Changing to a dry powder inhaler (DPI) was associated with more healthcare use by adult patients with asthma, based on data from approximately 260,000 individuals.
The Veterans Health Administration adopted a formulary change in 2021 that switched from the standard budesonide-formoterol metered-dose therapy to fluticasone-salmeterol dry powder therapy, but differences in patient outcomes after the change have not been well-studied, wrote Alexander Rabin, MD, of the University of Michigan, Ann Arbor, Michigan, and colleagues.
The change affected hundreds of thousands of veterans, and the researchers wanted to understand how this large-scale shift in prescribing affected clinical outcomes, Rabin said in an interview.
The formulary change was driven by a contract renegotiation and cost considerations rather than environmental concerns, but there is great interest in understanding differences in clinical outcomes between metered-dose inhalers (MDIs) and DPIs because DPIs lack the aerosol propellants that may contribute to global warming, Rabin noted. “The VA’s [Veterans Affairs] policy shift created a natural experiment to study the clinical effects of switching from MDIs to DPIs on a broad scale,” he said.
The researchers used data from the US VA healthcare system from January 2018 through December 2022 to design a matched observational cohort study and a within-person self-controlled case series (SCCS). They measured rescue medication use, emergency department visits, and hospitalizations before and after the formulary change.
The study population for the SCCS included 260,268 patients with asthma who switched from the standard metered-dose therapy to dry powder therapy; the median age was 71 years, and 91% were men.
Although the period of DPI use was associated with a 10% decrease in albuterol fills compared with periods of MDI use, it was associated with a 2% increase in prednisone fills, a 5% increase in all-cause emergency department visits, a 6% increase in respiratory-related emergency department visits, an 8% increase in all-cause hospitalizations, a 10% increase in respiratory-related hospitalizations, and a 24% increase in pneumonia-specific hospitalizations.
The cohort study included 258,557 patients who switched to a DPI and matched patients who did not. The mean age in this group was 68.9 years; 94% were men. At 180 days after the switch, patients who switched to a DPI experienced increases in all-cause hospitalizations compared with those who didn’t switch (16.14% vs 15.64%). Patients who switched also had more respiratory-related hospitalizations and pneumonia-related hospitalizations compared with the control group (3.15% vs 2.74% and 1.15% vs 1.03%, respectively). However, no differences in mortality were noted.
The researchers had heard anecdotally from colleagues and patients that the DPI version of fluticasone-salmeterol might be less well tolerated than MDI budesonide-formoterol, Rabin told Medscape Medical News. “Still, we were surprised to see evidence of worse outcomes, including increased emergency department visits and hospitalizations for COPD [chronic obstructive pulmonary disease] and asthma exacerbations,” he said.
“We had hoped the transition might be neutral or even beneficial because the fluticasone-salmeterol DPI is both less expensive and more climate-friendly than the budesonide-formoterol MDI, but the data showed there was an association with increased healthcare utilization after the switch,” he noted.
Data Support Flexible Prescribing
In light of the study findings, the researchers are working with the VA Pharmacy Benefits Management Services to review the formulary decision and consider more flexibility around prescribing budesonide-formoterol when clinically appropriate, Rabin said. “This experience also highlights a broader opportunity: To improve how large systems implement medication or device changes,” he said. “Transitions like these can create confusion or disruption for patients and clinicians alike, but better communication, training, and support could help ensure that changes are both clinically effective and patient-centered,” he said.
“We don’t yet know whether the worse outcomes were due to differences in the medications themselves (fluticasone vs budesonide), the delivery devices (DPI vs MDI), or the way the switch was implemented,” Rabin told Medscape Medical News.
The researchers are collecting qualitative data from veterans and providers to understand their experiences with the formulary change, he said. “As the healthcare community looks to reduce the environmental impact of respiratory care, it is essential that we do so in ways that protect, and ideally improve, patient outcomes. Sustainable solutions must be safe, effective, and equitable for those we serve,” he added.
Nonmedical switching of medications because of insurance coverage or other reasons not decided by clinicians is happening more frequently, said David M. Mannino III, MD, pulmonologist and professor at the University of Kentucky, Lexington, Kentucky, in an interview.
The VA population tends to be sicker, poorer, and more complicated than the general medical population; therefore, the increased use of health resources was not unexpected, said Mannino. “In general, it is a bit more difficult to use a DPI, so in many practices, sicker patients tend to be on MDIs or nebulizers,” he noted. “Forcing patients to switch might cause complications if they are not able to properly use the device they were switched to,” he said. The current study looked at the data in different ways, and the findings for a higher risk for pneumonia and emergency department visits were consistently increased, although there was no increased risk for death, he said.
“These data are compelling,” Mannino told Medscape Medical News. “I think the VA system that instituted these changes needs to take a close look at these data and consider whether other factors need to be included in future decision-making,” he said.
The current study had limitations inherent in its design, such as a lack of data that any of the medication was taken vs prescribed, Mannino noted. Other options, such as nebulizers, could be used in some patients, and newer medications now available to treat COPD might be an adequate alternative to inhalers, he added.
The study was supported by the US Department of VA Office of Health Systems Research. The researchers had no financial conflicts of interest. Mannino disclosed serving as a consultant to both GSK (makers of Advair) and AstraZeneca (makers of Symbicort), and consulting with other companies who make or are developing COPD therapies, including Chiesi Farmaceutici, Regeneron Pharmaceuticals, Roche, Sanofi, Amgen, and Lilly.