Mild renal insufficiency as a cardiovascular risk factor in non-proteinuric type II diabetes

Objectives: To evaluate cardiovascular risk according to baseline renal function in a group of non-proteinuric type II diabetic patients. Material and methods: Prospective study with a follow-up of 423 non-proteinuric type II diabetic patients with creatinine < 150 mumol/l for an average of 4.7 years (S.D. 1.55). Creatinine clearance (CC) was estimated using the Cockcroft-Gault formula and expressed in millilitre per minute. The hazard ratio (HR) associated with each millilitre per minute decrease in baseline CC on fatal or non-fatal cardiovascular events and total mortality was evaluated using the Cox regression model. Results: Baseline creatinine was 89 mumol/l (S.D. 15.9) and CC was 69.5 ml/min (S.D. 20). There were 63 cardiovascular events (15 unstable angina, 10 non-fatal myocardial infarctions, 25 non-fatal strokes, two amputations, nine fatal myocardial infarctions and two fatal strokes) and 39 total deaths (11 for cardiovascular causes). The cardiovascular event rate was 31.7/1000 patient-years and the total mortality rate was 19.6/1000 patient-years. The independent predictors of cardiovascular events were: CC (HR = 1.035; confidence interval (CI) 95% 1.02-1.05; P < 0.0001), total cholesterol/HDL cholesterol ratio (HR = 1.25; CI 95% 1.1-1.4; P = 0.0008), baseline coronary heart disease (HR = 2.05; CI 95% 1.07-3.9; P = 0.04) and baseline microalbuminuria (HR = 2.3; CI 95% 1.3-3.8; P = 0.003). The independent total mortality predictors were: CC (HR = 1.04; CI 95% 1.02-1.08; P < 0.0001), male (HR = 2.1; CI 95% 1.1-4;P = 0.027) and baseline microalbuminuria (HR = 2.1; CI 95% 1.1-4;P = 0.03). Conclusions: Mild renal insufficiency increases cardiovascular risk in non-proteinuric patients with type 11 diabetes. (C) 2003 Elsevier Ireland Ltd. All rights reserved.