Cumulative blood pressure load as a predictor of arterial stiffness progression and incident diabetic kidney disease: a multicenter longitudinal study.

Background: Elevated blood pressure (BP) is a key contributor to the progression of arterial stiffness and the incidence of diabetic kidney disease (DKD). Cumulative BP load enables the evaluation of long-term BP exposure, but the BP targets used to calculate it vary across studies. This study aimed to compare the predictive performance of cumulative BP load calculated using different clinically recommended BP targets.

Methods: This multicenter longitudinal study included participants with type 2 diabetes from 10 diabetes centers. Cumulative BP load was calculated using various clinically recommended BP targets (SBP < 140 mmHg, < 130 mmHg, and < 120 mmHg). The primary outcomes were the progression of arterial stiffness, assessed by brachial-ankle pulse wave velocity (ba-PWV) changes, and the incidence of DKD, defined as an estimated glomerular filtration rate < 60 mL/min/1.73m² or urine albumin-to-creatinine ratio ≥ 3.39 mg/mmol. The predictive ability of cumulative BP load calculated under different clinically recommended targets was compared using adjusted R squared (adjusted R²) for continuous outcomes and net reclassification improvement (NRI) for binary outcomes.

Results: Among the 18,168 participants included (mean age 54.5 years; 57.5% male), 13,388 met all eligibility criteria for the analysis of arterial stiffness progression, and 11,145 for the analysis of DKD incidence. Over a mean follow-up of 3.5 years, the median ba-PWV increase was 0.19 m/s per year and 2,855 (25.6%) developed DKD. When cumulative BP load was added to a model containing traditional risk factors, the adjusted R² values for predicting the absolute annual change in ba-PWV were 0.193 (95% CI 0.180-0.200), 0.184 (0.169-0.191), and 0.172 (0.158-0.180) with BP targets of SBP < 120, < 130, and < 140 mmHg, respectively. For the incidence of DKD, the NRIs were 15.8% (11.5-20.0%), 12.5% (8.3-16.7%), and 6.4% (2.3-10.6%) with BP targets of SBP < 120, < 130, and < 140 mmHg, respectively.

Conclusion: Cumulative BP load is an effective indicator for predicting the progression of arterial stiffness and incidence of DKD, with the best predictive performance observed when the target SBP is set at < 120 mmHg.