Measurement of carotid IMT
Ultrasonography scans of the carotid artery were performed by expert, specifically-trained sonographers based on the Japan Society of Ultrasonics in Medicine guidelines [To avoid inter-reader variability, all scans were stored electronically and sent to the IMT evaluation committee. The sent images were inspected in random order by experienced investigators who were not informed of the clinical characteristics of the subjects, using automated digital edge detection software (Intimascope; MediaCross, Tokyo, Japan) [