Background: The aim of this study was to evaluate the long-term effects of laparoscopic sleeve gastrectomy (LSG) on type 2 diabetes mellitus (T2DM) and other related co-morbidities in severely obese patients. Methods: From May 2003 to July 2008, 33 morbidly obese diabetic patients (20 with body mass index [BMI] >50 kg/m(2)) underwent LSG. A total of 23 females and 10 males participated, with a mean age of 49.3 +/- 8 years, mean preoperative BMI of 52.1 +/- 8.5 kg/m(2), mean fasting plasma glucose (FPG) of 143.2 +/- 47.9 mg/dL, mean glycosylated hemoglobin (HbA(1c)) of 7.3% +/- 1.4%, and a mean T2DM duration of 7 years. All patients had a 36-month follow-up, and 13 had a 60-month follow-up. Results: Twenty-nine patients (87.8%) discontinued antidiabetic medications 3 months after LSG, (mean BMI of 42.8 +/- 7.8 kg/m(2); FPG of 104.5 +/- 22.1 mg/dL; HbA(1c) of 5.3% +/- .4%). At 36 months, 22 of 26 LSG patients (84.6%) had normal FPG and HbA(1c) values without antidiabetic therapy. At the 60-month follow-up, 10 of 13 patients (76.9%) had normal FPG and HbA(1c) values without antidiabetic therapy. The Framingham risk score decreased significantly from 9.7% pre-operatively to 4.7% postoperatively. No new diabetic retinopathy occurred during the whole period of observation. Conclusions: This study confirms the efficacy of LSG in the treatment of T2DM and indicates that, at both 36- and 60-month follow-ups, LSG can provide a significant percentage of treated patients with a prolonged remission of T2DM, with diminished cardiac risk factors and no development of diabetic retinopathy. These results compare favorably with those reported after standard medical therapy. (Surg Obes Relat Dis 2013;9:498-502.) (C) 2013 American Society for Metabolic and Bariatric Surgery. All rights reserved.