Adherence to secondary stroke prevention medications in Singapore: a single center study

Recurrent strokes are associated with greater disability and mortality than first-time strokes. However, adherence to secondary stroke prevention medications has been reported to be suboptimal. We assessed medication adherence to antihypertensives, antiplatelets, and statins after acute ischemic stroke and identified factors associated with non-adherence behavior to each drug class.

This single center study is an extension of a larger prospective cohort study of ischemic stroke patients assessed at an outpatient post stroke clinic. Medication adherence behavior and medication knowledge was determined by direct questioning, and perceptions towards medications via the Beliefs about Medicines Questionnaire. Factors associated with non-adherence in each drug class were determined using logistic regression.

Rates of adherence differed between antihypertensives (77.9%), antiplatelets (80.3%), and statins (64.7%) (p < 0.001) amongst the 193 patients surveyed. Non-adherence to antihypertensives was associated with living alone, taking < 5 medications, and stronger beliefs that medications are harmful. For antiplatelets, non-diabetic patients and patients with stronger beliefs that medications are harmful were more likely to be non-adherent. Patients non-adherent to statins were more likely to have a longer time since ischemic event and have a transient ischemic attack as the index event.

Overall, medication adherence behavior to secondary stroke prevention medications was poor, with statins the least adhered to. Factors associated with non-adherence to each drug class could guide the development of tailored interventions to improve adherence to secondary stroke prevention medications.