ORIGINAL CONTRIBUTIONS Comparison of the Effect of Gastric Bypass and Sleeve Gastrectomy on Metabolic Syndrome and its Components in a Cohort: Tehran Obesity Treatment Study (TOTS) Maryam Barzin 1 & Mohammad Ali Kalantar Motamedi 1 & Sara Serahati 1 & Alireza Khalaj 2 & Peyman Arian 2 & Majid Valizadeh 1 & Davood Khalili 3 & Fereidoun Azizi 4 & Farhad Hosseinpanah 1,5 # Springer Science+Business Media New York 2017 Abstract Introduction Metabolic syndrome (MetS) is a prevalent coun- terpart of morbid obesity. With the surgical technique of sleeve gastrectomy (SG) gaining widespread acceptance for weight loss in morbid obese patients, we aimed to undertake a study to compare its effectiveness to gastric bypass (GB) for metabolic control in these patients. Methods A total of 425 patients from a prospectively collect- ed database of morbid obese subjects between 18 and 65 years of age undergoing a primary bariatric procedure from March 2013 to September 2015 were included. Statistical analysis was performed using general estimation equation and propensity scores, and odds ratios were calculated. Results Three hundred nineteen patients underwent SG and 106 underwent GB. Mean age of the patients was 37.8 ± 11.7, and mean body mass index (BMI) was 44.3 ± 5.9 kg/m 2 . MetS was present in 61.4% of patients and diabetes mellitus in 48.6%. MetS prevalence decreased from 60 and 64% in the SG and GB groups to 16 and 10% at 12 months, respectively. These improvements were consistent throughout the study period in both groups, with no significant difference between the two groups (for all variables: P trend < .001, P interaction > .05). After propensity score-adjusted analysis, nei- ther surgical technique showed superiority over the other re- garding metabolic improvement (OR for MetS resolution: 0.81, 95% CI: 0.49–1.34). Conclusions In this short-term study with 1-year follow-up, SG showed similar results to GB in terms of weight loss, MetS resolution, and glycemic control in a large Middle Eastern cohort. Long-term studies are needed to further investigate the effectiveness of SG in this regard. Keywords Sleeve gastrectomy . Gastric bypass . Bariatric surgery . Morbid obesity . Metabolic syndrome Introduction Metabolic syndrome (MetS) is a constellation of metabolic abnormalities closely linked to obesity and insulin resistance. It is associated with an increased risk of many diseases, in- cluding cardiovascular disease (CVD), stroke, type 2 diabetes mellitus (T2DM), liver problems, and all-cause mortality. It is a common feature in morbidly obese patients and entails in- creased health risks in this population, as well as increasing burden of healthcare costs [1, 2]. Evidence suggests weight loss can effectively improve MetS and its components, and bariatric surgery has proved to be a promising treatment option, if not the best, to achieve this goal [3]. Bariatric surgery induces not only significant * Farhad Hosseinpanah fhospanah@endocrine.ac.ir 1 Obesity Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran 2 Faculty of Medicine, Shahed University, Tehran, Iran 3 Prevention of Metabolic Disorders Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran 4 Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran 5 Department of Internal Medicine, School of medicine, Shahid Beheshti Medical University (M.C.) Obesity Research Center, Tehran, Iran OBES SURG DOI 10.1007/s11695-016-2526-0