Distinct Structural Alterations in Cortical and Subcortical Regions in Females With Acute Anorexia Nervosa: A Cross-Sectional MRI Study With BMI-Matched Healthy Controls

Abstract

Objective: This study aimed to explore potential disease-specific and weight-related neurostructural alterations in patients with acute anorexia nervosa (AN). Method: Employing a novel BMI-matched design, structural MRI data were collected from 36 females with AN, 35 normal-weight healthy controls (NHC), and 29 underweight healthy controls (UHC). Cortical (thickness, surface area) and subcortical (volume) morphometry measures were computed via FreeSurfer. Group differences were tested using generalized linear models, with associations examined for BMI, symptom severity, and weight suppression (lifetime highest minus current weight). Results: Compared with UHC, AN patients exhibited subcortical volume reductions in the bilateral pallidum and caudate, left putamen, and right thalamus, as well as cortical thinning in default mode network regions (bilateral inferior parietal lobule, right precuneus, posterior cingulate cortex) and the left cuneus, indicating potential disease-specific alterations. Comparisons between UHC and NHC revealed BMI-related alterations, reflected in surface area reductions of the right orbitofrontal cortex and left insula, and in volume reductions of the bilateral amygdala, right hippocampus, and left thalamus. Within AN, weight suppression was negatively associated with cortical thickness across 44 regions, suggesting a possible link with prior weight loss. Conclusions: By including BMI-matched healthy control groups, this study provides preliminary evidence for distinguishing disease-specific from BMI-related neurostructural alterations in patients with AN. Future research may help clarify the role of weight suppression.