Bariatric Surgery Coverage: a Comprehensive Budget Impact Analysis from a Payer Perspective

The objective of this study was to estimate a payer's budget impact of bariatric surgery coverage under (1) unrestricted, (2) budget-restricted ($500,000/year), and (3) quantity-restricted (100/year) medical benefit plan scenarios versus non-coverage in general and type 2 diabetes mellitus (T2DM) populations over a 10-year period.

Using recently published literature and health technology assessment reports, the model evaluated a hypothetical payer population of 100,000 members under current real-world trends: BMI-defined obesity groups (31.3% normal/underweight, 33% overweight, 20.4% obese, 9% severely obese and 6.3% morbidly obese), T2DM prevalence (6.7-27.5%; 100% for the T2DM model), surgery type (LAGB, BPD/DS, VSG, and RYGB), and differential outcomes (T2DM resolution, costs, and reoperation and complications rates). Assuming a surgery election rate of 1.42% among eligible candidates with a 3% discount rate and 10% annual surgery turnover rate, the model calculated the incremental cost per-member-per-month (PMPM) by estimating the difference in total non-T2DM and T2DM-related expected costs and savings. One-way (± 25%) sensitivity analysis was performed.

The impact of covering bariatric surgery under multiple scenarios for a general (or T2DM) population ranged from an additional $0.3 to $3.6 (T2DM: $0.3 to $10.5) PMPM in year 1. Incremental costs diminished over time, breaking even between years 5 and 9 (T2DM: 5-6), and by year 10, cost savings were estimated to be between $1.5 and $4.8 (T2DM: $1.2 and $31.8).

Providing bariatric surgery coverage may have a modest short-term budget impact increase but would lead to long-term net cost savings in a general population model. The cost savings were much more pronounced in the T2DM model.