Cross-Sectional Study of Arterial Stiffness in Adolescents with Down Syndrome

Objectives To test whether youth with Down syndrome have aortic stiffness indices, as measured by pulse wave velocity (PWV), that differ from youth without Down syndrome and to compare reference-based age-adjusted (age-PWV-Z) and height-adjusted (Ht-PWV-Z) in youth with and without Down syndrome. Study design Cross-sectional study of PWV in 129 adolescents with Down syndrome and 97 youth of comparable age, sex, race/ethnicity, and body mass index (BMI). PWV, age-PWV-Z, and Ht-PWV-Z were compared. Regression models were developed to test for associations with PWV. Results Youth with Down syndrome and controls were comparable in BMI-Z (1.4 [−1.5 to 2.8] vs 1.2 [−2.0 to 2.8], P = .57) but not Ht-Z (−2.3 [−4.7 to 0.8] vs 0.4 [−2.0 to 2.6], P  Conclusions The lack of relationship of PWV, an independent predictor of adult cardiovascular events, with its traditional determinants including MAP suggests Down syndrome−specific phenomena may alter such relationships in this population. In youth with Down syndrome, Ht-adjusted PWV may overestimate aortic stiffness. Trial Registration Clinicaltrials.gov : NCT01821300 .