[Metabolic dysfunction-associated fatty liver disease, metabolic dysfunction-associated steatotic liver disease and clinically diagnosed osteoarthritis: a prospective cohort study].

Objective: We aimed to comprehensively assess the impact of metabolic dysfunction-associated fatty liver disease (MAFLD) and metabolic dysfunction-associated steatotic liver disease (MASLD) on the incidence of clinically diagnosed knee, hip, and hand osteoarthritis (OA). Methods: This prospective study analyzed data from 350 273 participants in the United Kingdom Biobank, with outcomes including all-cause OA, knee, hip, and hand OA, and polyarthrosis. Multivariable Cox proportional hazards regression models were used to estimate the association. Results: A total of 131 821 (37.6%) participants had MAFLD, and 102 110 (29.2%) had MASLD. MAFLD was associated with a higher risk of total OA (HR=1.72, 95%CI: 1.68-1.75). There are different OA risks among MAFLD subtypes: overweight and metabolic dysfunction subtypes increase the risk of total OA (HR=1.75, 95%CI: 1.71-1.79), whereas lean metabolism disorder subtypes are not associated with OA in any body part. MASLD (HR=1.57, 95%CI: 1.54-1.60) was associated with a higher risk of total OA, and the association became more prominent with increasing alcohol intakes. The effect of MAFLD on OA was consistent regardless of the presence of MASLD. Conclusions: MAFLD and MASLD are associated with an increased risk of OA, especially for knee OA. Obesity and alcohol intake play a key driving role in the association of steatotic liver disease with OA.