tomography angiography (CTA) to exclude left atrial and/or left auricular thrombosis. Additionally, pulmonary vein CTA was performed to assess the anatomical structure of the pulmonary veins. All antiarrhythmic drugs were discontinued for at least five half-life periods before the procedure.

    Patients were excluded if they met any of the following criteria: (1) age younger than 18 years or older than 80 years; (2) diagnosis of valvular AF; (3) presence of hyperthyroidism; (4) history of cerebrovascular accidents or other neurological diseases within the past three months; (5) presence of other systemic diseases or tumors; (6) left atrial and/or left auricular thrombus; (7) AF of non-pulmonary vein origin; (8) prior cardiac surgery or heart disease requiring surgical intervention; (9) incomplete clinical data or failure to complete follow-up.

    The radiofrequency ablation procedure was performed with the patient in a supine position under local anesthesia with 1% lignocaine. Bilateral femoral vein punctures were made, and a 10-pole electrode was advanced into the coronary sinus via the left femoral vein, while the interatrial septum was punctured via the right femoral vein. Two 8.5F Swartz sheaths were inserted into the left atrium for the administration of 100 μg/kg heparin. A ring electrode (Biosense-Webster, USA) and a saline-irrigated electrode catheter (Biosense-Webster, USA) were introduced into the left at rium via the Swartz sheath for modeling (CARTO 3D electroanatomic mapping system), mapping, and ablation. In the PVI group, linear ablation was performed around the circumferential bilateral pulmonary vein antrum to achieve PVI. In the PVI+BOX group, linear ablation targeted the circumferential bilateral PVI, left atrial apex line, and left atrial posterior wall line to achieve posterior wall isolation. Pulmonary vein isolation was confirmed by the absence of pulmonary vein potential or the presence of SP within the pulmonary vein, with pulmonary vein pacing unable to conduct to the left atrium. Left atrial posterior wall isolation was confirmed by the absence of atrial potential (Figure 1A) or the presence of SP (Figure 1B) in the left atrial posterior wall, with left atrial posterior wall pacing unable to conduct to other atrial sites. If AF persisted following PVI or BOX ablation, synchronized electrical cardioversion (100–150 J) was administered. Ablation parameters included power (35–45 W), saline flow rate (20–30 mL/min), and impedance (140–170 Ω).

    Figure 1 (A) Absence of spontaneous potential in the left atrial posterior wall following PVI + BOX. (B) Presence of spontaneous potential in the left atrial posterior wall following PVI + BOX.

    Follow-Up

    The clinical condition of all patients was continuously monitored through 24-hour electrocardiography (ECG), blood pressure measurement, and oxygen saturation assessment after the procedure. On the first postoperative day, patients were initiated to either warfarin or a novel oral anticoagulant based on personal preference, and were informed to use it mandatorily for at least three months. Anticoagulation therapy was then continued according to the CHA2DS2-VASc score (≥ 2 for males, ≥ 3 for females). Anti-arrhythmic medications, such as amiodarone or propafenone, with or without metoprolol, were routinely administered postoperatively and discontinued after three months. Regular follow-up was conducted through clinic visits or monthly telephone consultations to evaluate AF recurrence, assessed through symptoms including palpitations, chest discomfort, shortness of breath, and fatigue. Patients underwent routine ECG examinations at local healthcare facilities, and in cases of the aforementioned symptoms, either a standard 12-lead ECG or dynamic ECG monitoring was performed. At three and twelve months postoperatively, cardiac ultrasound and 72-hour ECG monitoring were conducted at the clinic to detect AF recurrence. Follow-up data, including recurrence occurrences within three months postoperatively, were systematically documented.

    The study’s primary endpoint was the late recurrence of AF, defined as atrial tachyarrhythmia—including AF, atrial flutter, or atrial tachycardia—lasting more than 30 seconds on either a standard or dynamic ECG after all anti-arrhythmic medications were discontinued three months postoperatively.

