Objective: Data on the incidence of end-stage renal disease (ESRD) and chronic renal failure from population-based studies in Caucasian type 2 diabetic patients are lacking. To provide such data, a population-based cohort of type 2 diabetic patients was identified in Casale Monferrato, Italy, and prospectively examined from 1991 to 2001.
Research design and methods: During the follow-up period, patients were regularly examined with centralized measurements of plasma creatinine and HbA(1c). Independent predictors of progression to renal events were identified with multivariate Cox proportional hazards modeling, with sex, age, and individual follow-up time as confounders.
Results: We followed 1,408 of 1,540 (91.4%) patients (average follow-up time 6.7 years, range 0.011-11.1); 10 new cases of ESRD and 72 of chronic renal failure (plasma values of creatinine >or=2.0 mg/dl) were identified, giving incidence rates/1,000 person-years of 1.04 (95% CI 0.56-1.94) and 7.63 (6.06-9.61), respectively. Cumulative risks for chronic renal failure adjusted for competing mortality were 6.1 and 9.3% after 20 and 30 years from diagnosis of diabetes, respectively. Incidence rates and cumulative risks of chronic renal failure defined by plasma creatinine values >1.5 mg/dl increased to 13.1/1,000 person-years, 8.6 and 14.8%, respectively. In Cox regression analysis, predictors of progression (after adjustment for confounders) were hypertension (P = 0.078), diastolic blood pressure (P = 0.034), BMI (P = 0.03), and albumin excretion rate (AER) (P < 0.0001).
Conclusions: We provide evidence that the individual risk of ESRD and chronic renal failure is low. AER and diastolic blood pressure are independent predictors of progression. These findings underline the relevance of primary prevention to reduce the number of diabetic patients with ESRD.