Relationship between home blood pressure and vascular function in patients receiving antihypertensive drug treatment.

Hypertension is associated with vascular failure, such as increased arterial stiffness, endothelial dysfunction, and vascular smooth muscle dysfunction. The purpose of this study was to investigate the relationship between out-of-office blood pressure and vascular function in patients receiving antihypertensive drugs. We assessed out-of-office blood pressure, including daytime and night-time blood pressure, by home blood pressure monitoring and performed vascular function tests, including brachial-ankle pulse wave velocity (baPWV), flow-mediated vasodilation (FMD), and nitroglycerine-induced vasodilation (NID), in 169 patients receiving antihypertensive drugs, of whom 86 (50.9%) had normotension, 23 (13.6%) had isolated nocturnal hypertension (night-time systolic blood pressure ≥120 mm Hg), 26 (15.4%) had isolated daytime hypertension (daytime systolic blood pressure ≥135 mm Hg), and 34 (20.1%) had sustained hypertension (daytime and nocturnal hypertension). baPWV was significantly higher in patients with sustained hypertension than in those without sustained hypertension (1585 ± 257 cm/s in normotension; 1687 ± 267 cm/s in isolated nocturnal hypertension; 1688 ± 313 cm/s in isolated daytime hypertension; and 1923 ± 399 cm/s in sustained hypertension; P < 0.001). baPWV above the cutoff value of 1858 cm/s, derived from receiver operating characteristic curve analysis to diagnose patients with sustained hypertension, was significantly associated with sustained hypertension after adjustment of other confounding factors (odds ratio, 5.01; 95% confidence interval, 1.94-13.41; P < 0.001). In contrast, there was no significant association of home blood pressure status with FMD or NID in these patients. In patients receiving antihypertensive drugs, baPWV was significantly associated with sustained hypertension, whereas FMD and NID were impaired regardless of the home blood pressure status.