FLOW-MEDIATED DILATION IN 9-YEAR-OLD TO 11-YEAR-OLD CHILDREN - THE INFLUENCE OF INTRAUTERINE AND CHILDHOOD FACTORS

Background Early life factors, particularly size at birth, may influen ce later risk of cardiovascular disease, but a mechanism for this infl uence has nut been established. We have examined the relation between birth weight and endothelial function (a key event in atherosclerosis) in a population-based study of children, taking into account classic cardiovascular risk factors in childhood. Methods and Results We studi ed 333 British children aged 9 to 11 years in whom information on birt h weight, maternal factors, and risk factors (including blood pressure , lipid fractions, preload and postload glucose levels, smoking exposu re, and socioeconomic status) was available. A noninvasive ultrasound technique was used to assess the ability of the brachial artery to dil ate in response to increased blood flow (induced by forearm cuff occlu sion and release), an endothelium-dependent response. Birth weight sho wed a significant, graded, positive association with how-mediated dila tion (0.027 mm/kg; 95% CI, 0.003 to 0.051 mm/kg; P = .02). Childhood c ardiovascular risk factors (blood pressure, total and LDL cholesterol, and salivary cotinine level) showed no relation with flow-mediated di lation, but HDL cholesterol level was inversely related (-0.067 mm/mmo l; 95% CI, -0.021 to -0.113 mm/mmol; P = .005). The relation between b irth weight and flow-mediated dilation was not affected by adjustment for childhood body build, parity, cardiovascular risk factors, social class, or ethnicity. Conclusions Low birth weight is associated with i mpaired endothelial function in childhood, a key early event in athero genesis. Growth in utero may be associated with long-term changes in v ascular function that are manifest by the first decade of life and tha t may influence the long-term risk of cardiovascular disease.