The effect of evening vs. morning medication on morning blood pressure surge

Hypertension represents a significant risk factor for cardiovascular and cerebrovascular events, with the incidence of acute events peaking during the vulnerable morning hours. The morning blood pressure surge (MBPS), defined as the rise in systolic blood pressure from the nocturnal trough to the early-morning period, has been associated with increased cerebrovascular risk particularly in individuals with excessive surges, as reported in elderly hypertensive cohorts. Comprehensive searches across six medical databases resulted in the inclusion of 8 clinical trials focused on morning blood pressure surges (MBPS) and 12 trials assessing ambulatory blood pressure metrics, encompassing a total of 1239 and 1417 hypertensive patients, respectively. The findings revealed that the MBPS was significantly more reduced in patients taking medication before bedtime, averaging a decrease of 7 mmHg compared to those who took medications in the morning. Specifically, the administration of calcium channel blockers and renin-angiotensin-aldosterone inhibitors at night was associated with additional reductions in MBPS of 4 mmHg and 11 mmHg, respectively, further emphasized by a combined administration of these agents along with diuretics, which displayed an even greater reduction of 26 mmHg. Moreover, the diurnal systolic and nighttime diastolic blood pressures were found to be lower by 6 mmHg and 13 mmHg, respectively, in the nighttime medication cohort compared to their morning counterparts. This study substantiates the concept that administering antihypertensive treatment at night is more effective in controlling the MBPS, supporting bedtime dosing as an effective strategy to attenuate MBPS and improve nocturnal blood pressure control in selected hypertensive populations. Whether these improvements translate into reduced cardiovascular events requires confirmation in adequately designed outcome-based trials.