Endocrine Abstracts

JOINT127

Introduction: Childhood obesity has become a prevalent global health concern, affecting 25% of 10-year-olds in Leicestershire, UK. Understanding the development of obesity is crucial for identifying key predictors and groups at risk. In this study, we aimed to find distinct developmental trajectories of body mass index (BMI) and explore potential risk factors in a large, population-based pediatric cohort.

Methods: We used data from the Leicester Respiratory Cohorts (LRC), recruited in 1990 and 1998 as random samples of all 1-4 year old children living in Leicestershire UK. We calculated BMI using height and weight measurements from routine health care visits, study visits, and questionnaires, excluding extreme values with a z-score <-5 or >5, based on UK growth charts. Participants with at least 3 BMI values between 0-18 years were included. We used B-Splines to find a parsimonious pattern of BMI over age in the single class model. We then used Group Based Trajectory Modelling to identify the presence of distinct BMI trajectories, selecting the best model based on Bayesian Information Criterion, class size, average posterior probabilities, entropy, and biological plausibility. We employed multinomial logistic regression to identify factors associated with each BMI trajectory.

Results: Out of the 10, 350 children in the LRC, we included 5523 eligible children (52% boys). The best single class BMI pattern were quadratic B-Splines with two knots at 0.6 years and 9.7 years. We found 5 BMI development trajectories: normal (n = 2699, 49%), below normal (n = 1494, 27%), early overweight resolving (n = 576, 10%), school-age onset obesity (n = 217, 4%), and adolescent onset overweight (n = 537, 10%). Compared to boys, girls were more likely to be in the below normal (OR: 1.65, CI95%: 1.45-1.87), school-age onset obesity (1.48, 1.12-1.95), and adolescent onset overweight (1.48, 1.23-1.78) trajectories. Children of Asian ethnicity, compared to European, had higher odds of being in the below normal (2.75, 2.39-3.17), school-age onset obesity (1.68, 1.23-2.28), and adolescent onset overweight (1.41, 1.14-1.75) trajectories, but lower odds of being in the early overweight resolving (0.68, 0.53-0.87) trajectory. Children in the lowest tertile of socioeconomic status were more likely to be in the below normal (1.65, 1.39-1.95) and school-age onset obesity (1.80, 1.21-2.68) trajectories, compared to children in the highest tertile.

Conclusion: We identified five distinct BMI developmental trajectories and found that female sex, Asian ethnicity, and low socio-economic status were associated with specific trajectories. Targeted interventions should focus on these high-risk groups to prevent obesity and related health issues.