Determining the sensitivity and specificity of the calculated fatty liver index in comparison with ultrasound.

Background: Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease in human history and it is expected to surpass other causes of liver disease mortality by 2030. Therefore, finding an alternative way to diagnose steatosis in the early stage when imaging modalities are not available is crucial. This study decided to validate the optimal cut-off points and the sensitivity and specificity of the Fatty Liver Index (FLI) based on the Iranian population compared to ultrasonography.
Methods: The data of 367 individuals, 108 males and 259 females over 35, were analyzed. Hepatic steatosis was identified by ultrasound. FLI was determined from waist circumference, gamma-glutamyl transferase, triglyceride, and body mass index data. The receiver operating characteristic curve (ROC) was used to determine the best FLI index cut point for diagnosing nonalcoholic fatty liver. The sensitivity and specificity indices were calculated for the determined cut point.
Results: The AUC of the FLI index in diagnosing NAFLD in the total population was 0.733 (95% CI: 0.68-0.77, specificity = 0.6705, sensitivity = 0.7320) with the optimal COP of 40.6. There was a statistically significant association between non-alcoholic liver disease and FLI-based ultrasound (p < 0.0001). Furthermore, the sex-specific optimal COPs of FLI was 33.4, specificity = 0.6071, sensitivity = 0.8462 in men vs. 27.8, sensitivity = 0.8233, specificity = 0.7655 in women.
Conclusion: FLI is a reliable tool for identifying individuals with NAFLD. It has the potential to aid in detecting and managing this condition in large-scale populations while other methods are not available. We also determine an optimal COP of 40.6 with sensitivity and specificity of 73.20% and 67.05% in the general population, respectively.
Competing Interests: Declarations. Declarations: The results/data/figures in this manuscript have not been published elsewhere, nor are they under consideration by another publisher. While preparing this work, the author used ChatGPT to paraphrase some parts of the article. After using this tool, the author reviewed and edited the content as needed and took full responsibility for the publication’s content. Ethics approval and consent to participate: The study protocol was registered and approved by the Ethics Committee of Fasa University of Medical Sciences (FUMS) by No: IR.FUMS.REC.1400.095 Furthermore, the study was performed following the Declaration of Helsinki. Informed consent was obtained from all subjects and/or their legal guardian(s). Consent for publication: Not applicable. Competing interests: The authors declare no competing interests.
(© 2024. The Author(s).)