    Statistical Analysis

    Categorical data were presented as frequency (percentage) and analyzed using the chi-square test. The Kolmogorov–Smirnov test was used to assess the normality of baseline characteristics. An independent sample t-test was conducted to compare data between the two groups, while non-normally distributed variables were expressed as median (25th–75th percentile) and analyzed using the Mann–Whitney U-test. The recurrence rate between the two groups was assessed using Kaplan-Meier survival analysis. Logistic regression was used to evaluate correlations between variables. A two-sided P < 0.05 was considered statistically significant. All statistical analyses were performed using SPSS 26.0 software.

    Results

    Basic Clinical Data

    Among the 140 patients, 78 received PVI+BOX treatment, while 62 underwent PVI only. No significant differences were observed in the clinical characteristics between these groups (Table 1). Of the 78 patients treated with PVI+BOX, 33 exhibited SP in the left atrial posterior wall, whereas 45 did not. Similarly, no significant differences were noted in the clinical characteristics between these subgroups (Table 2).

    Table 1 Baseline Characteristics of the PVI Group and PVI+BOX Group

    Table 2 Baseline Characteristics of the SP Group and No-SP Group

    Long-Term Effect

    Patients were monitored for 12 months postoperatively. In the PVI+BOX group, 24 patients (30.8%) experienced late recurrence, compared to 26 patients (41.9%) in the PVI group, with no statistically significant difference (p = 0.145; Figure 2A). In contrast, late recurrence occurred in 6 patients (18.2%) in the SP group and 18 patients (40%) in the no-SP group, showing a significant difference (p = 0.041; Figure 2B). Further analysis among the SP group, no-SP group, and PVI group indicated that the late recurrence rate was lower in the SP group than in the PVI group (p = 0.020), while no significant difference was found between the no-SP and PVI groups (p = 0.780; Figure 2B). Table 3 presents the late recurrence rates.

    Table 3 Late Recurrence Rate

    Figure 2 (A) Late recurrence-free survival curves comparing the PVI + BOX group and the PVI group. (B) Late recurrence-free survival curves comparing the SP group, no-SP group, and PVI group.

    Complications

    In the PVI+BOX group (n = 78), postoperative complications included pneumonia in 4 patients and pericardial effusion in 2 patients. In the PVI group (n = 62), 2 patients developed pneumonia, and 1 patient experienced pericardial effusion. No statistically significant difference in complication rates was observed between the groups (p > 0.05). All affected patients recovered before discharge. Table 4 presents the details on patient complications.

    Table 4 Complication Rate

    Analysis of Risk Factors for Postoperative Recurrence

    Patients who underwent PVI+BOX treatment were categorized based on late AF recurrence. Univariate analysis results are presented in Table 5. The analysis identified AF duration (p = 0.013), total cholesterol (TC) (p = 0.038), white blood cell count (WBC) (p = 0.032), and SP (p = 0.039) as risk factors for post-ablation late recurrence of NPAF (p < 0.05).

    Table 5 Single-Factor Analysis of Postoperative Recurrence

    No statistically significant differences were observed between the two groups in gender, age, body mass index (BMI), echocardiographic parameters, including left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), left atrial diameter (LAD), and ejection fraction (EF), as well as comorbidities and other factors.

    Multivariate logistic regression analysis (Table 6) identified the course of AF (odds ratio (OR): 1.026, 95% CI: 1.007–1.046, p =0.006) and SP (OR: 0.219, 95% CI: 0.057–0.835, p =0.026) as independent predictors of late AF recurrence.

    Table 6 Risk Factor Analysis for Late Recurrence

    Discussion

    Application of PVI+BOX in AF Ablation

    Since the identification of anomalous pulmonary venous activities as the primary trigger of AF, PVI has become the cornerstone of AF ablation. Over nearly two decades, it has been established as the standard procedure for AF catheter ablation, achieving a long-term success rate of 50% to 70% for paroxysmal AF. However, its effectiveness in NPAF remains limited, necessitating the incorporation of various linear ablation and substrate modification strategies. In recent years, growing recognition of the left atrial posterior wall’s role in AF occurrence and maintenance has led researchers to explore left atrial posterior wall isolation, with BOX being a commonly used approach. Nevertheless, available data on BOX ablation remain scarce, and study conclusions are inconsistent. Yamaji et al reported that left atrial posterior wall isolation could reduce postoperative recurrence in patients with NPAF.6,7 In contrast, Tamborero et al found no statistically significant difference between pulmonary vein isolation alone and its combination with left atrial posterior wall isolation in preventing arrhythmia recurrence.8,9

