Maximum value of home blood pressure: a novel indicator of target organ damage in hypertension

The maximum office systolic blood pressure (SBP) has been shown to be a strong predictor of cardiovascular events, independently of the mean SBP level. However, the clinical implications of maximum home SBP have never been reported. We investigated the association between the maximum home SBP and target organ damage (TOD). We assessed the left ventricular mass index (LVMI) and carotid intima-media thickness (IMT) using ultrasonography and the urinary albumin/creatinine ratio (UACR) as measures of TOD in 356 never-treated hypertensive subjects. Home BP was taken in triplicate in the morning and evening, respectively, for 14 consecutive days with a memory-equipped device. The maximum home SBP was defined as the maximum mean triplicate BP reading in the 14-day period for each individual and was significantly correlated with LVMI (r=0.51, P<0.001), carotid IMT (r=0.40, P<0.001), and UACR (r=0.29, P<0.001). The correlation coefficients with LVMI and carotid IMT were significantly larger for the maximum home SBP than the mean home SBP. In multivariate regression analyses, the maximum home SBP was independently associated with LVMI and carotid IMT, regardless of the mean home BP level. In the prediction of left ventricular hypertrophy and carotid atherosclerosis, the goodness-of-fit of the model was significantly improved when the maximum home SBP was added to the sum of the mean office and home BPs (P=0.002 and P<0.001, respectively). These findings indicate that assessment of the maximum home SBP, in addition to the mean home SBP, might increase the predictive value of hypertensive TOD in the heart and artery.