Albuminuria and Metabolic Dysfunction-Associated Steatotic Liver Disease with Advanced Fibrosis in Primary Care

Metabolic dysfunction-associated steatotic liver disease (MASLD) and chronic kidney disease (CKD) are linked through the cardiovascular-kidney-metabolic (CKM) health spectrum. This study examines the association between albuminuria and advanced liver fibrosis, both prognostic risk factors for severe kidney and liver outcomes, in patients with MASLD.

This was a retrospective cross-sectional study of primary care patients with MASLD between 2012 and 2023. Urinary microalbumin-to-creatinine ratio (uACR) was the primary predictor variable and categorized as elevated (≥30 mg/g) or normal (<30 mg/g). The primary outcome was a fibrosis-4 index (FIB-4) at high risk for advanced fibrosis (≥2.67). Bivariate analyses described the cohort overall and by uACR status. Logistic regression models estimated the association of an elevated uACR with a FIB-4 at high risk for advanced fibrosis.

The sample included 463 patients of whom 45% had a uACR ≥30 mg/g and 9% had an FIB-4 ≥2.67. In the unadjusted logistic Firth regression model, uACR ≥30 mg/g was associated with an increased odds of having a high-risk FIB-4 (odds ratio [OR] 2.04; 95% confidence interval [CI] 1.06-3.90). After adjusting for estimated glomerular filtration rate (eGFR), there was no significant association between uACR ≥30 mg/g and a high-risk FIB-4 (OR: 1.73; 95% CI: 0.88-3.39). Using a predictor variable combining uACR and eGFR measures, the unadjusted (OR: 3.83; 95% CI: 1.77-8.25) and adjusted (OR: 2.87; 95% CI: 1.29-6.37) logistic Firth regression models demonstrated an association between ACR ≥30 mg/g and eGFR <59 mL/min with the outcome of a high-risk FIB-4.

Albuminuria and reduced eGFR were associated with measures of advanced fibrosis in primary care patients with MASLD, highlighting the link between CKD and MASLD along the CKM health spectrum.