Association Between Fatty Liver Index, Controlled Attenuation Parameter, and Metabolic Syndrome Stages: A Community-Based Study

Abstract

BACKGROUND Controlled attenuation parameter (CAP) is a recent ultrasound-based method for measuring hepatic steatosis, which is common in patients with metabolic syndrome (MetS). The fatty liver index (FLI), an algorithm-based method, is frequently used to evaluate hepatic steatosis. This study assessed how FLI and CAP relate to the earlier MetS stage and their ability to identify it. MATERIAL AND METHODS A total of 170 community-based individuals were studied. Demographic information, body mass index, waist circumference, and blood pressures were collected. CAP was assessed by FibroScan. Fasting glucose, lipid tests, and γ-glutamyl transferase were measured. The CAP and FLI results were categorized into quartiles, with the MetS stages as the main outcomes. The odds ratio (OR) of the outcomes was calculated using logistic regression. The area under the curve in receiver operating characteristic analysis (AUC-ROC) was used to detect the stages of MetS. Sensitivity, specificity, and appropriate cut-offs based on ROC analysis are shown. RESULTS The higher the FLI or CAP category, the lower the proportion of non-MetS and the higher the proportion of moderate MetS. Each single-quartile increase in FLI and CAP was associated with an increased likelihood of being in the higher MetS stages - FLI: adjusted OR 3.1 (2.23-4.32); CAP: adjusted OR 1.96 (1.48-2.59). In the ROC analysis, FLI had a higher AUC-ROC than CAP in separating the stages of MetS, although findings were significant (P<0.001). FLI in detecting the stages of mild-to-severe versus non-MetS performed well (AUC-ROC [95% confidence interval]: 0.79 [0.72-0.87]), with high sensitivity (0.86) but low specificity (0.62). CONCLUSIONS FLI and CAP were positively associated with the MetS stage and its components, suggesting that they could be used as a MetS screening tool in community studies.

Figure 1

Flowchart of participants included in this study.

Figure 2

The area under the receiver operating characteristic curve (AU-ROC) of FLI and CAP in predicting the outcome (A) mild-to-severe MetS vs non-MetS and (B) moderate-to-severe MetS vs mild-to-non-MetS. MetS – metabolic syndrome; FLI – fatty liver index; CAP – controlled attenuation parameter.