Background/aims: Increasing evidence suggests an association between elevated serum aminotransferase levels and metabolic disorders (metabolic syndrome, hyperlipidemia and diabetes mellitus). However, the significance of relatively low levels of aminotransferases in relation to metabolic disorders has not been fully investigated in the general population. We investigated the association between serum aminotransferase levels and metabolic disorders using data from a survey in Jilin Province, China.
Materials and methods: In 2007, a prospective survey was conducted throughout Jilin, China, covering both urban and rural areas. A total of 3835 people, 18-79 years old, were undergoing real-time ultrasonography, blood tests, and interviews with a structured questionnaire.
Results: Serum aminotransferase levels within the normal range were associated with metabolic syndrome independent of age, occupation, cultural and educational level, income, body mass index, waist circumference, smoking, and alcohol intake. Compared with the lowest level (< 20 IU/L), the adjusted odds ratios for alanine aminotransferase levels of 20-29, 30-39, 40-49, and >50 IU/L were 1.92, 2.50, 2.97, and 3.52 in men, and 1.38, 1.54, 3.06, and 2.62 in women, respectively. Near-normal serum aminotransferase levels associated with hyperlipidemia, non-alcoholic fatty liver disease, and diabetes mellitus were also found in the study.
Conclusions: Normal to near-normal serum aminotransferase levels are associated with metabolic disorders. Serum alanine aminotransferase levels of 21-25 IU/L for men and 17-22 IU/L for women are suggested as cut-off levels that detect metabolic disorders affecting the liver.