Cardiac medication prescribing and adherence after acute myocardial infarction in Chinese and South Asian Canadian patients

Retrospective-cohort study of elderly AMI survivors (1995-2002) using administrative data from British Columbia. AMI cases and ethnicity were identified using validated ICD-9/10 coding and surname algorithms, respectively. Medication adherence was assessed using the 'proportion of days covered' (PDC) metric with a PDC ≥ 0.80 indicating optimal adherence. The independent effect of ethnicity on adherence was assessed using multivariable modeling, adjusting for socio-demographic and clinical characteristics.There were 9926 elderly AMI survivors (258 Chinese, 511 South Asian patients). More Chinese patients were prescribed BBs (79.7% vs. 73.1%, p = 0.04) and more South Asian patients were prescribed statins (73.5% vs. 65.2%, p = 0.001). Both Chinese (Odds Ratio [OR] 0.53; 95%CI, 0.39-0.73; p < 0.0001) and South Asian (OR 0.78; 95%CI, 0.61-0.99; p = 0.04) patients were less adherent to ACEI compared to Non-Asian patients. South Asian patients were more adherent to BBs (OR 1.3; 95%CI, 1.04-1.62; p = 0.02). There was no difference in prescribing of ACEI, nor adherence to statins among the ethnicities.Despite a higher likelihood of being prescribed evidence-based therapies following AMI, Chinese and South Asian patients were less likely to adhere to ACEI compared to their Non-Asian counterparts.Acute myocardial infarction (AMI) is one of the leading causes of death across multiple ethnic groups in North America. Landmark clinical trials established the efficacy of medications in reducing morbidity and mortality associated with AMI [1-3]. The morbidity and mortality benefits observed in these trials were largely among patients who were highly adherent. However, in real-world settings, typical adherence rates for prescribed medications are 50%, and are even lower in developing countries [4,5]. Medication non-adherence is associated with substantial worsening of disease, increased health care costs, and death [6-9]. From re-hospitalizations to lost workdays, the collective eco