Increasing Incidence of Type 1 Diabetes in 0- to 17-Year-Old Colorado Youth

Abstract

OBJECTIVE—We sought to assess the long-term trends in the incidence of type 1 diabetes among non-Hispanic white and Hispanic youth aged 0–17 years from Colorado using data from the Colorado IDDM Study Registry (1978–1988) and SEARCH for Diabetes in Youth (2002–2004). RESEARCH DESIGN AND METHODS—Cases of diabetes were ascertained through physician reporting and hospital databases. Type 1 diabetes was defined as use of insulin within 2 weeks from diagnosis. Completeness of ascertainment was estimated as 97%. Annual average incidence rates (per 100,000/year) and 95% CIs for the time periods were computed. Trends in incidence were assessed by Poisson regression. RESULTS—The incidence of type 1 diabetes was 14.8 (95% CI 14.0–15.6) in 1978–1988 and 23.9 (22.2–25.6) in 2002–2004 for the state of Colorado (P < 0.0001). From 1978 to 2004, the incidence of type 1 diabetes increased by 2.3% (1.6–3.1) per year (P < 0.0001). The increase in incidence was significant for both non-Hispanic white (2.7% [95% CI 1.9–3.6] per year, P < 0.0001) and Hispanic youth (1.6% [0.2–3.1] per year, P = 0.013). CONCLUSIONS—The incidence of type 1 diabetes has increased 1.6-fold among Colorado youth from 1978–1988 to 2002–2004, and both non-Hispanic white and Hispanic youth are affected by this trend.