Background & Aims
Previous studies have identified a substantial degree of agreement between the non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated steatotic liver disease (MASLD) populations, but the same notion may not apply to normal-weight patients with a lower cardiometabolic risk burden. This study aims to investigate the CMRF distributions between normal-weight and overweight/obese MASLD, the agreement between historical NAFLD and MASLD, and to compare the risk of liver-related events (LREs) and all-cause mortality in normal-weight versus overweight or obese MASLD.
Methods
This study included participants with steatotic liver disease (SLD) from five cohorts in Hong Kong, South Korea, and the United States. Participants were recruited from settings including both hospitals and communities. Individuals were classified into normal-weight and overweight/obese groups.
Results
This study included 33,793 participants with SLD from five cohorts, of whom 20,893 and 20,701 patients met the diagnosis of NAFLD and MASLD, respectively. Normal-weight patients with NAFLD demonstrated a lower CMRF distribution compared to those with overweight/obese NAFLD. In the community-based cohorts, the proportions of 0 CMRF ranged from 9.0-26.7% among normal-weight NAFLD, representing the discrepancy between MASLD and NAFLD definitions. Compared with the overweight/obese MASLD, the normal-weight MASLD had increased all-cause mortality (normal-weight vs. overweight/obese, 23.44 and 13.80 per 1000 person-years; p<0.001) but not LREs (2.81 and 2.59 per 1000 person-years; p=0.54) in the HK CDARS cohort.
Conclusions
Normal-weight individuals with NAFLD demonstrated a lower distribution of CMRFs, resulting in the incomplete agreement between historical NAFLD and MASLD.
Ethical Compliance
For all involved cohorts, the study protocols conformed to the ethical guidelines of the 1975 Declaration of Helsinki and were approved by the appropriate clinical research ethics committee and/or institutional review board, which provided either written consent or a waiver of informed consent.
