Actual Medical and Pharmacy Costs for Bariatric Surgery

6-Year Follow-Up

Valerie H. Myers, PhD; Megan A. McVay, PhD; Claire E. Adams, PhD; Brooke L. Barbera, PhD; Meghan M. Brashear, MPH; William D. Johnson, PhD; Patricia Smith Boyd, BA; Phillip J. Brantley, PhD


South Med J. 2012;105(10):530-537. 

In This Article

Abstract and Introduction


Objective: To determine the change in total medical expenditures, total pharmacy expenditures, and subcategories of medical and pharmacy expenditures in obese individuals following weight loss surgery (WLS), and to compare these costs with expenditures in obese individuals not receiving WLS.
Methods: Louisiana Office of Group Benefits (OGB), the state-managed health insurer, invited members to be evaluated for insurance-covered WLS. Of 951 obese members who provided written consent to begin the WLS screening process, 40 were selected for surgery. Medical and pharmaceutical claims cost data of the 911 patients who did not have surgery and the 39 individuals who completed surgery were compared over a 2-year presurgical and 6-year postsurgical period.
Results: Total nonpharmacy medical costs were lower for WLS patients compared with non-WLS patients beginning 4 years postsurgery and lasting through 6 years postsurgery. No differences were found between WLS and non-WLS patients in expenditures for most medical subcategories examined, including emergency department, physical and occupational therapy, office visits, and laboratory/pathology; whereas sleep facility and all remaining medical expenditures not represented by a subcategory were lower for WLS patients during some postsurgery years. Total pharmacy costs were lower for WLS participants at 2 and 3 years postsurgery, but these lower costs were not maintained; however, costs remained lower for antidiabetic agents, antihypertensive agents, and dyslipidemic agents through all 6 postsurgery years under study.
Conclusions: The cost of WLS may begin to be recouped within the first 4 years postsurgery with continued effects 6 years postsurgery.


Weight loss surgery (WLS) has proven effective at producing substantial weight loss and reducing obesity-related comorbidities, including diabetes mellitus, hypertension, and hypertriglyceridemia.[1–3] A meta-analysis estimated that WLS results in the loss of 55.9% of excess body weight and the resolution of diabetes mellitus in 78.1% of patients.[3] Individuals who have had WLS have lower mortality rates than do obese controls.[4]

WLS has received attention for its potential to reduce the high healthcare costs associated with obesity. Research suggests that individuals with obesity have medical costs that are 42% greater than normal-weight individuals.[5] Extreme obesity (body mass index [BMI] >40 kg/m2) engenders even greater costs. Medical expenditures for severely obese individuals are estimated to be 81% greater than those for normal-weight individuals, equivalent to an additional $2845 cost per person per year.[6] Recent analyses have estimated that obesity accounts for 16.5% of national healthcare spending.[7] The costs of obesity are expected to continue to grow during the next decade.[8]

Researchers have described the economic impact of WLS. Finkelstein and Brown used an economic simulation model and estimated that WLS costs would be recouped within 5 to 10 years after surgery due to reductions in medical and other obesity-associated costs.[9] Some researchers, however, have reported an even more rapid return on investment following WLS.[10,11] Cremieux and colleagues[10] used a private health insurance database of claims to compare 3651 WLS patients to matched obese controls who had not undergone WLS. They found WLS patients had lower medical costs beginning 3 months postsurgery, and a return on investment after 2 years for laparoscopic surgery and 4 years for open surgery. One limitation of the Cremieux et al study was that actual cost data were available only for the initial 18 months on average; costs for the remaining months were estimated.

Whereas Cremieux and colleagues[10] compared WLS patients to obese, nonsurgical controls and found a rapid return on investment, other studies not using a comparison control group have reported either no change or an increase in medical costs following WLS.[12–14] McEwen and colleagues[14] found that WLS patients' per-month costs were greater 13 to 24 months postsurgery compared with 6 to 18 months before surgery. These results suggest that whereas WLS may not result in a presurgical to postsurgical reduction in medical expenditures, the costs of health care for obese individuals who are not receiving surgery continue to rise over time. Thus, when comparing WLS patients' postsurgical costs with those of obese individuals not receiving surgery, WLS appears to result in a relative reduction in medical expenditures and a return on investment, possibly within a few years postsurgery. There is a need for data on actual medical expenditures extending beyond 2 years postsurgery, along with comparison with obese individuals who have not undergone surgery.

In addition to a need for data on overall costs, it would be beneficial to identify the specific medical service categories that are subject to change following WLS. Typically, obese individuals have elevated prescription drug costs,[5] thus the effects of WLS on prescription drug expenditures have been of interest. Substantial and rapid decreases in pharmaceutical use and associated costs following WLS have been reported in multiple studies.[15–17] Snow and colleagues[16] showed that pharmacy costs decreased from $369 per patient per month before WLS to $119 per patient per month at 6 months postsurgery. WLS also has been shown to reduce the likelihood of initiating medication use. In the Swedish Obese Subjects (SOS) study, WLS patients were five times less likely to begin medication for diabetes mellitus than control patients during a 6-year period.[15] As with total medical care costs, however, few studies have reported pharmacy costs beyond the first few years postsurgery.

The costs of other nonpharmacy medical subcategories also have received attention. A few studies have suggested that WLS does not lead to a reduction in the frequency and associated cost of hospitalization.[18,19] Zingmond and colleagues[19] found that hospital admissions increased from 8.4% the year presurgery to 20.2%, 18.4%, and 14.9% in the first, second, and third year postsurgery, respectively. Consistent with these data, McEwen et al[14] reported that inpatient care expenditures increased in the 2 years after WLS and the cost of laboratory testing increased during the first year postsurgery. Keating et al[20] found no difference in WLS patients and control patients for outpatient medical pathology test costs in the 2 years after WLS.

Questions remain about the changes in medical and pharmacy care costs following WLS, particularly beyond 2 years postsurgery, as well as the specific medical and pharmacological subcategories in which cost changes are evident. To date, no studies have presented actual cost data following WLS for a state-managed health insurance agency. The present study examined these questions using data from the Louisiana Office of Group Benefits (OGB), Louisiana's managed medical insurance program for state employees and their dependents. OGB services approximately 240,000 individuals. In 2003, OGB collaborated with the Louisiana State University School of Medicine to examine whether WLS could be performed in a controlled setting in which health outcomes and risks could be evaluated.

The objective of the present study was to examine changes in medical care costs for a group of individuals who underwent WLS and to compare these costs with an extremely obese control group spanning the period 2 years presurgery and 6 years postsurgery. In addition to total costs, we analyzed costs in specific classes of medical services and prescription drugs to identify those expenditures that change following WLS.