Analysis of Therapeutic Inertia and Race and Ethnicity in the Systolic Blood Pressure Intervention Trial: A Secondary Analysis of a Randomized Clinical Trial

Abstract

Therapeutic inertia may contribute to racial and ethnic differences in blood pressure (BP) control. To determine the association between race and ethnicity and therapeutic inertia in the Systolic Blood Pressure Intervention Trial (SPRINT). This cross-sectional study was a secondary analysis of data from SPRINT, a randomized clinical trial comparing intensive (<120 mm Hg) vs standard (<140 mm Hg) systolic BP treatment goals. Participants were enrolled between November 8, 2010, and March 15, 2013, with a median follow-up 3.26 years. Participants included adults aged 50 years or older at high risk for cardiovascular disease but without diabetes, previous stroke, or heart failure. The present analysis was restricted to participant visits with measured BP above the target goal. Analyses for the present study were performed in from October 2020 through March 2021. Self-reported race and ethnicity, mutually exclusively categorized into groups of Hispanic, non-Hispanic Black, or non-Hispanic White participants. Therapeutic inertia, defined as no antihypertensive medication intensification at each study visit where the BP was above target goal. The association between self-reported race and ethnicity and therapeutic inertia was estimated using generalized estimating equations and stratified by treatment group. Antihypertensive medication use was assessed with pill bottle inventories at each visit. Blood pressure was measured using an automated device. A total of 8556 participants, including 4141 in the standard group (22 844 participant-visits; median age, 67.0 years [IQR, 61.0-76.0 years]; 1467 women [35.4%]) and 4415 in the intensive group (35 453 participant-visits; median age, 67.0 years [IQR, 61.0-76.0 years]; 1584 women [35.9%]) with at least 1 eligible study visit were included in the present analysis. Among non-Hispanic White, non-Hispanic Black, and Hispanic participants, the overall prevalence of therapeutic inertia in the standard vs intensive groups was 59.8% (95% CI, 58.9%-60.7%) vs 56.0% (95% CI, 55.2%-56.7%), 56.8% (95% CI, 54.4%-59.2%) vs 54.5% (95% CI, 52.4%-56.6%), and 59.7% (95% CI, 56.5%-63.0%) vs 51.0% (95% CI, 47.4%-54.5%), respectively. The adjusted odds ratios in the standard and intensive groups for therapeutic inertia associated with non-Hispanic Black vs non-Hispanic White participants were 0.85 (95% CI, 0.79-0.92) and 0.94 (95% CI, 0.88-1.01), respectively. The adjusted odds ratios for therapeutic inertia comparing Hispanic vs non-Hispanic White participants were 1.00 (95% CI, 0.90-1.13) and 0.89 (95% CI, 0.79-1.00) in the standard and intensive groups, respectively. Among SPRINT participants above BP target goal, this cross-sectional study found that therapeutic inertia prevalence was similar or lower for non-Hispanic Black and Hispanic participants compared with non-Hispanic White participants. These findings suggest that a standardized approach to BP management, as used in SPRINT, may help ensure equitable care and could reduce the contribution of therapeutic inertia to disparities in hypertension. ClinicalTrials.gov identifier: NCT01206062.