S2445 Discordance Between Noninvasive Fibrosis Scores in MASLD: Clinical Predictors and Outcomes in a Veteran Population

Introduction: Noninvasive fibrosis scores, including Fib-4 and the NAFLD fibrosis score, are widely recommended for risk stratification in patients with metabolic dysfunction-associated steatotic liver disease (MASLD). However, the concordance between these 2 scores—and the clinical implications of discordance—remain poorly understood, particularly in cohorts with substantial heterogeneity. Understanding the prevalence, predictors, and outcomes of discordant results may inform more nuanced clinical decision-making, referral strategies, and patient management. We aimed to determine the frequency and clinical significance of discordance between Fib-4 and NAFLD fibrosis score in a MASLD cohort. Methods: We performed a retrospective analysis of 80 adults with MASLD seen at a veteran's affairs hospital. Discordance was defined as placement in different risk categories by Fib-4 and NAFLD fibrosis score using established cutoffs (Fib-4 >2.67; NAFLD FS >0.676). Multiple demographic and clinical features were compared between discordant and concordant groups. Multivariable logistic regression identified predictors of discordance. Clinical outcomes—including the prevalence of cirrhosis and MASH—were compared between groups. Results: Of 80 patients, 13 (15.8%) demonstrated discordance between Fib-4 and NAFLD fibrosis score. Discordant patients were significantly older (mean age 73 vs 58 years), more likely to have diabetes (83% vs 38%), had lower platelet counts (median 155 vs 239 × 10⁹/L), higher alanine aminotransferase (mean 44.8 vs 39.9 U/L), and much higher ASCVD 10-year risk (46.4% vs 12.0%) compared to concordant patients. Older age (OR per year: 1.13, 95% CI 1.04–1.23, P = 0.003) and T2DM (OR: 4.5, 95% CI 1.2–16.7, P = 0.024) were independently associated with discordance. The prevalence of cirrhosis or MASH higher in discordant patients (33.3%) compared to concordant patients (6.3%) (P = 0.009). Conclusion: Discordance between Fib-4 and NAFLD fibrosis score occurs in approximately 16% of MASLD patients and is strongly associated with older age, diabetes, lower platelet counts, and higher cardiovascular risk. Discordant patients experienced a greater than fivefold increased prevalence of cirrhosis or MASH compared to those with concordant scores, highlighting the clinical importance of recognizing and managing discordant findings. These results support the need for cautious interpretation of noninvasive fibrosis scores in high-risk populations. Prospective validation and investigation of optimal management strategies for discordant patients are warranted.