Effects of gastric bypass surgery in patients with type 2 diabetes and only mild obesity

Cohen RV, Pinheiro JC, Schiavon CA, Salles JE, Wajchenberg BL, Cummings DE. Effects of gastric bypass surgery in patients with type 2 diabetes and only mild obesity. Diabetes Care. 2012;35:1420-1428.  

The prevalence of obesity/overweight in the United States continues to grow; the latest National Health and Nutrition Examination Survey estimations indicate a combined overweight and obesity prevalence of 68.8% for US men and women aged 20 years with BMI ≥25 kg/m2, with decreased prevalence seen among those with higher BMI (BMI ≥30-40 kg/m2).1 

Bariatric surgery may be indicated for those with BMI 40 kg/m2 (or BMI ≥35-40 kg/m2 in those with associated comorbidities);2 this indication excludes those in lower BMI categories, in whom the prevalence of obesity/overweight is most prevalent. The authors of the current prospective study sought to examine the potential benefits of laparoscopic Roux-en-Y gastric bypass (LRYGB) among those with BMI 30-34.9 kg/m2 (class I obesity) and type 2 diabetes.*    

For up to 6 years of follow-up (median follow-up: 5 years), the following main outcome measures were assessed among study subjects who elected to undergo LRYGB (N=66):  

  • % of subjects with diabetes remission (defined as A1C <6.5% without diabetes medication)  
  • Operative safety  

Additional outcomes included changes in lipid profiles, BP, waist circumference, body weight, and estimated 10-year CV risk.  

Subject profile:  

  • Majority male (n=40; n=26 females)  
  • Mean age: 47 years  
  • All white  
  • Longstanding diabetes per ADA criteria (mean 12.5 years)  
  • Poor glycemic control (mean A1C: 9.7%)  
  • Mean waist circumference: 113 cm males; 101 cm females  
  • Hypercholesterolemia: 50%  
  • Hypertension: 39%  
  • Hypertriglyceridemia: 47% 

Results over median follow-up of 5 years:  

Operative safety  

  • 15% rate of minor complications (adverse outcomes deemed related to surgery but not requiring readmission to hospital or continued intensive treatment [eg, nausea, port-site hematomas, etc])  
  • No major surgical complications (eg, deep vein thrombosis, venous thromboembolism, tracheal reintubation, endoscopy, tracheostomy, percutaneous drain placement, abdominal reoperation, or failure to be discharged within 30 days)  
  • Mean hospital stay: 1.5-4.0 days  
  • No mortality 

Glycemic control  

  • Decreases seen in  
    • A1C (9.7 ± 1.5% to 5.9 ± 0.1%; P<0.001)  
    • FPG (156 ± 11 mg/dL to 97 ± 5 mg/dL; P<0.001)  
    • Insulin resistance (9.2 ± 2.3 to 2.3 ± 0.8); showed a marked decrease within first 6 months then decreased slowly thereafter  
     
  • 88% of subjects achieved diabetes remission (A1C <6.5% without medication)  
    • No recurrence of diabetes following remission seen over follow-up period  
     
  • 11% of subjects had improvement in diabetes without full remission (A1C <7.0%)

Waist circumference and total body weight  

  • Improvements seen for both measures (P<0.001 for both)  
    • At 5 and 6 years, significant correlations were seen between weight loss and FPG decrease; no significant correlations seen between weight loss and FPG decrease at any time point before 5 years.   
    • No significant correlations were seen between weight loss and decrease in A1C at any time point  
     

Additional parameters  

  • Resolution seen in  
    • Hypertension: 58% of participants  
    • Hypercholesterolemia: 64% of participants§  
    • Hypertriglyceridemia: 58% of participants§  
     
  • Improvements seen in  
    • Mean BP (P<0.05 for diastolic and systolic)  
    • Total cholesterol (P<0.001)  
    • LDL-C (P<0.001)  
    • Triglycerides (P=0.003)  
    • HDL-C (P=0.002)  
     

*These patients do not meet the existing criteria for bariatric surgery per the 1991 NIH consensus statement on gastrointestinal surgery for severe obesity2  

†Per definitions in The Endocrine Society guidelines (Rosenzweig JL, et al. J Clin Endocrinol Metab. 2008;93[10]:3671-3689.): hypertension: BP >130/80 mm Hg; hypercholesterolemia: LDL-C >130 mg/dL (among those with resolved diabetes) or >100 mg/dL (among those with persistent diabetes) without lipid-lowering medication; hypertriglyceridemia: triglycerides >150 mg/dL.  

Considered resolved if subject had BP <130/80 mm Hg without BP-lowering medication  

§Considered resolved if subject had triglycerides <150 mg/dL; LDL-C <130 mg/dL (among those with resolved diabetes) or <100 mg/dL (among those with persistent diabetes) without lipid-lowering medication

1. Flegal KM, Carroll MD, Kit BK, Ogden CL. Prevalence of obesity and trends in the distribution of body mass index among US adults, 1999-2010. JAMA. 2012;307(5):491-497.  

2. NIH conference. Gastrointestinal surgery for severe obesity. Consensus Development Conference Panel. Ann Intern Med. 1991;115(12):956-961.  

 

September 2012  

This overview was created by KnowledgePoint360 Group, LLC, and was not associated with funding via an educational grant or a promotional/commercial interest.  

Related content 

Read more about this study and additional cutting-edge diabetes data in the September 2012 issue of Clinical Insights® in Diabetes. Click here. 

Roux-en-Y Gastric Bypass Surgery in Type 2 Diabetes and Mild Obesity: Design 

Roux-en-Y Gastric Bypass Surgery in Type 2 Diabetes and Mild Obesity: Glycemic Control Results 

Roux-en-Y Gastric Bypass Surgery in Type 2 Diabetes and Mild Obesity: Operative Safety, Waist Circumference 

Roux-en-Y Gastric Bypass Surgery in Type 2 Diabetes and Mild Obesity: Additional Parameters 

Last Modified: 11/15/2013