Association of Metabolic Dysfunction-Associated Steatotic Liver Disease and Kidney Failure in the CKD Population

Introduction: Although fatty liver disease is a known risk factor for chronic kidney disease (CKD), its association with kidney failure remains unclear, especially after its redefinition as metabolic dysfunction-associated steatotic liver disease (MASLD). We aimed to quantify the association between MASLD and kidney failure in the CKD population by generating epidemiological data. Methods: We used 187,881 individuals with CKD from medical screening data of the National Health Insurance Service (NHIS) database of Korea. The population was categorized with no steatotic liver disease, MASLD, MASLD with increased alcohol intake, and alcoholic liver disease or steatotic liver disease with other specific etiologies. The risk of kidney failure was analyzed using Cox proportional hazard models adjusting demographic and clinical variables. Results: The study population had mean age of 63.3 years with 58% females. During the median of 9.28 (9.03-9.63) years of follow-up, 7497 (4%) events of kidney failure were identified. In the adjusted model, the "MASLD" group showed higher risk of kidney failure (hazard ratio [HR]: 1.146 [1.078- 1.219]) compared with "no steatotic liver disease." However, "MASLD with increased alcohol intake" ([HR 0.981 [0.834-1.154]) or "alcoholic liver disease or steatotic liver disease with other specific etiologies" (HR 1.098, [0.991-1.216]) showed nonsignificant difference. The association between MASLD and kidney failure was particularly accentuated in females (HR 1.301 [(1.192-1.420]), old age, nonhypertension, nonalbuminuria, and nonsmoking subgroup. Conclusion: In this large-scale observational study, MASLD was associated with kidney failure in individuals with CKD. Our findings highlight the importance of risk stratification in certain patients to prevent kidney failure.