Distribution of Fibrosis‐4 index and vibration‐controlled transient elastography‐derived liver stiffness measurement for patients with metabolic dysfunction‐associated steatotic liver disease in health check‐up

Abstract Aims The multisociety consensus nomenclature has introduced steatotic liver disease (SLD) with diverse subclassifications, which are metabolic dysfunction‐associated steatotic liver disease (MASLD), metabolic dysfunction and alcohol‐associated steatotic liver disease (MetALD), alcohol‐associated liver disease (ALD), specific etiology, and cryptogenic. We investigated their prevalence, as per the new definition, in individuals undergoing health check‐ups. Additionally, we analyzed the distribution of Fibrosis‐4 (FIB‐4) index and vibration‐controlled transient elastography (VCTE)‐derived liver stiffness measurement (LSM) for MASLD. Methods In this cross‐sectional study, 6530 subjects undergoing a health check‐up in Japan were included. Conventional B‐mode ultrasound was carried out on all 6530 subjects, and those with MASLD underwent VCTE. Results The prevalence of SLD was 39.5%, comprising MASLD 28.7%, MetALD 8.6%, ALD 1.2%, specific etiology SLD 0.3%, and cryptogenic SLD 0.7%. Subjects with VCTE‐derived LSM ≥8 kPa constituted 2.1% of MASLD. FIB‐4 ≥1.3 showed that the sensitivity, specificity, positive predictive value (PPV), and negative predictive value for diagnosing VCTE‐derived LSM ≥8 kPa were 60.6%, 77.0%, 5.3%, and 98.9%, respectively. The referral rate to specialists was 23.8% using FIB‐4 ≥1.30. “FIB‐4 ≥1.3 in subjects <65 years and FIB‐4 ≥2.0 in subjects ≥65 years” showed higher PPV (6.7%) and lower referral rate (17.1%) compared with FIB‐4 ≥1.3, but the sensitivity (54.5%) did not show adequate diagnostic capability as a noninvasive test for diagnosing VCTE‐derived LSM ≥8 kPa. Conclusions Acknowledging the selection bias in hepatology centers, we undertook this prospective health check‐up study. Although the FIB‐4 index proves to be a convenient marker, it might not perform well as a primary screening tool for liver fibrosis in the general population (UMIN Clinical Trials Registry No. UMIN000035188).