NATURAL-HISTORY OF ABDOMINAL AORTIC-ANEURYSM WITH AND WITHOUT COEXISTING CHRONIC OBSTRUCTIVE PULMONARY-DISEASE

Purpose: To study the relation between abdominal aortic aneurysms and chronical obstructive pulmonary disease (COPD), in particular the sugg ested common elastin degradation caused by elastase and smoking. Metho ds: A cross-sectional population study and a prospective cohort study of small abdominal aortic aneurysms was performed in a community setti ng. All previous diagnoses recorded in a hospital computer database we re received for 4404 men 65 to 73 years of age who had been invited to a population screening for abdominal aortic aneurysm, One hundred for ty-one men had AAA (4.2%). They were asked to participate in an interv iew, a clinical examination, and collection of blood sample. Men with an abdominal aortic aneurysm 3 to 5 an in diameter were offered annual ultrasound scans to check for expansion. Results: Among patients with COPD 7.7% had abdominal aortic aneurysms (crude odds ratio = 2.05). T he adjusted odds ratio, however, was only 1.59 after adjustment for co existing diseases associated with abdominal aortic aneurysm (P = .13). The mean annual expansion was 2.74 mm per year among patients with CO PD, 2.72 among patients without COPD, and 4.7 mm among patients who us ed oral steroids compared with 2.6 among patients who did not use ster oids (P < .05). Concentration of serum elastin peptide and plasma elas tase-alpha(1)-antitrypsin complexes correlated negatively with forced expiratory volume in the first second (FEV1) among patients with COPD. However, multivariate regression analysis showed that concentration o f serum elastin peptide, therapy with beta-agonists, and FEV1 correlat ed positively with degree of expansion but that concentration of plasm a elastase-cll-antitrypsin complexes and serum alpha(1)-antitrypsin di d not influence expansion, suggesting that elastase plays an important role in the pathogenesis of COPD but not of abdominal aortic aneurysm . Conclusion: The high prevalence of abdominal aortic aneurysm among p atients with COPD is more Likely to be caused by medication and coexis ting diseases rather than a common pathway of pathogenesis.