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Arterial stiffness by pulse wave velocity in COPD: reliability and reproducibility

To the Editor: 

Cardiovascular diseases are the most common cause of mortality in chronic obstructive pulmonary disease (COPD) [1]. Arterial stiffness certainly plays a role in the increased cardiovascular risk of these patients [2, 3]. Arterial pulse wave velocity (PWV) constitutes a useful and safe non-invasive method [4] for assessing central arterial stiffness. The carotid-femoral PWV is considered as the gold standard method by the European Society of Hypertension/European Society of Cardiology [5] and is a strong predictor of future cardiovascular events and all-cause mortality, supporting its implementation into clinical research and daily practice [6]. In patients with COPD, feasibility and validity of this marker of arterial stiffness have been confirmed [2] and PWV is now used in studies evaluating cardiovascular risk and/or the efficacy of new bronchodilators and rehabilitation programmes [3, 7, 8]. However, little is known about its variability and reproducibility studies are lacking in the COPD population.

Here we report on the variability of PWV measurements between baseline, day 15 and day 42 in stable COPD patients. The carotid-femoral PWV was assessed using the Complior device (Alam Medical, Vincennes, France) and pulmonary function, blood pressure, metabolic and inflammatory markers were systematically measured at each evaluation. Pearson or Spearman correlation coefficients and intraclass correlation coefficient (ICC) allowed comparison of PWV at day 0 versus day …