Self-harm Emergencies After Bariatric Surgery A Population-Based Cohort Study

IMPORTANCE Self-harm behaviors, including suicidal ideation and past suicide attempts, are frequent in bariatric surgery candidates. It is unclear, however, whether these behaviors are mitigated or aggravated by surgery. OBJECTIVE To compare the risk of self-harm behaviors before and after bariatric surgery. DESIGN, SETTING, AND PARTICIPANTS In this population-based, self-matched, longitudinal cohort analysis, we studied 8815 adults from Ontario, Canada, who underwent bariatric surgery between April 1, 2006, and March 31, 2011. Follow-up for each patient was 3 years prior to surgery and 3 years after surgery. MAIN OUTCOMES AND MEASURES Self-harm emergencies 3 years before and after surgery. RESULTS The cohort included 8815 patients of whom 7176 (81.4%) were women, 7063 (80.1%) were 35 years or older, and 8681 (98.5%) were treated with gastric bypass. A total of 111 patients had 158 self-harm emergencies during follow-up. Overall, self-harm emergencies significantly increased after surgery (3.63 per 1000 patient-years) compared with before surgery (2.33 per 1000 patient-years), equaling a rate ratio (RR) of 1.54 (95% CI, 1.03-2.30; P = .007). Self-harm emergencies after surgery were higher than before surgery among patients older than 35 years (RR, 1.76; 95% CI, 1.05-2.94; P = .03), those with a low-income status (RR, 2.09; 95% CI, 1.20-3.65; P = .01), and those living in rural areas (RR, 6.49; 95% CI, 1.42-29.63; P = .02). The most common self-harm mechanism was an intentional overdose (115 [72.8%]). A total of 147 events (93.0%) occurred in patients diagnosed as having a mental health disorder during the 5 years before the surgery. CONCLUSIONS AND RELEVANCE In this study, the risk of self-harm emergencies increased after bariatric surgery, underscoring the need for screening for suicide risk during follow-up.