Vascular structure and function in women: relationship with body mass index

BACKGROUND: The purpose of the present study was to compare endothelial function in lean (body mass index [BMI]=18.0-24.9 kg/m2); overweight (BMI=25-29.9 kg/m2); and obese (BMI>30 kg/m2), healthy, eumenorrheic women. METHODS: Eighteen lean, 22 overweight, and 19 obese eumenorrheic middle-aged women were studied. Vascular structure and function were assessed via non-invasive ultrasound imaging of the carotid and brachial arteries. Body composition, blood pressure, fasting blood lipids, glucose, and insulin also were measured. RESULTS: The groups demonstrated significantly (p<0.001) different mean values for total body, lean body, and fat masses. The obese group demonstrated significantly (p<0.05) elevated fasting glucose and insulin levels and lower high-density lipoprotein levels as compared to the lean group. The overweight group also demonstrated elevated fasting glucose levels as compared to the lean group (p<0.05) with no significant difference from the obese group. Only systolic blood pressure differed among the three groups, being elevated in the obese group compared to the lean group (p<0.05). The obese group demonstrated significantly (p<0.05) elevated carotid artery lumen diameter, carotid artery wall cross-sectional area, and brachial artery lumen diameter with significantly (p<0.05) lower flow-mediated dilation as compared to the lean group. The overweight group demonstrated elevated carotid artery wall cross-sectional area and brachial artery lumen diameter as well as lower flow-mediated dilation as compared to the lean group (p<0.05). CONCLUSIONS: The results of this study support the hypothesis that carotid artery wall cross-sectional area is elevated and flow-mediated dilation reduced in overweight and obese eumennorheic women as compared to lean counterparts in relation to BMI classification.