Background: The recorded incidence of eating disorders is elevated in people from higher socioeconomic positions, but self-reported eating disorder symptoms are more common in those from lower socioeconomic positions in cross-sectional studies. Longitudinal studies investigating the role of different socioeconomic indicators in the aetiology of a range of eating disorders symptoms might avoid biases associated with the use of clinical samples but have multiple limitations. We aimed to investigate the association between early childhood socioeconomic indicators and eating disorder symptoms across adolescence. Method: We used data from the Avon Longitudinal Study of Parents and Children. Parental income, education, occupation, and financial hardship were reported by mothers between 32 weeks of gestation and 47 months postpartum. Area-level deprivation was derived from the Office of National Statistics indicators linked to the participant's residential post code at 32 weeks gestation. Outcomes were disordered eating (restrictive eating, binge eating, and purging), weight and shape concerns, and body dissatisfaction at age 14, 16, and 18 years. To model these associations, we used univariable and multivariable multilevel logistic and linear regression, and linear regression models. Findings: The sample included 7,824 participants (48.9% females; 3.8% minoritised ethnic background). Greater financial hardship was associated with increased odds of disordered eating (Odds Ratio= 1.06, 95%CI 1.04 to 1.10) and greater weight and shape concerns (Mean difference[MD] = 0.02, 95%CI 0.01 to 0.04) and body dissatisfaction (MD= 0.22 95%CI 0.06 to 0.37). Lower parental education was associated with 1.80 higher odds of disordered eating (95% CI 1.46 to 2.23). Interpretation: Our findings point to potential socioeconomic inequalities in eating disorder identification in clinical settings, which need to be understood and addressed. Reducing population-level socioeconomic inequalities could also aid eating disorder prevention.

The authors have declared no competing interest.

JSH is supported by a Mental Health Research UK PhD Scholarship. FS has been supported by a Wellcome Trust Sir Henry Wellcome Fellowship and a Wellcome Trust Career Development Award for the duration of this study.

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