Impaired glucose tolerance, Type II diabetes mellitus and carotid atherosclerosis: prospective results from the Bruneck Study.
OBJECTIVE
Cardiovascular disease is a well-known severe complication of impaired glucose tolerance and Type II (non-insulin-dependent) diabetes mellitus. The independent contribution of glucose intolerance to cardiovascular disease and the underlying pathogenic mechanisms are still, however, not clear.


METHODS
In this prospective population-based study, 826 subjects aged 40-79 years underwent high resolution duplex ultrasound examinations of carotid arteries and extensive clinical and laboratory screenings for potential vascular risk factors at baseline and 5 years later. The ultrasound protocol involved measurements of maximum axial diameter of atherosclerotic plaques, if any, in common and internal carotid arteries on both sides and enable differentiation of two main stages in carotid artery disease, termed early non-stenotic and advanced stenotic atherosclerosis. Intima-media thickness was assessed at the follow-up examination.


RESULTS
Type II diabetes and, to a lesser extent, impaired glucose tolerance were found to be statistically significant risk predictors of 5-year changes in carotid atherosclerosis. These associations were in part independent of other vascular risk factors typically clustering with glucose intolerance. Both impaired glucose tolerance and Type II diabetes mellitus were not independently related to early non-stenotic atherosclerosis. In contrast, Type II diabetes mellitus was the strongest single risk predictor of advanced stenotic atherosclerosis [odds ratio 5.0 (95% confidence intervals 2.3-11.1)] and impaired glucose tolerance was of relevance as well [odds ratio 2.8 (1.2-6.4)] (p < 0.001).


CONCLUSIONS
Impaired glucose tolerance and, to a greater extent, Type II diabetes were strong independent predictors of advanced carotid atherosclerosis in our prospective population-based study.
Bonora
E
E
Department of Endocrinology and Metabolic Diseases, University of Verona Medical School, Italy.
Kiechl
S
S
Oberhollenzer
F
F
Egger
G
G
Bonadonna
R C
RC
Muggeo
M
M
Willeit
J
J
D000328:Adult; D000367:Age Factors; D000368:Aged; D001161:Arteriosclerosis / Q000000981:diagnostic imaging / Q000453:epidemiology*; D001824:Body Constitution; D002339:Carotid Arteries / Q000000981:diagnostic imaging; D016893:Carotid Stenosis / Q000000981:diagnostic imaging / Q000453:epidemiology*; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology*; D003925:Diabetic Angiopathies / Q000453:epidemiology*; D005260:Female; D018149:Glucose Intolerance / Q000453:epidemiology*; D006801:Humans; D007558:Italy; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012307:Risk Factors; D012737:Sex Factors; D014463:Ultrasonography
D008055:Lipids