Trends in Type 1 diabetes incidence in the UK in 0- to 14-year-olds and in 15- to 34-year-olds, 1991-2008.

AIM: To describe Type 1 diabetes incidence trends in the UK between 1991 and 2008 in children aged 0-14 years and in young adults aged 15-34 years.

METHODS: Data from the UK General Practice Research Database were analysed, including 3002 individuals (1565 aged 0-14 years and 1437 aged 15-34 years) newly diagnosed with Type 1 diabetes. Poisson regression was used to model annual incidence increases and seasonality effects.

RESULTS: Type 1 diabetes incidence increased from 11 to 24/100,000 person-years in boys and from 15 to 20/100,000 person-years in girls. In adults, the incidence rate increased from 13 to 20/100,000 person-years (men) and from 7 to 10/100,000 person-years (women). Annual incidence increases tended to be greater in children (4.1%, 95% CI 3.0-5.2%) compared with 15- to 34-year-olds (2.8%, 95% CI 1.6-3.9%). There was evidence of higher incidence rates during autumn and winter in children, but not in adults.

CONCLUSIONS: A continuing increase in Type 1 diabetes incidence was shown that was greater in children than in young adults. Seasonal variation was observed in children only.