Background: The effect of bariatric surgery on thyroid hormone changes yielded inconsistent results. The aim of the present study was to assess the change of thyroid hormone levels following laparoscopic sleeve gastrectomy (LSG), with or without antral preservation (AP).
Methods: Thyroid hormones (TSH, FT3, FT4) were examined preoperatively, at the end of the first postoperative month, and first postoperative year. Secondly, antral resection (AR) and AP were compared at inducing weight loss and thereby affecting thyroid hormone levels.
Results: Euthyroid obese patients (86 female/20 male) underwent LSG. Of these, 58 patients underwent AR and 48 patients AP. The mean FT3 levels significantly decreased both in the first postoperative month and the first year (P < 0.001), whereas mean TSH levels decreased significantly in the first postoperative year (P < 0.001). FT4 levels remained nearly unchanged (P = 0.517). Postoperative first year body mass index (BMI) loss, excess BMI loss percentile (%EBMIL), and total body weight loss percentile (%TWL) were significantly higher in AR group than the AP group (P ≤ 0.01). When the change in thyroid hormone levels was analyzed by pyloric distance according to time periods, no significant difference was found in TSH and FT4 levels (P > 0.05); however, reduction in FT3 levels was significantly greater in patients with AR than in AP patients (P = 0.028).
Conclusion: LSG promotes significant reduction in TSH and FT3 levels, whereas FT4 levels remain unchanged. LSG with AR provides more weight loss in short term and appears to be more effective at lowering FT3 levels.
Keywords: Antral preservation; Free thyroxine; Laparoscopic sleeve gastrectomy; Thyroid-stimulating hormone-free triiodothyronine.