Disparities in antihypertensive medication adherence in adolescents

Background: Hypertension affects up to 5 % of all children, but little is known about the role of medication adherence on blood pressure (BP) control. In this study we examined the association between adolescents' antihypertensive medication adherence and BP control, investigating for racial disparities. Methods: A total of 21 adolescents with essential hypertension [mean age 14.7 ± 2.0 years, 57 % male, 52 % African American] were recruited from a pediatric nephrology clinic. Objective medication adherence measures were obtained with Medication Event Monitoring System (MEMS) caps and pharmacy refill records to determine medication possession ratios (MPRs). Results: The African Americans adolescents had lower medication adherence than non-African Americans adolescents based on the MPR over the past 12 months (mean 0.54 ± 0.21 vs. 0.85 ± 0.16, respectively; p < 0.001) and a trend for less adherence measured by MEMS caps over the last 28 days (mean 0.75 ±0.26 vs. 0.91 ± 0.04, respectively; p < 0.07). Seven of the eight participants with low adherence (MPR <0.65) had uncontrolled BP (systolic and/or diastolic BPs ≥95th percentile), and no participants with high adherence according to the MPR had uncontrolled BP (p < 0.001). There was no difference in BP control by race. Conclusions: Antihypertensive medication adherence measured by pharmacy refills was associated with BP control. AAs were more likely to have lower medication adherence. Targeting medication adherence through the use of electronic medical records may be a potential mechanism to reduce health disparities.