To determine the long-term effects of bariatric surgery for patients with non-alcoholic steatohepatitis (NASH), sequential liver samples were evaluated that were collected at the time of bariatric surgery and 1 and 5 years later to assess the long-term effects of that surgery in patients with NASH.
A prospective study of 180 severely obese patients with biopsy-proven NASH defined by the NASH clinical research network histologic scores was performed. Patients underwent bariatric surgery at a single center in France and were followed for 5 years. Liver samples were obtained from 125 of 169 patients (76%), having reached 1 year in 64 of 94 patients (68%), having reached 5 years after surgery. The primary endpoint was resolution of NASH without worsening of fibrosis at 5 years. Secondary endpoints were improvement in fibrosis (reduction of 1 or greater stage at 5 years and regression of fibrosis and NASH at 1 and 5 years).
At 5 years after bariatric surgery, NASH was resolved without worsening fibrosis in samples from 84% of patients (N=64). Fibrosis decreased compared with baselines, in samples from 70.2% of patients. Fibrosis disappeared from samples from 56% of all patients and from samples from 45.5% of patients with baseline bridging fibrosis. Persistence of NASH was associated with no decrease in fibrosis unless weight loss (reduction in BMI of 6.3 kg/m² in patients with persistent NASH vs. reduction of 13.4 kg/m² 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. Fibrosis began to decrease from year 1 after surgery and continued to decrease until 5 years.
It was concluded in a long-term followup study of patients with NASH who underwent bariatric surgery, observation revealed resolution of NASH in liver samples from 84% of patients 5 years later. The reduction of fibrosis is progressive, beginning the first year and continuing through 5 years.
Lassailly, G., Caiazzo, R., NtandjaWandji, L. et al. “Bariatric Surgery Provides Long-Term Resolution of Nonalcoholic Steatohepatitis and Regression of Fibrosis.” Gastroenterology 2020; Vol. 159, pp. 1290-1301.