COST-EFFECTIVENESS OF BARIATRIC SURGERY IN SEVERELY OBESE PATIENTS

WITH DIABETES

Department of Surgery Journal Club for March 7, 2013

Graphic Demonstration of Differences in Placebo vs Metformin, and Lifestyle Modification in Prevention of Type II DM

Graphic Demonstration of Large Diabetes Prevention Program Study

Ann Surg. 1992 Jun;215(6):633-42; discussion 643.Is type II diabetes mellitus (NIDDM) a surgical disease?

Pories WJ, MacDonald KG Jr, Flickinger EG, Dohm GL, Sinha MK, Barakat HA, May HJ, Khazanie P, Swanson MS, Morgan E, et al.Source

Department of Biochemistry, East Carolina University School of Medicine, Greenville, NC 27834.Abstract

Since February 1, 1980, 515 morbidly obese patients have undergone the Greenville gastric bypass (GGB) operation. Of these, 212 (41.2%) were euglycemic, 288 (55.9%) were either diabetic or had glucose intolerance, and 15 (2.9%) were unable to complete the

evaluation. After the operation, only 30 (5.8%) patients remained diabetic (and 20 of these improved), 457 (88.7%) became and have remained euglycemic, and inadequate data prevented classification of the other 28 (5.4%). The patients who failed to return to normal glucose values were older and their diabetes was of longer duration than those who did. The effect of the GGB was not only limited to the correction of abnormal glucose levels. The GGB also corrected the abnormal levels of fasting insulin and glycosylated hemoglobin

in a cohort of 52 consecutive severely obese patients with non-insulin-dependent diabetes. The GGB effectively controls weight. If morbid obesity is defined as 100 pounds over ideal body weight, 89% of the patients are no longer "morbidly" obese within 2 years. In most patients, the control of the weight has been well maintained during the 11 years of follow-up; most of the upward creep in weight of 20.8% between 24 and 132 months was from the 49 (9.5%) patients who had staple line breakdowns between the large and small

gastric pouches. Non-insulin-dependent diabetes, previously considered a chronic unrelenting disease, can be controlled in the severely obese by the gastric bypass. Whether the correction of glucose metabolism affects the complications of diabetes is unknown. Whether the gastric bypass should be considered for patients with advanced non-insulin-dependent diabetes but who are not severely

obese deserves consideration. The GGB has an unacceptably high rate of staple line failure. Accordingly, the authors have recently changed their procedure to one that divides the stomach rather than partitions it with staples.

STATEMENT: “Gastric bypass is the most effective therapy in the treatment of type 2 diabetes since the discovery of insulin in 1916.”

Abstract

Diabetes Metab. 2009 Dec;35(6 Pt 2):518-23. doi: 10.1016/S1262-3636(09)73459-7.Mechanisms of early improvement/resolution of type 2 diabetes after bariatric surgery.

Mingrone G, Castagneto-Gissey L.

SourceDepartment of Internal Medicine, Catholic University, Rome, Italy. gmingrone@rm.unicatt.it

AbstractBariatric surgery represents the main option for obtaining substantial and long-term weight loss in morbidly obese subjects. In addition,

malabsorptive (biliopancreatic diversion, BPD) and restrictive (roux-en-Y gastric bypass, RYGB) surgery, originally devised to treat obesity, has also been shown to help diabetes. Indeed, type 2 diabetes is improved or even reversed soon after these operations and

well before significant weight loss occurs. Two hypotheses have been proposed to explain the early effects of bariatric surgery on diabetes--namely, the hindgut hypothesis and the foregut hypothesis. The former states that diabetes control results from the more rapid delivery of nutrients to the distal small intestine, thereby enhancing the release of hormones such as glucagon-like peptide-1

(GLP-1). The latter theory contends that exclusion of the proximal small intestine reduces or suppresses the secretion of anti-incretin hormones, leading to improvement of blood glucose control as a consequence. In fact, increased GLP-1 plasma levels stimulate insulin secretion and suppress glucagon secretion, thereby improving glucose metabolism. Recent studies have shown that improved intestinal

gluconeogenesis may also be involved in the amelioration of glucose homoeostasis following RYGB. Although no large trials have specifically addressed the effects of bariatric surgery on the remission or reversal of type 2 diabetes independent of weight loss and/or

caloric restriction, there are sufficient data in the literature to support the idea that this type of surgery--specifically, RYGB and BPD--can lead to early improvement of glucose control independent of weight loss.

Copyright 2009 Elsevier Masson SAS. All rights reserved.

DEFINITION OF QALY

• Quality-adjusted life-years-- QALYs

• For diabetes, it means a year without three microvascular complicatons: nephropathy, neuropathy and retinopathy

• In terms of macrovascular events, it means a year without CAD (MI or angina) or stroke.

• It requires that the patient’s DM be in remission

DO YOU HAVE PROBLEMS WITH PAPER’S METHODS?

DOES BARIATRIC SURGERY PROVIDE COST-SAVINGS IN THE TREATMENT OF

DIABETES?

DOES YOUR MODERATOR (Dr. Kellum) know how to construct a simulation model to compare two operations and two

disease states (New onset DM vs established DM) for cost effectiveness?

• ANSWER: A resounding, NO!

Assumptions in this Paper

• Somewhere back there the authors had real patients who either had surgery or not

• Authors admit analysis had limitations in that it only measured a few benefits of surgery including remission, BP, and cholesterol levels.

• Assumes a QoL improvement directly associated with BMI loss only.