Ambulatory blood pressure monitoring-based analysis of long-term outcomes for kidney disease progression

Non-dipping nocturnal blood pressure (BP) pattern is a predictor of the future decline of renal function; however, it is unclear whether it is still a risk for chronic kidney disease (CKD) patients with normal BP. To solve this question, a retrospective cohort study was conducted, and 1107 CKD patients who underwent ambulatory blood pressure monitoring (ABPM) were enrolled. We divided patients into 4 groups based on their nocturnal BP dipping pattern (dipper or non-dipper) and average 24-hour BP (hypertension or normotension). The cumulative incidence of composite renal outcomes, including a 40% reduction in eGFR, the induction of renal-replacement therapy, or death from renal causes, was analyzed. Overall, 86.1% of participants were non-dippers and 48.2% of them were normotensive. During the median follow-up period of 4.72 years, the incidence of renal composite outcomes was highest in hypertensive non-dipper patients, and was similar between normotensive dipper and non-dipper patients. Multivariate regression analysis revealed that the 24-hour systolic BP, amount of urinary protein, and hemoglobin values were associated with the incidence of renal outcomes. In conclusion, our ABPM-based analysis revealed that a non-dipping BP pattern with normotension does not predict the future incidence of composite renal outcomes in CKD patients.