Length of initial prescription at hospital discharge and long-term medication adherence for elderly patients with coronary artery disease: a population-level study.

BACKGROUND: Patient adherence to cardiac secondary prevention medications declines over time. We examined whether the length of the initial prescription at hospital discharge after coronary angiography would be associated with long-term adherence.
METHODS: We conducted a population-level cohort study to examine adherence to cardiac medications for 18 months after coronary angiography in elderly patients with coronary artery disease (CAD). We identified patients with clinical indications for angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (ACE-I/ARB), beta-blockers (BB), and/or statins. In each medication class cohort, we defined high adherence as proportion of days covered (PDC) > 80%. The length of the initial prescription was defined as 0-30 days, 31-60 days, and more than 60 days. We controlled for patient sociodemographic factors, previous adherence, and comorbidities.
RESULTS: The ACE-I/ARB cohort included 13,305 patients, the BB cohort included 5,792 patients, and the statin cohort included 16,134 patients. Using < 30 days as the reference, initial prescriptions covering at least 60 days were more likely to result in high long-term adherence for ACE-I/ARB (adjusted odds ratio [aOR], 4.1; 95% confidence interval [CI], 3.6-4.7); BB (aOR, 2.4; 95% CI, 1.9-3.1), and statins (aOR, 3.0; 95% CI, 2.6-3.4). More than 80% of patients had outpatient follow-up with a primary care provider within 30 days, and this did not vary based on length of initial prescription.
CONCLUSIONS: Giving patients longer prescriptions for cardiac secondary prevention medications at hospital discharge seems to increase the likelihood of high long-term adherence in elderly patients.