Is nocturnal blood pressure reduction the secret to reducing the rate of progression of hypertensive chronic kidney disease?

Hypertension is a significant risk factor for cardiovascular and renal disease. Lowering blood pressure (BP) has been shown to reduce the incidence of cardiovascular disease, but randomized trials have not demonstrated a benefit of lowering BP for the progression of renal disease except in secondary analyses in patients with significant proteinuria. Recently, there has been increasing interest in measuring BP outside of the clinic, using both home and ambulatory blood pressure monitoring (ABPM). ABPM has the advantage of measuring BP throughout both the day and night. Elevated nighttime BP and a lack of decline in BP from day to night (nondipping) are more potent risk factors for cardiovascular and renal outcomes than elevated daytime or clinic BP. Studies have shown that it is possible to lower nighttime BP and restore normal dipping with the administration of antihypertensive medications in the evening, known as chronotherapy. Evening administration of antihypertensives not only lowers nighttime BP but also is associated with decreased urinary protein excretion, decreased cardiovascular events, and decreased all-cause mortality. Reducing nighttime BP may slow the progression of chronic kidney disease and may be the key to linking the treatment of hypertension with improved renal outcomes.