Incidence of self-harm after bariatric surgery: A nationwide registry-based matched cohort study

Abstract

The aims of this study were to evaluate the longitudinal risk of self-harm and the risk factors for self-harm after bariatric surgery in patients and control subjects without prior self-harm. This observational cohort study was based on prospectively registered data. Patients 18–70 years at time of surgery, body mass index (BMI) > 30 kg/m2, who underwent a primary Roux-en-Y gastric bypass (RYGB) procedure or a primary sleeve gastrectomy between 2007 and 2019 were considered for inclusion. All patients who met the inclusion criteria were matched 1:10 to the general population in Sweden (69 492 patients vs. 694 920 controls). After excluding patients and controls with previous self-harm, a self-harm event occurred in 1408 patients in the surgical group (incidence rate (IR) 3.54/1000 person-years, 95% confidence interval (CI) 3.36–3.73) versus in 3162 patients in the control group (IR 0.81/1000 person-years, 95% CI 0.78–0.84), with a hazard ratio (HR) of 4.38 (95% CI 4.11–4.66, p