P6.13 ADULT GUIDE-LINES ARE NOT APPLICABLE TO MEASURE PWV PATH LENGTH IN PAEDIATRICS

Abstract

Aortic pulse wave velocity (PWV) is a sensitive marker of arterial stiffness in children. In our previous study we have presented reference tables for PWV normal values in children. A recent consensus document provides arguments for the use of 80% of the direct carotid femoral distance as the most accurate distance estimate in adults. In the present work we aimed to assess if a transposition of the adult PWV measurement method is valid in childhood. Data of children participating to our previous work establishing age and height specific PWV normal values were re-evaluated. A total of 1008 healthy children (mean age:15.2 years, 495 males) were included in the study. We have recalculated PWV values using the subtractive method path length (L(SM)) and 80% of direct path length (L(0.8)). We have constructed Bland-Altman (BA) plots to assess the difference between PWV(SM) and PWV(0.8), and the distances L(SM) and L(0.8) in different age groups. The concordance between PWV(SM) and PWV(0.8) is excellent in children below 14 years (BA, ΔPWV mean:0.19 m/s, SD:0.40).However, in children >14 years, the difference increases (BA, ΔPWV mean:0.57 m/s, SD:0.36), and there is a proportional error between PWV(SM) and PWV(0.8) (BA, r:0.18; p<0.001), and in parallel there is also a proportional error between L(SM) and L(0.8) (BA, r:-0.24;p<0.001). The path length measurement suggested for adults may not be transponible to children throughout all age groups without reservation. Thus we propose to keep the current tables and values, unless the validity of a particular measurement is proved. (Grant: OTKA100909)