ABSTRACT
BACKGROUND: There is uncertainty regarding the role of obesity in type 1 diabetes development. The aim of this systematic review and meta-analysis was to collect and synthesize evidence regarding BMI and the risk of developing type 1 diabetes. METHODS: A systematic review and meta-analysis were conducted to assess the association between BMI and incident type 1 diabetes. Databases were searched up to June 2022. Cohort studies were included reporting the association between overweight and/or obesity, as measured by BMI after age 2 years, with incident type 1 diabetes. Independent reviewers extracted data and assessed study quality. Risk estimates were pooled using a random-effects model. RESULTS: Ten cohort studies met the inclusion criteria. The seven studies that classified BMI into categories were of high quality and involved 1,690,660 individuals and 1979 incident type 1 diabetes cases. The pooled risk ratio (RR) for type 1 diabetes was 1.35 (95% CI 0.93-1.97) among people with overweight (3 studies); 2.17 (95% CI 1.75-2.69) among people with obesity (5 studies); and 1·87 (95% CI 1.52-2.29) among people with overweight/obesity (two studies merged the categories). These point estimates persisted in sensitivity analyses that addressed the duration of follow-up, variability in baseline risk for incident type 1 diabetes, and potential misclassifications related to exposure or outcome definitions. People with overweight/obesity had a 2.55 (95% CI 1.11-5.86) greater risk for incident type 1 diabetes with positive islet autoantibodies. CONCLUSION: This systematic review and meta-analysis of high-quality observational cohort studies indicated an association between high BMI and the risk of type 1 diabetes, in a graded manner.
Subject(s)
Diabetes Mellitus, Type 1 , Overweight , Humans , Child, Preschool , Overweight/diagnosis , Overweight/epidemiology , Diabetes Mellitus, Type 1/diagnosis , Diabetes Mellitus, Type 1/epidemiology , Body Mass Index , Obesity/diagnosis , Obesity/epidemiology , Cohort StudiesABSTRACT
PURPOSE OF REVIEW: Type-2 diabetes (T2D) in children and adolescents has become an increasingly important public health concern, currently accounting for nearly half of all diabetes cases in this age group in some countries. With immigration growing worldwide, immigrants as a subpopulation warrant special attention. Although the association of immigration and T2D has been explored in older persons, few studies have examined it in adolescent immigrants. RECENT FINDINGS: Of 64 studies, only 8 were relevant and elaborated on in this review. Our findings show that adolescent immigrants to Western countries seem to benefit an overall favorable metabolic profile that is associated with lower odds to dysmetabolism. However, this protective effect wanes over time with longer years of residency and plateaus at approximately a decade from arrival. As immigration becomes a global phenomenon, pediatric T2D in these special populations has major public health and socioeconomic implications. Improving immigrants' access to healthcare, healthcare education and utilization, and specific cultural programs for prevention and treatment of T2D are important to ensure the accessibility of preventive medical services to young immigrants. Further research should be considered to help identify at-risk youth.
