Wrist-Measured Nighttime Home BP and Left Ventricular Hypertrophy: The WISDOM-HMOD Study

BACKGROUND: Nighttime blood pressure (BP) assessed by ambulatory BP monitoring is linked to left ventricular hypertrophy and its sequelae, including heart failure. However, the association between nighttime BP measured by a wrist-type oscillometric home BP monitor-designed to be less intrusive than brachial devices-and left ventricular hypertrophy remains unclear. METHODS: The WISDOM-HMOD study (Wrist ICT-based Sleep and Circadian Blood Pressure Monitoring Program-Hypertension-Mediated Organ Damage), a substudy of the WISDOM-Night study, included 1218 patients with hypertension or heart failure (mean age, 67.2±12.0 years; 53.9% men) who were recruited between 2021 and 2024. Nighttime BPs (2:00, 3:00, and 4:00 am and 4 hours after bedtime) and morning/evening BPs over 7 days were measured using a wrist-type home BP monitor (HEM9601T; Omron). RESULTS: in women. An increase in nighttime systolic BP was significantly associated with a higher left ventricular mass index, independent of office BP, morning home BP, and evening home BP. Furthermore, elevated nighttime systolic BP was a risk factor for left ventricular hypertrophy in both sexes (odds ratio per 10-mm Hg increase, 1.36 [95% CI, 1.15-1.60] overall; 1.54 [95% CI, 1.19-2.00] in men; and 1.27 [95% CI, 1.01-1.58] in women), independently of covariates including office and morning home BP. CONCLUSIONS: This study shows that nighttime home BP measured using a less sleep-disturbing wrist-type device is an independent risk factor for left ventricular hypertrophy and its potential sequelae, including new-onset or recurrent heart failure, with high-risk nighttime BP thresholds differing by sex.