OR28-07 Negative Impact of Childhood Obesity and Type 2 Diabetes (T2D) on Bone Accrual and Strength: A Longitudinal Study

Abstract Disclosure: F. Bacha: None. P. Saha: None. R. Villareal: None. S. Musaad: None. R. Shypailo: None. M. Puyau: None. X. Zhang: None. Y. Mirabile: None. The impact of childhood obesity and youth-onset T2D on skeletal health (bone quality and strength) is not clear. We examined the longitudinal changes in bone microarchitecture (quality and strength) in youth across the glycemia spectrum. 48 adolescents (26 females); mean age 15.51 ± 1.33, 27% normal weight (NW), 31% overweight-normal glucose tolerance (OW), 42% OW-impaired glucose regulation (IGR) including prediabetes (n=4) or T2D (n=16), underwent baseline measurement of anthropometrics, body composition (DXA), cardiorespiratory fitness (VO2max), glucose tolerance test with glycemia and insulin indices; bone microarchitecture (HRpQCT) at the distal tibia and radius was measured at baseline (n=48), 6 month [Time 1 (T1)] (n=36) and 12 month (T2) (n=29). We examined longitudinal changes in bone quality and strength among the 3 subject categories, using generalized linear mixed models accounting for repeated subject data, adjusted for age, sex, baseline lean mass, fat mass, VO2max, HbA1c, fasting insulin, subject category, time and time by category interaction. At the tibia, there was a time by category interaction for tibia volumetric (v) BMD with estimate± SEM of -10.97±6.1, p=0.08 for IGR vs. NW and -13.34±6.1, p=0.04 for OW vs. NW, at T2 vs. baseline. Similarly, there was a negative time per category interaction for trabecular (Tb) inner BMD (-10.36±5.5, p=0.068), and Tb transverse BMD (-5.5±2.5, p=0.033) in IGR vs. NW; and for whole bone modulus (-222.47±115.30, p=0.06) in OW vs. NW, at T2 vs. baseline. Baseline fasting insulin contributed negatively to tibial whole bone modulus (-12.52±7.14, p=0.087). At the radius, there was a positive effect of time on vBMD and whole bone modulus, and a time by category interaction for radius vBMD -23.7±10.9, p=0.035 in IGR vs. NW and -20.7±10.9, p=0.066 in OW vs. NW; and for whole bone modulus -390.9±179.4, p=0.035 in IGR vs. NW and -377.02±179.9, p=0.04 in OW vs. NW, at T2 vs. baseline. Our results support a negative effect of childhood obesity and T2D on bone accrual, quality and strength at both the distal tibia and radius after accounting for age, sex, lean mass, fat mass and cardiorespiratory fitness. Insulin resistance contributes to lower bone strength at the distal tibia. This raises concern about long-term bone health in youth with obesity and dysglycemia. Presentation: Monday, July 14, 2025