Bariatric surgery versus intensive medical therapy in obese patients with diabetes.

BACKGROUND: Observational studies have shown improvement in patients with type 2 diabetes mellitus after bariatric surgery. METHODS: In this randomized, nonblinded, single-center trial, we evaluated the efficacy of intensive medical therapy alone versus medical therapy plus Roux-en-Y gastric bypass or sleeve gastrectomy in 150 obese patients with uncontrolled type 2 diabetes. The mean (±SD) age of the patients was 49±8 years, and 66% were women. The average glycated hemoglobin level was 9.2±1.5%. The primary end point was the proportion of patients with a glycated hemoglobin level of 6.0% or less 12 months after treatment. RESULTS: Of the 150 patients, 93% completed 12 months of follow-up. The proportion of patients with the primary end point was 12% (5 of 41 patients) in the medical-therapy group versus 42% (21 of 50 patients) in the gastric-bypass group (P=0.002) and 37% (18 of 49 patients) in the sleeve-gastrectomy group (P=0.008). Glycemic control improved in all three groups, with a mean glycated hemoglobin level of 7.5±1.8% in the medical-therapy group, 6.4±0.9% in the gastric-bypass group (P<0.001), and 6.6±1.0% in the sleeve-gastrectomy group (P=0.003). Weight loss was greater in the gastric-bypass group and sleeve-gastrectomy group (-29.4±9.0 kg and -25.1±8.5 kg, respectively) than in the medical-therapy group (-5.4±8.0 kg) (P<0.001 for both comparisons). The use of drugs to lower glucose, lipid, and blood-pressure levels decreased significantly after both surgical procedures but increased in patients receiving medical therapy only. The index for homeostasis model assessment of insulin resistance (HOMA-IR) improved significantly after bariatric surgery. Four patients underwent reoperation. There were no deaths or life-threatening complications. CONCLUSIONS: In obese patients with uncontrolled type 2 diabetes, 12 months of medical therapy plus bariatric surgery achieved glycemic control in significantly more patients than medical therapy alone. Further study will be necessary to assess the durability of these results. (Funded by Ethicon Endo-Surgery and others; ClinicalTrials.gov number, NCT00432809.).

Adults with long-duration type 2 diabetes have blunted glycemic and ß-cell function improvements after bariatric surgery.

OBJECTIVE: This study investigated the effect of type 2 diabetes duration on glucose regulation 24 months post-bariatric surgery. METHODS: Twenty-seven adults with short- (<5 years) and long-duration (≥10 years) type 2 diabetes received a mixed-meal tolerance test at baseline and 24 months postsurgery. Body weight, insulin sensitivity, first- and second-phase meal-stimulated insulin secretion, disposition index (i.e., DI or pancreatic ß-cell function), and incretin responses were examined. RESULTS: Adults with short-duration type 2 diabetes had better HbA(1c), greater insulin secretory capacity, and greater DI compared with adults with long-duration type 2 diabetes, despite similar weight loss and incretin responses. Diabetes duration correlated with smaller improvements in HbA(1c) and DI but not weight loss. CONCLUSIONS: Enhanced ß-cell function characterizes the effect of bariatric surgery in adults with diabetes for <5 years, independent of weight loss or incretins. Additional therapy postsurgery may be required to improve glycemia for people with long-standing type 2 diabetes.

Two-year outcomes on bone density and fracture incidence in patients with T2DM randomized to bariatric surgery versus intensive medical therapy.

OBJECTIVE: To determine the 2-year outcomes of Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) vs. intensive medical therapy (IMT) on lean body mass, total bone mass, and bone mineral density (BMD) measures from the STAMPEDE trial. METHODS: 54 subjects (BMI: 36 ± 1 kg/m(2) , age: 48 ± 4 years) with type 2 diabetes (T2DM) (HbA1c : 9.7 ± 2%) were randomized to IMT, RYGB, or SG and underwent DXA at baseline and at 1 and 2 years. RESULTS: At 2 years, the reduction in BMI was similar after RYGB and SG and was greater than IMT (P < 0.001). Lean mass was reduced by ∼10%, total bone mineral content reduced by ∼8%, and hip BMD reduced by ∼9% in both surgical groups and was significantly greater than IMT despite increases in vitamin D intake in all groups. The change in hip BMD correlated with weight loss (r = 0.84, P < 0.0001) and changes in lean mass (r = 0.74, P < 0.0001) and leptin (r = 0.53, P < 0.0001). Peripheral fractures were self-reported in RYGB (4/18 patients), SG (2/19 patients), and IMT (4/16 patients). CONCLUSIONS: Surgically induced weight loss is associated with modest reductions in lean mass, bone mineral content, and BMD, despite calcium and vitamin D supplementation in patients with T2DM. Awareness for bone loss is indicated for patients undergoing bariatric procedures.

Metabolic effects of bariatric surgery in patients with moderate obesity and type 2 diabetes: analysis of a randomized control trial comparing surgery with intensive medical treatment.

OBJECTIVE: To evaluate the effects of two bariatric procedures versus intensive medical therapy (IMT) on ß-cell function and body composition. RESEARCH DESIGN AND METHODS: This was a prospective, randomized, controlled trial of 60 subjects with uncontrolled type 2 diabetes (HbA1c 9.7 ± 1%) and moderate obesity (BMI 36 ± 2 kg/m(2)) randomized to IMT alone, IMT plus Roux-en-Y gastric bypass, or IMT plus sleeve gastrectomy. Assessment of ß-cell function (mixed-meal tolerance testing) and body composition was performed at baseline and 12 and 24 months. RESULTS: Glycemic control improved in all three groups at 24 months (N = 54), with a mean HbA1c of 6.7 ± 1.2% for gastric bypass, 7.1 ± 0.8% for sleeve gastrectomy, and 8.4 ± 2.3% for IMT (P < 0.05 for each surgical group versus IMT). Reduction in body fat was similar for both surgery groups, with greater absolute reduction in truncal fat in gastric bypass versus sleeve gastrectomy (-16 vs. -10%; P = 0.04). Insulin sensitivity increased significantly from baseline in gastric bypass (2.7-fold; P = 0.004) and did not change in sleeve gastrectomy or IMT. ß-Cell function (oral disposition index) increased 5.8-fold in gastric bypass from baseline, was markedly greater than IMT (P = 0.001), and was not different between sleeve gastrectomy versus IMT (P = 0.30). At 24 months, ß-cell function inversely correlated with truncal fat and prandial free fatty acid levels. CONCLUSIONS: Bariatric surgery provides durable glycemic control compared with intensive medical therapy at 2 years. Despite similar weight loss as sleeve gastrectomy, gastric bypass uniquely restores pancreatic ß-cell function and reduces truncal fat, thus reversing the core defects in diabetes.