Impact of low birth weight and cardiovascular risk factors on endothelial function in early adult life

Background-Low birth weight is related to increased risk of coronary heart disease in adults and recently has been associated with vascular endothelia l dysfunction in children. We investigated whether the relation between bir th weight and endothelial function was still present in early adult life an d whether there was an interaction with emerging risk factors. Methods and Results-In 315 adults (165 women, 150 men, aged 20 to 28 years) , high-resolution ultrasound was used to determine endothelium-dependent an d -independent vascular responses of the brachial artery. Vascular measures were related to classic risk factors (smoking history, lipid profile, bloo d pressure, fasting insulin, exercise capacity, body mass index. and combin ed risk score) and birth weight. Low birth weight was associated with reduc ed flow-mediated dilation (coefficient=0.18 kg(-1), 95% CI 0.004 to 0.35, P =0.04) but not with endothelium-independent dilation. The difference in flo w-mediated dilation between the top and bottom fifths of birth weight was t he same as between smokers and nonsmokers. Increasing levels of acquired ri sk factors overwhelmed the association, and there was a significant interac tion of risk score with the birth weight-endothelial function relation (coe fficient of interaction term [birth weightXrisk score] = -0.12, 95% CI -0.2 2 to -0.03, P=0.01). Conclusions-Low birth weight is associated with endothelial dysfunction in young adults. This is most marked in individuals with lower risk factor pro files and may be relevant to the pathogenesis of atherosclerosis in later l ife.