The association of time-updated ambulatory blood pressure and renal progression in hypertensive patients with chronic kidney disease: post hoc analysis of ACCURATE study

Objectives: : This study aimed to evaluate the effect of time-updated ambulatory blood pressure on chronic kidney disease (CKD) progression in patients with hypertension.

Methods: : Among patients with hypertension and CKD stages 3 and 4, enrolled in a clinical trial in which hypertension was treated based on office or ambulatory blood pressure (BP), participants assigned to the ambulatory BP were included in this study. Ambulatory BP was measured at the start of the study and 3, 6, and 18 months. Renal events were defined as a decrease in the estimated glomerular filtration rate (eGFR) by at least 30%, dialysis, or transplantation.

Results: : A total of 21 cases of renal events were observed. For baseline BP, a multivariate Cox model revealed that neither office SBP nor any component of ambulatory SBP, including mean, day-time, night-time BPs was associated with the risk of renal events. For time-updated BP, a marginal structural model revealed that the office SBP was not associated with renal events [hazard ratio 1.03, 95% confidence interval (CI) 0.99-1.07, P = 0.117], but higher ambulatory SBPs, including day-time (hazard ratio 1.05, 95% CI 1.01-1.10, P = 0.014), night-time (hazard ratio 1.05, 95% CI 1.02-1.08, P = 0.001), and mean (hazard ratio 1.06, 95% CI 1.02-1.10, P = 0.002) ambulatory SBPs, were significantly associated with an increased risk of renal events.

Conclusion: : A higher time-updated ambulatory BP was associated with an increased risk of renal events in patients with hypertension and CKD, whereas baseline office and ambulatory BP, and time-updated office BP were not.