Bariatric surgery was found to induce non-alcoholic steatohepatitis (NASH) resolution without worsening fibrosis in patients with severe obesity, according to 5-year follow-up data from a prospective study published in Gastroenterology.
Little is known about the long-term effects of bariatric surgery for patients with NASH; therefore, the researchers evaluated sequential liver samples collected at the time of bariatric surgery and at 1 and 5 years later, to assess the long-term effects of bariatric surgery in 180 patients with severe obesity and biopsy-proven NASH. The patients underwent bariatric surgery at a single center in France.
At 5 years after bariatric surgery, the operative intervention resolved NASH in samples from 84% of patients (n=64; 95% CI, 73.1%-92.2%). Fibrosis decreased from baseline in samples from 70.2% of patients (95% CI, 56.6%-81.6%) and disappeared from samples from 56% of all patients (95% CI, 42.4%-69.3%). Fibrosis also disappeared in samples from 45.5% of patients with baseline bridging fibrosis.
The persistence of NASH was associated with no decrease in fibrosis and less weight loss. The reductions in body mass index for patients with persistent NASH (6.3 ± 4.1 kg/m2) were different for patients with NASH resolution (13.4 ± 7.4 kg/m2; P =.017).
NASH resolution was observed 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).
The length of the liver specimens used during this analysis could be considered a study limitation, according to the investigators, because a length of 2 to 3 cm is typically recommended. The study took a “conservative approach” to biopsies and required specimens at least 8 mm long, “which is longer than the minimal length proposed by expert guidelines,” the study authors said.
Nevertheless, “this prospective 5-year follow-up of obese NASH patients showed that the beneficial effects of bariatric surgery on the resolution of NASH were durable and led to a sustained reduction in fibrosis over 5 years,” they concluded.
Lassailly G, Caiazzo R, Ntandja-Wandji L-C, et al. Bariatric surgery provides long-term resolution of nonalcoholic steatohepatitis and regression of fibrosis. Gastroenterology. 2020;159(4):1290-1301. doi: 10.1053/j.gastro.2020.06.006