Several investigations as well as prospective studies have shown a significant
correlation between glucose metabolism and atherosclerosis in patients without
diabetes, but differences in parameters of glucose metabolism among the various
degrees of coronary disease in such patients have not been specifically evaluated.
To investigate glucose metabolism in patients with normal glucose tolerance
(NGT) and coronary heart disease (CHD).
Design, Setting, and Participants
Cross-sectional study of 234 men (mean [SD] age, 56.2 [6.1] years) with
NGT and suspected CHD who were admitted from January 1 through June 30, 2001,
to an academic medical center in Italy for coronary angiography.
Main Outcome Measures
Correlation of glucose metabolic factors and extent of atherosclerosis
determined by coronary angiography. Factors included levels of fasting and
postload glucose and insulin, glycosylated hemoglobin (HbA1c),
and lipids, as well as insulin resistance measured by homeostasis model assessment
Patients were divided into 4 groups based on coronary angiography: no
significant stenosis (n = 42), 1-vessel disease (n = 72), 2-vessel disease
(n = 64), and 3-vessel disease (n = 56). Simple correlation analysis showed
that the factors correlated with the extent of atherosclerosis were levels
of postload glucose (r = 0.667), HbA1c (r = 0.561), postload insulin (r =
0.221), and fasting insulin (r = 0.297), as well
as HOMA-IR (r = 0.278) (P<.001
for all). Multiple stepwise regression analysis suggested that the factors
independently associated with the number of stenosed coronary arteries were
levels of postload plasma glucose (r = 0.572), HbA1c (r = 0.413), postload insulin (r = 0.267), and fasting insulin (r = 0.174),
as well as HOMA-IR (r = 0.250) (P<.001 for all). Similar results were obtained after grouping patients
by Duke Myocardial Jeopardy Score.
For patients with NGT and different extents of atherosclerotic disease,
postload glycemia and HbA1c level are not equally distributed but
are significantly higher in those with more severe disease. This suggests
that the glycemic milieu correlates with the cardiovascular risk according
to a linear model.