Coronary artery disease, COPD exacerbation and inflammation

<b>Background:</b> Exacerbations are linked to cardiovascular risk in COPD: cardiovascular events occur more often during exacerbation¹ and in frequent exacerbators². Increased levels of inflammation could be implicated in this. <b>Aims:</b> To determine if frequent exacerbation (≥2/year) or markers of inflammation are linked to coronary artery disease (CAD) in COPD. <b>Methods:</b> 50 subjects from the London COPD Exacerbation Cohort underwent CT coronary angiogram (CTCA), CT thorax, spirometry, systemic inflammatory markers and sputum culture at baseline. Participants with obstructive CAD on CTCA (≥50% stenosis in ≥1 epicardial vessel) were compared to those with non-obstructive/no CAD (&lt;50% stenosis/no CAD). <b>Results:</b> Of those with obstructive CAD, 35% were frequent exacerbators. Of those without obstructive CAD, 59% were frequent exacerbators (P=0.1, chi-square test). Obstructive CAD was associated with increased plasma fibrinogen levels (3.7g/L versus 3.3g/L, P=0.02, unpaired t-test) and higher rates of sputum bacterial growth (≥2 cultures positive for same bacteria at baseline) (30% versus 7%; P=0.05, Fisher’s exact test). When correcting for age, sex, FEV1 and smoking, plasma fibrinogen (P=0.03, linear regression), CT evidence of bronchial wall thickening (P=0.05, logistic regression) and sputum bacterial growth (P=0.05, logistic regression) were associated with obstructive CAD. <b>Conclusions:</b> Obstructive CAD was not related to exacerbation frequency in patients with COPD, but was related to plasma fibrinogen, bronchial wall thickening and sputum bacteria, indicating a possible role for inflammation in the relationship between COPD and cardiovascular risk. 1. Kunisaki, K.M. et al. AJRCCM 2018;198(1):51-7 2. Donaldson, G.C. et al. Chest 2010;137(5):1091-7