Medication adherence interventions among hypertensive black adults: a systematic review and meta-analysis

BACKGROUND:Black adults have higher rates of hypertension and lower rates of blood pressure (BP) control than white adults. Improving BP control requires attention to use of antihypertensive medications, but antihypertensive regimen adherence remains low, preventing improved BP control. METHODS AND RESULTS:We conducted a comprehensive search and systematic review of intervention studies testing interventions to improve adherence to BP medications among black adults with hypertension. Medication adherence effect sizes were calculated from the reported data. Summary ES were calculated using random-effects model meta-analysis methods to account for both differences in between-study effects and variation in study populations and interventions. We conducted moderator analyses to explore effect sizes differences from reported study design, sample and intervention characteristics. Funnel plots were used to assess publication bias. Comprehensive searches located 39 970 individual citations, which ultimately yielded 37 eligible studies reporting 45 interventions. Overall, interventions were found to significantly improve medication adherence (d = 0.32; 95% confidence interval0.19–0.45). Intervention effectiveness was better for medication packaging interventions, but less effective for medication counselling, social support and healthcare provider-focused interventions. Intervention effectiveness was also related to the presence of comorbidities such as diabetes and hyperlipidemia. CONCLUSION:Interventions to improve medication adherence among black adults with hypertension have a significant but modest benefit. Medication adherence should be addressed in regular follow-up visits with patients. Interventions should include components that actually change patients’ medication-taking practices, rather than focusing on counselling or social support approaches to improve adherence.