The effects of laparoscopic sleeve gastrectomy vs. gastric bypass in circulating adiponectin, testosterone and their associations with carotid intima-media thickness in men.

Background : Obesity increases cardiovascular risk in men through several pathophysiological mechanisms. Among them, low adiponectin (APN) and possibly obesity-associated hypogonadism have been described. As obesity surgery is a proven therapy to decrease cardiovascular risk, we aimed to study the association of the latter with changes in circulating adiponectin by comparing laparoscopic Roux-en-Y gastric bypass (RYGB) with sleeve gastrectomy (SG). Methods: We included 60 men, 20 submitted to RYGB, 20 to SG, and 20 to life-style modification (controls). Serum APN, total testosterone (TT), and sex hormone binding globulin (SHBG) were measured at baseline and six months after surgery. Free testosterone (FT) was calculated, and carotid intima-media thickness (cIMT) measured by ultrasonography. Results: Circulating APN increased after both surgical techniques, whereas no changes were observed in controls (P<0.001 for the interaction, P=0.005 for RYGB vs. controls, P=0.001 for SG vs. controls, P=0.695 for RYGB vs. SG). The increase in APN correlated positively with TT (r=0.518, P<0.001) and FT (r=0.320, P=0.013) and inversely with cIMT (r=-0.283, P=0.028). The increase in TT and FT inversely correlated with changes in cIMT (r=-0.428, P=0.010 and r=-0.269, P=0.038). After multivariate linear regression only weight loss was associated with cIMT (R 2 =0.245, P<0.001). Conclusions: Both RYGB and SG induced a similar increase in APN in men which paralleled TT, FT and SHBG. The decrease in cIMT after surgery inversely correlated with APN but was mainly associated with weight loss.