Medical comorbidities and endocrine dysfunction in low-weight females with avoidant/restrictive food intake disorder compared to anorexia nervosa and healthy controls

Objective: To improve our understanding of medical complications and endocrine alterations in patients with low-weight avoidant/restrictive food intake disorder (ARFID) and how they may differ from those in anorexia nervosa (AN) and healthy controls (HC). Method: We performed an exploratory cross-sectional study comparing low-weight females with ARFID (n = 20) with females with AN (n = 42) and HC (n = 49) with no history of an eating disorder. Results: We found substantial overlap in medical comorbidities and endocrine features in ARFID and AN, but with earlier onset of aberrant eating behaviors in ARFID. We also observed distinct medical and endocrine alterations in ARFID compared to AN, such as a greater prevalence of asthma, a lower number of menses missed in the preceding 9 months, higher total T3 levels, and lower total T4 : total T3 ratio; these differences persisted after adjusting for age and might reflect differences in pathophysiology, acuity of weight fluctuations, and/or nutritional composition of food consumed. Conclusion: These results highlight the need for prompt diagnosis and intensive therapeutic intervention from disease onset in ARFID.