Medication adherence in patients with stable coronary artery disease in primary care

Abstract

Introduction: Lack of research targeting non-adherence to cardiovascular medications in Russia prevents from developing effective interventions to improve adherence. The aim was to study medication adherence in patients with stable coronary artery disease in primary care. Material and methods: The study was conducted in a primary care setting of Moscow. Demography, medical history, pharmacotherapy data were obtained retrospectively from 386 coronary patients’ medical records. Medication adherence was measured by 8-item Morisky Medication Adherence Scale (MMAS-8). A statistical analysis was performed using SPSS Statistics V16.0. Results and discussion: According to the results from MMAS-8, 188 (48.7%) coronary patients had high medication adherence, 135 (35.0%) – moderate, and 63 (16.3%) – low. By the dichotomous interpretation: 48.7% (n = 188) – were adherent, 51.3% (n = 198) – were non-adherent. These groups were similar in gender distribution, age, and medical history profile (p > 0.1 for all variables). Smokers prevailed in the non-adherent group (13.6 vs. 5.3%; p = 0.009). Both groups were equally prescribed beta-blockers, antiplatelets, and statins (p > 0.1 for all). Use of fixed dose combinations (11.7 vs. 5.6%; p = 0.048) and the number of pills taken (mean 5.64 ± 1.52 vs. 5.99 ± 1.62; p = 0.029) were associated with better adherence. Higher values of total cholesterol (mean 5.2 ± 1.4 vs. 4.7 ± 1.2 mmol/L; p < 0.001) and low-density lipoprotein cholesterol (mean 2.9 ± 1.2 vs. 2.4 ± 0.9 mmol/L; p < 0.001) were revealed in non-adherents. Subjects with suboptimal adherence visited general practitioners more frequently (median 5 vs. 3 visits; p = 0,003). Conclusion: Medication non-adherence in coronary outpatients exceeded 50%. High adherence was associated with more frequent use of fixed dose combinations and fewer pills taken by patient. Smoking and poorer control of blood lipids prevailed in non-adherents, who also caused higher load on general practitioners.