    While recent studies, such as Yan et al, have compared radiofrequency ablation (RFA) guided by ablation index (RFCA-AI) and second-generation cryoballoon ablation (CBA-2) in AF treatment, the role of spontaneous potential (SP) in the left atrial posterior wall following PVI+BOX ablation remains unexplored.12 Our study addresses this gap by evaluating SP as a novel predictor of long-term success after PVI+BOX, providing new insights into AF ablation strategies for NPAF patients.

    Analysis of Risk Factors for Postoperative Recurrence

    Several factors contribute to atrial substrate changes in patients with AF; however, the specific underlying mechanism remains unclear. Structural, electrical, and neural remodeling of the atrium are known to influence this process. Research has indicated a correlation between AF duration and post-ablation recurrence, with prolonged AF duration associated with a higher recurrence rate. The likely explanation is that an extended AF course increases the likelihood of atrial electrical and anatomical remodeling, making these changes irreversible and thereby significantly elevating the recurrence rate. In this study, univariate analysis of AF duration revealed that patients in the recurrence group had a significantly longer AF duration (30.5 [12–90] months) compared to the non-recurrence group (13 [7–36] months). Furthermore, multivariate analysis identified AF duration as an independent risk factor for post-ablation AF recurrence.

    Distribution and Generation Mechanism of SP

    Pulmonary veins exhibit distinct electrophysiological properties that contribute to the initiation and maintenance of AF. Pulmonary vein SP refers to spontaneous electrical activity generated by the pulmonary vein independent of the left atrium following PVI, with bidirectional PVI serving as a recognized endpoint of pulmonary vein ablation.13,14 Pulmonary vein SP commonly manifests in three forms: sporadic isolated ectopic beats, slow and regular ectopic rhythms, and rapid fibrillation potential activity.13,15 The primary mechanisms underlying pulmonary vein SP include (1) the focal mechanism, in which Jiang et al identified autorhythmic electrical activity as its principal cause.16 Studies have indicated the presence of P cells, transitional cells, and Purkinje cells within the myocardial sleeves of pulmonary veins, suggesting that pulmonary vein SP may result from electrical activity produced by autorhythmic cells.17 (2) The reentrant mechanism, characterized by pronounced spatial heterogeneity in atrial action potential duration and a shortened plateau phase, elevates the risk of reentrant arrhythmias. (3) The AF trigger mechanism, as described by Yves et al, suggests that an AF-triggered pulmonary vein predicts AF recurrence following pulmonary vein isolation.18 In such cases, pulmonary vein conduction is restored, leading to the occurrence of pulmonary vein SP, which has been frequently observed in AF-triggered pulmonary veins after circumferential PVI.19

    There are currently limited studies on left atrial posterior wall SP. The left atrial posterior wall shares an embryological origin with the pulmonary vein, and its distinct histology and anatomical structures make it a crucial substrate for sustaining AF. It serves as a trigger for AF, with its electrophysiological properties contributing to AF maintenance. Prolonged AF episodes induce both electrophysiological and structural alterations, further facilitating AF persistence.20 Embryologically, the smooth posterior wall is anatomically adjacent to the surrounding muscle trabecular tissue derived from the primitive left atrium. Due to this embryological origin, its electrophysiological characteristics more closely resemble the myocardial sleeves of pulmonary veins rather than the adjacent superior and inferior tissues.20

    Electrophysiologically, pulmonary veins and cardiomyocytes in the posterior wall exhibit distinct electrophysiological and ion channel properties, which may contribute to arrhythmogenesis.21 Anatomically, the cardiac muscle fibers of the left atrial posterior wall, particularly near the pulmonary vein junction, are oriented in varying directions. Consequently, conduction velocity and depolarization between adjacent tissues differ, and the transition between the epicardial and endocardial layers may exhibit heterogeneous anisotropy, potentially resulting in conduction delays, unidirectional blocks, and localized reentry.22 These features of the posterior wall of the left atrium may cause SP in the left atrial posterior wall to trigger reentrant mechanism or focal mechanism similar to pulmonary vein potentials. These unique characteristics of the left atrial posterior wall may contribute to AF initiation and maintenance.

