To determine mortality in patients with aortic abdominal aneurysm (AAA) and chronic obstructive pulmonary disease (COPD) as compared to patients with only AAA.
A retrospective cross-sectional study evaluated mortality for the four combinations of AAA (+ or -) and COPD (+ or -), using patient hospital records identified by ICD-9 codes. Other factors recorded and considered for predictive modeling included: coronary artery disease, peripheral arterial occlusive disease, hypertension, smoking, pulmonary function tests, hypercholesteremia, size and repair status of AAA.
Data were available for 460 subjects (455 males), with 115 subjects in each of four groups defined by the presence or absence of COPD and AAA. Mean ages (SD) were 75.12 (6.41), 76.49 (6.61), 77.70 (5.64), and 76.60 (5.92) for COPD-/AAA-, COPD+/AAA-, COPD-/AAA+, and COPD+/AAA+ groups, respectively (P=0.018, ANOVA, with only the oldest and youngest groups being significantly different, Tukey). Among these groups, mortality rates were 6.96, 66.96, 34.78, and 69.57 percent, respectively.Preliminary analysis, using logistic regression, found that COPD and AAA (P<0.0001) and their interaction (P=0.0002) were significant predictors of the binary mortality outcome. These effects were consistent when other factors were included in the model. The Table shows odds ratios for various grouping arrangements. The group-wise comparisons suggest that COPD had a significant effect on mortality in the absence (OR=27.10) or presence of AAA (OR=4.29), while AAA had a significant effect on mortality in the absence of COPD (OR=7.13) but not in its presence (OR=1.13).
Among patients positive for AAA, the risk of death is significantly greater when COPD is present. Among patients positive for COPD, the risk of death is not significantly raised by AAA. This outcome might due to a mortality ceiling effect observed for COPD but not for AAA.
Patients with AAA should be screened for COPD, because of the latter’s profound effect on mortality. Future studies on recognition and management of concurrent COPD and AAA seem warranted, with a potential to extend survival in this high-risk population.
Dmitry Lvovsky, None.