| Popis: |
Cardiovascular disease (CVD) is the leading cause of mortality among American women, and event rates are particularly high among African Americans. Recent technologies have facilitated early detection of subclinical vascular changes that precede clinical events. This research project examined the interrelationships of ethnicity, CVD risk factors, socioeconomic status (SES), and psychosocial health with these subclinical CVD changes among women. We examined data from the Study of Womens Health Across the Nation (SWAN) Heart Study (ns=303-536), a prospective epidemiological study of middle-aged African Americans and Caucasians. Coronary artery calcification (CAC), aortic calcification (AC), carotid artery intima-media thickness (IMT), and aortic pulse-wave velocity (PWV) were assessed at two visits, an average of 2.3 years apart. We examined ethnic differences in the associations of traditional CVD risk factors on PWV progression, or arterial stiffening. Systolic blood pressure (SBP) and waist circumference were associated with accelerated PWV progression. The effect of SBP was stronger among African Americans than among Caucasians, and LDL-C, diastolic blood pressure (DBP) and glucose levels were associated with PWV progression only among African Americans. African American women have poorer CVD outcomes but do not consistently have higher subclinical CVD in the literature. We speculated that SES partly explains relationships between ethnicity and subclinical CVD. Our findings indicated that low education was related to AC, after adjustment for ethnicity. African American ethnicity was associated with IMT and PWV after adjustment for education, but not income. A significant interaction between ethnicity and income suggested that low-income African American women were at greatest risk of presenting with high PWV. Finally, we observed that low educational attainment was associated with greater CAC progression among Caucasians but not African Americans. Financial strain partly mediated this relationship. Our findings suggest that certain CVD risk factors are more strongly related to progression among African Americans than among Caucasians. Furthermore, SES may explain some ethnic differences in the extent of subclinical CVD. Lastly, psychosocial indicators explain higher CAC progression among low-SES Caucasian women. This project has public health significance. Clarifying how biological and psychosocial factors contribute to subclinical CVD may reveal targets for prevention of clinical disease. |
