Does dosing antihypertensive drugs at night alter renal or cardiovascular outcome: do we have the evidence?

PURPOSE OF REVIEW: Recent evidence suggests that blood pressure during nighttime and the early morning hours is associated with increased cardiovascular risk independently of the average 24 h blood pressure. The review aims to investigate whether nighttime administration of antihypertensive drugs alters the circadian blood pressure variation and prevents hypertension-induced target organ damage and cardiovascular or renal disease. RECENT FINDINGS: Several studies showed that nighttime administration of antihypertensive drugs has a larger blood pressure lowering effect during nighttime and the early morning hours. Some studies of intermediate endpoints, such as albuminuria, ventricular hypertrophy and carotid thickness suggested beneficial effects of nighttime administration of drugs. Few long-term outcome studies showed impressive cardiovascular protection using nighttime administration of antihypertensive drugs. Owing to methodological issues, however, these studies cannot prove whether, for the same 24 h blood pressure reduction, nighttime dosing provides greater cardiovascular and renal protection than the conventional morning dosing. SUMMARY: Whether nighttime dosing is superior to the conventional morning dosing in improving cardiovascular or renal outcome remains unclear. Randomized outcome studies comparing the same treatment administered in the morning versus at nighttime are needed. Until these data become available nighttime dosing of antihypertensive drugs cannot be recommended.