Both Gastric Banding and Bypass Surgery Reduce Medical Costs Interview with:
Kristina H. Lewis, MD, MPH, SM
Kaiser Permanente Georgia, Center for Clinical and Outcomes Research, Atlanta
Department of Population Medicine
Harvard Medical School/Harvard Pilgrim Health Care Institute, Boston, Massachusetts

Medical Research: What is the background for this study?

Dr. Lewis: The prevalence of severe obesity (BMI ≥40 kg/m2) in the U.S. is rising. This is concerning, because patients with severe obesity tend to be sicker and have higher healthcare costs.  Bariatric surgery produces substantial weight loss and remission of a number of obesity-related comorbidities, but there have been very few studies directly comparing current procedure types. This leaves patients, providers and insurers with little information to help them decide about the pros and cons of different surgeries.

We wanted to compare outcomes after two of the most common bariatric surgeries in the US – laparoscopic adjustable gastric banding (band) and laparoscopic roux-en-y gastric bypass (bypass). To do this, we examined commercial claims data from almost 10,000 U.S. band and bypass patients who were very similar with respect to age, gender, and medical conditions. We looked at what happened to these patients from one year before their surgeries through 3 years after surgery. We compared changes in medical costs and use of healthcare services before and after surgery.

Medical Research: What are the main findings?

Dr. Lewis: When performed laparoscopically, both gastric bypass and adjustable gastric banding appear to result in lower total medical costs after surgery.  Bypass patients see a greater immediate drop in prescription drug costs than band patients – this is not surprising given that we know that this surgery is more likely to induce weight loss and diabetes remission. Unfortunately, bypass patients also have an initial increase in emergency department visits after surgery that is not present for banding patients.

When we compared total annual medical costs between band and bypass, we found no difference between procedures in the first 2 years after surgery. But, by year 3, bypass patients’ total annual medical costs are about 16% lower than those for band patients.

Medical Research: What should clinicians and patients take away from your report?

Dr. Lewis: Patients and clinicians considering one of these procedures should see these findings as good news. On balance, it looks like, for a group of very sick patients whose annual medical costs are trending upwards before surgery, these procedures result in overall lower levels of healthcare use after they are performed. Deciding between the two procedures, or opting for even newer procedure types, such as sleeve gastrectomy, would require a conversation between patients and their providers about their specific medical needs and their personal health goals.

Medical Research: What recommendations do you have for future research as a result of this study?

Dr. Lewis: Studies are needed that examine the newer “vertical sleeve gastrectomy” procedure in a similar fashion. That procedure has become very popular in the U.S. recently but very little is known about longer-term outcomes after it.  Also – formal cost effectiveness studies that weigh the costs of the procedures against any potential benefits to patients would be important to conduct.


Lewis KH, Zhang F, Arterburn DE, Ross-Degnan D, Gillman MW, Wharam J. Comparing Medical Costs and Use After Laparoscopic Adjustable Gastric Banding and Roux-en-Y Gastric Bypass. JAMA Surg. Published online June 03, 2015. doi:10.1001/jamasurg.2015.1081.


[wysija_form id=”3″]

Kristina H. Lewis, MD, MPH, SM, Kaiser Permanente Georgia, Center for Clinical and Outcomes Research, Atlanta, Department of Population Medicine,  Harvard Medical School/Harvard Pilgrim Health Care Institute, Boston, Massachusetts (2015). Both Gastric Banding and Bypass Surgery Reduce Medical Costs 

Last Updated on June 12, 2015 by Marie Benz MD FAAD