Abstract 4136025: Establishing normal values for central systolic blood pressure and augmentation index in healthy young people

Background: The process of cardiovascular disease (CVD), a leading cause of death worldwide, commences in childhood. Increasing evidence indicates that early exposure to CVD risk factors in childhood is associated with impaired arterial distensibility and other vascular alterations, suggesting that vascular ageing biomarkers, that capture the deterioration in vascular structure and function, can be used to identify children at risk. However, the identification of early vascular alterations in the young is hampered by the lack of a recognized, vascular biomarker that can be used in clinical practice. The Youth Vascular Consortium, an international collaborative open resource has been established to answer these gaps by analysing different biomarkers, including central systolic blood pressure (cSBP) and augmentation index (AIx). These two non-invasive measures are related to CVD and end-organ damage, however, their assessment in clinical practice is limited by the lack of established normal values. Aims: We aimed to establish cSBP and AIx normal values in a young, healthy, international population. Methods: The Consortium collected data on 36,973 participants from 24 countries. We included 14,476 and 5,047 subjects respectively for the cSBP and AIx populations. Subjects were free of any CVD or cardiovascular risk factors. Data were collected from participants aged from 1 to 40 years. Normal values of cSBP and AIx were calculated as percentiles stratified by age and sex. Percentiles curves were generated using generalised additive models. Results: The cSBP percentile curves increase with the same trend for both males and females until age 13 years. Over this age, males experience greater cSBP than females. This is in contrast to AIx, which decreases with the same trend in both sexes until 15 years of age, after which females experience increased AIx. Conclusion: Normal values of cSBP and AIx in healthy young are now available according to age and sex with a wide geographical representation. Incorporating these values into clinical practice for young could facilitate their utilization as targets for the introduction and monitoring of interventions.