Bariatric Surgery and Long-Term Healthcare Costs

It is estimated that the cost of obesity and obesity-related comorbid conditions in the United States is $168 billion, 16.5% of US health expenditures. Bariatric surgery is a recognized treatment for obesity that leads to considerable weight loss and improvements in patient health.

There are differences in results of studies of the impact of bariatric surgery on a patient’s healthcare costs over time: several studies have found decreases in healthcare expenditures, and others have suggested that there may be a return on investment in 3 to 7 years. Two recent follow-up studies were unable to find an association between surgical intervention and overall cost or healthcare utilization savings over time; drug costs did appear to be lower after surgery.

Many public and commercial health insurance plans cover bariatric surgery because of its potential to improve health and lower costs. There has been an increase in the number of bariatric surgical procedures in recent years, with laparoscopic approaches increasing in popularity. However, according to researchers, there are uncertainties about whether and when a return on investment can be expected, what type of bariatric surgery procedure leads to the most cost reductions, and whether cost reductions are sustained over time.

To provide a comprehensive, multiyear analysis of healthcare costs in a large cohort of patients with private insurance who underwent bariatric surgery, surgery patients were matched with a nonsurgical control cohort. The study also analyzed patterns of cost over time by type of surgical procedure. Study results were reported online in JAMA Surgery [doi:10.1001/jamasurg.2013.1504].

The longitudinal analysis of 2002-2008 claims data from 7 Blue Cross and Blue Shield health insurance plans with a total enrollment of >18 million individuals included 29,820 plan members who underwent bariatric surgery between January 1, 2002, and December 31, 2008. These members were matched 1:1 with a comparison group of plan members not undergoing surgery, but with diagnoses closely associated with obesity.

Primary outcome measures were standardized costs (overall and by type of care) and adjusted ratios of the surgery group’s costs relative to those of the comparison group.

The 2 groups were well matched based on age, sex, coverage, and obesity propensity score percentile rankings. The surgery group included more individuals diagnosed as having hypertension during the study period and the comparison group included more individuals with diabetes. The total costs for the 2 groups were within 8% of each other during the preoperative/preindex period.

Over the course of the study, surgery trends shifted. In 2002, 72% of surgical procedures were open bypass; in 2005, laparoscopic surgery was dominant. In 2004, Current Procedural Terminology codes were added for laparoscopic bariatric surgery, greatly decreasing the percentage of unknown type of surgery.

In the surgery cohort, standardized total cost of the surgery for all types of bariatric surgery combined was $29,517, including the costs of surgical admission ($27,833) and the 30-day follow-up period ($1684). Total costs for the surgery group peaked in the second year following surgery and then leveled off. In no postoperative period did they decrease below the overall annual costs seen in the preoperative period.

When the researchers analyzed the unadjusted costs by subcategory, they found a 30% decrease in pharmacy costs during the 3 years following surgery; there was no such reduction in pharmacy costs in the comparison group.

The adjusted total expenditures for patients in the surgery group were comparable to those in the comparison group, with the exception of postoperative/postindex periods 1 and 2, when the surgery group’s total costs were higher than those for the comparison group. Among the 4 cost subcategories (inpatient, physician services in an office setting, pharmacy costs, and all of the claims for non-inpatient services), inpatient costs were significantly higher for the surgery group relative to the comparison group.

With the exception of professional office costs in postoperative/postindex period 6, the pharmacy and office costs were significantly lower for the surgery group than for the comparison group. Patients in the surgery group who underwent laparoscopic surgery had lower costs in the first few years after surgery, but those differences did not persist.

In summary, the researchers said, “Bariatric surgery does not reduce overall healthcare costs in the long term. Also, there is no evidence that any one type of surgery is more likely to reduce long-term healthcare costs. To assess the value of bariatric surgery, future studies should focus on the potential benefit of improved health and well-being of persons undergoing the procedure rather than on cost savings.”