Effect of bedtime administration of blood-pressure lowering agents on ambulatory blood pressure monitoring results: A meta-analysis.

BACKGROUND Bedtime administration of antihypertensive drugs currently receives more at-tention, but no clear consensus has been reached on the blood pressure (BP)-lowering effect of this strategy. METHODS We systematically searched literature for clinical trials of ingestion time of anti-hypertensive drugs evaluated by ambulatory blood pressure monitoring (ABPM) to perform a meta-analysis which aimed at determining the difference in diurnal, nocturnal, and 24-h mean of systolic BP (SBP) and diastolic BP (DBP), absolute BP reduction from baseline between bedtime administration group (experimental group) and morning (awaking) administration group (control group). RESULTS The synthesis analysis showed that the level of BP in bedtime administration group was lower than the morning administration group, which reduced diurnal SBP/DBP by 1.67/1.13 mm Hg (p = 0.36/0.48), 24-h SBP/DBP by 2.78/0.36 mm Hg (p = 0.09/0.62), nocturnal SBP/DBP by 6.32/3.17 mm Hg (p = 0.03/0.007). Furthermore, there was lack of statistically significant differences in the diurnal mean of SBP/DBP reduction from baseline between the two groups (p = 0.94/0.85), but bedtime administration resulted in significant reduction from baseline in the nocturnal mean of SBP/DBP, by -4.72/-3.57 mm Hg (p = 0.01/0.05). Funnel plot demonstrated that there was no evidence of publication bias. CONCLUSIONS Administration of ≥ 1 antihypertensive drugs at bedtime or evening results in a greater reduction of nocturnal hypertension than dosing in the morning without loss of efficacy of diurnal and 24 h mean BP reduction.