Background: The association of the severity of hepatic steatosis in metabolic dysfunction-associated fatty liver disease (MAFLD)/metabolic dysfunction-associated steatotic liver disease (MASLD) and the remission of MAFLD/MASLD with CKD occurrence is unclear.
Methods and results: The study enrolled 79 540 participants from the Kailuan cohort. Hepatic steatosis was diagnosed by ultrasound. MAFLD/MASLD was defined as hepatic steatosis combined with metabolic dysfunction and MASLD further excluded alcohol or other causes of liver disease. Chronic kidney disease (CKD) was defined as estimated glomerular filtration rate<60 mL/min per 1.73 m2 or positive proteinuria (≥1+). Hazard ratio (HR) was calculated by Cox regression models. After a median follow-up of 12.9 years, CKD occurred in 20 465 participants. After adjusting for potential confounders, MAFLD was associated with a higher risk of CKD compared with non-MAFLD (HR, 1.12 [95% CI, 1.09-1.16]), and this risk increased with increasing severity of hepatic steatosis (P-trend<0.001). Consistent findings were observed when MASLD was used as the exposure. Compared with persistent non-MAFLD, no statistical difference was found in the risk of CKD in MAFLD remission (HR, 1.04 [95% CI, 0.95-1.15]); however, MASLD remission still had a higher risk of CKD compared with persistent non-MASLD (HR, 1.15 [95% CI, 1.03-1.27]). When grouped according to the prior severity of hepatic steatosis, there was no statistically significant difference in risk of CKD in mild-MAFLD/MASLD remission compared with persistent non-MAFLD/MASLD, but moderated/severe-MAFLD/MASLD remission still had a higher risk.
Conclusions: The risk of CKD in patients with MAFLD/MASLD increased with the severity of hepatic steatosis. Even after remission of the disease, patients with MAFLD/MASLD with prior moderate to severe hepatic steatosis still had a higher risk of CKD.
Keywords: chronic kidney disease (CKD); metabolic dysfunction–associated fatty liver disease (MAFLD); metabolic dysfunction–associated steatotic liver disease (MASLD); severity of hepatic steatosis.