Association of nocturnal hypertension, non-dipping, and exaggerated morning surge with home blood pressure monitoring: The HI-JAMP Study

BACKGROUND Elevated nighttime blood pressure (BP), nocturnal non-dipping, and exaggerated morning BP surge (MBPS) are established risk factors for cardiovascular events. These diurnal BP variability patterns can be assessed by ambulatory BP monitoring (ABPM) but not by conventional home BP monitors. We aimed to examine whether home BP data are associated with these BP variability patterns. METHODS Treated hypertensive participants in the HI-JAMP study underwent 24-hour ABPM followed by home BP monitoring (HBPM). Home BP was measured twice each morning and evening for 5 days using a multisensor device that also recorded room temperature. A total of 2,248 participants with complete ABPM and HBPM data were analyzed. RESULTS Among 2,248 participants, ABPM-defined nocturnal hypertension was present in 679 (30.2%), exaggerated MBPS in 171 (7.7%), and nocturnal non-dipping in 969 (43.1%). Of these, 39 participants (1.8%) had both nocturnal hypertension and exaggerated MBPS. Nocturnal hypertension, exaggerated MBPS, and non-dipping were each associated with elevated morning home systolic BP (SBP) of ≥ 135 mmHg measured by HBPM (odds ratios: 3.76, 2.00, and 1.33, respectively). Nocturnal hypertension (odds ratio: 1.84) and non-dipping (odds ratio: 1.69) were associated with higher room temperature, whereas exaggerated MBPS (odds ratio: 1.86) was associated with lower room temperature, independent of elevated morning home SBP. CONCLUSIONS Individuals with high morning home BP were more likely to show abnormal diurnal BP variability. Incorporating room temperature into home BP assessments may provide additional context when interpreting home BP measurements. Clinical Trial Registration University Hospital Medical Information Network Clinical Trials Registry, UMIN000029151 (HI-JAMP study)