The Business Case for Bariatric Surgery Revisited: A Non-Randomized Case-Control Study

Background and Aim: Prior studies reporting that bariatric surgery (including laparoscopic adjustable gastric band (LAGB) and [laparoscopic Roux-en-Y] Gastric Bypass (LRYGB)) is cost-saving relied on a comparison sample of those with a morbid obesity (MO) diagnosis code, a high cost group who may not be reflective of those who opt for the procedures. We re-estimate net costs and time to breakeven using an alternative sample that does not rely on this code. Materials and Methods: Non-randomized case-control study using medical claims data from a commercial database in the USA. LAGB and LRYGB claimants were propensity score matched to two control samples: one restricted to those with a MO diagnosis code and one without this restriction. Results: When using the MO sample, costs for LAGB and LRYGB are recovered in 1.5 (Confidence Interval [CI]: 1.45 to 1.55) and 2.25 years (CI: 2.07 to 2.43), and 5 year savings are $78,980 (CI: 62,320 to 100,550) for LAGB and $61,420 (CI: 44,710 to 82,870) for LRYGB. Without the MO requirement, time to breakeven for LAGB increases to 5.25 (CI: 4.25 to 10+) years with a 5 year net cost of $690 (CI: 6,800 to 8.400). For LRYGB, time to breakeven exceeds 10 years and 5 year net costs are $18,940 (CI: 10,390 to 26,740). Conclusions: The net costs and time to breakeven resulting from bariatric surgery are likely less favorable than has been reported in prior studies, and especially for LRYGB, with a time to breakeven of more than twice the 5.25 year estimate for LAGB.