Resolution of Metabolic Dysfunction-associated Steatohepatitis With No Worsening of Fibrosis After Bariatric Surgery Improves 15-year Survival: A Prospective Cohort Study.

Background & Aims: The aim of this study was to investigate the consequences of the histological progression of metabolic dysfunction-associated steatohepatitis (MASH) and fibrosis on long-term survival after bariatric surgery.

Methods: From 1994 to 2021, 3028 patients at the University Hospital of Lille were prospectively included. Baseline liver biopsies were systematically performed with proposed follow-up biopsies 1 year after surgery, mainly in patients with MASH. We evaluated the association of the baseline and 1-year histologic progression of MASH and fibrosis status and long-term survival using Cox regression models.

Results: At baseline, 2641 patients (89%) had a biopsy, including 232 with MASH (8.7%) and 266 (10.8%) with significant fibrosis (grade F2-F4). The median follow-up was 10.1 years. At 1 year, 594 patients had qualitative paired biopsies. Survival was shorter at the 15-year follow-up in patients with baseline MASH, than in those without (hazard ratio [HR], 2.21; 95% confidence interval [CI], 1.38-3.53) and in F2 to F4 than in F0 to F1 (HR, 3.38; 95% CI, 2.24-5.10). At the 1-year landmark analysis, compared with patients without baseline MASH, mortality increased in those with persistent MASH and/or if fibrosis worsened (adjusted HR, 2.54; 95% CI, 1.06-6.10), but not if MASH resolved without the worsening of fibrosis (adjusted HR, 0.73; 95% CI, 0.28-1.87). Similarly, compared with patients without significant fibrosis at baseline, patients with persistent significant fibrosis had increased mortality (adjusted HR, 4.03; 95% CI, 1.86-8.72) but not if fibrosis improved from F2 to F4 to F0 to F1 (adjusted HR; 1.49; 95% CI, 0.52-4.24).

Conclusion: Histologic remission of MASH or significant fibrosis improves survival after bariatric surgery.