Objectives: To estimate the prevalence and incidence of type 2 diabetes among American Indian youth.
Study design: Medical records were reviewed annually for all patients with diabetes who were <20 years of age at 6 Indian Health Service facilities in Montana and Wyoming. All cases < or =5 years of age or weight per age < or =10th percentile at diagnosis or with islet cell antibodies were considered as probable type 1. Among the remaining cases, probable type 2 diabetes was defined when a child had one or more of the following characteristics: weight per age > or =95th percentile or acanthosis nigricans at diagnosis, elevated C-peptide or insulin, family history of type 2 diabetes; treatment with oral agents with or without insulin or no hypoglycemic therapy after 1 year of follow-up.
Results: From 1999 to 2001, 53% of prevalent cases and 70% of incident cases were categorized as probable type 2 diabetes. The average annual prevalence of probable type 1 and type 2 diabetes was 0.7 and 1.3 per 1000. The average annual incidence rates for probable type 1, and type 2 diabetes were 5.8, 23.3 per 100,000.
Conclusions: The incidence of probable type 2 diabetes was approximately 4 times higher than type 1 diabetes among American Indian youth in Montana and Wyoming