Abstract
Background and Objectives: Familial hypercholesterolemia (FH) is the most common genetic cause of cardiovascular disease. This study was aimed to examine the Achilles tendon thickness using plain radiograph of lateral heels in FH subjects (diagnosed using the Dutch Lipid Clinic Network [DLCN] score above 3 [possible, probable or definite FH]), non-FH subjects with elevated LDL-cholesterol (LDL-C) >130 mg/dL and subjects with LDL-C below 130 mg/dL. The sensitivity, specificity, and optimal cutoff values with the highest diagnostic accuracy for diagnosis of FH were determined. In addition, the coronary calcium score (CAC) and aortic valve calcium (AoVC) score using computed tomography were also investigated in FH and non-FH subjects. Results: Analysis was performed among 113 FH subjects, 58 non-FH subjects with high LDL-C and 55 subjects with LDL-C <130 mg/dL. The Achilles tendons in FH subjects were significantly thicker than those in the other 2 groups. Men had thicker Achilles tendons than women, but not significantly different. The cutoff thickness values ≥6.875 mm gave the highest diagnostic accuracy of 74% with 70% sensitivity and 78% specificity. For CAC scores among 112 FH subjects and 58 non-FH subjects, the proportion of FH subjects who had CAC >0 AU was not significantly different than that of non-FH subjects but the proportion of FH subjects who had AoVC > 0 AU was significantly higher that that of the non-FH subjects (10.7% vs. 1.7%, P= 0.029). CAC scores were significantly associated with age, LDL-C burden and Thai CV risk score Conclusions: Measurements of Achilles tendon thickness by plain radiographs in 133 FH subjects showed that cutoff values of ≥6.875 mm gave 74% accuracy with 70% sensitivity and 78% specificity. The proportion of FH subjects with CAC >0 was not significantly different than that of non-FH subjects but the proportion of FH subjects who had AoVC > 0 AU was significantly higher that that of the non-FH subjects.
