Prevalence of obesity in people with and without type 1 diabetes across Belgium, Kuwait, and Mexico: an IMI2 SOPHIA study

Background Individuals with type 1 diabetes (T1D) are traditionally perceived as lean, but recent evidence suggests an increasing trend of obesity. To provide global estimates, this study explored the prevalence of obesity among adults with and without T1D across three distinct global regions. Methods An observational, cross-sectional study was performed utilizing data from T1D registries and national health surveys to assess the prevalence of obesity (BMI >= 30 kg/m(2)) and the prevalence of overweight and obesity (BMI >= 25 kg/m(2)) across Belgium, Kuwait, and Mexico. Demographic and clinical characteristics of adults with and without T1D were assessed. Prevalence estimates were calculated through a binomial generalized linear mixed-effects model adjusting for age, sex, HbA1c, and survey year. As a sensitivity analysis, propensity score matching was performed for confounder adjustment of age and sex. Findings The study encompassed 3594 individuals with T1D (from 2003 to 2022) and 9898 without T1D (from 2014 to 2021). After model adjustment for confounders (age, sex, HbA1c% and data-collection year), individual obesity prevalence was lower in individuals with T1D in Kuwait and Mexico than among those without type 1 diabetes (Kuwait: 22% (CI: 18-26%) vs. 44% (CI: 41-48%); Mexico: 5% (CI: 3-7%) vs. 40% (CI: 38-42%)). In contrast, individuals with T1D in Belgium showed a more comparable proportions to those without T1D (12% (CI: 9-16%) vs. 16% (CI:11-22%)). Interpretation Our data reveal that obesity is prevalent among people with T1D. These findings underscore the need for targeted strategies in T1D care that address the growing concern of obesity.