Thyroid Function Improved after Laparoscopic Sleeve Gastrectomy in Severe Obesity and Related to Inflammatory Changes

Abstract

Objective: Obesity, a state of chronic low grade inflammation, has been reported to be associated with significant alterations of thyroid function. The purpose of this study is to evaluate the effect of laparoscopic sleeve gastrectomy (LSG) on thyroid function and its relation with inflammatory changes in severely obese patients. Methods: We performed a retrospective observational study of 128 severely obese patients (61.7% female; age 31.8 ± 10.0 years, BMI 39.4 ± 5.8 kg/m2) submitted to LSG. Patients were subdivided in two groups: euthyroid group and subclinical hypothyroidism (SCH) group. TSH, FT4, anthropometric data, and inflammatory markers were collected pre- and 1, 3, 6, and 12 months post-LSG. Results: The mean percent weight loss at 12 months was 37.2% ± 11.8%. The mean BMI decreased from 39.4 ± 5.8 kg/m2 to 27.1 ± 3.9 kg/m2. Patients with SCH (37.5% of patients) and higher TSH showed higher BMI, HOMA-IR, interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) than those in euthyroid group (all P < 0.05). After surgery, TSH levels significantly decreased at 1, 3, 6, and 12 months regardless of thyroid function, which presented more apparent in SCH group. Additionally, we observed marked reduction of IL-6, IL-8, TNF-α, and CRP levels in SCH group, as well as IL-8, TNF-α, and CRP in euthyroid group from baseline by 12 months postoperatively. Moreover, decreased TSH levels correlated significantly with decreased BMI, HOMA-IR, IL-6, and TNF-α at 12 months after LSG. Conclusion: SCH in severely obesity subjects appears to be associated with excess weight, insulin resistance, and elevated inflammatory markers. LSG promotes a decrease of TSH that is significantly greater in patients with SCH, and associated with alleviation of inflammatory status in addition to substantial weight loss and improved insulin resistance after surgery. Disclosure C. Zhu: None. F. Mei: None. J. Gao: None. X. Wang: None. L. Li: None. L. Lu: None. D. Zhou: None. S. Qu: None.