Chronic liver disease is a major cause of morbidity and mortality in the United States.
Elevated aminotransferases are often used to detect liver disease, however, their prevalence and etiology are unknown.
In this study, researchers from Baltimore, Maryland, evaluated 15,676 adults (≥17 years) from the Third National Health and Nutrition Examination Survey.
The team considered participants to have elevated aminotransferase levels if either aspartate aminotransferase or alanine aminotransferase was above normal.
The researchers "explained" aminotransferase elevation if they found laboratory evidence of hepatitis B or C infection, iron overload, or if patients had a history of alcohol consumption.
They weighted analyses to provide national estimates.
|Aminotransferase elevation was unexplained in the 69%.|
|American Journal of Gastroenterology|
The team found that the prevalence of aminotransferase elevation in the United States was 8%.
Aminotransferase elevation was more common in men (9%), compared to women (7%). It was also more common in Mexican Americans (15%) and non-Hispanic blacks (8%), compared to non-Hispanic whites (7%).
The team were able to identify high alcohol consumption, hepatitis B or C infection, and high transferrin saturation in 31% of cases.
However, aminotransferase elevation was unexplained in the 69%.
The researchers found that in both sexes, unexplained aminotransferase elevation was associated with higher BMI, waist circumference, triglycerides, fasting insulin, and lower HDL. It was also associated with type 2 diabetes and hypertension in women.
Dr Jeanne Clark's team concluded, "Aminotransferase elevation was common in the United States, and the majority could not be unexplained by alcohol consumption, viral hepatitis or hemochromatosis".
"Unexplained aminotransferase elevation was strongly associated with adiposity and other features of the metabolic syndrome, and thus may represent nonalcoholic fatty liver disease".