Bariatric Surgery Provides Long-term Resolution of Nonalcoholic Steatohepatitis and Regression of Fibrosis

Gastroenterology. 2020 Oct;159(4):1290-1301.e5. doi: 10.1053/j.gastro.2020.06.006. Epub 2020 Jun 15.


Background and aims: Studies are needed to determine the long-term effects of bariatric surgery for patients with nonalcoholic steatohepatitis (NASH). We evaluated sequential liver samples, collected the time of bariatric surgery and 1 and 5 years later, to assess the long-term effects of bariatric surgery in patients with NASH.

Methods: We performed a prospective study of 180 severely obese patients with biopsy-proven NASH, defined by the NASH clinical research network histologic scores. The patients underwent bariatric surgery at a single center in France and were followed for 5 years. We obtained liver samples from 125 of 169 patients (76%) having reached 1 year and 64 of 94 patients (68%) having reached 5 years after surgery. The primary endpoint was the resolution of NASH without worsening of fibrosis at 5 years. Secondary end points were improvement in fibrosis (reduction of ≥1 stage) at 5 years and regression of fibrosis and NASH at 1 and 5 years.

Results: At 5 years after bariatric surgery, NASH was resolved, without worsening fibrosis, in samples from 84% of patients (n = 64; 95% confidence interval, 73.1%-92.2%). Fibrosis decreased, compared with baseline, in samples from 70.2% of patients (95% CI, 56.6%-81.6%). Fibrosis disappeared from samples from 56% of all patients (95% CI, 42.4%-69.3%) and from samples from 45.5% of patients with baseline bridging fibrosis. Persistence of NASH was associated with no decrease in fibrosis and less weight loss (reduction in body mass index of 6.3 ± 4.1 kg/m2 in patients with persistent NASH vs reduction of 13.4 ± 7.4 kg/m2; P = .017 with resolution of NASH). Resolution of NASH was observed at 1 year after bariatric surgery in biopsies from 84% of patients, with no significant recurrence between 1 and 5 years (P = .17). Fibrosis began to decrease by 1 year after surgery and continued to decrease until 5 years (P < .001).

Conclusions: In a long-term follow-up of patients with NASH who underwent bariatric surgery, we observed resolution of NASH in liver samples from 84% of patients 5 years later. The reduction of fibrosis is progressive, beginning during the first year and continuing through 5 years.

Keywords: Gastric Banding; Gastric Bypass; Roux-en-Y-Gastric-Bypass; Sleeve Gastrectomy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Bariatric Surgery*
  • Biopsy
  • Female
  • Follow-Up Studies
  • France
  • Humans
  • Liver / pathology*
  • Liver Cirrhosis / etiology
  • Liver Cirrhosis / pathology*
  • Male
  • Middle Aged
  • Non-alcoholic Fatty Liver Disease / etiology
  • Non-alcoholic Fatty Liver Disease / pathology*
  • Obesity, Morbid / complications
  • Obesity, Morbid / diagnosis
  • Obesity, Morbid / surgery*
  • Prospective Studies
  • Remission Induction
  • Time Factors
  • Treatment Outcome
  • Weight Loss