Diabesity : A Literature Review

1. Diabesity: A Literature Review By: Courtney Saia

2. Purpose Statement: • To determine whether Bariatric surgery is effective at eradicating Type 2 Diabetes Mellitus (T2DM).

3. Diabetes: • T2DM affects more than 170 million people worldwide. • Limited success has been reached in the treatment of diabetes. • Estimated that the number of individuals living with diabetes will increase to 365 million worldwide by 2030. • People with Diabetes are more likely to have: cardiovascular, renal and ophthalmic comorbidities.

4. Obesity: • World Health Organization (WHO) estimates more than 1.6 billion people are overweight, 400 million are obese. • More than 77 million American adults are obese. • The literature suggests diet and exercise combined along with weight reduction medications does not result in durable weight loss for obesity.

5. Diabesity: • Due to the substantial link between T2DM and obesity the coining of the word Diabesity has been prompted.

6. Bariatric Surgery: • Typically results in sustained weight loss and durable glycemic control. • A surgery performed on the stomach and/or intestines in an effort to help an individual with obesity lose weight. • Four types of procedures: • Laparoscopic Adjustable Gastric Banding (LAGB) • Biliopancreatic Diversion with Duodenal Switch (BPD-DS) • Sleeve Gastrectomy (SG) • Roux-en-Y Gastric Bypass (RYGB)

7. Bariatric Surgery: Appropriateness Criteria • Age: • Male: ≥ 45 years • Female: ≥ 55 years • BMI: ≥ 35 • Severity of obesity-related comorbidities: • Established coronary heart disease • Other atherosclerotic diseases • T2DM • Sleep apnea • Stroke • Cancer • Osteoarthritis • Gallstones • Stress incontinence • Gynecological abnormalities

8. Laparoscopic Adjustable Gastric Banding (LAGB): • Restrictive Operation • Rigid, plastic band with a saline filled rubber, balloon lining is used. • Band is placed around the upper section of the stomach (below the gastroesophageal junction). • Flexible tubing is connected from the band to a port on the outside of the body. • Port allows for the surgeon to adjust the saline content of the band by a hypodermic needle.

9. Laparoscopic Adjustable Gastric Banding (LAGB):

10. Sleeve Gastrectomy (SG): • Restrictive Operation. • 10-14 mm is placed along the right side of the stomach. • Surgical stapler is fired adjacent to the tube until the left side of the stomach is completely restricted  banana-shaped stomach (holds ≈ 150-200 mL) • Decreases ghrelin levels.

11. Sleeve Gastrectomy (SG):

12. Biliopancreatic Diversion with Duodenal Switch (BPD-DS): • Restrictive and Malabsorptive Operation • Sleeve Gastrectomy (SG) provides the restriction. • Large portion of the small intestine is bypassed  150-200 cc gastric sleeve which is connected to the remainder of the small intestine • Excluded portion of the small intestine is attached 100 cm to the ileocecal valve. • Serves as the conduit for bile and pancreatic juices

13. Biliopancreatic Diversion with Duodenal Switch (BPD-DS):

14. Roux-en-Y Gastric Bypass (RYGB): • Primarily performed laparoscopicaly through 5-7 trocar sites. • Surgical stapler creates a small, stomach pouch. • Containing only food particles. • Bowel beyond the stomach pouch contains both food particles and digestive juices.

15. Roux-en-Y Gastric Bypass (RYGB):

16. Methods: • The following databases were used: • CINAHL, Web of Knowledge, Medline, Google Scholar • The terms “bariatric surgery” and “diabetes treatment” were entered. • To limit the search Boolean logical operators, source type, date of publication, language, study participants, and the truncation of terms were used. • A total of 27 articles were referenced

17. Resolution of Diabetes after LAGB: • Dixon et al. • 50 participants with T2DM, followed for 1 year post-operative • Remission of T2DM was defined as (normal HbA1c levels, without pharmaceutical therapy). • Results: • 64% of participants achieved T2DM remission • 26% noted improvement in glycemic control • 10% remained unchanged

18. Resolution of Diabetes after LAGB: • Dixon: Later Study • Randomized-controlled study • Intervention: • LAGB (experimental group) or diet and exercise (control group) • Results: • 73% of participants who received LAGB demonstrated T2DM remission. • 13 % of the participants in the control group demonstrated T2DM remission.

19. Resolution of Diabetes after LAGB: • Ponce et al. • 402 LAGB patients were reviewed. • Preoperatively 53 out of the 402 patients were on hypoglycemic medication for T2DM • Results: • T2DM resolution in 66% of patients at the 1 year mark • T2DM resolution in 80% of patients at the 2 year mark

20. Resolution of Diabetes after BPD-DS: • Scopinario • Looked at 2,241 BPD patients and determine 100% of those of T2DM had resolution (4 months postoperative) • Scopinario: 2008 Study • Comparison of RYGB and BPD. • Data from 443 patients with T2DM between the years of 1976 and 2007 were collected • Results: • 75% of patients were in remission 2 months postoperative. • Remained stable for almost a 20 year period

21. Resolution of Diabetes after SG: • University of Pittsburgh (2006): • 126 patients • Results: • 1 year postoperative, 81% of SG patients demonstrated T2DM resolution; 10% showed significant improvement. • Italian Study: • 44 SG patients • Results: • 76% of participants showed T2DM resolution during 19 year follow up • T2DM improvement was reported in 15% of patients

22. Resolution of Diabetes after RYGB: • Pories • 608 RYGB patients (121 had T2DM and 150 had impaired glucose tolerance) • Patients were followed for 14 years postoperatively. • Results: • 83% of the 121 T2DM patients experienced resolution. • 98% of the 150 with impaired glucose tolerance maintained normal levels.

23. Resolution of Diabetes after RYGB: • Swedish Obese Subjects Study Group: • 2004 report included 4,047 postoperative subjects followed for 2 years and 1,703 for 10 years. • Results: • T2DM recovery was reported in 72% of RYGB patients compared to 21% resolution in the medical management group.

24. Limitations: • Many of the studies were uncontrolled case studies with a few being randomized controlled trails.

25. Possible Theories of Resolution: • While the results of the studies were statistically significant, the pathophysiology of the T2DM resolution is not understood. • Combination of weight loss, decreased caloric intake, intestinal malabsorption, hormonal changes, and rearrangement of the gastrointestinal anatomy

26. Effect of Bariatric Surgery on T2DM: • All bariatric surgical procedures induce decreased caloric intake, which has a well established beneficial effect on T2DM. • Glucose homeostasis improves more rapidly after segments of the small bowel are bypassed when compared to restrictive procedures

27. Most Intriguing Fact: • Weight loss does not appear to be the primary mechanism for T2DM resolution after RYGB and BPD-DS. • Most studies noted T2DM resolution occurs within days after surgery before any significant weight loss has occurred.

28. Further Research: • Randomized clinical trials comparing surgical and medical therapies for T2DM are needed. • Due to increasing numbers of diabetes patients undergoing bariatric surgery. • Bariatric surgical procedures should be incorporated into a national clinical registry. • Enable objective assessments of the risk and benefits.