Obesity is a risk factor for non-alcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC). Bariatric surgery can provide durable weight-loss, but little is known about the later development of NASH and HCC after surgery.

Bariatric surgery (n = 3,410) and obese controls (n = 46,873) from an institutional data repository were propensity score matched 1:1 by demographics, comorbidities, BMI, and socioeconomic factors. Comparisons were made through paired univariate analysis and conditional logistic regression.

Total of 4,112 patients were well matched with no significant baseline differences except initial BMI (49.0 vs 48.2, p = 0.04). Bariatric group demonstrated fewer new-onset NASH (6 0.0% vs 10.3%, p < 0.0001) and HCC (0.05% vs 0.34%, p = 0.03) over a median follow-up of 7.1 years. After risk-adjustment, bariatric surgery was independently associated with reduced development of NASH (OR 0.52, p < 0.0001).

Bariatric surgery is associated with reduced incidence of NASH and HCC in this large propensity matched cohort. This further supports the use of bariatric surgery for morbidly obese patients to ameliorate NASH cirrhosis and development of HCC.

Bariatric surgery is still not recommended to alleviate the long-term sequelae of non-alcoholic fatty liver disease (NAFLD) despite some evidence to suggest bariatric surgery can mitigate the risk of non-alcoholic steatohepatitis (NASH) and/or hepatocellular carcinoma. This current study is the first to use a propensity match analysis of a large cohort of bariatric surgery patients with non-surgery controls to show that patients who had undergone bariatric surgery had fewer new cases of NASH and HCC with extended follow up, and further risk adjustment also revealed bariatric surgery was associated with fewer cases of NASH by 48%. These results highlight the importance of bariatric surgery offering more than a procedure for sustained weight loss, but also in its potential to further abate obesity-related comorbidities, as well.