Despite the increasing prevalence of nonalcoholic fatty liver disease (NAFLD), its pathogenesis and clinical significance remain poorly defined.
Dr Hobbs and colleagues from Texas, America undertook a study in order to examine and compare the distribution of hepatic triglyceride content (HTGC) in 2,287 subjects.
The researchers took a multiethnic, population-based sample (32% white, 48% black, and 18% Hispanic) and used proton magnetic resonance spectroscopy to evaluate HTGC.
The research team noted that HTGC varied over a wide range (0.0%-42%; median, 4%) in the population.
Almost 1/3 of the population had hepatic steatosis, and most subjects with hepatic steatosis had normal levels of serum alanine aminotransferase (79%).
| Frequency of hepatic steatosis varied significantly with ethnicity: |
45% in Hispanics
33% in whites
24% in blacks
The researchers found that the frequency of hepatic steatosis varied significantly with ethnicity (45% in Hispanics; 33% in whites; 24% in blacks) and sex (42% in white men; 24% in white women).
In addition, the team observed that the higher prevalence of hepatic steatosis in Hispanics was due to the higher prevalence of obesity and insulin resistance in this ethnic group.
However, the researchers could not explain the lower frequency of hepatic steatosis in blacks by ethnic differences in body mass index, insulin resistance, ethanol ingestion, or medication use.
The research team found that the prevalence of hepatic steatosis was greater in men than women among whites, but not in blacks or Hispanics.
The ethnic differences in the frequency of hepatic steatosis in this study mirror those observed previously for NAFLD-related cirrhosis (Hispanics > whites > blacks).
Dr Hobbs concluded, "The significant ethnic and sex differences in the prevalence of hepatic steatosis documented in this study may have a profound impact on susceptibility to steatosis-related liver disease."