The objectives of this study are to quantify and compare vascular function in men and women by measuring carotid atherosclerosis, endothelial dysfunction, and ankle-brachial index and then to determine the effect of age, race-ethnicity, cardiovascular risk factors, biological markers and hormonal markers on these vascular measures to determine gender-specific models. The aims of this project are to determine if middle-aged men and women at risk for stroke have differences in functional and structural vascular assessments, and to develop comprehensive vascular health profiles in men and women.