No association of chronic obstructive pulmonary disease with abdominal aortic aneurysm growth

Chronic obstructive pulmonary disease (COPD) is independently and positively associated with abdominal aortic aneurysm (AAA) presence. The aim of the present article was to determine whether COPD is associated with AAA growth. We reviewed currently available studies with a systematic literature search and meta-analytic estimate. Databases including MEDLINE and EMBASE were searched through July 2015 using Web-based search engines (PubMed and OVID). Studies considered for inclusion met the following criteria: the study population was AAA patients with and without COPD; and outcomes included data regarding AAA growth. For each study, growth rates in both the COPD and non-COPD groups were used to generate standardized mean differences (SMDs) and 95 % confidence intervals (CIs). Of 614 potentially relevant publications screened initially, we identified 10 eligible studies including data on a total of 2663 AAA patients. None of them demonstrated a statistically significant (positive or negative) association of COPD with AAA growth rates. A pooled analysis demonstrated that COPD is not associated with AAA growth rates (SMD, 0.04; 95 % CI, -0.07 to 0.15; p = 0.50). There was no evidence of significant publication bias. In conclusion, we found that COPD is not associated with AAA growth. Further investigations would be required to elucidate why COPD is not associated with AAA growth despite its positive association with AAA presence.