Abstract
Ultrasound highresolution B-mode imaging was conducted on the carotid arteries of normal volunteers and dabetic patients to non-invasively determine the average thickness of the intimal and medial complex (avgIMC). In normal volunteers, avgIMC is 0.43±0.06mm (7-19 yr) and 0.87±0.09mm (50-59 yr), and does not exceed 1.1mm. The AvgIMCs of diabetics were significantly higher than those of normal volunteers over the all age groups. The avgIMC of diabetics with cerebral T2-prolonged regions, determined by MRI, was significantly higher than that of in diabetics without regions. Multivariate regression analysis on 566 NIDDMs showed age, hiht nonHDL-cholesterol, smolking, duration of diabetes, high systolic blood pressure and low HDL-cholesterol to be related to the progress of avgIMC. Similar study on 114 IDDMs aged 7-29 show both age and duration of diabetes to be related to the progression. Diabetics with averaged HbAlc>7.5% showed negligible change in avgIMC. Diabetics with averaged HbA1c>9.5% showed significantly higher change.
It is concluded that average thickness of intimal and medial complex of the carotid artery determined by ultrasound high resolution B-mode imaging is useful as a quantitative indicator of atherosclerosis. Aging and diabetes independently progress carotid atherosclerosis of adult NIDDM adult and young IDDM. Negligible change of avgIMC in diabetics with low HbA1c levels indicates that strict glycemic control could arrest carotid atherosclerosis in diabetics.
