The 10-year incidence of renal insufficiency in people with type 1 diabetes

OBJECTIVE - To describe the 10-year decrease in estimated creatinine clearance and the incidence of renal insufficiency and end-stage renal disease in a cohort of people with type 1 diabetes. RESEARCH DESIGN AND METHODS - A population-based cohort of individuals with younger-onset diabetes (diagnosed at <30 years old and taking insulin) participated in an examination during 1984-1986 (n = 891), a 6-year follow-up examination during 1990-1992 (n = 765), and a 10-year follow-up examination during 1995-1996 (n = 634). Serum creatinine and risk factors were measured using standardized protocols at each examination. Estimated adjusted creatinine clearance was computed by a modification of the Cockroft-Gault formula. A clinically meaningful change was defined as a decrease in the estimated annual creatinine clearance of greater than or equal to 3 ml . min(-1) . 1.73 m(-2) . year(-1). Renal insufficiency was defined by the development of a serum creatinine of 2.0 mg/dl or greater after the 1984-1986 examination. RESULTS - The 10-year estimated incidence of an annual decrease in the creatinine clearance of greater than or equal to 3 ml . min(-1) . 1.73 m(-2) for the cohort was 52.5%, and the cumulative 10-year incidence of renal insufficiency and end-stage renal failure was 14.4%. In univariate analyses, incidence of a decrease in the estimated creatinine clearance of greater than or equal to 3 ml . min(-1) . 1.73 m(-2) . year(-1) and the incidence of renal insufficiency were both related to higher glycosylated hemoglobin; higher diastolic blood pressure; the presence of microalbuminuria and gross proteinuria; more severe retinopathy; and a history of loss of tactile sensation or temperature sensitivity at baseline. In logistic regression analysis, after adjusting for the presence of microalbuminuria and gross proteinuria at baseline, higher glycosylated hemoglobin and higher diastolic blood pressure were associated with decreasing estimated creatinine clearance. In logistic regression analyses, after adjusting for the presence of microalbuminuria and gross proteinuria at baseline, the incidence of renal insufficiency was independently associated with age, glycosylated hemoglobin, hypertension, and serum HDL cholesterol. CONCLUSIONS - These data suggest that a public health approach aimed at controlling glycemia, blood pressure, and serum lipids might result in reducing the rate of decline in renal function and development of renal insufficiency in people with type 1 diabetes.