Bariatric Surgery Provides Long-term Resolution of Nonalcoholic Steatohepatitis and Regression of Fibrosis.
Studies are needed to determine the long-term effects of bariatric surgery for patients with nonalcoholic steatohepatitis (NASH). We evaluated sequential liver biopsies, 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.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 biopsies 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 endpoints were improvement in fibrosis (reduction of ≥1 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 biopsies from 84% of patients (n=64; 95% CI, 73.1-92.2). Fibrosis decreased, compared with baseline, in biopsies from 70.2% of patients (95% CI, 56.6-81.6). Fibrosis disappeared from biopsies from 56% of all patients (95% CI, 42.4-69.3) and from biopsies 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 kg/m2±4.1 in patients with persistent NASH vs reduction of 13.4 kg/m2±7.4; 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