Estimated glomerular filtration rate and albuminuria are independent predictors of cardiovascular events and death in type 2 diabetes mellitus: the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study

Abstract

Background We investigated effects of renal function and albuminuria on cardiovascular outcomes in 9795 low-risk patients with diabetes in the Fenofibrate Intervention and Event Lowering in Diabetes study. Methods Baseline and year 2 renal status were examined in relation to clinical and biochemical characteristics. Outcomes included total cardiovascular (CVD), cardiac and non-cardiac mortality over 5-years. Results Lower eGFR versus eGFR ≥ 90 ml min–11.73m–2 was a risk factor for total CVD events: [HR (95% CI): 1.14 (1.01–1.29) for eGFR 60–89 ml min–11.73m–2; 1.59 (1.28–1.98) for eGFR 30–59 ml min–11.73m–2; p<0.001], adjusted for other characteristics. Albuminuria increased CVD risk: microalbuminuria and macroalbuminuria increased total CVD [HR 1.25 (1.01–1.54) and 1.19 (0.76–1.85), respectively (trend p=0.001)] when eGFR ≥ 90 ml min–11.73m–2. CVD risk was further modified by renal status changes over the first 2 years. In multivariable analysis, 77% of eGFR and 81% of ACR’s effects were accounted for by other variables, principally low HDL-cholesterol and elevated blood pressure. Conclusions Reduced eGFR and albuminuria are independent risk factors for cardiovascular events and mortality in a low-risk population of mainly European ancestry. While their independent contributions to CVD risk appear small when other risk factors are considered, because they capture risk related to a number of other characteristics, they remain excellent surrogate markers in clinical practice. Therefore, both should be considered when assessing prognosis and treatment strategies in patients with diabetes, and should be included in risk models. This study was prospectively registered (ISRCTN 64783481)