Defining optimal fatty liver index thresholds for MASLD and MetALD using controlled attenuation parameter as...

Area of Science:

• Hepatology
• Diagnostic Biomarkers
• Metabolic Diseases

Background:

• Accurate diagnosis of metabolic dysfunction-associated steatotic liver disease (MASLD) is crucial.
• The fatty liver index (FLI) is a potential biomarker for steatotic liver disease (SLD), but optimal cutoffs for MASLD and MetALD are unclear.

Purpose of the Study:

• To determine the optimal cutoff values of the fatty liver index (FLI) for diagnosing MASLD and MetALD.
• To investigate potential sex differences in FLI diagnostic performance for these conditions.

Main Methods:

• A cross-sectional study of 2512 adults using abdominal ultrasonography (AUS) and vibration-controlled transient elastography (CAP).
• Control attenuation parameter (CAP) ≥ 268 dB/m was used as the cutoff for SLD diagnosis.
• Area under the receiver operating characteristic curve (AUROC) and Youden index were used to determine optimal FLI cutoff values.

Main Results:

• The study identified 956 individuals with SLD, including 648 with MASLD and 231 with MetALD.
• Optimal FLI cutoff values for MASLD were 26.7 overall, 26.9 for males, and 19.2 for females.
• Optimal FLI cutoff values for MetALD were 34.5 overall, 44.4 for males, and 30.8 for females, indicating higher cutoffs for MetALD and sex-specific differences.

Conclusions:

• The optimal FLI cutoff for MetALD is higher than for MASLD.
• Significant sex differences exist in the optimal FLI cutoffs for diagnosing both MASLD and MetALD.
• These findings refine the use of FLI for diagnosing liver conditions, considering sex-specific thresholds.