Kidney failure risk in type 1 vs. type 2 childhood-onset diabetes mellitus.

BACKGROUND: Diabetic kidney disease (DKD) is becoming increasingly common among children. We aimed to estimate the risk of end-stage renal disease (ESKD) and mortality among adolescents with type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM) and normal renal function compared with non-diabetics. We hypothesized that childhood onset T1DM vs. T2DM would be associated with a different risk profile for developing ESKD and its complications. METHODS: A nationwide, population-based, retrospective cohort study, including 1,500,522 adolescents examined for military service between 1967 and 1997, which were classified according to the presence and type of diabetes. Data were linked to the Israeli ESKD registry. Cox proportional-hazards models were used to estimate the hazard ratio (HR) for ESKD. RESULTS: At study enrolment, 1183 adolescents had T1DM and 196 had T2DM. ESKD developed in 2386 non-diabetic individuals (0.2%) compared with 72 individuals (6.1%) with T1DM and 8 individuals (4.1%) with T2DM. Participants with T1DM were younger at ESKD onset than participants with T2DM (median age, 36.0 vs. 40.5 years, P < 0.05). In a multivariate model adjusted for age, sex, paternal origin, enrollment year, BMI, and blood pressure, T1DM and T2DM were associated with HR of 36.4 (95% CI 28.3-46.9) and 19.3 (95% CI 9.6-38.8) for ESKD, respectively. Stratification according to sex, ethnicity, immigration, and socioeconomic status did not materially change the HR. During the follow-up period, mortality rates were higher in T2DM as compared with T1DM and controls (8.7 %, 2.2%, and 2.7% respectively). CONCLUSIONS: T1DM and T2DM in adolescents with normal renal function confer a significantly increased risk for ESKD. T1DM is associated with younger age at ESKD onset while T2DM is associated with higher mortality rate.