Serum aminotransferases, such as aspartate aminotransferase and alanine aminotransferase, is commonly used as an indicator of liver disease.
Dr Ray Kim and colleagues from Minnesota, USA determined the degree to which aminotransferase results are associated with increased mortality at the population level.
All adult residents of Olmsted County, Minnesota, who had a health care encounter at Mayo Clinic, Rochester, in 1995 were identified.
The research team extracted the patients' aspartate aminotransferase and alanine aminotransferase results from a laboratory database.
|13% had results greater than the upper limit of normal |
These subjects were followed forward from 1995 to 2006 and their survival was determined.
To exclude patients with abnormal results because of a terminal illness, deaths within the first 2 years were excluded.
The team's main outcome measure was survival.
Standardized mortality ratios were calculated, based on Minnesota White death rates.
During 1995, aspartate aminotransferase was measured at least once in 18,401 community residents.
Of these, 13% had results greater than the upper limit of normal.
Of 6,823 subjects who had their alanine aminotransferase results measured, 13% had results higher than the upper limit of normal.
Abnormal aspartate aminotransferase was associated with a significantly increased standardized mortality ratio.
The team noted that the standardized mortality ratio was also higher for abnormal alanine aminotransferase results.
In contrast, normal aspartate aminotransferase and alanine aminotransferase results was associated with a risk of death lower than expected.
Dr Kim's team concludes, "Serum levels of aspartate aminotransferase and alanine aminotransferase results obtained in a routine medical care setting are associated with future mortality in community residents."