Epicardial Adipose Tissue in Patients with Chronic Obstructive Pulmonary Disease

RATIONALE Epicardial Adipose Tissue (EAT) volume as determined by chest computed tomography (CT) is an independent marker of cardiovascular events in the general population. COPD patients have an increased risk of cardiovascular disease, however nothing is known about the EAT volume in this population. OBJECTIVES To assess EAT volume in COPD and explore its association with clinical and physiological variables of disease severity. METHODS We measured EAT using low-dose CT in 171 stable COPD patients and 70 controls matched by age, smoking history and BMI. We determined blood pressure, cholesterol, glucose and HbA1c levels, microalbuminuria, lung function, BODE index, co-morbidity index and coronary artery calcium score (CAC). EAT volume were compared between groups. Uni and multivariate analyses explored the relationship between EAT volume and the COPD related variables. RESULTS COPD patients had a higher EAT volume [143.7 (P25-75, 108.3-196.6) vs 129.1 (P25-75, 91.3-170.8) cm(3), p = 0.02)] and the EAT volume was significantly associated with CAC (r = 0.38, p<0.001) and CRP (r = 0.32, p<0.001) but not with microalbuminuria (r = 0.12, p = 0.13). In COPD patients, EAT volume was associated with: age, pack-years, BMI, gender, FEV1%, 6 MWD, MMRC and HTN. Multivariate analysis showed that only pack-years (B = 0.6, 95% CI: 0.5-1.3), BMI (B = 7.8, 95% CI: 5.7-9.9) and 6 MWD (B = -0.2, 95% CI: -0.3--0.1), predicted EAT volume. CONCLUSIONS EAT volume is increased in COPD patients and is independently associated with smoking history, BMI and exercise capacity, all modifiable risk factors of future cardiovascular events. EAT volume could be a non-invasive marker of COPD patients at high risk for future cardiovascular events.