Prevalence of Elevated Alanine Aminotransferase by Diagnostic Criterion, Age, and Gender among Adolescents

Subnormal Serum Liver Enzyme Levels: A Review of Pathophysiology and Clinical Significance

Subnormal levels of liver enzymes, below the lower limit of normal on local laboratory reports, can be useful diagnostically. For instance, subnormal levels of aminotransferases can be observed in vitamin B6 deficiency and chronic kidney disease. Subnormal alkaline phosphatase levels may indicate the presence of hypophosphatasia, Wilson's disease, deficiencies of divalent ions, or malnutrition. Subnormal levels of gamma glutamyl transferase may be seen in cases of acute intrahepatic cholestasis, the use of certain medications, and in bone disease. Finally, subnormal levels of 5'-nucleotidase have been reported in lead poisoning and nonspherocytic hemolytic anemia. The aim of this review is to bring attention to the fact that subnormal levels of these enzymes should not be ignored as they may indicate pathological conditions and provide a means of early diagnosis.

Association between serum alanine and aspartate aminotransferase and blood pressure: a cross-sectional study of Chinese freshmen

Background

High blood pressure is a well-recognized risk factor for cardiovascular events, and the incidence of hypertension is increasing among young people. This study investigated the relationship between ALT and AST levels and hypertension among freshmen in China.

Methods

This cross-sectional study was conducted in the Anhui Province from September to November 2018. A total of 3114 freshmen underwent a physical examination including testing of biochemical indicators and a standardized questionnaire.

Results

The overall prevalence of elevated ALT and AST were 6.8% and 2.3% among freshmen. The mean ALT and AST levels were higher in males (22.59 ± 21.98 vs.12.62 ± 10.30 U/L; 23.55 ± 12.24 vs. 20.02 ± 5.75 U/L, respectively). The prevalence of hypertension was significantly higher in men (16.1%) than in women (1.9%). The mean values of BMI, SBP, DBP, TC, TG, and LDL-C were found to be increased with elevated levels of serum ALT and AST in the quartiles (P for trend < 0.05). After adjusting for covariates, the risk of hypertension was significantly higher in the highest ALT quartile than in the lowest quartile (OR (95% CI) of 1.681 (1.028, 2.751) in males; 2.802 (1.102, 7.124) in females). A strong linear relationship was found between serum ALT levels and the odds of hypertension after adjustment for potential confounders only in total population and females (P for trend < 0.05).

Conclusions

These findings suggest that ALT level is significantly associated with hypertension both in male and female freshmen.