C-reactive protein is more strongly related to post-glucose load glucose than to fasting glucose in non-diabetic subjects; the Insulin Resistance Atherosclerosis Study.
OBJECTIVE
It has been suggested that cardiovascular disease may be more strongly related to post-challenge glycaemia than to fasting glucose concentrations. We hypothesized that subclinical inflammation, as indicated by elevated serum levels of C-reactive protein (CRP), may partially explain the association of cardiovascular disease with post-challenge glycaemia.


METHODS
We studied the relationship of CRP (measured with a highly sensitive immunoassay) with fasting glucose and 2-h glucose concentrations during an oral glucose tolerance test in non-diabetic subjects from the Insulin Resistance Atherosclerosis Study.


RESULTS
Spearman correlation analyses and multiple linear regression analyses showed a significant association of both fasting glucose and 2-h glucose concentrations with CRP levels, after adjusting for demographic covariates (age, sex, ethnicity, clinical centre; Spearman correlation coefficients: r = 0.18 for fasting glucose, r = 0.27 for 2-h glucose, both P < 0.0001). However, after additional adjustment for body mass index and waist-hip ratio only 2-h glucose (and not fasting glucose) was significantly related to CRP (r = 0.03 for fasting glucose, P = NS; r = 0.14 for 2-h glucose, P < 0.0001). Adding insulin sensitivity to the multivariate models further weakened the relationship of CRP to 2-h glucose (r = 0.07, P < 0.05). CRP mean values increased by 2-h glucose category (normal vs. impaired glucose tolerance vs. isolated post-challenge hyperglycaemia).


CONCLUSIONS
Chronic, subclinical inflammation, as indicated by elevated circulating CRP levels, is more strongly associated with post-challenge glycaemia than with fasting glucose levels in non-diabetic subjects. This association is partially independent of body fat and insulin resistance.
Festa
A
A
Department of Medicine, University of Texas Health Science Center at San Antonio, TX 78228-3900, USA.
D'Agostino
R
R
Tracy
R P
RP
Haffner
S M
SM
D000273:Adipose Tissue; D001161:Arteriosclerosis / Q000097:blood / Q000209:etiology*; D001786:Blood Glucose / Q000032:analysis; D002097:C-Reactive Protein / Q000378:metabolism*; D002908:Chronic Disease; D005215:Fasting / Q000097:blood; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D006943:Hyperglycemia / Q000150:complications*; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged
D001786:Blood Glucose; D002097:C-Reactive Protein