Greater radiologic evidence of hypothalamic gliosis predicts adiposity gain in children at risk for obesity

Abstract

Objective: This study investigated, in a large pediatric population, whether magnetic resonance imaging (MRI) evidence of mediobasal hypothalamic (MBH) gliosis is associated with baseline or change over 1 year in body adiposity. Methods: Cross-sectional and prospective cohort analyses were conducted within the Adolescent Brain Cognitive Development Study. Study 1 included 169 children with usable baseline T2-weighted MRI images and anthropometrics from baseline and 1-year follow-up study visits. Signal ratios compared T2 signal intensity in MBH and two reference regions (amygdala [AMY] and putamen) as a measure of MBH gliosis. Study 2 included a distinct group of 238 children with overweight or obesity to confirm initial findings in an independent sample. Results: In Study 1, MBH/AMY signal ratio was positively associated with BMI z score (β = 4.27, p < 0.001). A significant interaction for the association of MBH/AMY signal ratio with change in BMI z score suggested that relationships differed by baseline weight status. Study 2 found that higher MBH/AMY signal ratios associated with an increase in BMI z score for children with overweight (β = 0.58, p = 0.01), but not those with obesity (β = 0.02, p = 0.91). Conclusions: Greater evidence of hypothalamic gliosis by MRI is associated with baseline BMI z score and predicts adiposity gain in young children at risk of obesity.