Bedtime administration of long-acting antihypertensive drugs restores normal nocturnal blood pressure fall in nondippers with essential hypertension

Nondipper hypertensive patients have more pronounced target organ injury. We examined whether shifting the time of dosing long-acting antihypertensive drugs from morning to bedtime reduces nocturnal blood pressure (BP) and restores normal nocturnal dipping in nondippers with essential hypertension. We studied 71 Japanese hypertensive patients who received long-acting antihypertensive drugs once daily in the morning using 24-h ambulatory BP monitoring. After determination of circadian BP pattern, medication time was changed to bedtime only in nondippers. Among 71 patients, 36 were classified as dippers and 35 as nondippers. After shifting administration time from morning to bedtime in 34 nondippers, the office and 24-h ambulatory BP did not change, but the diurnal BP slightly increased and nocturnal BP markedly decreased. The percentages of nocturnal decline in systolic and diastolic BP increased from 2.6% to 15.5% (P < 0.0001) and 5.6% to 16.9% (P < 0.0001). Morning BP at 7 a.m.-11 a.m. did not increase by bedtime administration. The frequency of dippers increased from 0/34 (0%) to 24/34 (71%). Adding to 50% of dippers on morning administration, 86% of the hypertensive patients became dippers by deciding the medication time according to dipper status. Nondippers on morning dosing can be changed to dippers by shifting administration time to bedtime, reducing nocturnal BP but not changing office BP, 24-h ambulatory BP or morning BP. In treating essential hypertensive patients, it is desirable to measure 24-h ambulatory BP as well as office BP and to decide the administration time of long-acting antihypertensive drugs to normalize nocturnal BP fall.