AB107. SOH22ABS162. Antidepressant use among patients presenting for bariatric surgery

Background: Bariatric surgery is effective for sustained weight loss (WL) and improvement in obesity related co-morbidities. Depression is the most common psychiatric illness amongst patients referred for bariatric surgery. Evidence suggests that some commonly prescribed antidepressants may be associated with weight gain. The aim of this study was to examine the type and class of antidepressant medication prescribed pre-operatively among patients undergoing bariatric surgery between 2018–2021 within St. Vincent’s Hospital group and investigate whether antidepressants had an impact on total WL following surgery.

Methods: Patient notes including clinic appointments, admissions, psychology reports and dietician reports were examined retrospectively from surgery to follow up.

Results: A total of 260 patients were eligible. Fifty-nine (22.6%) were taking antidepressant medication pre-operatively. Based on classification; there were 44 patients on SSRIs, 8 on SSNRI, 4 on NaSSA and 3 on Tricyclic Antidepressants (TCAs). Approximately twenty-nine percent of patients were on high-risk agents for weight gain. Thirty percent had a sleeve gastrectomy and 75% had a gastric bypass. There was no significant difference in the median WL at 12 months, 29% (antidepressants) versus 30% (no antidepressants) (P=0.668).

Conclusions: The most recent antidepressant prescribing guidelines in Ireland do not include considerations for potential weight gain. Although no difference in WL was identified within the first 12 months, little is known about longer-term weight outcomes. National guidelines on antidepressants should be updated to include obesity related considerations. However, the use of antidepressants did not appear to affect weight outcomes in our patient cohort and may not impact WL post-operatively.

Keywords: Bariatric surgery; weight loss (WL); antidepressant medication; depression; psychiatric illness