BackgroundWeight loss improves fatty liver disease. No randomized trial has compared the effects of sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) on liver fat content and fibrosis.
ObjectiveTo compare the 1-year effects of SG and RYGB on hepatic steatosis and fibrosis.
DesignSingle-center, randomized, controlled trial (Oseberg [ObesitySurgery in Tønsberg]). (ClinicalTrials.gov: NCT01778738)
SettingTertiary care obesity center in Norway.
Participants100 patients (65% female; mean age, 47.5 years; mean body mass index, 42 kg/m2) with type 2 diabetes mellitus (T2DM).
InterventionFrom January 2013 to February 2018, patients were randomly assigned (1:1 ratio) to SG or RYGB.
MeasurementsThe primary outcome was remission of T2DM (previously published). Predefined secondary outcomes in the present study were hepatic steatosis and fibrosis assessed by magnetic resonance imaging (liver fat fraction), enhanced liver fibrosis (ELF) test, noninvasive indices, and liver enzymes.
ResultsLiver fat fraction declined similarly after SG (−19.7% [95% CI, −22.5% to −16.9%]) and RYGB (−21.5% [CI, −24.3% to −18.6%]) from surgery to 1-year follow-up, and almost all patients (SG, 94%; RYGB, 100%) had no or low-grade steatosis at 1 year. The ELF score category remained stable in 77% of patients, but 18% experienced worsening of fibrosis at 1 year, with no substantial between-group difference.
LimitationsSingle-center study, short follow-up time, and lack of power for secondary outcomes.
ConclusionWith an almost complete clearance of liver fat 1 year after surgery, RYGB and SG were both highly effective in reducing hepatic steatosis. Bariatric surgery had less influence on degree of fibrosis in the short term, but assessment of long-term progression is warranted.