Study identifies factors associated with poor weight loss after gastric bypass surgery

September 15, 2008

Individuals with diabetes and those whose stomach pouches are larger appear less likely to successfully lose weight after gastric bypass surgery, according to a report in the September issue of Archives of Surgery.

Roux-en-Y gastric bypass surgery is the most common bariatric procedure in North America, according to background information in the article. During the procedure, surgeons create a smaller stomach pouch that restricts food intake and bypasses large sections of the digestive system.

"When performed in high-volume centers and with a low rate of complications, gastric bypass provides sustained and meaningful weight loss, significant improvement in quality of life, improvement or resolution of obesity-associated comorbidities and extended life span," the authors write. "However, 5 percent to 15 percent of patients do not lose weight successfully, despite perceived precise surgical technique and regular follow-up."

Guilherme M. Campos, M.D., and colleagues at the University of California, San Francisco, examined data from 361 patients who underwent gastric bypass at one institution between 2003 and 2006. Poor weight loss was defined as losing 40 percent or less of excess body weight after 12 months and good weight loss as losing more than 40 percent of excess weight.

Twelve-month follow-up data were available for 310 of the patients, who had an average body mass index (BMI) of 52 before surgery. At follow-up, they had an average BMI of 34 and had lost an average of 60 percent of their excess body weight. A total of 38 patients (12.3 percent) had poor weight loss. After adjusting for other related factors, diabetes and having a larger size of the stomach pouch after gastric bypass surgery were independently associated with poor weight loss.

Individuals with diabetes may take insulin or other drugs that stimulate the production of fat and cholesterol, the authors note. "Other factors that may lead to weight gain in patients with diabetes include a 'protective' increase in caloric intake to treat episodes of hypoglycemia [low blood sugar], reduction of urinary glucose losses and sodium and water retention that are a direct effect of insulin on the distal tubule in the kidney," the authors write.

The restriction on dietary intake imposed by a small stomach pouch is one of the most important aspects of gastric bypass surgery, they note. Surveys suggest that many surgeons estimate pouch size using anatomical landmarks rather than using a sizing balloon. "As the use of gastric bypass continues to grow, we believe it is critical to stress the importance of and to teach the creation of the small gastric pouch and to better standardize the technique used for pouch creation," the authors write.

Source: JAMA and Archives Journals

Explore further: Weight loss surgery's effects on bone marrow fat and bone mass

Related Stories

Weight loss surgery's effects on bone marrow fat and bone mass

August 9, 2017
Bone marrow fat is thought to regulate bone metabolism, and high levels of marrow fat are seen in states of low bone mass, severe underweight, and diabetes. In a study of obese women undergoing gastric bypass surgery, increases ...

Benefits of gastric bypass surgery linked to changes in sweet taste preference

July 18, 2017
Worldwide, the number of patients struggling with obesity is rapidly increasing in both adults and children. Diet and exercise are the mainstays of treatment for obesity, but have limited effectiveness. While bariatric surgery ...

Delaying bariatric surgery until higher weight may result in poorer outcomes

July 26, 2017
Obese patients who underwent bariatric surgery were more like to achieve a body mass index (BMI) of less than 30 one year after surgery if they had a BMI of less than 40 before surgery, according to a study published by JAMA ...

Monitoring fluid intake may help improve outcomes for bariatric surgery patients

July 24, 2017
Nurses on the bariatric surgery care team at a Connecticut hospital were having difficulty keeping track of patients' fluid intake after hospital admission. To standardize this process, and to avoid patient readmission following ...

Following gastric band surgery, device-related reoperation common, costly

May 17, 2017
Among Medicare beneficiaries undergoing laparoscopic adjustable gastric band surgery, reoperation was common, costly, and varied widely across hospital referral regions, according to a study published by JAMA Surgery.

Dramatic shift in gut microbes and their metabolites seen after weight loss surgery

May 26, 2017
Obesity, already a global epidemic, is on the rise. Over one third of the U.S. population is currently afflicted, according to the Centers for Disease Control and the monetary costs alone are approaching $150 billion dollars ...

Recommended for you

Drug therapy from lethal bacteria could reduce kidney transplant rejection

August 3, 2017
An experimental treatment derived from a potentially deadly microorganism may provide lifesaving help for kidney transplant patients, according to an international study led by investigators at Cedars-Sinai.

Exploring the potential of human echolocation

June 25, 2017
People who are visually impaired will often use a cane to feel out their surroundings. With training and practice, people can learn to use the pitch, loudness and timbre of echoes from the cane or other sounds to navigate ...

Team eradicates hepatitis C in 10 patients following lifesaving transplants from infected donors

April 30, 2017
Ten patients at Penn Medicine have been cured of the Hepatitis C virus (HCV) following lifesaving kidney transplants from deceased donors who were infected with the disease. The findings point to new strategies for increasing ...

'bench to bedside to bench': Scientists call for closer basic-clinical collaborations

March 24, 2017
In the era of genome sequencing, it's time to update the old "bench-to-bedside" shorthand for how basic research discoveries inform clinical practice, researchers from The Jackson Laboratory (JAX), National Human Genome Research ...

The ethics of tracking athletes' biometric data

January 18, 2017
(Medical Xpress)—Whether it is a FitBit or a heart rate monitor, biometric technologies have become household devices. Professional sports leagues use some of the most technologically advanced biodata tracking systems to ...

Financial ties between researchers and drug industry linked to positive trial results

January 18, 2017
Financial ties between researchers and companies that make the drugs they are studying are independently associated with positive trial results, suggesting bias in the evidence base, concludes a study published by The BMJ ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.