Carotid intima-media thickness is only weakly correlated with the extent and severity of XXXX .

@entity1 @entity453 @entity121 @entity6
BACKGROUND: @entity121 ( @entity121 ) of the common carotid artery (CCA), measured with external vascular ultrasound, has been widely used in clinical trials as a surrogate marker for @entity453 . Despite this, the degree of correlation between carotid @entity121 and the extent and severity of @entity453 ( @entity453 ) is not known. METHODS AND RESULTS: Common carotid @entity121 was measured by ultrasound in 350 consecutive subjects of age 60 +/- 10 years (range, 30 to 85 years) on the day of coronary angiography. Carotid mean @entity121 was 0.83 +/- 0.20 mm (range, 0.43 to 1.80 mm), and maximum @entity121 was 1.04 +/- 0.27 mm (range, 0.49 to 2.19 mm). Coronary angiograms were analyzed by independent observers for disease severity (number of vessels with > or = 70% stenosis), extent score, and a modified Gensini score. Mean carotid @entity121 was weakly but significantly correlated with @entity453 severity (r = .26), extent (r = .23), and modified Gensini score (r = .29, P < .0001 for all correlations). Carotid @entity121 was not clinically useful, however, because it was not specific or sensitive enough to identify @entity1 with or without significant @entity453 . Increasing age, male sex, and presence of @entity6 were all associated with a significantly (P < .01) higher @entity453 score than the average for any level of carotid @entity121 , suggesting differential effects of these traditional risk factors on the coronary and common carotid arteries. CONCLUSIONS: Although carotid @entity121 is significantly correlated with extent and severity of @entity453 , the relationship is weak. This relatively poor correlation (r2 < .10) should be considered in the interpretation of clinical trials that use carotid @entity121 as a surrogate end point for @entity453 .
