Plasma concentrations of SSRI/SNRI after bariatric surgery and the effects on depressive symptoms

Patrick Pasi; Dino Kröll; Alena Siegfried; Martin Sykora; Alessandro Wildisen; Cristiana Milone; Gabriella Milos; Laura Horka; Stefan Fischli; Christoph Henzen

doi:10.3389/fpsyt.2023.1132112

Plasma concentrations of SSRI/SNRI after bariatric surgery and the effects on depressive symptoms

Front Psychiatry. 2023 Apr 25:14:1132112. doi: 10.3389/fpsyt.2023.1132112. eCollection 2023.

Authors

Affiliations

¹ Department of Consultation-Liaison Psychiatry and Psychosomatic Medicine, University Hospital Zürich, University of Zürich, Zürich, Switzerland.
² Division of Visceral Surgery, University Hospital Bern, University of Bern, Bern, Switzerland.
³ Department of Surgery, Division of Visceral Surgery, Cantonal Hospital, Lucerne, Switzerland.
⁴ Department of Internal Medicine, Division of Endocrinology, Cantonal Hospital, Lucerne, Switzerland.

Abstract

Background: Depression and treatment with antidepressants SSRI/SNRI are common in people with morbid obesity who are candidates for bariatric surgery. There is few and inconsistent data about the postoperative plasma concentrations of SSRI/SNRI. The aims of our study were to provide comprehensive data about the postoperative bioavailability of SSRI/SNRI, and the clinical effects on depressive symptoms.

Methods: Prospective multicenter study including 63 patients with morbid obesity and therapy with fixed doses of SSRI/SNRI: participants filled the Beck Depression Inventory (BDI) questionnaire, and plasma levels of SSRI/SNRI were measured by HPLC, preoperatively (T0), and 4 weeks (T1) and 6 months (T2) postoperatively.

Results: The plasma concentrations of SSRI/SNRI dropped significantly in the bariatric surgery group from T0 to T2 by 24.7% (95% confidence interval [CI], -36.8 to -16.6, p = 0.0027): from T0 to T1 by 10.5% (95% 17 CI, -22.7 to -2.3; p = 0.016), and from T1 to T2 by 12.8% (95% CI, -29.3 to 3.5, p = 0.123), respectively.There was no significant change in the BDI score during follow-up (-2.9, 95% CI, -7.4 to 1.0; p = 0.13).The clinical outcome with respect to SSRI/SNRI plasma concentrations, weight change, and change of BDI score were similar in the subgroups undergoing gastric bypass surgery and sleeve gastrectomy, respectively. In the conservative group the plasma concentrations of SSRI/SNRI remained unchanged throughout the 6 months follow-up (-14.7, 95% CI, -32.6 to 1.7; p = 0.076).

Conclusion: In patients undergoing bariatric surgery plasma concentrations of SSRI/SNRI decrease significantly by about 25% mainly during the first 4 weeks postoperatively with wide individual variation, but without correlation to the severity of depression or weight loss.

Keywords: Beck depression inventory (BDI); body mass index (BMI); laparoscopic Roux-en-Y gastric bypass (RYGB); selective serotonin reuptake inhibitor (SSRI); serotonin noradrenalin reuptake inhibitor (SNRI); sleeve gastrectomy (SG).