Masahito Michikura1,2, Masatsune Ogura1, Masahiro Yamamoto3, Masahiko Sekimoto3, Chizuru Fuke1, Mika Hori1, Koji Arai2, Shinji Kihara4, Kiminori Hosoda5, Koji Yanagi6, Mariko Harada-Shiba1. 1. Department of Molecular Innovation in Lipidology, National Cerebral and Cardiovascular Center Research Institute. 2. Department of Clinical Laboratory, National Cerebral and Cardiovascular Center Hospital. 3. Department of Central Clinical Laboratory, Kenporen Osaka Central Hospital. 4. Department of Metabolic Medicine, Graduate School of Medicine, Osaka University. 5. Department of Endocrinology and Metabolism, National Cerebral and Cardiovascular Center Hospital. 6. Department of Cardiovascular Medicine, Kenporen Osaka Central Hospital.
Abstract
BACKGROUND: Difficulty in detecting and measuring Achilles tendon (AT) xanthomas may be responsible for underdiagnosis of familial hypercholesterolemia (FH). We aimed to determine a cutoff value for AT thickness (AT-T) using ultrasonography to diagnose FH, and to investigate the relationship between AT-T and atherosclerosis.Methods and Results: Ultrasonographic AT-T and carotid intima-media thickness (IMT) were evaluated in 130 genetically diagnosed FH patients and 155 non-FH patients. The outline and internal properties of the AT could be clearly determined using ultrasonography, and a good correlation in AT-T was observed between ultrasonography and the conventional method of X-ray radiography (r=0.924, P<0.001). Cutoff values for the diagnosis of FH derived from receiver-operating curves were 5.8 mm (sensitivity 71%, specificity 78%) in men, and 5.5 mm (sensitivity 80%, specificity 81%) in women. Importantly, increased AT-T was positively associated with carotid IMT only in the FH group. Additionally, increased AT-T was associated with the presence of coronary artery disease in a logistic regression analysis adjusted for traditional cardiovascular risk factors. CONCLUSIONS: This is the first study to determine a cutoff value for AT-T based on ultrasonography for the diagnosis of FH in Japanese subjects. Clearer detection and easier measurement of AT-T using ultrasonography would encourage clinicians to diagnose FH more actively, and could solve the problem of underdiagnosis of FH.
BACKGROUND: Difficulty in detecting and measuring Achilles tendon (AT) xanthomas may be responsible for underdiagnosis of familial hypercholesterolemia (FH). We aimed to determine a cutoff value for AT thickness (AT-T) using ultrasonography to diagnose FH, and to investigate the relationship between AT-T and atherosclerosis.Methods and Results: Ultrasonographic AT-T and carotid intima-media thickness (IMT) were evaluated in 130 genetically diagnosed FHpatients and 155 non-FHpatients. The outline and internal properties of the AT could be clearly determined using ultrasonography, and a good correlation in AT-T was observed between ultrasonography and the conventional method of X-ray radiography (r=0.924, P<0.001). Cutoff values for the diagnosis of FH derived from receiver-operating curves were 5.8 mm (sensitivity 71%, specificity 78%) in men, and 5.5 mm (sensitivity 80%, specificity 81%) in women. Importantly, increased AT-T was positively associated with carotid IMT only in the FH group. Additionally, increased AT-T was associated with the presence of coronary artery disease in a logistic regression analysis adjusted for traditional cardiovascular risk factors. CONCLUSIONS: This is the first study to determine a cutoff value for AT-T based on ultrasonography for the diagnosis of FH in Japanese subjects. Clearer detection and easier measurement of AT-T using ultrasonography would encourage clinicians to diagnose FH more actively, and could solve the problem of underdiagnosis of FH.