Obese patients with higher TSH levels had an obvious metabolic improvement after bariatric surgery

Objective: Bariatric surgery has become the most effective treatment for mo rbid obesity. Increasing evidence showed that bariatric surgery can alleviate insulin resistance and influence thyroid function. This study aimed to investigate the relationship between changes in thyroid function and adipose tissue insulin resistance (adipo-IR) after bariatric surgery. Methods: A total of 287 non-diabetic participants with regular thyroid function were recruited and divided into the lean, overweight and obese group s. Among them, 50 morbidly obese patients submitted to bariatric surgery. Results: The obese group had a higher level of adipo-IR, thyroid-stimul ating hormone (TSH), free triiodothyronine (FT3), FT3/free thyroxine (FT4) an d metabolism disorders than the lean and overweight groups. BMI was correlated with TS H, FT3, FT3/FT4 and adipo-IR (r = 0.309, 0.315, 0.322 and 0.651, respectively, all P < 0.001). Adipo-IR was significantly correlated with TSH (r = 0.402, P < 0.001), FT3 (r = 0.309, P < 0.001), and FT3/FT4 (r = 0.228, P < 0.05). Bariatric surgery resulted in a sharp decline in BMI, adipo-IR, TSH, FT3 and FT3/FT4 levels, meanwhile, metabolic disorders imp roved. The decrease in BMI after bariatric surgery was significantly correlated with reductions in adipo-IR (r = 0.577, P < 0.001) and TSH (r = 0.401, P = 0.005). Interestingly, the fasting blood glucose, fasting insulin, adipo-IR and TSH in the higher TSH gr oup decreased more remarkably than in the lower TSH group. Conclusion: Obese individuals with higher TSH levels had an obvious metabo lic improvement after bariatric surgery