1266-P: Puberty Is Associated with a Rising HbA1c, Even in Healthy Normal Weight Youth

Abstract

Objective: ADA definitions of prediabetes are applied to children, yet little is known about the impact of the transient insulin resistance of puberty on glycemia. We aimed to evaluate the longitudinal trajectory of hemoglobin A1c (HbA1c) in youth with normal weight and with obesity as they progressed through puberty. Methods: Youth with normal weight (n=47, 49% female) or obesity (n=37, 62% female) of mixed race/ethnicity (Non-Hispanic White 34%, Hispanic 45%, Non-Hispanic Black 13%) entered the study in Tanner stage 2-3 (T2-3) and were followed until T5. Study visits were done at T2-3, T4, and T5 and included an IV glucose tolerance test, DXA, and fasting laboratory studies. HbA1c was measured by high-performance liquid chromatography and insulin sensitivity (Si), acute insulin response to glucose (AIRg), and disposition index (DI) were calculated. Group differences in HbA1c over time and time-dependent predictors of HbA1c were evaluated by mixed models, with and without adjusting for sex, race/ethnicity, and DXA %Fat. Results: Mean HbA1c was higher in youth with obesity (5.30±0.08%) vs. normal weight (5.10±0.06%, p=0.04) at baseline and each subsequent time point; differences were attenuated by adjusting for %Fat. HbA1c increased from T2/3 to T5 in the whole cohort (0.16±0.05%, p=0.004), and in youth with obesity (+0.18±0.08%, p=0.08), or normal weight (+0.14±0.05%, p=0.02); findings were similar after adjusting for sex, race/ethnicity, and %Fat. In a multivariate model adjusted for sex and race/ethnicity, HbA1c was associated with leptin (β=0.005, p=0.01) and adiponectin (β=-0.01p=0.02); these associations are similar after adjusting for %Fat. HbA1c was not associated with Si, AIRg or DI. Conclusions: Obesity is associated with higher HbA1c than normal weight during puberty. However, HbA1c increased during puberty, independent of body weight and composition. This increase in HbA1c is associated with changes in adipokines, but not with typical predictors of progression to diabetes (Si, DI). Disclosure M.M. Kelsey: Other Relationship; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Daiichi Sankyo, Janssen Pharmaceuticals, Inc., Merck Sharp & Dohme Corp. A.M. Hilkin: None. C. Severn: None. L. Pyle: None. K.J. Nadeau: None. P. Zeitler: Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Daiichi Sankyo, Eli Lilly and Company, Merck & Co., Inc. Funding American Diabetes Association (1-11-JF-23 to M.M.K.); Eunice Kennedy Shriver National Institute of Child Health and Human Development (HD057022-04); University of Colorado Center for Women’s Health Research; Children’s Hospital Colorado Research Institute; National Institute for Diabetes and Digestive and Kidney Diseases (DK048520-13); National Center for Advancing Translational Sciences (UL1TR001082)