Cost-effectiveness Analysis of Bariatric Surgery for Patients With Nonalcoholic Steatohepatitis Cirrhosis

Abstract

Importance: Obesity is the most common risk factor for nonalcoholic steatohepatitis (NASH), the progressive form of nonalcoholic fatty liver disease that can lead to cirrhosis and hepatocellular carcinoma. Weight loss can be an effective treatment for obesity and may slow the progression of advanced liver disease.

Objective: To assess the cost-effectiveness of bariatric surgery in patients with NASH and compensated cirrhosis.

Design, setting, and participants: This economic evaluation study used a Markov-based state-transition model to simulate the benefits and risks of laparoscopic sleeve gastrectomy (SG), laparoscopic Roux-en-Y gastric bypass (GB), and intensive lifestyle intervention (ILI) compared with usual care in patients with NASH and compensated cirrhosis and varying baseline weight (overweight, mild obesity, moderate obesity, and severe obesity). Patients faced varied risks of perioperative mortality and complications depending on the type of surgery they underwent. Data were collected on March 22, 2017.

Main outcomes and measures: Life-years, quality-adjusted life-years (QALYs), costs (in 2017 $US), and incremental cost-effectiveness ratios (ICERs) were calculated.

Results: Demographic characteristics of the patient population were based on a previously published prospective study (n = 161). Patients in the model were 41.0% female, and the base case age was 54 years. Compared with usual care, SG was associated with an increase in QALYs of 0.263 to 1.180 (bounds of ranges represent overweight to severe obesity); GB, 0.263 to 1.207; and ILI, 0.004 to 0.216. Sleeve gastrectomy was also associated with an increase in life-years of 0.693 to 1.930; GB, 0.694 to 1.947; and ILI, 0.012 to 0.114. With usual care, expected life-years in overweight, mild obesity, moderate obesity, and severe obesity were 12.939, 11.949, 10.976, and 10.095, respectively. With usual care, QALY in overweight was 6.418; mild obesity, 5.790; moderate obesity, 5.186; and severe obesity, 4.577. Sleeve gastrectomy was the most cost-effective option for patients across all weight classes assessed: ICER for SG in patients with overweight was $66 119 per QALY; mild obesity, $18 716 per QALY; moderate obesity, $10 274 per QALY; and severe obesity, $6563 per QALY. A threshold analysis on the procedure cost of GB found that for GB to be cost-effective, the cost of the surgery must be decreased from its baseline value of $28 734 by $4889 for mild obesity, by $3189 for moderate obesity, and by $2289 for severe obesity. In overweight patients, GB involved fewer QALYs than SG, and thus decreasing the cost of surgery would not result in cost-effectiveness.

Conclusions and relevance: Bariatric surgery could be highly cost-effective in patients with NASH compensated cirrhosis and obesity or overweight. The findings from this analysis suggest that it can inform clinical trials evaluating the effect of bariatric procedures in patients with NASH cirrhosis, including those with a lower body mass index.

Figure.. Simplified Model Schematic

The dashed line between the compensated cirrhosis and decompensated cirrhosis states indicates that the probability of decompensating varies according to body mass index and thus decreases with weight loss. ICER indicates incremental cost-effectiveness ratio; QALYs, quality-adjusted life-years.