Association between orthostatic blood pressure change and masked and white coat hypertension: the Nagahama study.
BACKGROUND: Exaggerated blood pressure (BP) response to orthostatic stimuli is indicative of cardiovascular frailty and may be associated with masked and white coat hypertension, which are BP abnormalities associated with cardiovascular outcomes. We aimed to clarify this possible association in a cross-sectional analysis of a large general population. METHODS: We enrolled 7618 community residents (mean age: 57.7 years). Orthostatic BP change was calculated as the difference between systolic BP measured in a seated position and at 3 min after standing. Orthostatic hypertension and hypotension were defined as >20 mmHg increase or decrease in systolic BP, respectively. Masked and white coat hypertension were defined based on office and home morning BP measurements. RESULTS: The frequency of orthostatic hypotension and hypertension was 1.8% and 1.6%, respectively. A significant association was observed between orthostatic BP change and office-to-home BP differences, that is, the greater the increase in orthostatic BP, the higher the home BP than the office BP. The association between orthostatic hypertension and masked hypertension (crude odds ratio: 3.15; P  < 0.001) remained significant even after adjusting for potential covariates, including office seated BP. In addition, orthostatic hypotension was independently associated with white coat hypertension (crude odds ratio: 2.14; P  = 0.002). Orthostatic BP change measured at 3 min showed a clearer association with masked and white coat hypertension than that measured at 1 min. CONCLUSION: We identified a physiological association between exaggerated postural BP variability and office-to-home BP differences, which were previously considered unrelated.