Vascular Health in Childhood and Adolescence: Non-Invasive Assessment and Identification of Risk Factors

Abstract

Cardiovascular disease begins early in life; therefore, prevention efforts should start early, as interventions in early life may have the greatest long-term impact. This requires reliable pre-clinical measures of vascular health in childhood, yet current tools lack sensitivity and standardisation. This thesis aimed to identify age-appropriate non-invasive vascular measures, improve their collection and reporting, and apply them in early-life cohorts to explore potential risk or protective factors. Age-related changes in aortic and carotid intima-media thickness (aIMT, cIMT), carotid-femoral pulse wave velocity (cfPWV), and brachial and central blood pressure (BP) were assessed in individuals aged 2–20. aIMT increased strongly with age, while cIMT was more associated with male sex. cfPWV showed an age-related increase after age 9. Both central and brachial BP rose with age, but in children under 10.5 years, body size was not associated with BP. In adolescent females, BMI and fat mass were positively associated with central BP. These findings suggest aIMT is the most sensitive marker in early childhood, while cfPWV and BP measures are more informative in adolescence. Accordingly, we provided practical guidance to improve aIMT collection and reporting. aIMT was then applied in early-life cohorts, including the BABY1000 pilot birth cohort and an obesity prevention RCT in pre-school aged children. Neither study showed significant associations between aIMT and early growth, nutrition, or intervention effects. However, small sample sizes, influenced by the COVID-19 pandemic, limited the ability to test hypotheses robustly. Overall, age is a key consideration when selecting vascular health measures in children. While aIMT is feasible in early life, larger, well-powered studies are needed to assess the impact of early exposures and interventions on vascular outcomes.