Nonalcoholic steatohepatitis (NASH) affects 2%-3% of the US population and is expected to become the leading indication for liver transplantation in the next decade. Bariatric surgery may be an effective but expensive treatment for NASH. Using a state-transition model, our analysis assessed the effectiveness and cost-effectiveness of surgery to manage NASH. We simulated the benefits and harms of laparoscopic Roux-en-Y gastric bypass surgery in patients defined by weight class (overweight, mild obesity, moderate obesity, and severe obesity) and fibrosis stage (F0-F3). Comparators included intensive lifestyle intervention (ILI) and no treatment. Quality-adjusted life years (QALYs), costs, and incremental cost-effectiveness ratios were calculated. Our results showed that surgery and ILI in obese patients (with F0-F3) increased QALYs by 0.678-2.152 and 0.452-0.618, respectively, compared with no treatment. Incremental cost-effectiveness ratios for surgery in all F0-F3 patients with mild, moderate, or severe obesity were $48,836/QALY, $24,949/QALY, and $19,222/QALY, respectively. In overweight patients (with F0-F3), surgery increased QALYs by 0.050-0.824 and ILI increased QALYs by 0.031-0.164. In overweight patients, it was cost-effective to reserve treatment only for F3 patients; the incremental cost-effectiveness ratios for providing surgery or ILI only to F3 patients were $30,484/QALY and $25,367/QALY, respectively.
Surgery was both effective and cost-effective for obese patients with NASH, regardless of fibrosis stage; in overweight patients, surgery increased QALYs for all patients regardless of fibrosis stage, but was cost-effective only for patients with F3 fibrosis; our results highlight the promise of bariatric surgery for treating NASH and underscore the need for clinical trials in this area. (Hepatology 2017;65:1156-1164).