Impaired kidney function and the risk of all-cause mortality and cardiovascular disease among Chinese hypertensive adults: Using three different equations to estimate the glomerular filtration rate

Objectives: We aimed to seek accurate assessments of the glomerular filtration rate (GFR) in a Chinese hypertensive population to identify individuals at high risk for chronic kidney disease (CKD) progression. Then, the risk of cardiovascular disease (CVD) and all-cause death due to kidney injury were further investigated under appropriate GFR-estimation equations. Methods: In this prospective follow-up cohort study of 10,171 hypertensive patients, we compared the discrimination power of a trio of GFR-estimation equations using Harrell's C-index, measuring the model fit by calculating the Akaike information criterion. Univariate and multivariable logistic regression analyses were respectively used to calculate the hazard ratio (HR) and 95% confidence interval [CI] values for CKD progression. In addition, we also assessed the risk of CVD and all-cause death with impaired renal function using multivariable-adjusted Cox regression models. Results: The Modification of Diet in Renal Disease (MDRD) equation showed the highest C-index range for the predicted probability of CKD progression in the fully adjusted model. During MDRD analysis, a low eGFR (60-89 mL/min/1.73m(2) or < 60 mL/min/1.73m(2)) was an independent risk factor for CVD, especially stroke (1.28 [95% CI, 1.05-1.55] and 1.89 [95% CI, 1.08-3.31]), as well as all-cause mortality (1.28 [95% CI, 1.09-1.50] and 1.68 [95% CI, 1.01-2.78]). Conclusions: The MDRD equation seems to be more suitable for screening CKD progression in Chinese hypertensive populations, targeting potential risk factors for effective prevention to reduce renal impairment so as to further limit CVD morbidity and mortality.