Bariatric surgery doesn’t reduce long-term health care costs, according to a report in the June issue of JAMA Surgery.
In a 6-year follow-up study comparing nearly 30,000 patients who underwent bariatric surgery against the same number of well-matched patients who did not have the surgery, the surgery group showed decreases in costs for office visits and prescriptions, but these were offset by their significant increases in inpatient costs, said Jonathan P. Weiner, Dr.P.H., of the department of health policy and management, Johns Hopkins Bloomberg School of Public Health, Baltimore, and his associates.
Health care costs for the bariatric surgery patients did fall off somewhat during the fourth, fifth, and sixth years following the operation, but not enough to outweigh the expenses incurred during the first 3 postoperative years, the investigators said.
Taken together with the results of two other recent studies of the total health care costs related to bariatric surgery, these findings indicate that "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," they noted.
It seems intuitive that bariatric surgery, which produces considerable weight loss and alleviates or eliminates many obesity-related disorders such as hypertension and diabetes, would of course save future health care costs, at least in the long term. But studies of the impact of the procedure on such costs have shown mixed results.
"Many uncertainties remain about whether and when a return on investment can be expected, which type of bariatric surgical procedure produces the greatest cost reduction, and whether cost reductions are sustained over time," Dr. Weiner and his colleagues said.
To clarify the issue, they analyzed health care costs in a large cohort of privately insured people covered by seven Blue Cross Blue Shield plans in seven states, of which 29,820 underwent a variety of bariatric procedures during a 6-year period. Each of these subjects was matched for age, sex, area of residence, and 33 markers of obesity with a control subject who did not have bariatric surgery.
Surgical trends shifted during the course of the study. At the beginning, 72% of the procedures were open gastric bypass operations; by the end, laparoscopic procedures were predominant.
Although laparoscopic operations were associated with lower costs in the short term than other procedures, this advantage lasted only for a brief period. So overall, health care costs were not significantly different by type of bariatric surgery.
In an unadjusted analysis of the data, the surgical group showed an approximately 30% decrease in pharmacy costs during the first 3 years after the procedure. The control group showed no such drop.
However, the surgical group had significantly more hospital admissions for GI-related diagnoses than the control group during all 6 years of follow-up, which were concentrated during the second and third years following the procedure. Most of these admissions likely were for surgery-related complications, the investigators said.
In an analysis that adjusted for multiple possible confounders, inpatient costs remained higher for the surgical group than the control group throughout follow-up, but particularly during year 2 and year 3 following the procedure. Pharmacy and office visit costs were significantly lower for the surgery group but did not offset the excess in inpatient costs, Dr. Weiner and his associates reported (JAMA Surg. 2013;148:555-61).
This study "adds substantially to the existing literature on cost of bariatric surgery" because the study population was the largest to date and was representative of a broad cross section of the commercially insured U.S. population. The study also boasts one of the longest follow-ups of bariatric surgery outcomes in the United States, since previous studies generally had follow-ups of only 6 months to 2 years, the researchers said.
In a Clinical Review & Education piece accompanying this report (JAMA Surg. 2013;310:742-3), Matthew L. Maciejewski, Ph.D., and Dr. David E. Arterburn said that bariatric surgery may still be cost-effective even if it is not cost-saving.
"Does bariatric surgery need to be cost-effective (i.e., more effective but more costly than usual care), or does it need to achieve the higher standard of cost savings (i.e., more effective and less costly than usual care) to justify broader insurance coverage?" they asked.
The procedures are so expensive that they are unlikely to meet the threshold of "cost saving" for most patients. Even if a patient’s total health care costs are cut by half after the surgery, "it may take up to 20 years to achieve cost neutrality," said Dr. Maciejewski of the Center for Health Services Research in Primary Care, Durham (N.C.) VA Medical Center, and Dr. Arterburn of the Group Health Research Institute, Seattle.