TOPLINE:
Hydroxychloroquine exposure in patients with lupus nephritis was associated with a substantially lower risk for estimated glomerular filtration rate (eGFR) decline of ≥ 30%, particularly among those with chronic kidney disease (CKD) stage ≥ 3.
METHODOLOGY:
- Researchers conducted a retrospective study involving 209 patients with biopsy-proven incident lupus nephritis (mean age at diagnosis, 38 years; 75% women) between 1994 and 2019 identified at a single center in Wisconsin to examine the effect of hydroxychloroquine on kidney function.
- Hydroxychloroquine exposure status (median dose, > 5 vs ≤ 5 mg/kg/d) was determined at each visit using electronic health records, with positive exposure ascertained by an active prescription for at least 3 months at each follow-up.
- The primary outcome was eGFR decline of ≥ 30% at a minimum of two follow-up visits compared with baseline eGFR, or the requirement of sustained renal replacement therapy, with a mean follow-up duration of 5.4 years.
- The secondary outcome included an eGFR decline of ≥ 40%, and the annual eGFR slope to assess kidney function decline over time.
TAKEAWAY:
- Time-varying exposure to hydroxychloroquine was associated with a 59% lower risk for an eGFR decline of ≥ 30% (adjusted hazard ratio [aHR], 0.41; P = .007).
- Similarly, hydroxychloroquine exposure was associated with a 66% lower risk for an eGFR decline of ≥ 40% (aHR, 0.34; P = .004).
- In patients with CKD stage ≥ 3 at lupus nephritis diagnosis, hydroxychloroquine exposure was associated with a 77% lower risk for an eGFR decline of ≥ 30% (aHR, 0.23; P = .03).
- Exposure to hydroxychloroquine led to significant annual reductions in eGFR slope declines of 5.12 mL/min/1.73 m2 within 5 years of a lupus nephritis diagnosis and 3.17 mL/min/1.73 m2 within 10 years.
IN PRACTICE:
“These findings emphasize the importance of starting early and continuing HCQ [hydroxychloroquine] therapy to preserve kidney health alongside overall disease control even if SLE [systemic lupus erythematosus] is limited to the kidneys [lupus nephritis],” the authors of the study wrote.
SOURCE:
This study was led by Shivani Garg, MD, PhD, University of Wisconsin School of Medicine & Public Health, Madison, Wisconsin. It was published online on July 20, 2025, in Arthritis Care & Research.
LIMITATIONS:
The single academic institution setting potentially affected population representation. Data on hydroxychloroquine blood levels were unavailable to assess adherence and absorption variability. Decline of eGFR may have been missed in patients lost to follow-up or those who died at outside institutions.
DISCLOSURES:
This study received support from the University of Wisconsin-Madison, Institute for Clinical and Translational Research and the Clinical and Translational Science Award program from the National Institutes of Health (NIH) National Center for Advancing Translational Sciences. One author reported receiving funding through the NIH and honoraria for presentation at a conference.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.