Abstract Rationale There is a growing interest in the importance of cardiovascular (CVS)mortality in patients with chronic obstructive pulmonary disease (COPD). Epidemiological studies show that CVS mortality is the second leading cause of death in those with mild-to-moderate COPD after deaths from lung cancer. Studies also show that a reduced FEV1% is an independent risk factor for CVS mortality after adjustment for known CVS risk factors. Aim This study aimed to better understand the relative contribution of COPD GOLD 2-4 to dying of CVS disease in a high risk cohort of ever smokers. Methods In a secondary analysis from the National Lung Screening Trial (N = 18,463), where cause-specific mortality was a primary endpoint and adjudicated in 97% of all deaths, we compared known risk factors according to population attributable fraction (PAF). We also used Kaplan-Meier survival curves to compare the presence of comorbidities on CVS mortality relative to those with referent controls (no airflow limitation, no Pre-COPD, DM or CVS comorbidity). Results We found in our high risk older ever smokers (55-74 yrs, 30+ pack years and current smokers or quit15 yrs), that age and pack years made little contribution to dying of CVS causes in contrast to male gender (33%) current smoking (33%), CVS comorbidity (25%), GOLD 2-4 (20%), Pre-COPD (8%) and Diabetes mellitus (6%) all contributed to dying of CVS disease (p 0.05)(Figure 1). This suggests that GOLD 2-4 COPD and Pre-COPD combined (28%) are significant contributors to CVS death and collectively account for 4-fold more deaths than diabetes. Using Kaplan-Meier survival curves, we found those with diagnosed COPD or reporting DM, had overlapping CVS mortality (p = 0.089) which were both significantly greater than for referent controls. Conclusion After extensive adjustment for other risk variables, spirometric impairments, including GOLD 2-4 and Pre-COPD (GOLD 0 or PRISm), were significant contributors to CVS mortality. The PAF for dying a CVS death for GOLD 2-4 COPD (20%) was 3-fold that of diabetes (6%) and comparable to that for prior CVS history (25%), with overlapping Kaplan-Meier survival curves for COPD 2-4 and DM. This indicates that GOLD 2-4 airflow limitation is an independent marker of CVS-related death that should prompt primary prevention interventions. This abstract is funded by: None
Scott et al. (Fri,) studied this question.