    Analysis of Risk Factors for Postoperative Recurrence

    In this study, pulmonary vein isolation combined with posterior wall isolation did not show a significant difference in reducing NPAF compared to pulmonary vein isolation alone. Among patients with NPAF who underwent pulmonary vein isolation with posterior wall isolation, the recurrence rate was lower in the left atrial posterior wall SP group than in the left atrial posterior wall no-SP group. Additionally, the recurrence rate in the SP group was lower than in the simple PVI group, whereas no significant difference was observed between the no-SP group and the PVI group. This finding suggests that left atrial posterior wall SP may indicate the presence of a trigger focus outside the pulmonary vein, leading to posterior wall isolation and subsequently reducing AF recurrence. Patients without SP of the posterior left atrial wall may have other unknown lesions or triggering mechanisms, and posterior wall isolation has a relatively unsatisfactory therapeutic effect on them.

    Unlike Yan et al, which primarily focused on comparing different ablation techniques, our study introduces SP as a novel factor influencing AF recurrence after PVI+BOX ablation.12 By identifying SP as a potential predictor of improved ablation success, this study provides new mechanistic insights into the role of left atrial substrate properties in AF recurrence.

    White blood cells and neutrophils, as important indicators of the inflammatory system, their counts also reflect the degree of the inflammatory response. Previous studies have shown that patients with postoperative atrial fibrillation have significantly elevated peripheral blood white blood cells, and patients with significantly elevated white blood cells also have a longer duration of atrial fibrillation attacks. The increase of white blood cell count and neutrophil count, which are important indicators of the inflammatory system, is a risk factor for the maintenance of atrial fibrillation.

    Limitations

    In this study, SP has a certain degree of variability, the length of the recording time may affect the incidence of spontaneous potential. It is a single-center, small-sample, retrospective study, and postoperative AF recurrence was not recorded for some patients, potentially leading to discrepancies between the observed and actual long-term recurrence rates. Further multi-center studies are required to investigate the optimal degree of PVI+BOX.

    Conclusion

    SP following left atrial posterior wall isolation suggests a better long-term outcome for NPAF after PVI with BOX catheter ablation. The long-term outcome of non-paroxysmal atrial fibrillation refers to the free recurrence rate after 3 months of ablation.

    Abbreviations

    AF, Atrial Fibrillation; BMI, Body Mass Index; CAD, Coronary Artery Disease; CTA, Computerized Tomography Angiography; HCM, Hypertrophic Cardiomyopathy; HDL-C, High density lipoprotein cholesterol; LAD, Left Atrial Diameter; LDL-C, Low density lipoprotein cholesterol; LSPAF, Long-standing Persistent Atrial Fibrillation; LVEDD, Left Ventricular End-diastolic Diameter; LVEF, Left Ventricular Ejection Fraction; LVESD, Left Ventricular End-systolic Diameter; NE, Number of central granulocytes; NT-proBNP, N-terminal pro-B-type Natriuretic Peptide; PAF, Paroxysmal Atrial Fibrillation; PerAF, Persistent Atrial Fibrillation; PVI, Pulmonary Vein Isolation; Scr, Serum Creatinine; SP, Spontaneous potential; TC, Total cholesterol; TG, Triglyceride; WBC, White blood cell count.

    Data Sharing Statement

    All data generated or analyzed during this study are included in this article. Further enquiries can be directed to the corresponding author.

    Ethics Approval and Consent to Participate

    This study was conducted with approval from the Ethics Committee of Fujian Medical University Union Hospital (Approval Number: 2024KY085). This study was conducted in accordance with the declaration of Helsinki. Written informed consent was obtained from all participants.

    Funding

    This work was supported by the Fujian Provincial Health Technology Project (2021CXB003) and Fujian Provincial Natural Science Foundation of China (2023J01663).

    Disclosure

    The authors declare that they have no conflicts of interest in this work.

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