Increasing incidence of early-onset type 2 diabetes in Sweden 2006–2021

Our aim was to provide new data on the incidence, prevalence, and secular trend of type 2 diabetes (T2D) in Sweden, specifically early-onset T2D. We followed the Swedish population 2006 to 2021 and calculated age-standardized incidence (per 100 000) and prevalence (%) of T2D (overall) and early-onset T2D (age 23-39 years) stratified by sex, region of birth, and educational level. We projected the future prevalence of early-onset T2D by combining observed trends with population projections. From 2006 to 2021, the prevalence of T2D rose from 4.87% to 7.50%, and incidence from 477 [95% confidence interval (CI) 471-482] to 574 (CI 568-579). Early-onset T2D incidence increased from 54 to 107 (4.7% annual rise; CI 3.7%-5.7%) during this period. Incidence of early-onset T2D was higher in individuals born outside Europe (211, CI 195-226 vs 89, CI 84-93 in 2021) or low education (204, CI 185-223 vs 71, CI 65-77 in 2021), but a rise in incidence was seen irrespective of educational level, region of origin, and sex. If the incidence of early-onset T2D continues to increase at the same pace, its prevalence is projected to increase from 0.64% in 2021 to 3.2% in 2050. While T2D incidence rose marginally in Sweden 2006 to 2021, there was a significant rise in early-onset T2D, seen across different socioeconomic characteristics, with prevalence more than doubling and incidence nearly doubling. This development calls for targeted preventive efforts.