Introduction COPD is associated with increased cardiovascular events, independent of established risk factors. Arterial stiffness and carotid intima-media thickness (CIMT) are surrogates of cardiovascular risk and we sought to determine their relationship with COPD severity and prognosis in the ERICA (Evaluation of role of inflammation in airways disease) multi-site UK study: the largest cohort study focusing on cardiovascular manifestations in COPD.

Methods Spirometry, haemodynamic measures (aortic pulse wave velocity (aPWV), augmentation index (AIx), peripheral and central blood pressure (BP)) and CIMT (ultrasound measure of carotid artery intima-media layer thickness) were performed in 729 COPD subjects aged ≥40 years. COPD severity was classified by BODE Index [BMI, Obstruction (FEV1), Dyspnoea (mMRC score), Exercise tolerance (6-minute walk distance)], a validated score based on clinical variables and predictor of mortality in COPD.

Results Mean aPWV was 10.3 (SD 2.6) m/s, AIx 27 (10)%, brachial BP 144/82 (18/11) mmHg, central BP 131/82 (18/11) mmHg, CIMT 0.86 (0.4) mm.

BODE correlated with aPWV (p < 0.0001) and this was maintained when adjusted for study site, age, supine heart rate (HR) mean arterial pressure (MAP), years smoked and cardiovascular comorbidities (MI, stroke, diabetes, peripheral vascular disease), p < 0.0001. BODE was also associated with AIx when adjusted for site, age, seated HR and MAP, years smoked and cardiovascular comorbidities, p < 0.01. The constituent variables of BODE did not have the same significant association with both aPWV and AIx, Table 1.

An inverse correlation of BODE with central systolic BP (p = 0.003) was observed and this was maintained after adjustment for study site, age and HR p = 0.03. There was no significant relationship between BODE and CIMT.

Conclusions BODE is associated with arterial stiffness in COPD, independent of traditional risk factors. Its negative relationship with systolic pressure suggests increasing arterial stiffness with COPD severity, is independent of blood pressure. The BODE Index composite variables are not on the causal pathway for vascular stiffness, so its positive association likely reflects patient susceptibility to injury from smoke or other irritants in the lungs and vasculature. BODE may also enhance cardiovascular risk stratification in COPD, since its relationship with stiffness was independent of self-reported cardiovascular comorbidities.