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Nonfatal self-injury in the first year after surgery: a population-based epidemiologic study
Calvin Diep1, Julian F Daza2, Sandra Lee3
1Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto, ON, Canada; Institute of Health Policy, Management and Evaluation, Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada.
Background:
Recovery after surgery can be psychologically distressing, putting patients at risk of suicidal behaviours such as nonfatal self-injury (NFSI). We evaluated the incidence and identified factors associated with NFSI after surgery.
Methods:
Linked administrative databases from New York state were used to identify adults (≥18 yr) undergoing a broad range of surgical procedures between 2016 and 2018. The primary outcome was presentation to an emergency department or hospitalisation for NFSI within 365 days of discharge from the index surgical admission. The incidence was compared with two comparator groups using doubly robust estimation: percutaneous coronary interventions and cataract procedures. Patient- and surgery-related factors associated with NFSI after surgery were determined using Cox models.
Results:
Among 1 165 881 patients, 824 presented with NFSI within the year after surgery (incidence 7.07 per 10 000 patients). This was higher than the incidence in the percutaneous coronary interventions group (4.88 per 10 000; adjusted hazard ratio, 1.55; 95% confidence interval, 1.06-2.27) and the cataract group (1.52 per 10 000; adjusted hazard ratio, 1.48; 95% confidence interval, 1.04-2.09). Risk factors for NFSI were younger age, White race, lower income, rural residence, previous psychiatric history, and nonelective surgery.
Conclusions:
Select patient groups were more susceptible to NFSI after surgery. The true burden of suicidal behaviours and severe psychological distress after surgery is likely underestimated by analyses of administrative data. Future studies should investigate psychological distress after surgery using validated instruments.
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