Arterial stiffness in childhood: A predictor for later cardiovascular disease?

Arterial stiffness is known as an important surrogate marker of vascular damage and a strong predictor of cardiovascular disease (CVD). Age-related degenerative changes in the intima of large elastic arteries contribute to the loss of arterial elastin and to increased arterial stiffness. Although arterial stiffness is strongly associated with ageing and is clinically shown mostly in older individuals, preclinical phases can occur in early childhood. Studies in children have shown a progressive increase in arterial stiffness by measuring the carotid intima-media thickness during childhood, indicating a structural alteration to the arterial wall starting already in early life. Other studies investigating arterial stiffness used different non-invasive functional measurements of arterial stiffness, such as pulse wave velocity (PWV) or ambulatory arterial stiffness index. As arterial stiffness directly increases blood pressure, systolic blood pressure (SBP) has also been used as an indirect measure of arterial stiffness. Several factors and diseases have been shown to contribute to arterial stiffening in adults. However, determinants of arterial stiffness at young age are not clear. Recently, height was identified as an important determinant of preschool arterial stiffness. Moreover, CVD risk factors such as hypertension, obesity, diabetes and metabolic syndrome have been previously shown to contribute to arterial stiffening in young people. Previous studies showed a higher arterial stiffness in patients with congenital heart disease (CHD). It has been hypothesized that patients with CHD have increased arterial stiffness already at an early age; and that this early vascular stiffening predisposes children to premature myocardial remodelling and cardiac damages later in life. Recently, Muller and colleagues from the Technical University of Munich presented a study investigating the frequency of arterial stiffness in children with CHD. They analysed central SBP as a measure of arterial stiffness in children aged 6–18 years with CHD (n1⁄4 417) and compared the results with an ageand gender-matched control group (n1⁄4 1466). This study revealed that children with CHD have significantly higher central SBP compared with the control group (102.1 10.2 vs. 100.4 8.6 mmHg, p-value< 0.001, respectively). The results also showed that among different subsets of children with CHD, central SBP was higher in subjects with left heart obstructions, transpositions of the great arteries after arterial switch, or with univentricular heart after total cavopulmonary connection, as compared with children in the control group. However, drawing firm conclusions from epidemiological studies assessing arterial stiffness in children with CHD is difficult, mainly due to the different methods applied. Some studies only assessed certain diagnostic subgroups, which makes comparison within various CHDs impossible. Using different devices and, more importantly, choosing between peripheral or central SBP may also result in different values and thereby different study results. The study performed by Muller and colleagues is a methodologically well-designed study and the contribution of this research study in childhood CVD preventive programme is timely. Control subjects were matched by age and gender, and the same methods were used to quantify arterial stiffness in children with and without CHD. This study used central SBP as a measure of arterial stiffness, which is considered a better predictor than peripheral SBP. The Mobil-oGraph device used in this study is a validated oscillometric measurement tool for non-invasive measurement of the central SBP, according to the British Hypertension Society and the European Society of Hypertension recommendations. Given that there is a strong positive association between hypertension and arterial stiffening, it seems logical to evaluate central SBP as a proxy of arterial stiffness in children. Nevertheless, it remains only a proxy and future studies