Sex Differences in Barriers to Antihypertensive Medication Adherence: Findings from the Cohort Study of Medication Adherence Among Older Adults

Abstract

To determine whether sociodemographic, clinical, healthcare system, psychosocial, and behavioral factors are differentially associated with low antihypertensive medication adherence scores in older men and women. Cross-sectional analysis of baseline data. Cohort Study of Medication Adherence in Older Adults (N=2,194). Low antihypertensive medication adherence was defined as a score less than 6 on the 8-item Morisky Medication Adherence Scale. Information on risk factors for low adherence was collected using telephone surveys and administrative databases. The prevalence of low medication adherence scores did not differ according to sex (women, 15.0%; men 13.1%; P=.21). In sex-specific multivariable models, having problems with medication cost and practicing fewer lifestyle modifications for blood pressure control were associated with low adherence scores in men and women. Factors associated with low adherence scores in men but not women were poor sexual functioning (odds ratio (OR)=2.03, 95% confidence interval (CI)=1.31-3.16 for men and OR=1.28, 95% CI=0.90-1.82 for women), and body mass index of 25.0kg/m(2) or more (OR=3.23, 95% CI=1.59-6.59 for men; OR=1.23, 95% CI=0.82-1.85 for women). Factors associated with low adherence scores in women but not men included dissatisfaction with communication with their healthcare provider (OR=1.75, 95% CI=1.16-2.65 for women; OR=1.16, 95% CI=0.57-2.34 for men) and depressive symptoms (OR=2.29, 95% CI=1.55-3.38 for women; OR=0.93, 95% CI=0.48-1.80 for men). Factors associated with low antihypertensive medication adherence scores differed according to sex. Interventions designed to improve adherence in older adults should be customized to account for the sex of the target population.