Metabolic correlates of nonalcoholic fatty liver in women and men.
Nonalcoholic hepatic steatosis associates with a clustering of metabolic risk factors and steatohepatitis. One risk factor for hepatic steatosis is obesity, but other factors likely play a role. We examined metabolic concomitants of hepatic steatosis in nonobese and obese men and women. Sixty-one obese women and 35 obese men were studied; both those with and without hepatic steatosis were compared against each other and against nonobese controls (17 women and 32 men) without hepatic steatosis. Obesity (defined as >or=25% body fat in men and >or=35% in women), was identified by x-ray absorptiometry, whereas hepatic steatosis (>or=5.5% liver fat) was detected by magnetic resonance spectroscopy. The primary endpoint was a difference in insulin sensitivity. Obese groups with and without steatosis had similar body fat percentages. Compared with obese women without hepatic steatosis, those with steatosis were more insulin resistant; the same was true for men, although differences were less striking. Obese subjects with hepatic steatosis had higher ratios of truncal-to-lower body fat and other indicators of adipose tissue dysfunction compared with obese subjects without steatosis.


CONCLUSIONS
These results support the concept that obesity predisposes to hepatic steatosis; but in addition, insulin resistance beyond that induced by obesity alone and a relatively high ratio of truncal-to-lower body fat usually combined with obesity to produce an elevated liver fat content.
Vega
Gloria Lena
GL
The Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9052, USA. Gloria.Vega@utsouthwestern.edu
Chandalia
Manisha
M
Szczepaniak
Lidia S
LS
Grundy
Scott M
SM
D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D000368:Aged; D050218:Body Fat Distribution; D005234:Fatty Liver / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D019906:Nuclear Magnetic Resonance, Biomolecular; D009765:Obesity / Q000150:complications*