Lifetime Self-Harm Behaviors Are Not More Prevalent in Bariatric Surgery Candidates than in Community Controls with Obesity

Objective: The study aimed at investigating the lifetime prevalence of 22 self-harm behaviors in bariatric surgery candidates (pre-bariatric surgery group; PSG) compared to community controls with obesity (obese community group; OCG). Methods: The Self-Harm Inventory (SHI) was administered to the PSG (n = 139, BMI ≥ 35 kg/m²) and to the OCG (n = 122, BMI ≥ 35 kg/m²). Results: Group comparison of cumulative SHI scores indicated a trend towards less endorsed SHI items in the PSG compared to the OCG (median_PSG = 1.00, IQR_PSG = 2.00, median_OCG = 1.00, IQR_OCG = 2.25, U = 7.241, p = 0.033, η² = 0.02). No significant group differences were found with regard to the rate of suicide attempts (12.4% vs. 9.4% for OCG vs. PSG). At least one type of lifetime self-harm behavior was admitted by 51.8% of the PSG and 63.9% of the OCG (χ²₍₁₎ = 3.91, p = 0.048). The results of logistic regressions using Firth's bias reduction method with at least one SHI item endorsed as dependent variable, group as categorical predictor (PSG as baseline), and age or BMI or PHQ-4 as continuous control variable indicated that only PHQ-4 had a positive effect on the odds ratio. Conclusion: The results suggest that self-harm (including suicidal attempts) is not more prevalent in bariatric surgery candidates than in community control participants with obesity. Further studies are needed to investigate self-harm in bariatric surgery patients, prior and following surgery, compared to non-operated patients with obesity.