Public release date: 2-Oct-2003
Contact: Frank Raczkiewicz [email hidden] 412-647-3555 University of Pittsburgh
Medical Center
Gastric bypass surgery resolves or improves diabetes in most patients, reports Pittsburgh study
PITTSBURGH, Oct. 2 – A study of obese people with type 2 diabetes who underwent laparoscopic gastric
bypass surgery (LGBP) found that 83 percent of them experienced a resolution of their disease. The
study, from the University of Pittsburgh School of Medicine, is in the October issue of the journal
Annals of Surgery.
The study also found that clinical resolution or improvement in diabetes occurred in all patients,
but patients with the shortest duration and mildest form of type 2 diabetes had a higher rate of
resolution after the surgery. During the study there were no new occurrences or recurrences of type
2 diabetes in 310 patient years of follow-up. Nearly one third of patients permanently discontinued
anti-diabetic medications after discharge from the hospital – even before significant weight loss
could occur.
According to Philip Schauer, M.D., director of bariatric surgery at the University of Pittsburgh,
principal investigator in the study and co-director of the Minimally Invasive Surgery Center at the
University of Pittsburgh Medical Center, the study suggests that early surgical intervention is
warranted to increase the likelihood of rendering these patients euglycemic.
"Most patients in the study with type 2 diabetes who underwent bypass surgery achieved excellent
biochemical glycemic control and were able to reap the clinical benefits of withdrawing from most,
if not all, anti-diabetes medications, including insulin," Dr. Schauer said. "Younger diabetes
patients with less severe disease stand to gain more from the surgery by circumventing years of
progressive, debilitating disease."
The study included 1,160 patients who underwent Roux-en Y gastric bypass surgery (LGBP) between 1997
and 2002 at the University of Pittsburgh Medial Center. Of those patients, 240 had impaired fasting
glucose and type 2 diabetes. Follow-up was possible in 190. The mean age at surgery was 48 years and
75 percent of the patients were female. Mean body mass index was 50.
"Prior to surgery, the disease severity for these patients was quite significant overall," said
Dr. Schauer, "with 65 percent of them requiring oral agents and 27 percent of them requiring
insulin as well."
Post surgery, patients had a mean excess weight loss of 60 percent and a body mass index of 34 after
20 months. Fasting plasma glucose and glycoslated hemoglobin concentrations returned to normal
levels in 83 percent of patients, while 17 percent of patients markedly improved. Following surgery,
80 percent of patients had a significant reduction in the use of oral anti-diabetic agents and 79
percent had a reduction in their use of insulin.
"The impressive effect of bypass surgery on morbidly obese patients with type 2 diabetes raises an
argument for lowering the threshold for surgical intervention to moderate or mild obesity," Dr.
Schauer said. "Further investigation demonstrating risk versus benefit for patients with moderate
obesity is warranted."
The LGBP procedure involves constructing a small stomach pouch of approximately 15 millimeters
(about the size of a plastic medicine cup), and bypassing a small segment of intestines by
constructing a Y-shaped limb of small bowel. Patients lose weight because there is a decrease in
caloric intake resulting from the reduced reservoir capacity of the small stomach pouch.
Type 2 diabetes is the most common form of diabetes, in which the body is unable to properly use the
insulin that it produces. About 80 percent of people with type 2 diabetes are overweight.
Exactly a year ago there was another study from UCLA.
Arch Surg. 2002 Oct;137(10):1109-17. Related Articles, Links
Effects of obesity surgery on non-insulin-dependent diabetes mellitus.
Greenway SE, Greenway FL 3rd, Klein S.
Department of Surgery, Harbor-University of California, Los Angeles Medical Center, Torrance, CA
90509, USA.
CONTEXT: Most individuals who have non-insulin-dependent diabetes mellitus are obese. The obese
population has proved a frustrating entity regarding weight loss and diabetes control. Results of
medical weight loss programs, medications, and behavior therapy have proved disappointing.
HYPOTHESIS: Bariatric surgery is the most effective method of diabetes management and cure in the
morbidly obese population. Surgical procedures to cause malabsorption provide a more dramatic effect
on diabetes owing to the imparted bypass of the hormonally active foregut. DATA SOURCES: Pertinent
journal articles spanning the last 40 years, as well as textbooks. CONCLUSIONS: Bariatric surgical
procedures have proven a much more successful method of weight loss and diabetes control in the
obese population than conservative methods. These surgical procedures have proven safe with reported
mortality rates of 0% to 1.5%. Bariatric operations may be divided based on the method of weight
loss and effect on diabetes. The first category is restrictive and includes vertical banded
gastroplasty and adjustable silicone gastric banding. These operations improve diabetes by
decreasing food intake and body weight with a slowing of gastric emptying. The second category not
only contains restrictive components but also elements of malabsorption. This category includes the
Roux-en-Y gastric bypass and biliary-pancreatic diversion, which bypass the foregut. Although all of
the surgical procedures for obesity offer improved weight loss and diabetes control compared with
conservative methods, the Roux-en-Y gastric bypass and biliary-pancreatic diversion offer superior
weight loss and resolution of diabetes. The more dramatic effect seen in the surgical procedures to
cause malabsorption is likely secondary to the bypass of the foregut resulting in increased weight
loss and elevation of the enteroglucagon level.
Publication Types: Review Review, Tutorial
PMID: 12361414 [PubMed - indexed for MEDLINE]