(HealthDay)—For patients with chronic obstructive pulmonary disease (COPD), computed tomographic (CT) measurement of pulmonary artery enlargement, as determined by a ratio of the diameter of the pulmonary artery to the diameter of the aorta (PA:A) of >1, correlates with severe exacerbations, according to a study published online Sept. 3 in the New England Journal of Medicine to coincide with presentation at the annual meeting of the European Respiratory Society, held from Sept. 1 to 5 in Vienna.
J. Michael Wells, M.D., from the University of Alabama at Birmingham, and colleagues conducted a multicenter observational trial involving former and current smokers with COPD to determine the association between a PA:A ratio of >1 and a history of severe exacerbations requiring hospitalization at the time of enrollment. The utility of the ratio was assessed as a predictor of events in longitudinal follow-up of this cohort and in an external validation cohort.
The researchers observed a significant association between a PA:A ratio of >1 and a history of severe exacerbations (odds ratio, 4.78). In both the trial cohort and the external validation cohort, a PA:A ratio of >1 correlated independently with an increased risk of future severe exacerbations (odds ratio, 3.44 and 2.80, respectively). PA:A ratio of >1 had the strongest association with severe exacerbations of all the variables analyzed.
"Pulmonary artery enlargement (a PA:A ratio of >1), as detected by CT, was associated with severe exacerbations of COPD," Wells and colleagues conclude.
Several authors disclosed financial relationships with pharmaceutical and biotechnology companies.
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