Correlation between Elevated Serum Alanine Aminotransferase and the Metabolic Syndrome

Objective To evaluate the correlativity of elevated serum alanine aminotransferases(ALT)to metabolic syndrome(MS)in Chinese.Methods Totally 351 subjects were divided as MS1,MS2 and MS3 groups according to the number of components of the MS,and normal glucose tolerance(NGT),impaired fasting glycaemia and impaired glucose tolerance(IFG/IGT)and type 2 diabetes mellitus(T2DM)groups according to the levels of serum glucose,respectively.The differences of ALT level and the aspartate amonotransferase(AST)/ALT ratio each group were investigated.And the relative risk of development of the MS due to the increase of ALT was estimated.Results The activity of ALT increased and AST/ALT ratio decreased with the progression of the MS from group MS1 to MS3(P0.01).There were statistically significant differences in ALT activity and AST/ALT ratio between MS3 and MS1(P0.01),while only in AST/ALT ratio between MS3 and MS2(P0.05).There was statistically significant difference in ALT activity among NGT,IGT/IFG and T2DM groups(P=0.01),AST/ALT ratio gradually decreased from group NGT to IGT/IFG and T2DM,but there was no significant difference(P0.05).ALT activity of the T2DM group significantly elevated as compared with the NGT group(P0.01).ALT activity and AST/ALT ratio were closely correlated with the index of insulin resistance(HOMA-IR),fasting true insulin concentration and the waist circumference(P0.01).The odd ratios(95% confidence interval)were 0.325(0.115-0.915),1.805(1.368-2.382),1.982(1.562-2.515)and 1.985(1.554-2.536)respectively in the four groups divided according to quartiles of ALT level,the subjects with higher ALT level had higher risk of development of the MS compared with those with lower ALT level.Conclusion Elevated activity of ALT are closely correlated with the occurrence and development of the MS.The ALT level near to the upper limit of normal range for the subjects with higher risk needs to be reviewed.The condition of MS progression should be correctly evaluated according to the ALT level combined with other indexes of MS.