Response to Wave Reflection in Systolic Hypertension: Smaller Stature, Shorter Aorta: Higher Pulse Pressure? and Questions Regarding the Aortic Measurements of Mitchell et al

TLDR: It is concluded that contributions of smaller diameter and increased wave reflection to increased pulse pressure may not be mutually exclusive and add that only properly conducted, longitudinal studies, not the analysis of an arbitrarily subdivided cross-sectional study, can inform a definite conclusion.

Abstract: We thank Richart et al1 and Roman and Devereux2 for their careful reading of our article3 and thoughtful feedback. Richart et al1 raise 3 points, described below. First, dichotomization of the sample at the overall median pulse pressure led to overrepresentation of women, who are shorter, in the high pulse pressure group. Wave reflection may have contributed substantially to higher pulse pressure in these shorter individuals. Second, in our Figure 3, women and men are pooled without any evidence that the slopes of the regression lines are the same in men and women. Third, peak wall tension seems to be higher in the proximal aorta in the high pulse pressure group and may have contributed to premature mechanical wear and consequent wall stiffening. They conclude that contributions of smaller diameter and increased wave reflection to increased pulse pressure may not be mutually exclusive and add that only properly conducted, longitudinal studies, not the analysis of an arbitrarily subdivided cross-sectional study, can inform a definite conclusion. Regarding dichotomization of the sample at the median pulse pressure, we wish to point out that the primary pulse pressure model, presented in our Table 3 and Figure 3, considered pulse pressure as a continuous variable. Furthermore, as noted in the article, the models …