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

Abstract

Background: 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.

Methods: 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.

Results: 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.

Conclusion: 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.