MEAN ANNUAL TEMPERATURE IN VARIOUS REGION IS ASSOCIATED WITH THE PREVALENCE OF MASKED MORNING HYPERTENSION: THE J-HOP STUDY

Abstract

Abstract Objective: Although previous studies have been reported home BP (HBP) is higher in cold region than that in warm region, regional variation in prevalence of masked hypertension remains unclear. We hypothesized that the prevalence of masked hypertension would be higher in cold region than that in warm region. Thus, we assessed the regional variation in the prevalence of masked hypertension using the dataset of the Japan Morning Home-Surge BP (J-HOP) study. Design and method: This is a cross-sectional, post-hoc analysis using the dataset of the J-HOP study, which recruited patients with a history of or risk factors of cardiovascular disease. Participants underwent consecutive 14-day HBP measurements (morning and evening). We divided participants into three regions, which were divided by mean annual temperature (< 13 degree [Celsius], 13–15 degree, 15 degree < ) in each participated facility. Masked morning or evening hypertension was defined as controlled office BP (systolic BP [SBP] < 140 mmHg and diastolic BP [DBP] < 90 mmHg) and uncontrolled morning or evening HBP (SBP > = 135 or DBP > = 85 mmHg). These criteria of BP levels were based on the Japanese guidelin on the management hypertension 2014 (JSH2014). Results: In the present study, 4268 participants (mean age, 64.9 ± 10.9 years; 46.9% male; 91.4% hypertensives) were divided 453, 1955, and 1860 partcipants into cold, moderate, and warm region, respectively. Office SBP was higher in cold region than others and morning home SBP was also higher in cold region than others. Whereas, evening home SBP had no significant differences between three regions. Moreover, in participants with normal (well-controlled) office BP, the prevalence of masked morning hypertension was higher in cold and moderate region than in warm region. However, the prevalence of masked evening hypertension had no significant differences between three regions. These relationships were also demonstrated after adjusted for traditional host factors in multivariate logistic regression analysis (All results are shown in Table). Conclusions: The present study demonstrated that the prevalence of masked morning hypertension was higher in colder regions than in warmer regions.