Relationship Between Screening-Detected Atrial Fibrillation and Blood Pressure Levels in Elderly Hypertensive Patients: The OMRON Heart Study

Hypertension is a well-known risk factor for atrial fibrillation (AF) and strokes, but studies assessing screening-detected AF in hypertensive populations and its relationship to the blood pressure (BP) are scarce. We prospectively recruited hypertensive patients (aged ≥60 years) from all over Japan in a decentralized clinical trial. Participants were asked to measure their electrocardiogram (ECG) and BP at home for 3 months with a BP monitor equipped with ECG. Between April 2022 and July 2023, 4,078 hypertensive patients from across the country participated in this study. The mean age was 66.3 ± 5.5 years, and the male proportion was 80.3%. After excluding those with no measurement data (n = 258), AF detection was 5.8% (n = 220/3,820), and the time to AF detection was 3 to 109 days (median 28 days). The mean BP at baseline was 133 ± 14/85 ± 9 mmHg in the morning and 125 ± 14/79 ± 9 mmHg in the evening. AF detection did not significantly differ between the baseline BP categories (log rank test, p = 0.54), with hazard ratios (95% confidence interval) of 0.83 (0.57–1.19), 0.79 (0.55–1.14), and 0.99 (0.59–1.68) for systolic BP (SBP) 135 to 144 and/or diastolic BP (DBP) 85 to 89, SBP 145 to 159 and/or DBP 90 to 99, and SBP ≥ 160 and/or DBP ≥ 100, respectively (SBP ≤ 134 and DBP ≤ 84 as a reference). The results did not change when taking into account the impact of the measurement rates and antihypertensive drugs on AF detection during the observation period. Detection of undiagnosed AF was 5.8% in elderly hypertensives, with no significant differences between the baseline BP categories and no effect of the measurement rate or antihypertensive drugs.