Insulin, proinsulin and insulin resistance status in relation to lipid profiles among school children in Taiwan-The Taipei Children Heart Study.
OBJECTIVE
Evidence suggests that there may be a metabolic syndrome characterized by hyperinsulinemia or insulin resistance associated with increased cardiovascular disease risk. The purpose of this study is to evaluate insulin, proinsulin or insulin resistance to determine which is the best parameter to predict lipid profiles among children in Taiwan.


METHODS
After multi-stage sampling, we randomly included 852 school children (415 boys and 437 girls) with a mean age of 13 yr in this study. We measured insulin and intact proinsulin levels by RIA (<0.2% cross-reactivity) and estimated insulin resistance index (IRI) using the homeostatic model assessment (HOMA) method. We used standard methods to measure atherosclerotic lipid profiles including total cholesterol (CHOL), triglyceride (TG), HDL-C, apolipoprotein A (ApoA), apolipoprotein B (ApoB), and lipoprotein[a] and calculated LDL-C and TCHR (total cholesterol to HDL-C ratio) levels.


RESULTS
Girls had higher CHOL, LDL-C, ApoA and ApoB levels than boys (p < 0.001). There was no significant difference in insulin, proinsulin and IRI status between boys and girls. Among boys, insulin, proinsulin and IRI were positively correlated with TG, ApoB and TCHR and negatively related to HDL-C. Among girls, these associations were attenuated and became insignificantly for TCHR and HDL-C. After adjusting for potential confounders, IRI and insulin were still positively associated with TG and ApoB levels and negatively associated with HDL-C in boys. However, in girls, proinsulin and insulin were positively associated with TG only. Finally, in the stepwise regression analyses, IRI was a better predictor of TG, HDL-C, and ApoB than insulin or proinsulin in boys. However, in girls, proinsulin was a stronger predictor than insulin or IRI for TG and TCHR.


CONCLUSIONS
From this study, we found that IRI (in boys) and proinsulin (in girls) levels are generally more significant and stronger parameters than insulin for predicting lipid profiles among children in Taiwan.
Hsieh
An-Tsz
AT
Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
Chu
Nain-Feng
NF
Shen
Mu-Han
MH
Wu
Der-Min
DM
Wang
Dan-Jiang
DJ
Hsieh
Shih-Ming
SM
D000293:Adolescent; D015992:Body Mass Index; D001835:Body Weight; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000209:etiology; D002648:Child; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood*; D007333:Insulin Resistance; D008055:Lipids / Q000097:blood*; D008297:Male; D011863:Radioimmunoassay; D012044:Regression Analysis; D012737:Sex Factors; D018709:Statistics, Nonparametric; D013624:Taiwan / Q000453:epidemiology; D014280:Triglycerides / Q000097:blood
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D007328:Insulin; D008055:Lipids; D014280:Triglycerides; D002784:Cholesterol