Nocturnal systolic blood pressure dipping and progression of chronic kidney disease

The relationship between declining nocturnal blood pressure (BP) and adverse cardiovascular outcomes is well-recognized. However, the relationship between diurnal BP profile and the risk of chronic kidney disease (CKD) progression is unclear. Herein, we examined the association between nocturnal systolic SBP (SBP) dipping and CKD progression in 1061 participants at the Cardiovascular and Metabolic Disease Etiology Research Center-High Risk (CMERC-HI). The main exposure was diurnal systolic BP (SBP) profile and diurnal SBP difference ([nighttime SBP-daytime SBP] × 100/daytime SBP). The primary outcome was CKD progression, defined as a composite of ≥ a 50% decline in the estimated glomerular filtration rate from baseline or the initiation of kidney replacement therapy. During 4749 person-years of follow-up (median, 4.8 years), the composite outcome occurred in 380 (35.8%) participants. Compared to dippers, the hazard ratios (HRs) for the risk of adverse kidney outcomes were 1.02 (95% confidence interval [CI], 0.64-1.62), 1.30 (95% CI, 1.02-1.66), and 1.40 (95% CI, 1.03-1.90) for extreme dipper, non-dipper, and reverse dipper, respectively. In a continuous modeling, a 10% increase in diurnal SBP difference was associated with a 1.21-fold (95% CI, 1.07-1.37) higher risk of CKD progression. Thus, decreased nocturnal SBP decline was associated with adverse kidney outcomes in patients with CKD. Particularly, patients with non-dipping and reverse dipping patterns were at higher risk for CKD progression than those with a dipping pattern.