The Journal of clinical endocrinology and metabolism | 2021
Associations of Body Mass Index and Waist Circumference in Young Adulthood with Later Life Incident Diabetes.
Abstract
CONTEXT\nThe independent contribution of young adult exposure to overweight and obesity to later life incident diabetes is not well studied.\n\n\nOBJECTIVE\nTo assess the associations of exposures to elevated body mass index (BMI) and waist circumference (WC) in young adulthood (ages 18 to 39 years) with incident diabetes later in life (≥40 years).\n\n\nDESIGN\nPooled data from six US prospective cohorts (ARIC, CARDIA, CHS, Framingham Offspring, Health ABC, MESA).\n\n\nSETTING\nPopulation-based cohort studies.\n\n\nPARTICIPANTS\n30,780 participants (56.1% female, 69.8% non-Hispanic White) without a diagnosis of diabetes by age 40.\n\n\nINTERVENTIONS\nWe imputed BMI and WC trajectories from age 18 for every participant and estimated time-weighted average exposures to BMI or WC during young adulthood and later life.\n\n\nMAIN OUTCOME MEASURE(S)\nIncident diabetes defined as fasting glucose ≥126\xa0mg/dL, non-fasting glucose ≥200\xa0mg/dL, or use of diabetes medications.\n\n\nRESULTS\nDuring a 9-year median follow-up, 4,323 participants developed incident diabetes. Young adult BMI and WC were associated with later life incident diabetes after controlling for later life exposures (hazard ratios [HR] 1.99 for BMI ≥30\xa0kg/m 2 and 2.13 for WC >88cm [women]/>102cm [men] compared to normal ranges). Young adult homeostatic model of insulin resistance (HOMA-IR) mediated 49% and 44% of the association between BMI and WC with later life incident diabetes. HDL and triglycerides mediated a smaller proportion of these associations.\n\n\nCONCLUSIONS\nElevated BMI and WC during young adulthood were independently associated with later life incident diabetes. Insulin resistance appears to be a key mediator.