Research Of Bariatric Surgery On The Function Of The Endocrine Axis In Obese Patients

Objective: Bariatric surgery is currently an effective treatment for obesity with Type 2 diabetes(T2D),which mainly includes Roux-en-Y gastric bypass(RYGB)and Sleeve Gastrectomy(SG).The purpose of this study was to investigate the changes of endocrine axis in obese Chinese patients with T2 D after RYGB,and explore its influencing factors.Methods: Two data sets were included in this study.One was 45 obese male patients with T2 D who underwent RYGB in our hospital from February 2015 to December 2016.The other was 81 obese patients with T2 D who received RYGB from February 2012 to August 2015 in our hospital.Clinical data and serum samples were collected.The changes of sex hormones and thyroid hormones after operation were analyzed and the related factors affecting the changes were discussed.Results: 1.After surgery,both the levels of total testosterone(TT)and sex hormone-binding globulin(SHBG)increased,while the levels of estradiol(E2)decreased.However,the calculated free testosterone(cFT),follicle-stimulating hormone(FSH),and luteinizing hormone(LH)levels remained unchanged.Multiple linear regression analysis showed that the visceral fat area(VFA)was the only significant and independent parameter associated with TT levels at baseline.After surgery,decreases in the VFA continued to be associated with increases in TT.2.Both Free ThyroxineIndex(FT4)levels and Thyroid Stimulating Hormone(TSH)levels decreased significantly 6 months postsurgery.Multiple linear regressionanalysis showed that the waist/hip ratio(WHR)and duration of diabetes were independent factors contributing to this decrease in FT4 levels.Moreover,changes in TSH levels were significantly and positively correlated with 2-hour postprandial blood glucose(2hPG)at baseline.Conclusion: 1.RYGB may help to improve hypogonadism by reducing adipose tissue,especially visceral fat,to elevate testosterone levels in obese men with T2 D.2.The decrease of FT4 and TSH indicates that the decrease of body weight and the remission of T2 D were accompanied by the compensatory reductions of energy expenditure.