When self-monitoring of home BP (HBP) is performed in daily life, exceptionally high BP readings (a so-called “outlier”) are sometimes experienced. We tested the hypothesis that outlier BP readings in HBP, one of the measures of BP variability, contributes to the remodeling of ascending Aorta, a potent risk of cardiovascular disease.Design and Method:
We conducted a cross-sectional study in 57 hypertensive or possible hypertensives as a part of the Real BP study. The subjects performed HBP monitoring using the telemonitoring system (Medical Link, Omron Healthcare Co., Kyoto, Japan), and measured their HBP consecutively three times in the morning and evening for seven days. We used maximum value of systolic BP (max SBP) as an outlier of HBP. We evaluated their ARD/body surface area (BSA), left ventricular mass (LVM)/BSA by echocardiography, and brachial-ankle pulse wave velocity (baPWV) by a volume-plethysmographic device.Results:
The subjects consisted of 30 men and 27 women, and the mean age was 66.4 ± 11.1 yrs. In multiple regression analysis adjusting for age, sex, smoking, and dyslipidemia, max SBP was correlated with ARD/BSA (r = 0.359, p < 0.05), baPWV (r = 0.337, p < 0.05), and LVM/BSA (r = 0.273, p < 0.05). In contrast, mean SBP was correlated with baPWV (r = 0.298, p < 0.05) and LVM/BSA (r = 0.290, p < 0.05), but not with ARD/BSA (r = 0.254, p = 0.09).Conclusions:
These data suggest that maximum value of home SBP, usually discarded as an outlier reading, is associated with aortic remodeling, LV mass, and arterial stiffness. Especially max SBP, but not mean SBP, was significantly correlated with regarding ARD. An outlier reading in self-monitoring of HBP could be a marker of target organ damage, and therefore a possible risk factor for future cardiovascular events.