Current, Former Smokers With COPD and Severe Emphysema May Have Larger Aorta Diameters

Patients with chronic obstructive pulmonary disease (COPD) and severe emphysema who were current or former smokers may have a larger aorta diameter compared with patients with COPD related to chronic bronchitis or bronchial wall thickening, according to study results published in the International Journal of Cardiology.

A team of US researchers analyzed aorta diameter measurements in 315 individuals (mean age, 68±7 years) with at least a 10 pack-year smoking history from the Multi-Ethnic Study of Atherosclerosis (MESA), the Emphysema and Cancer Action Project (EMCAP), and an outpatient community at Columbia University Medical Center. The study included 150 patients with COPD and 165 patients without COPD. In the COPD and non-COPD groups, the rates of emphysema were 56% and 19%, respectively.

COPD was defined by standard spirometric criteria, emphysema was measured quantitatively on computed tomography (CT), and bronchitis was ascertained from medical history. Further, emphysema-like lung was defined as the number of lung voxels with outside air corrected attenuation fewer than -950 Hounsfield units on chest CT.

Greater COPD severity was associated with increasing diameter of the ascending aorta, abdominal aorta, infrarenal aorta, and aortic arch (all P <.001). Patients classified in the most severe quartile of emphysematous change had the largest diameter at all 4 aorta locations vs patients in the least severe quartiles (all P <.001). The diameters of the aorta were significantly larger in patients with severe COPD compared with those without COPD in both the ascending and arch (both P <.001) and the abdominal aorta (P =.001).

Among patients with emphysema, those with COPD also had a significantly larger aorta diameter in the ascending (P =.003), arch (P =.002), and abdominal aorta (P =.04) compared with those without COPD.

Limitations of this study included its cross-sectional and observational nature as well as the limited age range (50-79 years) of the patients.

The investigators concluded that “[t]here may be similar elastolytic mechanisms destroying lung parenchyma to cause emphysema and weakening the aorta wall,” but validation of this hypothesis will “requires further investigation.”

Reference

Fujikura K, Albini A, Barr RG, et al. Aortic enlargement in chronic obstructive pulmonary disease (COPD) and emphysema: the Multi-Ethnic Study of Atherosclerosis (MESA) COPD study. Int J Cardiol. Published online February 12, 2021. doi:10.1016/j.ijcard.2021.02.017