Long-term adherence with cardiovascular drug regimens.

Background: An increasing number of medications are prescribed for patients with coronary artery disease, but poor adherence may limit realization of their benefits.

Objective: To characterize adherence to evidence-based cardiovascular medications prescribed at hospital discharge at 1 year.

Methods: We studied 1326 patients with coronary artery disease undergoing cardiac catheterization between 1998 and 2001. We examined adherence to angiotensin-converting enzyme (ACE) inhibitors, aspirin, beta-blockers (BBs), and statins by comparing baseline prescription at hospital discharge to self-reported medical regimen at 12 months. Patients who reported use of each cardiac medication at 1 year were considered adherent. Clinical and demographic predictors of nonadherence are described.

Results: The population had a mean age of 65.7 +/- 10.5 years, and 36% were women. At discharge, aspirin was prescribed in 95%, BBs in 86%, ACE inhibitors in 65%, and statins in 55%. The proportion of patients who discontinued medications was lowest for aspirin (18%) and BBs (22%) and highest for ACE inhibitors/angiotensin receptor blockers (28%) and statins (28%). Only 54% were adherent to all of their initial medications. Patients who discontinued medications were more likely to be older, women, unmarried, and less educated. Multivariable predictors of better adherence were higher mental health, education level, marital status, and no antidepressant use. A higher number of prescribed medications were associated with lower adherence to the recommended regimen. Insurance coverage and physical function did not correlate with adherence.

Conclusions: Patients frequently stop medications within 1 year of prescription. Adherence is influenced by marital status, mental health, education, and total number of medications prescribed. Physicians need to be aware of patient factors which influence adherence to facilitate higher use of evidence-based medications.