Identification of Heterogeneous Cortical Thickness Patterns Associated with Prenatal Gestational Diabetes Exposure: A SuStaIn-Based Subtyping Study

ImportancePrenatal exposure to gestational diabetes mellitus (GDM) has been associated with adverse metabolic, neurodevelopmental, and psychiatric outcomes in offspring. However, whether GDM-exposed youth exhibit heterogeneous neuroanatomical patterns remains unclear. ObjectiveTo identify distinct cortical thickness subtypes among GDM-exposed youth and examine their associations with anthropometric, neurocognitive, psychiatric/behavioral and neuroimaging measures both cross-sectionally and longitudinally. Design, Setting, and ParticipantsThis cohort study used the Adolescent Brain Cognitive Development (ABCD)(R)data, a multisite longitudinal population study. Subtype and Stage Inference (SuStaIn), an unsupervised machine learning framework, was applied to cross-sectional structural MRI data to identify cortical thickness patterns in 573 GDM-exposed youth and 2854 healthy controls. Posthoc longitudinal analyses included 1,853 observations from a subset of GDM-exposed youth with 1-, 2-, and 4-year follow-up visits to examine subtype differences in developmental trajectories over time. Exposure(s)Prenatal exposure to GDM. Main Outcome(s) and Measure(s)The primary outcomes included identification of cortical thickness subtypes and their inferred regional ordering patterns. Secondary outcomes included subtype-specific anthropometric, neurocognitive, psychiatric/behavioral and neuroimaging measures. ResultsThe GDM-exposed sample had a mean age of 119.02 {+/-} 7.34 months and was 47.5% female. Two cortical thickness subtypes were identified. Between subtypes, Subtype 1 (63.2%) was characterized by earlier inferred insula involvement and was associated with greater height (d = 0.36, pFDR < 0.001) and weight (d = 0.26, pFDR = 0.007), whereas Subtype 2 exhibited earlier inferred frontal involvement and nominally higher Attention-Deficit/Hyperactivity Disorder (ADHD) prevalence (d = 0.08, p = 0.036), steeper longitudinal cortical thinning across all six cortical regions of interest ({beta} range: -0.05 to -0.13, all pFDR < 0.05), and a smaller decline in Obsessive-Compulsive Disorder (OCD) prevalence over time ({beta} = -1.02, pFDR = 0.049). Conclusions and RelevanceGDM exposure was associated with two distinct offspring cortical thickness subtypes, each showing different inferred regional ordering patterns and clinical associations. One subtype showed an insula-cingulate-predominant pattern associated with anthropometric measures, whereas the other showed a frontal-predominant pattern associated with nominally higher psychiatric measures and faster cortical thinning over time.