Office of Research & Development

 

Feature Article

Weight-loss surgery: Does it save health-care costs in the long run?

Bariatric surgery involves surgery on the stomach, the intestines, or both to help people who are extremely obese lose weight. A new study led by VA researchers has found that the department's costs to treat surgical patients three years after bariatric surgery was similar to its costs to treat Veterans who did not have this kind of surgery.

"Obesity is difficult to treat,"says Matthew L. Maciejewski, PhD, lead author of the study, which was published in the July 2012 issue of Archives of Surgery. i "And bariatric surgery is the most effective means to induce weight loss for the severely obese."

There have been few long-term studies of the health and economic benefits of bariatric surgery, and most studies prior to this Health Services Research and Development (HSR&D)-funded study examined outcomes for younger, primarily white, and female populations.

Maciejewski, who is a researcher at the Center for Health Services Research in Primary Care at the Durham, N.C., VA Medical Center and a professor in the department of medicine at Duke University, set out with his team to determine whether bariatric surgery is associated with reduced health expenditures in older male patients whose health has been affected by their obesity.

In a previous study using the same data set that was published in the Journal of the American Medical Association in 2011, Maciejewski's team had found that bariatric surgery in older males was not significantly associated with a decrease in mortality (death). ii In the new study, they focused only on the economic factors related to the procedure's health outcomes.

The team used VA's electronic health records system and data from the VA Surgical Quality Improvement Program (VASQIP) to review the medical records and VA claims data of 847 Veterans who had had bariatric surgery between 2000 and 2006 at one of twelve VA medical centers nationwide. Their records were compared to those of 847 obese Veterans (those with a body mass index greater than 35) who had not had the surgery, and were matched on the basis of similar demographic and risk characteristics.

Based on results from prior studies, the researchers' working hypothesis was that those who had had the surgery would have lower health expenditures than the control subjects. The majority (nearly 74 percent) of the subjects who underwent surgery were male, many (at least 17 percent) were minorities, and the average age was 49.5 years. The control subject group was selected so that its characteristics almost exactly matched the characteristics of the surgical patients group.

Obesity-associated health expenditures were estimated at $147 billion in 2008. These expenditures are disproportionately higher for morbidly obese patients, and increase with age. Previous studies in this area had found that health care expenditures decreased after bariatric surgery, two to five years after the procedure took place. However, as noted above, those studies examined outcomes in younger, primarily white, and female populations.

The team compared VA inpatient, outpatient and total expenditures between the surgical and non-surgical patients for a six-year period: three years before the surgery took place and three years afterwards.

The study's authors found that inpatient expenditures were slightly higher, and outpatient expenditures slightly lower, for patients who would undergo the surgery three years later, compared to those who would not. Both inpatient and outpatient costs for the surgical group increased significantly in the months before the surgery took place, and then decreased after surgery (sharply for inpatient costs; gradually for outpatient costs) until the last six-month period (31 to 36 months after surgery), when VA health care costs were virtually the same for those who did and did not have surgery.

According to Maciejewski, "These results are notable because they contrast with results from several prior observational studies that found expenditures among post-surgical cases to be lower than those of non-surgical controls two to four years after the procedures. This can be explained by important differences in the populations examined and the methods of analysis."

Bariatric surgery is still a valuable option for treating extremely obese patients, because there are undeniable health benefits. The study concludes that "although bariatric surgery was not associated with reduced expenditures in this cohort of older, predominantly male Veterans, many patients may still choose to undergo bariatric surgery, given the strong evidence of significant reduction in body weight and comorbidities [diseases that occur at the same time as others], and improved quality of life."

The study's authors believe it is possible that expenditures may decline further for surgical cases in the longer term, a hypothesis they will be examining in an ongoing HSR&D-funded follow-up study.

VA offers bariatric surgery for eligible Veterans at many of its medical centers to produce weight loss in chronically obese individuals. According to VA regulations, to be eligible for bariatric surgery, extremely obese Veterans must have demonstrated prior attempts at weight loss and compliance with weight loss measures before being scheduled for surgery, as a predictor of post-operative success.



i ML Maciejewski, EH Livingston, VA Smith, LC Kahwati, WG Henderson, DE Arterburn, "Health Expenditures Among High-Risk Patients After Gastric Bypass and Matched Controls."Arch Surg. 2012;147(7):633-640. Doi:10.1001/archsurg.2012.818

ii ML Maciejewski, EH Livingston, VA Smith et al. "Survival among high-risk patients after bariatric surgery."JAMA 2011;305(23):2419-2426.