Long-Term Effect of Home Blood Pressure Self-Monitoring Plus Medication Self-Titration for Patients with Hypertension: A Secondary Analysis of the ADAMPA Randomized Clinical Trial

Abstract

Importance: Patient empowerment through pharmacologic self-management is a common strategy for some chronic diseases such as diabetes, but it is rarely used for controlling blood pressure (BP). Several trials have shown its potential for reducing BP in the short term, but evidence in the longer term is scarce. Objective: To evaluate the longer-term effectiveness of BP self-monitoring plus self-titration of antihypertensive medication vs usual care for patients with poorly controlled hypertension, with passive follow-up and primary-care nursing involvement. Design, Setting, and Participants: The ADAMPA (Impact of Self-Monitoring of Blood Pressure and Self-Titration of Medication in the Control of Hypertension) study was a randomized, unblinded clinical trial with 2 parallel arms conducted in Valencia, Spain. Included participants were patients 40 years or older, with systolic BP (SBP) over 145 mm Hg and/or diastolic BP (DBP) over 90 mm Hg, recruited from July 21, 2017, to June 30, 2018 (study completion, August 25, 2020). Statistical analysis was conducted on an intention-to-treat basis from August 2022 to February 2024. Interventions: Participants were randomized 1:1 to usual care vs an individualized, prearranged plan based on BP self-monitoring plus medication self-titration. Main Outcomes and Measures: The main outome was the adjusted mean difference (AMD) in SBP between groups at 24 months of follow-up. Secondary outcomes were the AMD in DBP between groups at 24 months of follow-up, proportion of patients reaching the BP target (SBP <140 mm Hg and DBP <90 mm Hg), change in behaviors, quality of life, health service use, and adverse events. Results: Among 312 patients included in main trial, data on BP measurements at 24 months were available for 219 patients (111 in the intervention group and 108 in the control group). The mean (SD) age was 64.3 (10.1) years, and 120 patients (54.8%) were female; the mean (SD) SBP was 155.6 (13.1) mm Hg, and the mean (SD) diastolic BP was 90.8 (7.7) mm Hg. The median follow-up was 23.8 months (IQR, 19.8-24.5 months). The AMD in SBP at the end of follow-up was -3.4 mm Hg (95% CI, -4.7 to -2.1 mm Hg; P