A specific association between laxative misuse and suicidal behaviours in patients with anorexia nervosa and bulimia nervosa

Objective Eating disorders (ED) are associated with an in increased risk of suicidal behaviours. Laxative abuse might alter the gut-brain axis signaling, that might be implicated in the pathophysiology of suicide. This study aims to determine the association between laxative misuse and suicide attempt (SA) and suicidal ideation (SI) in patients with ED. Methods 277 patients with ED were recruited from an Eating Disorder Unit of Lapeyronie Academic Hospital, Montpellier, France. Sociodemographic and clinical data were collected. Chi-square and t test were used, with Bonferroni corrections where required. Multiple regression models assessed the relationships between laxative misuse, SA, and SI. Results 62 (22.4%) patients reported lifetime laxative misuse. They were more likely to have a history of SA than non-misusers [43.83 vs 19.9%, p < 0.001, odds ratio (OR) 3.68]. In the multivariate model, adjusted for other confounders, lifetime laxative misuse remained associated with SA (adjusted OR 3.79, p = 0.041). In past 28 days, patients with SA history reported misusing laxatives for more days than patients without SA history (6 vs 1.5 days, p = 0.01, adjusted for vomiting and ED severity). Laxative use days during past 28 days was associated with current SI, adjusted for vomiting in the same period (p = 0.017). Conclusions Current and lifetime laxative misuse were associated with SA history and current SI in patients with ED, at least in part independently of other suicide-related factors.