Nearly one-third of the sample was found to have hepatic steatosis (defined as HTGC greater than 95th percentile of healthy persons, or 5.5 percent liver fat content) and "striking differences in the prevalence of hepatic steatosis were present among the three major ethnic groups," the authors report.
The prevalence of hepatic steatosis was significantly higher in Hispanics than in whites, and significantly lower in blacks than in whites. Furthermore, while the prevalence of hepatic steatosis was similar between the sexes in blacks and Hispanics, in whites, prevalence in men was twice as high than that in women. In all participants, HTGC correlated significantly with components of the metabolic syndrome. Notably, no significant positive correlation was found between daily ethanol intake and HTGC.
The results suggest that there are fundamental differences in lipid homeostasis among ethnic groups. The authors found that while blacks and Hispanics had similar levels of obesity and insulin resistance, blacks had a much lower prevalence of hepatic steatosis. They also found further evidence that a normal serum ALT level offers little diagnostic or prognostic value when assessing patients for NAFLD. Almost 80 percent of the subjects in this study with hepatic steatosis had normal serum ALT levels.
Limitations of this study include possible underestimation of alcohol intake, since this was self-reported by the patients in the study. Also, the researchers could not screen for infectious disease and therefore could not evaluate the impact of hepatitis C virus on hepatic steatosis.
In conclusion, the authors report, "Understanding the mechanisms responsible for the ethnic differences in the prevalence of hepatic steatosis and steatosis-related liver injury may provide
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