Background Psychiatric conditions, eating disorders (EDs), and exposure to violence are highly prevalent in patients with severe obesity. However, their association with postoperative weight trajectories following bariatric surgery remains unclear.

Objective To assess the associations between eating disorders, psychiatric conditions, and history of violence with multiple dimensions of weight trajectory after bariatric surgery.

Methods This retrospective study included 414 patients with severe obesity from the OBESEPI cohort who underwent bariatric surgery at Nancy University Hospital (France). Psychological factors were assessed using a standardized preoperative psychiatric interview. Weight outcomes included preoperative BMI change, maximal BMI loss (ΔBMImax), final BMI change (dBMIdf), weight regain (BMIR), and magnitude of weight regain (dBMIR). Multivariable linear and logistic regression models were adjusted for age and sex.

Results Psychological factors were not associated with baseline BMI or preoperative BMI variation. A history of violence was significantly associated with greater maximal BMI loss (β = 1.99, 95% CI [0.73–3.26]; p = 0.002) and greater final BMI reduction (β = 1.81, 95% CI [0.47– 3.14]; p = 0.009). Eating disorders and psychiatric conditions were not associated with weight loss outcomes. No association was observed between overall exposure to violence and weight regain. However, subtype analyses showed that physical violence was associated with a higher risk of weight regain, whereas psychological violence was associated with a lower risk. No significant associations were found for the magnitude of weight regain.

Conclusions Eating disorders and psychiatric conditions were not associated with postoperative weight outcomes in this cohort. In contrast, exposure to violence—particularly when differentiated by subtype—was associated with distinct patterns of weight loss and regain. These findings highlight the relevance of trauma-informed assessment in bariatric care and support a more individualized approach to obesity management.

The authors have declared no competing interest.

This study did not receive any funding

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The OBESEPI study is registered at ClinicalTrials.gov (identifier: NCT02663388). The study protocol was approved by the Ethics Committee of Nancy University Hospital (CPP Est III, number: 2015-A01175-44).

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The data that support the findings of this study are available from the corresponding author upon reasonable request