Is chronic obstructive pulmonary disease associated with increased arterial stiffness?

Summary 

Objective

We hypothesize that airflow limitation is associated with increasing arterial stiffness and that having COPD increases a non-invasive measure of arterial stiffness – the aortic augmentation index (AIx) – independently of other CVD risk factors.

Methods

This population study is based on 3374 subjects from the Copenhagen City Heart Study; 494 had COPD. We used multiple linear regression analyses to examine the association between COPD and AIx adjusted for CVD risk factors. Furthermore, we analyzed the association between AIx and FEV₁, FVC and FEV₁/FVC in the entire population.

Results

AIx was higher in subjects with COPD than in subjects without: 25.7 vs. 21.0 (p < 0.001) in men and 33.6 vs. 29.4 (p < 0.001) in women. We found no increase in AIx with COPD adjusted for CVD risk factors: difference 0.63 (−0.26 to 1.52, p = 0.16). In sensitivity analyses in subjects younger than 60 years with exclusion of mild COPD from the analyses, COPD was associated with an increase in AIx in men only of 4.1 (0.88–7.22, p = 0.007). AIx had a curvilinear association with FEV₁ and FVC but no association with the FEV₁/FVC ratio.

Conclusion

AIx and COPD are only weakly associated. In the general population, this finding argues against increased arterial stiffness, as measured by AIx, being a complication of COPD.

Keywords: Arterial stiffness, Augmentation index, Chronic obstructive pulmonary disease, Epidemiology