Relationship between airflow obstruction and coronary atherosclerosis in asymptomatic individuals: evaluation by coronary CT angiography.

Airflow obstruction is associated with increased cardiovascular morbidity and mortality. However, the causal mechanisms linking airflow obstruction with higher incidence of cardiovascular events remain elusive. We evaluated the relationship between airflow obstruction, a key feature of chronic obstructive pulmonary disease (COPD), and prevalence, extent, and severity of coronary atherosclerosis in a large cohort of asymptomatic subjects. Participants were recruited from those undergoing spirometry and coronary computed tomography angiography (CCTA) as part of a general health evaluation from March 2009 to February 2011. Subjects were required to be over 40 years of age with no known CAD. Airflow obstruction was defined as forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) < 70%. Obstructive CAD, as measured by CCTA, was defined as maximum intra-luminal stenosis ≥ 50%. Participants with airflow obstruction or normal lung function were compared in terms of obstructive CAD prevalence, the extent and severity of coronary atherosclerosis; including coronary artery calcium score (CACS), atheroma burden score (ABS), atheroma burden obstructive score (ABOS), segment involvement score (SIS), and segment stenosis score (SSS). A total of 1888 subjects were eligible for study inclusion. Compared with participants with normal lung function, those exhibiting airflow obstruction were more likely to have obstructive CAD (p = 0.002). Airflow obstruction was associated with higher CACS (p = 0.043), ABS (p = 0.002), ABOS (p = 0.017), SIS (p = 0.003), and SSS (p = 0.002). Multivariable analyses adjusted for conventional cardiovascular risk factors revealed that airflow obstruction was independently associated with presence of CAD (odds ratio 1.673, confidence intervals [CI] 1.002-2.789, p = 0.048). In this asymptomatic population, the presence of airflow obstruction was associated with a greater prevalence, extent, and severity of coronary atherosclerosis and was seen to be an independent predictor of the presence of CAD.