IMT was assessed with an ie33 ultrasound system (Philips, NL) using an 11 to 3 MHz linear array transducer. Experienced technologists blinded to participants' clinical data made all ultrasound measurements. The IMT was visualized bilaterally at the far wall of the CCA. In brief, a cursor representing the region of interest (10 mm) was positioned 1 cm in front of the beginning before the carotid bulb. Evaluation was performed using an automatic computerized system (Philips, NL Qlab software) and triggering was performed according to the Q wave of the ECG to enable measurement in complete relaxation of the ventricle. IMT was recorded 1 cm before the carotid bulb in a part without plaque on the left and right side. As mean IMT, the CCA was reported with the sum of IMT of the left and right side and afterwards divided by two. Plaques were defined as thickening of the IMT of at least 1.5 mm and presence was checked in all measured arteries. The number of plaques from both sides was recorded and subjects being classified as plaque positive when at least one plaque was measured on either side or plaque negative, when no plaque was recorded.
