title: Should the augmentation index be normalized to heart rate?
abstract: Pulse wave analysis(PWA) is widely used to investigate systemic arterial stiffness. The augmentation index(AIx), the primary outcome derived from PWA, is influenced by the mean arterial pressure(MAP), age, gender and heart rate(HR). Gender- and age-specific reference values have been devised, and it is recommended that the MAP be used as a statistical covariate. The AIx is also commonly statistically adjusted to a HR of 75 b·min(-1); however, this approach may be physiologically and statistically inappropriate. First, there appears to be an important physiological chronic interaction between HR and arterial stiffness. Second, the method used to correct to HR assumes that the relationship with AIx is uniform across populations. A more appropriate practice may be to include HR as an independent predictor or covariate; this approach is particularly recommended for longitudinal studies, in which changes in HR may help to explain changes in arterial stiffness.
authors.affiliation: Massey University, School of Sport and Exercise.
authors.forename: Lee
authors.initials: L
authors.lastname: Stoner
authors.forename: James
authors.initials: J
authors.lastname: Faulkner
authors.forename: Andrew
authors.initials: A
authors.lastname: Lowe
authors.forename: Danielle
authors.initials: D
authors.lastname: M Lambrick
authors.forename: Joanna
authors.initials: J
authors.lastname: M Young
authors.forename: Richard
authors.initials: R
authors.lastname: Love
authors.forename: David
authors.initials: D
authors.lastname: S Rowlands
mesh_terms: D000818:Animals; D062186:Arterial Pressure / Q000502:physiology*; D001783:Blood Flow Velocity / Q000502:physiology*; D002318:Cardiovascular Diseases / Q000175:diagnosis*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D063177:Pulse Wave Analysis; D059289:Vascular Stiffness / Q000502:physiology