A successful intervention to improve medication adherence in Black patients with hypertension: Mediation analysis of 28-site TEAM trial

Abstract

BackgroundWe previously reported the main effects and cost-effectiveness of a successful multifaceted Team Education and Adherence Monitoring (TEAM) intervention to improve refill adherence in Black patients with hypertension. It is important to identify the key mediators or intervention components that contributed to this intervention effect. ObjectivesThis study aimed to conduct a “mediation analysis” to determine which intervention components had the largest effect on refill adherence and assess patient satisfaction with pharmacy care. MethodsA cluster-randomized trial was conducted among 576 Black patients in 28 pharmacies (14 TEAM, 14 control). TEAM participants were invited to 6 visits with a pharmacist-technician team that monitored the patient’s blood pressure and used a 9-item Brief Medication Questionnaire, Brief Goal Check, and other novel tools to identify and reduce barriers to adherence in Black patients. Control participants received printed information only. Refill adherence was defined as >80% days covered (proportion of days covered) per refill records during months 7 to 12 (postintervention); potential mediators and patient satisfaction were assessed using a research questionnaire administered at month 6. A structural probit model examined 4 potential mediators that might explain intervention success. ResultsOf 4 potential mediators, the most important factors in explaining the improvement in refill adherence (postintervention) were greater pharmacist collaboration with patient in barrier reduction (68.5% of total indirect effect) and patient use of a pillbox (27.2% of total indirect effect). Pharmacist contact with physician and suggestion of a change in regimen did not have significant effects on adherence. TEAM participants were more likely than control participants to rate their pharmacist care as “very satisfactory” (80.2% vs. 44.2%, P < 0.001) and technician care as “very satisfactory” (81.2% vs. 47.4%, P < 0.001). ConclusionRefill adherence and satisfaction can be improved in Black patients with hypertension by implementing a collaborative TEAM model with novel tools that enable community pharmacists and technicians to help identify and reduce the core barriers to adherence. Our results can be used to individualize and improve patient care and adherence outcomes in this vulnerable population.