Expected Pulse Wave Velocity and Vascular Age Calculation

To calculate the expected PWV in each child based on age, height, and MAP, we used the equation proposed by Reusz et al. (11) expressed as follows:

The expected PWV results were then compared with obtained PWV results (PWV difference) in each individual patient and subsequently compared between T1D and C groups.

To assess vascular age of our children, we combined normative age-based PWV data for children aged 7–18 years (11) obtained with applanation tonometry device (PulsePen) with normative age-based data for adults aged 19–40 years (21) obtained with two different devices (SphygmoCor and Complior) for PWV measurement using applanation tonometry for males and females separately. There was a significant linear relationship between chronological age (in years) and 50th percentile PWV (m/s) across the whole chronological age range from 7 to 40 years: PWV in males (m/s) = 3.99 + 0.08 × age (years), r² = 0.95, p <0.0001; PWV in females (m/s) = 4.01 + 0.08 × age (years), r² = 0.96, p < 0.0001. The expected age based on measured PWV (vascular age) for individual patients was then calculated as follows: patient's measured PWV – 3.99 for males (4.01 for females)/0.08. The intraindividual differences between the chronological age and the vascular age were then compared between groups.