Gender And Ethnic Differences In Arterial Aging Are Partly Accounted By Body Size And Blood Pressure

Purpose: Aging is associated with an overall increase in stiffness and the loss of compliance and distensibility of the arterial system. Gender and ethnic differences in arterial stiffness may be due to anthropometric differences between ethnic groups. Materials and Methods: We studied participants of the MESA (Multi-Ethnic Study of Atherosclerosis), an NHLBI sponsored study of individuals aged 45 to 84 years free of cardiovascular disease and including African, Hispanic, Chinese and White Americans. Local distensibility (distensibility coefficient; DC) and stiffness (Young’s modulus; YM) were measured in the right common carotid artery. Global large (LAE; C1) and small artery elasticity (SAE; C2) measures were derived from radial artery pressure waveforms. Anthropometric variables (height and weight) and age, gender, pulse pressure and mean blood pressure were used in multiple linear regression models to study their associations with measures of stiffness. Results: We studied 3207 women (mean age 62.0 ± 10.3 years) and 2937 men (mean age 62.2 ± 10.2 years). Ethnic differences were apparent in all measures of arterial compliance but decreased after adjustment for anthropometric measurements. Carotid artery DC and YM maintained ethnic differences with whites having less stiff arteries than other groups. Men had more compliant and less stiff vessels than women. Age was positively and consistently associated with arterial stiffening and loss of compliance while the importance of anthropometric measures varied. In women, multivariable models including anthropometric variables accounted for 36.2% of the variability of DC, 15.1% of YM, 26.5% of C1 and 28.6% of C2. Results were similar for men. Conclusion: Women have stiffer and less compliant arteries than men. Arterial distensibility and compliance decrease with age in all ethnic groups. Studies on global and local measures of arterial function should assess basic anthropometric factors in their analytical approaches. However, anthropometric measures do not completely account for observed differences in arterial aging among ethnic groups.