Change in Trajectories of Adherence to Lipid‐Lowering Drugs Following Non‐Fatal Acute Coronary Syndrome or Stroke

BACKGROUND: Poor adherence to cardioprotective drugs remains a concern among patients for secondary prevention. A better understanding of adherence fluctuations before and after critical health events may inform approaches for addressing or preventing poor adherence. Therefore, we assessed trajectories of adherence to lipid‐lowering drugs before and after acute coronary syndrome (ACS) or stroke and identified post‐ACS/stroke trajectories’ predictors. METHODS AND RESULTS: We conducted a cohort study of patients hospitalized for ACS or stroke in Alberta, Canada, using administrative health data between 2009 and 2015. Patients using lipid‐lowering drugs in the 2 years pre‐hospitalization and had post‐discharge follow‐up ≥365 days were included. We used group‐based trajectory modeling to assess adherence trajectories and multinomial logistic regression to assess trajectories’ predictors. In total, 10 623 patients were included. The average age was 69 years, and 65% were men. Five trajectories were identified in both periods: nearly perfect, gradual increase, gradual decline, rapid decline, and poor adherence throughout. Of patients who were poor adherers, rapidly or gradually declining pre‐hospitalization, 2395/3588 (66.8%) switched to gradual increase or perfect adherence post discharge. Conversely, of patients gradually increasing or nearly perfect before, only 4822/7035 (68.5%) were nearly perfect adherers after. Main predictors of poor post‐ACS/stroke trajectories included older age, female sex, lack of immediate post discharge follow‐up, and prior trajectories. CONCLUSIONS: This study suggests that adherence post‐ACS/stroke is highly variable and emphasizes the importance for clinicians to recognize that post‐discharge adherence will likely change negatively for prior good adherers. Adherence‐enhancing interventions should occur both early and late following discharge.