The Severity of Ultrasonographic Findings in Nonalcoholic Fatty Liver Disease Reflects the Metabolic Syndrome and Visceral Fat Accumulation

TLDR

Nonalcoholic fatty liver disease is closely linked to the metabolic syndrome. The study aimed to assess how a new ultrasonographic scoring system correlates with metabolic syndrome, visceral fat, and fatty liver severity in healthy Japanese adults. Two hepatologists independently scored liver ultrasound images from 0 to 6, achieving high intra‑ and inter‑observer reliability (κ = 0.95), and the score’s predictive value was evaluated using ROC curves. The score achieved an AUC of 0.98 for NAFLD (sensitivity 91.7 %, specificity 100 %) and 0.82 for visceral obesity (sensitivity 68.3 %, specificity 95.1 %), with each one‑point increase raising the odds of metabolic syndrome by 1.37.

Abstract

Nonalcoholic fatty liver disease (NAFLD) is closely associated with the metabolic syndrome.We evaluated the association among the metabolic syndrome, visceral fat accumulation, and the severity of fatty liver with a new scoring system of ultrasonographic findings in apparently healthy Japanese adults.Subjects consisted of 94 patients who received liver biopsy and 4,826 participants who were selected from the general population. Two hepatologists scored the ultrasonographic findings from 0 to 6 points. We calculated Cohen's kappa of within-observer reliability and between-observer reliability. We evaluated the predictive value of the score by the area under a conventional receiver operating characteristic curve (AUC).Within-observer reliability was 0.95 (95% CI 0.93-0.97, P<0.001) and between-observer reliability was 0.95 (95% CI 0.93-0.97, P<0.001). The AUC to diagnose NAFLD was 0.980. The sensitivity was 91.7% (95% CI 87.0-95.1, P<0.001) and the specificity was 100% (95% CI 95.4-100.0, P<0.001). The AUC to diagnose visceral obesity was 0.821. The sensitivity was 68.3% (95% CI 51.9-81.9, P=0.028) and the specificity was 95.1% (95% CI 86.3-99.0, P<0.001). Adjusted odds ratio of the score for the metabolic syndrome was 1.37 (95% CI 1.26-1.49, P<0.001).The scoring system with abdominal ultrasonography could provide accurate information about hepatic steatosis, visceral obesity, and the metabolic syndrome in apparently healthy people who do not consume alcohol.