CHICAGO — Bedtime dosing of valsartan is more efficient than morning dosing in controlling blood pressure and improving renal function in hypertensive patients with or without diabetes, Ramon Hermida, Ph.D., said at the annual meeting of the American Society of Hypertension.
Dr. Hermida suggests this time-dependent effect is not unique to valsartan, but may be class related for angiotensin II receptor blockers.
Dr. Hermida randomized 204 untreated hypertensive patients to receive valsartan 160 mg/day upon awakening or at bedtime. Blood pressure was measured at 20-minute intervals from 7:00 a.m. to 11:00 p.m., and at 30-minute intervals at night for 48 hours before and after 12 weeks. Urine was collected in the first 24 hours of BP monitoring. Mean age was 52 years, and 97 had type 2 diabetes mellitus.
Bedtime dosing was significantly more efficient than morning dosing in reducing nocturnal BP in patients with or without diabetes, said Dr. Hermida, of the University of Vigo (Spain). The diurnal/nocturnal BP ratio was unchanged after taking valsartan on awakening, but significantly increased by 5.3% if taken before bedtime. Urinary albumin excretion was significantly reduced by 23% from baseline in patients without diabetes and by 31% in those with diabetes only after bedtime administration.
This reduction was independent of the significant decrease in 24-hour or diurnal mean BP post treatment. It was highly correlated with the decrease in nocturnal BP, and mainly correlated with the increase in diurnal/nocturnal BP ratio, said Dr. Hermida, who disclosed no conflicts of interest. When analyzed separately, the decrease in urinary albumin excretion associated with the increase in diurnal/nocturnal BP ratio was statistically significant for patients both with and without diabetes.