The use, safety and cost of bariatric surgery before and after Medicare's national coverage decision

Abstract

Objective: To determine the impact of the Centers for Medicare and Medicaid Services' (CMS) bariatric surgery national coverage decision (NCD) on the use, safety, and cost of care CMS beneficiaries.

Background: In February 2006, the CMS issued a NCD restricting reimbursement for bariatric surgery to accredited centers and including coverage for laparoscopic adjustable gastric band (LAGB).

Methods: A pre/postinterrupted time-series cohort study using nationwide Medicare data (2004-2008) evaluating rates of bariatric procedures/100,000 enrollees, 90-day mortality, readmission rate and payments.

Results: Forty-seven thousand thirty patients underwent procedures at 928 sites pre-NCD and 662 post-NCD. The procedure rate/100,000 patients dropped after the NCD to 17.8 (from 21.9 in 2005) increasing to 23.8 and 29.1 in 2007 and 2008, respectively. Open roux-en-y gastric bypass (ORYGB) and laparoscopic roux-en-y gastric bypass (LRYGB) were common pre-NCD (56.0% ORYGB, 35.5% LRYGB) changing post-NCD with LAGB inclusion (12.8% ORYGB, 48.7% LRYGB, 36.7% LAGB). 90-day mortality pre-NCD was 1.5% (1.8% ORYGB, 1.1% LRYGB) and post-NCD was 0.7% (1.7% ORYGB, 0.8% LRYGB, 0.3% LAGB; P < 0.001). The 90-day rates of readmission decreased post-NCD (19.9% to 15.4%), reoperation (3.2% to 2.1%) and payments ($24,363 to $19,746; P for all <0.001). Differences in outcome and cost were largely explained by a shift in procedure type and patient characteristics.

Conclusions: The NCD was associated with a temporary reduction in procedure rate and a shift in types of procedures and patients undergoing bariatric surgery. It was associated with a significant decrease in the risk of death, complications, readmissions, and per patient payments.

FIGURE 1

Bariatric operations per 100,000 CMS enrollees by quarter, Medicare 2004 to 2008.

FIGURE 2

Number of unique general surgeons performing and sites where bariatric operations took place, by quarter 2004 to 2008.

FIGURE 3

Time series of 90-day mortality rates for the CMS beneficiaries undergoing bariatric surgery. Q denotes quarter, and the fitted trend lines show predicted values for segmented time-series regressions for pre-NCD and post-NCD periods (adjusted only for temporal trends). The shaded bar represent transitional quarter between policy period, not included in this analysis.