Associations of age, gender and physical phenotypic dimension with serum liver enzyme levels among children and adolescents of Heilongjiang province

Objective To investigate the associations of age, gender and physical phenotypic dimensions, such as body mass index(BMI), waist circumference(WC), waist-to-height ratio(WhtR), with serum liver enzyme levels among children and adolescents of Heilongjiang province, and to provide scientific evidence for early health prevention and treatment among children and adolescents. Methods The overall samples were collected by multistage stratified random cluster sampling method from Jul.to Oct.in 2008 in Heilongjiang province.Height, weight and WC were measured, and the se-rum alanine aminotransferase(ALT), aspartate aminotransferase(AST) and gamma glutamine transfe-rase(GGT) levels were detected by using rate assay among 2 011 enrolled children and adolescents(902 males and 1 109 females; Han 1 177 cases, and Korean 834 cases) aged 10-18 years with complete data.The associations of BMI, WC and WhtR with serum liver enzyme levels were analyzed by Pearson linear correlation and multiple stepwise regression analysis. Results Among 10-18 years old children and adolescents of different gender, the serum LgALT(male r=0.100, P<0.05; female r=0.086, P<0.05)and LgGGT(male r=0.262, P<0.05 ; female r=0.072, P<0.05)were positively correlated with age, while serum LgAST(male r=-0.201, P<0.001; female r=-0.227, P<0.001)levels were negatively correlated with age.The gender difference in serum LgALT, LgAST and LgGGT existed for each age group among 11-18 years old children and adolescents, with male higher than female.In addition, the serum LgALT level in the Korean children and adolescents were higher than that in both sexes of Han nationality.The serum LgALT and LgGGT levels in overweight and obese children and adolescents were significantly higher than that in BMI normal group with the same gender for both sexes(P<0.01), and serum LgALT, LgAST and LgGGT levels in male obese children and adolescents were significantly higher than that in overweight group with the same gender(P<0.05). By the multiple regression analysis, among male children and adolescents, serum LgALT level was mainly effected by age, nationa-lity and WhtR, serum LgAST level was mainly effected by age, and serum LgGGT level was mainly influenced by age, BMI and WhtR; among female children and adolescents, serum LgALT level was mainly affected by nationality and WhtR, serum LgAST level was mainly influenced by age, WC and WhtR, and serum LgGGT level was mainly influenced by BMI. Conclusions There exist certain associations among age, gender, physical phenotypic dimension and nationa-lity with serum liver enzyme levels among children and adolescents, so more attention should be paid to monitor the serum liver enzyme levels among the overweight and obese children and adolescents.And scientific diet and more exercise are suggested so as to reduce the liver fat. Key words: Child; Adolescent; Alanine aminotransferase; Aspartate aminotransferase; Gamma glutamine transferase