Gender is a determinant of carotid artery stiffness independent of age and blood pressure

Objective: To identify the gender-specific differences in carotid artery structural and stiffening parameters by radiofrequency ultrasound (RFU) with an automatic arterial stiffness analyzing system. Methods: Seventy-two consecutive individuals (32 males and 40 females, age range from 36 to 62 years) with no history of significant cardiovascular diseases or carotid artery plaques were enrolled between September and December 2017. Quality intima-media thickness (QIMT) and quality arterial stiffness (QAS) parameters were automatically computed, including pulse wave velocity (PWV), vascular distension, compliance coefficient (CC), distensibility coefficient (DC), stiffness index alpha and beta, augmentation pressure (AP), and augmentation index (AIx). Those parameters were compared between males and females. Multiple linear regression analysis was performed to assess the independent association between gender and RFU parameters. Results: The mean age had no difference between males and females (47.8 +/- 3.3 vs 50.0 +/- 8.5 years, p = 0.19). Females had higher systolic blood pressure (134.53 +/- 9.65 vs 127.78 +/- 6.12 mm Hg) and diastolic blood pressure (85.83 +/- 3.94 vs 78.03 +/- 5.22 mm Hg), greater carotid QIMT (598.73 +/- 72.16 vs 550.84 +/- 29.37 mu m), advanced PWV (8.08 +/- 1.60 vs 6.24 +/- 0.70 m/s), higher stiffness index a (6.21 +/- 1.94 vs 3.95 +/- 0.78) and beta (9.43 +/- 3.17 vs 6.38 +/- 0.78), higher AP (6.68 +/- 2.24 vs 3.64 +/- 1.22 mm Hg) and AIx (7.42 +/- 2.08 vs 4.69 +/- 1.26%), all p < 0.001. Multiple linear regression analysis demonstrated gender was independently associated with carotid structural and elastic parameters. Conclusion: Gender independently impacts carotid structure and function, with females more vulnerable to the progression of arterial aging. Awareness of the gender differences on the risk stratification of carotid artery disease will benefit reliable assessments and specific management recommendations in clinical practice. Advances in knowledge: (1) RFU provides an mu m-unit quality IMT measurement and multiple quality arterial stiffness parameters. (2) Gender is an independent determinant in both the arterial structural and elastic aspects, with females of stiffer arteries in low CVD risk individuals.