The clinical significance of separate measurements of carotid arterial wall to assess the risk factor for atherosclerosis

Background: Carotid intima-media thickness (CIMT) is associated with several risk factors for atherosclerosis and has been consistently linked to cardiovascular and cerebrovascular disease. The clinical significance of separate measurements of CIMT, which is the sum of the intima (IT) and media thickness (MT), to use as an assessment of risk for atherosclerosis has not yet been fully established. Methods: Among 3377 patients who underwent B-mode ultrasound of carotid arteries and coronary angiography in the Medical Department of St. Mary’s Hospital from September 2003 to March 2009, 1146 subjects (M:F = 616:530; mean age, 57.7 ± 12.1 years) who were diagnosed with normal coronary arteries were enrolled in this study. IT, MT, and CIMT of the enrolled patients were manually measured using high-frequency ultrasonography (15 MHz linear array transducer). Results: In multivariate logistic regression analysis, age (β = 0.063, p < 0.0001), body mass index (BMI) (β = 0.028, p = 0.018), and hypertension (HTN) (β = 0.046, p = 0.0002) were associated with MT (R² = 0.256) and the IT/MT ratio (R² = 0.209). Age (β = 0.065, p < 0.0001), BMI (β = 0.025, p = 0.038), hemoglobin A1c (β = 0.045, p = 0.045), and HTN (β = 0.043, p = 0.0006) correlated with mean CIMT (R2 = 0.230). Age (β = -0.071, p < 0.0001) and BMI (β = -0.046, p = 0.002) were associated with the IT/MT ratio (R² = 0.219) on the left side. Age (β = 0.093, p < 0.0001) was related to MT (R² = 0.265) and mean CIMT (R² = 0.243) on the left side. Conclusion: We noted different atherosclerotic risk factors were related to measurements of the arterial wall in different ways. Therefore, separate measurements of CIMT might be a useful method to assess the risk for atherosclerosis.