SAT348 Changes In BMI Z-score After Presentation For Early Breast Budding Is Associated With Rapidly Progressive Puberty And Treatment With GnRH Analogues

Disclosure: H. Jung: None. J. Cho: None. K. Shim: None. Introduction: Childhood overweight and obesity are associated with earlier pubertal timing, especially in girls. We aimed to identify different body mass index (BMI) trajectories in patients presenting for breast budding between 5 and 7 years of age, and investigated whether the change in BMI z-scores during follow up is associated with rapid progression of puberty and eventual treatment with gonadotropin-releasing hormone (GnRH) analogues. Methods: We retrospectively reviewed girls who presented with breast budding at 5 to 7 years of age, between March 2016 and May 2021 at a single center. Those 206 girls, who had more than 3 follow up BMI measurements to more than 9 years of age were included in the study. The girls were grouped according to whether BMI z-scores increased or decreased/remain unchanged overall during follow-up. The BMI z-score changes over time (age) were also assessed for latent class trajectories. The risk of progression to rapid progressive puberty requiring treatment with GnRH analogues was analyzed according to overall changes in BMI z-scores and the different BMI trajectory groups, with adjustment for birthweight, gestational age, maternal menarche, maternal height, as well as the initial age, height, and bone age at presentation. Results: The mean age at presentation for breast budding was 7.1±0.7 years. A greater proportion of girls whose BMI z-scores increased during follow up, required treatment with GnRH analogues (n=53, 64%) compared to those whose BMI z-scores decreased or remained unchanged (n=54, 44%). Girls with increases in BMI z-scores during follow up (n=83) had increased risk (OR 4.68, 95% CI 1.88-11.63, p = 0.001) for rapid progressive puberty and treatment with GnRH analogues compared to those girls with decreases/no changes (n=123) in BMI z-scores, even after adjustment for covariates. Further analysis showed that increases in BMI z-scores even in those of normal weight status, were associated with increased OR (4.88) for treatment. Through latent class mixed modelling analysis, we identified 2 different trajectories (high and increasing BMI z-scores, n=72; and decreasing BMI z-scores, n=134). Risk for rapid progression of puberty and eventual treatment with GnRH analogues did not differ significantly between the different latent class trajectories. Conclusions: Increases in BMI z-scores during the follow up period after presentation for early breast budding may be associated with increased risk for rapid progression of puberty and treatment with GnRH analogues. Analysis of a larger group of patients may allow for better assessment of latent class BMI z-score trajectories. Presentation: Saturday, June 17, 2023