Abstract
INTRODUCTION: Laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic sleeve gastrectomy (LSG) are common bariatric procedures that are effective in treating type 2 diabetes (T2D) in patients with obesity. Limited data from randomized trials are available comparing longevity of diabetes remission directly between the two procedures beyond 5 years. METHODS: A prospective, randomized, parallel, two-arm, clinical trial comparing the outcomes of silastic ring (SR)-LRYGB versus LSG was conducted at a single (Auckland, New Zealand) center. Patients and researchers were blinded until the 5-year mark and follow-up after this was unblinded. Eligible patients had T2D of > 6 months duration with a BMI 35--65 kg/m(2) and were aged 20-55 years. Randomization was 1:1 to SR-LRYGB and LSG following induction of anesthesia and was stratified by age group, BMI group, ethnicity, diabetes duration, and insulin therapy. The primary outcome was T2D remission, defined as HbA1c < 6% (42 mmol/mol), without the use of glucose-lowering medications. RESULTS: A total of 114 patients were randomized of whom 6 died before the 7-year follow-up (2 SR-LRYGB, 4 LSG). Diabetes remission, assessed in 89 (82.4%) of the remaining patients, was seen in 23/50 (46.0%) after SR-LRYGB and 12/39 (30.8%) after LSG (adjusted OR 4.64, 95% CI 1.39, 15.52, p = 0.013). Percentage total body weight loss was greater after SR-LRYGB than LSG (26.2% vs 13.4%; absolute difference 12.8%; 95% CI 7.2%, 18.2%; p < 0.001). Complication rates were similar between groups. CONCLUSION: SR-LRYGB was superior to LSG for diabetes remission and weight loss at 7 years following surgery, with acceptable complication rates.