Abstract 13622: Association Between Self-Reported Medication Adherence and Therapeutic Inertia in Hypertension: A Secondary Analysis of the Systolic Blood Pressure Intervention Trial (SPRINT)

Abstract

Introduction: Therapeutic inertia (TI), the failure to intensify antihypertensive medication when blood pressure (BP) is above goal, remains highly prevalent in hypertension management. The degree to which self-reported antihypertensive adherence is associated with TI when targeting intensive BP goals remains unclear. Methods: Cross-sectional analysis of the 12-month visit of participants randomized to the intensive systolic BP (SBP) arm of the SBP Intervention Trial (SPRINT), which randomized adults at high cardiovascular disease risk to an intensive (<120 mm Hg) vs. standard (<140 mm Hg) SBP treatment group. TI was defined as no change in the antihypertensive medication regimen intensity score, which incorporates the medication number and dose, when the SBP >120 mm Hg. Self-reported medication adherence was assessed using the 8-item Morisky Medication Adherence Scale (MMAS-8) and categorized as low (<6), medium (6 to <8), and high (8). Poisson regression models with robust error variance estimated prevalence ratios (PRs) and 95% confidence intervals (CIs) for TI associated with MMAS-8 category. Results: Among 1,009 intensive arm participants with SBP >120 mm Hg at the 12-month visit (mean age 69.6 years, 35.2% female, 28.8% non-Hispanic Black), TI occurred in 50.8% of participants. Participants with low self-reported adherence (vs. high) were younger and more likely to be non-Hispanic Black or current smokers. The prevalence of TI among low, medium, and high adherence was 45.0%, 53.5%, and 50.4%, respectively. After adjustment, neither low nor medium adherence (vs. high) were associated with TI (PR 1.11; 95% CI 0.87,1.42, PR 1.08; 95% CI 0.84,1.38, respectively). Conclusion: Although clinician uncertainty about medication adherence is often cited as a reason for why antihypertensive intensification is withheld when the BP is above goal, we observed no evidence of an association between self-reported adherence to antihypertensive medication and TI.