Orthostatic hypertension detected by self-measured home blood pressure monitoring: A new cardiovascular risk factor for elderly hypertensives

Orthostatic blood pressure (BP) dysregulation is a risk factor for both falls and cardiovascular events. Self-measured BP, carried out at home, is both highly reproducible and useful for evaluating antihypertensive treatment. However, there have been a few reports on the clinical implications of orthostatic BP changes in home BP monitoring (HBPM). In the baseline examination for the Japan Morning Surge-1 Study, a multicenter randomized control trial, we evaluated 605 hypertensive outpatients who had a morning systolic BP above 135 mmHg. The plasma brain natriuretic peptide (BNP) level and urinary albumin excretion were measured. When the patients were divided into 10 groups, according to orthostatic BP change evaluated by HBPM, after adjusting for age, gender, body mass index and sitting home BP level, those in the top decile (n=60, orthostatic BP increase >7.8 mmHg) had a higher urinary albumin/creatinine ratio (UAR) than the lowest decile group (geometric mean [SEM range]: 209.1 [134.7-318.7] vs. 34.1 [20.1-56.2] mg/g creatinine [Cr], p=0.003) and the pooled second to ninth decile groups (n=485, 209.1 [134.7-318.7] vs. 39.7 [33.2-47.3] mg/g Cr, p<0.02). Additionally, patients in the top decile had a higher BNP level than the second to ninth decile groups (75.7 [55.0-103.1] vs. 23.6 [20.8-26.6] pg/ mL, p=0.003). Evaluation of orthostatic hypertension at home might be a high-risk factor for cardiovascular events in hypertensive subjects with increased levels of BNP and a higher UAR, independent of the home sitting BP level.