University of Pittsburgh Study Finds Surgery for Obesity Most Successful When Performed by the Most Experienced Surgeons
PITTSBURGH, March 21, 2003 The risk of complications following gastric bypass surgery for obesity is significantly lower when performed by a surgeon with greater experience in the procedure, according to a University of Pittsburgh study.
The study, presented today at the Central Surgical Association in Toronto, Canada, by Anita Courcoulas, M.D., assistant professor of surgery at the University of Pittsburgh School of Medicine, and director of bariatric surgery at the University of Pittsburgh Medical Center's Shadyside Hospital, is the first to address the relationship between patient volume and outcome for the rapidly growing and complicated field of gastric bypass surgery.
In the surgery, a small stomach pouch is created to restrict food intake. Then a Y-shaped portion of the small intestine is attached to the pouch to allow food to bypass the lower stomach, the duodenum, and the first section of the jejunum. This bypass reduces the amount of calories and nutrients the body can absorb.
The study found that surgeons performing fewer than 10 bypass procedures per year had a 28 percent risk of adverse outcomes and a 5 percent risk of mortality compared to 14 percent and 0.3 percent, respectively, for high-volume surgeons.
With the introduction of the laparoscopic approach both the complexity and prevalence of these gastric bypass procedures are increasing, said Dr. Courcoulas.
The data used in the study were obtained from the Pennsylvania Health Care Cost Containment Council. Risk factors include age, gender, race, co-morbid medical conditions and illness severity, among others. Over the three year period of the study, gastric bypass surgery in the state increased by 100 percent each year. Of the 4,674 cases studied, females comprised 82 percent of patients, whites made up 70 percent, blacks made up 10 percent, and 20 percent were other races. Ages ranged from 16 to 74 years.
The study data encompassed 73 hospitals and 129 surgeons. There were 28 in-hospital deaths and 813 adverse outcomes during the study period. Nearly 17 percent of patients had one or more postoperative complications that ranged from major to minor while in the hospital following surgery in this study group.
The data showed a clear and significant trend to fewer adverse outcomes with more experienced surgeons, said Dr. Courcoulas. The study also demonstrated several interactions in a risk-adjusted model, between surgeon and hospital volume. Surgeons performing 10 to 50 cases per year, operating in low-volume hospitals had the highest adverse outcome rate of 55 percent. Surgeons performing more than 50 cases a year did not operate in low to medium volume hospitals. The subset of surgeons who performed fewer than 10 cases per year in a medium-volume hospital had the highest increase in mortality with a rate of 7 percent.
Although the relationship between provider volume and outcome for gastric bypass surgery is clear in this study, mortality and complications are only part of the full range of outcome measures that are meaningful after major procedures such as gastric bypass surgery, said Dr. Courcoulas.
These outcome measures include long-term weight loss, improvement in functional status, improved quality of life, patient satisfaction and service quality. These measures of quality of care will need to be more thoroughly investigated in the rapidly growing field of obesity surgery. Future studies, with larger sample sizes, will need to address both volume-outcome relationships and the broad range of clinical outcomes and other multiple factors that influence overall quality of care.