Investigating Orthorexia Nervosa With The ORTO-R in a Sample of University Students With Or Without Subthreshold Autism Spectrum: Focus On Dietary Habits and Sex Differences

Abstract

Purpose: The aim of the present study was to investigate the presence of ON symptoms, measured by means of the ORTO-R, in a sample of University students with or without AT, specifically focusing on evaluating the role of sex and of dietary habits in the association between ON and autism spectrum. Methods: Subjects were requested to anonymously fulfil the ORTO-R and the Adult Autism Subthreshold Autism Spectrum (AdAS Spectrum) through an online form. Results: 2140 students participated in the study. Subjects with significant AT reported significantly higher ORTO-R scores than subjects without AT. Females and subjects following a vegetarian/vegan diet reported significantly higher ORTO-R scores than males and than subjects following an omnivorous diet, respectively. Significant positive correlations were found between ORTO-R and AdAS Spectrum scores. A decision tree model, with sex, type of diet and presence of AT as independent variables and ORTO-R score as dependent variable, showed in the first step the presence of significantly higher ORTO-R scores among females than among males, and in the second step showed in both sexes the presence of higher ORTO-R scores among subjects with AT than in those without. A significant interaction of sex and presence/absence of AT was reported on ORTO-R score, with a higher increasing trend of ORTO-R score with the increase of AdAS Spectrum score among females than among males. Conclusions: Our results further highlighted the association between AT and ON, in particular among females.