Prognosis of biopsy-confirmed MASLD: a sub-analysis of the CLIONE study.

BACKGROUND/AIMS: Metabolic dysfunction-associated steatotic liver disease (MASLD) was recently proposed as an alternative disease concept to nonalcoholic fatty liver disease (NAFLD). We aimed to investigate the prognosis in patients with biopsy-confirmed MASLD using data from a multicenter study.

METHODS: This is a sub-analysis of the CLIONE (Clinical Outcome Nonalcoholic Fatty Liver Disease) study, included 1,398 patients with NAFLD. Liver biopsy specimens were pathologically diagnosed, and histologically scored using the NASH Clinical Research Network system. Patients who met at least one cardiometabolic criterion were diagnosed with MASLD.

RESULTS: Approximately 99% of cases (n=1,381) were classified as MASLD. Patients without any cardiometabolic risk (n=17) had a significantly lower BMI than patients with MASLD (28.0 vs. 20.9 kg/m2, P<0.001), significantly lower levels of inflammation, ballooning, NAFLD activity score, and fibrosis stage in liver histology. These 17 patients had a median follow-up of 5.9 years, equivalent to 115 person-years, with no deaths, liver-related events, cardiovascular events, or extrahepatic cancers. The results showed that the prognosis for pure MASLD was similar with the original CLIONE cohort, with 47 deaths, and 1 patient underwent orthotopic liver transplantation. The leading cause of death was extrahepatic cancer (n =10). The leading causes of liver-related death were liver failure (n =9), hepatocellular carcinoma (n =8), and cholangiocellular carcinoma (n =4).

CONCLUSIONS: Approximately 99% of NAFLD cases corresponded to MASLD. NAFLD only group, which is not included in MASLD, had relatively mild histopathologic severity and a favorable prognosis. Consequently, the prognosis of MASLD was similar to that of NAFLD.