Clinical Phenotypes and Neurobiology of Youth With Avoidant/Restrictive Food Intake Disorder (ARFID) Across Sex

Avoidant/restrictive food intake disorder (ARFID) is an eating disorder characterized by persistent avoidant/restrictive eating unrelated to body image. Sex differences in clinical phenotypes and neurobiology of ARFID are understudied. We hypothesized that females with ARFID would have a greater frequency of the lack of interest and fear of aversive consequences phenotypes, higher levels of anorexigenic hormones, and greater fMRI activation in brain regions associated with cognitive control during a food cue paradigm. We further hypothesized that males with ARFID would have a greater frequency of the sensory sensitivity profile, higher levels of orexigenic hormones, and greater fMRI activation in reward processing brain regions.

We recruited 96 children and adolescents with ARFID and sub-threshold ARFID (49% female) from two studies on the neurobiology of ARFID and low weight eating disorders from 2016 to 2022. We analyzed ARFID clinical phenotypes; appetite-regulating hormones, ghrelin, cholecystokinin (CCK), peptide YY (PYY), and oxytocin; and fMRI activation of cognitive control and reward-related brain regions during a food cue paradigm using frequentist and Bayesian statistical analysis.

Contrary to our hypothesis, there were no sex differences in frequency of ARFID clinical phenotypes, appetite-regulating hormone levels, or brain activation.

This is the first study to provide empirical evidence that ARFID has a similar clinical and neurobiological presentation in males and females.