Nationwide Study Shows Pharmacy Closure Associated with Significant Decrease in Adherence to Cardiovascular Medications

Swathi Venkatesan, M.D.
By Swathi Venkatesan, M.D. on

According to a new national study led by Dr. Dima M. Qato that was recently published in JAMA Network Open, among 3.1 million Americans 50 years and older filling cardiovascular medications at pharmacies that eventually closed, there was a significant and immediate decline in medication adherence.  This change in adherence persisted over 12 months and was prominent among older adults living in neighborhoods with fewer pharmacies.

In today’s society, nonadherence occurs in approximately 50% of patients taking prescription medications, including cardiovascular medication. Despite ongoing efforts to improve the affordability of prescription medications among older adults, nonadherence persists as an important public health problem. It is increasingly recognized that older adults may encounter system-level hurdles to adherence beyond the high cost of prescription drugs. One known barrier is pharmacy accessibility. The geographic accessibility of pharmacies varies substantially across communities in the United States, and pharmacy closures may decrease pharmacy access and thereby limit patients’ ability to fill and adhere to prescribed medications. Such closures, which disproportionately influence independent pharmacies located in low-income urban and rural neighborhoods, have increased significantly since the implementation of Medicare Part D. With the expanding role of Pharmacy Benefit Managers (PBM) in the pharmacy industry due to mergers and acquisitions, pharmacy closures are expected to further increase.

“Declines in adherence were most pronounced among older adults using independent pharmacies, purchasing from a single store to fill all their prescriptions, or living in low-access neighborhoods with fewer pharmacies and were consistent across several classes of cardiovascular medications. Our findings underscore the substantial influence of system-level factors beyond the high cost of prescription drugs on medication nonadherence, especially among patients at highest risk.”- Dima M. Qato PharmD, M.P.H., Ph.D.

In this retrospective cohort study, a nationally representative 5% random sample was used of individuals within IQVIAL Rx LifeLink data followed up between January 1, 2011, and December 31, 2016.  These anonymized, longitudinal, individual-level all-payer pharmacy claims are sampled from more than 240 million patients who fill prescription medications at retail pharmacies in the United States.  Data was collected weekly from approximately 56,000 retail pharmacies throughout the United States.  Detailed prescription information was captured for all patients across all retail and nonretail pharmacies, including dispensing pharmacy type, mail order, method of payment, co-payment amount, and pharmacy location.  The patients included in the study were divided into two groups: closure cohort and non-closure (control) cohort. For the patients in the closure cohort, adherence was measured over the 12 months prior to closure of the pharmacy, as well as the 12 months after closure. For the patients in the non-closure cohort, a date was randomly selected, and adherence 12 months before and after this date were assessed. Adherence between the two groups was compared before and after the random date or date of pharmacy closure (depending on the group). The same analysis was performed for three different drug classes: statins, beta blockers, and oral anticoagulants.

Of the 3,089,803 of individuals who filled at least one statin prescription between January 1, 2011, and December 31, 2016, 3.0% (92,287) filled at a pharmacy that later closed.  Statin adherence decreased by 5.90% (95% CI 6.12% to 5.69% decrease) after pharmacy closure. This finding was consistent in patients who were receiving beta-blockers (5.71% decrease, 95% CI 5.96% to 5.46% decrease) and oral anticoagulants (5.63% decrease, 95% CI 6.24% to 5.01% decrease). This decrease was more significant in patients who were filling their prescription in independent pharmacies (7.89% decrease, 95% CI 8.32% to 7.47% decrease) or those who lived in neighborhoods with fewer pharmacies (7.98% decrease, 95% CI 8.50% to 7.47% decrease). The authors noted that the decline was immediate and persisted for the next 12 months. This finding was similar in all three drug groups when only looking at patients who were considered fully adherent prior to the date of pharmacy closure.

Although this is the first study of its kind, it does have its limitations. Experiencing a pharmacy closure could be correlated with several unobserved factors that could also influence adherence. Secondly, data was limited to patients who filled at least 1 prescription at a retail pharmacy in the United States. The study cohorts did not include patients who may have experienced primary nonadherence. Regardless, Dr. Qato highlights the importance of the findings of this study and its potential implications. She wrote, “Our findings underscore the substantial influence of system-level factors beyond the high cost of prescription drugs on medication nonadherence, especially among patients at highest risk.” Newer efforts should be administered and aimed at eliminating barriers to prescription medication adherence, keeping the role of pharmacy closures in mind, especially for high-risk patients.

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