CINCINNATI—With figures showing one-third of the United States population as obese, a new study at the University of Cincinnati shows that gastric bypass surgery could improve life expectancy for those who are morbidly obese patients.
This study is being published in the January 2010 Archives of Surgery, aJournal of the American Medical Association (JAMA) archives journal.
In gastric bypass surgery, the stomach is made smaller by creating a pouch at the top of the stomach using surgical staples. The smaller stomach is connected directly to the middle portion of the small intestine, bypassing the rest of the stomach and the upper portion of the small intestine. This leads to weight loss due to decreased appetite and absorption of less food.
Recent figures from the National Center for Health Statistics showed 34 percent of American adults age 20 and older were obese in 2007-08, while 68 percent were considered overweight or obese.
A research team led by Daniel Schauer, MD, assistant professor of medicine and UC Health physician, found that while not all patients are guaranteed a good outcome from the surgery, gastric bypass increases life expectancy for most patients.
“Morbid obesity, defined as having a body mass index (BMI) of 40 or more or weighing 100 pounds above ideal body weight, continues to be a growing problem in the United States, affecting more than 5 percent of the population. This leads to an increase in health care costs of more than $11 billion,” he says. “While gastric bypass surgery has been proven to be effective in reducing obesity and obesity-associated conditions, clinical trials have not identified characteristics of the ‘ideal surgical candidate.’
“Our goal was to better characterize obesity-related deaths and the risks of gastric bypass surgery and then create a model to estimate the balance between treatment risks and benefits for individual patients.”
Schauer and his team developed a series of models to evaluate gastric bypass surgery versus no surgery for morbidly obese patients. Using several large nationally representative data sources—the 2005 National Inpatient Survey and the 1991–96 National Health Interview Survey—and a recent large clinical trial, Schauer was able to create a decision, or simulation, model to estimate the change in life expectancy associated with gastric bypass surgery.
Based on the average morbidly obese patient seeking surgery—a 275-pound, 42-year-old woman (BMI of 45)—nearly three years of life expectancy were gained with gastric bypass surgery.
Schauer stressed that the model can be used to predict changes in life expectancy across a wide range of ages and levels of obesity for both men and women.
“The optimal decision for individual patients needs to be based on the balance of risk between surgical mortality, mortality associated with an increased body mass index and how effective the surgery is for the individual,” he adds. “However, we demonstrate that for the average morbidly obese patent, gastric bypass improves life expectancy. Not all patients will experience the same benefits from gastric bypass surgery, but our analysis helps patients and their doctors understand these potential gains or losses in clinically meaningful terms based upon their specific characteristics, including BMI, age and gender.”
Schauer says he hopes that these results will help to optimize the care of individuals struggling with obesity and will help in saving and creating better lives.
“We believe results of this analysis can be used to better inform both patients’ and physicians’ decisions regarding gastric bypass surgery,” he says.
This study was funded by a grant from the National Institute of Diabetes and Digestive and Kidney Diseases.