Medication Non-Adherence After Myocardial Infarction: An Exploration of Modifying Factors

Medication non-adherence is a major impediment to the management of cardiovascular disease risk factors. A better understanding of the modifying factors underlying medication non-adherence among individuals with known cardiovascular disease may inform approaches for addressing non-adherence. The purpose of this study was to identify demographic and patient characteristics, medical comorbidities, psychosocial factors, and health belief-related factors associated with medication non-adherence among patients with known cardiovascular disease. We performed secondary analysis of baseline data from a randomized trial. The study included 405 patients with a diagnosis of hypertension and history of acute myocardial infarction that was diagnosed within a three-year period prior to enrollment. Baseline demographics and patient characteristics, medical comorbidities, psychosocial factors, health belief-related factors, and patient-reported medication non-adherence were analyzed. Of 405 patients, 173 (42.7 %) reported medication non-adherence. Factors associated with non-adherence in bivariate analysis included younger age, non-white race, having less than 12 years of education, smoking, financial insecurity, identifying as nervous or tense, higher life chaos score, greater worry about having a myocardial infarction, and greater worry about having a stroke. Using multivariable modeling, we determined that age (OR 0.97 per additional year, 95 % CI, 0.95-0.99), life chaos (OR 1.06 per additional point, 95 % CI, 1.00-1.11), and worry about stroke (OR 1.12 per additional point, 95 % CI, 1.01-1.25) remained significantly associated with self-reported medication non-adherence. We found that worry about having a stroke, higher life chaos, and younger age were all significantly associated with self-reported medication non-adherence in patients with cardiovascular disease and a history of myocardial infarction. Further research exploring these factors as targets for intervention is needed, as is additional research examining modifiable causes of medication non-adherence among patients with cardiovascular disease.