Metabolic dysfunction-associated steatotic liver disease heterogeneity: Need of subtyping

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a widespread global disease with significant health burden. Unhealthy lifestyle, obesity, diabetes mellitus (DM), insulin resistance, and genetics have been implicated in the pathogenesis of MASLD. A significant degree of heterogeneity exists among each of above-mentioned risk factors. Heterogeneity of these risk factors translates into the heterogeneity of MASLD. On the other hand, MASLD can itself lead to insulin resistance and DM. Such heterogeneity makes it difficult to assess the natural course of an individual with MASLD in clinical practice. At present MASLD is considered as one disease despite the variability of etiopathogenic processes, and we lack the consensus definitions of unique subtypes of MASLD. In this review, pathogenic processes of MASLD are discussed and a need of subtyping is recommended.