Chronic Obstructive Pulmonary Disease and Risk of Sudden Cardiac Death

Objectives The purpose of this study was to determine whether chronic obstructive pulmonary disease (COPD) is associated with sudden cardiac death (SCD) in the community. Background COPD is linked to cardiovascular mortality; an association with SCD has not been systematically investigated in the general population. Methods In the Oregon Sudden Unexpected Death Study (approximately 1 million population), adult SCD case subjects were compared with geographic control subjects with coronary artery disease. Detailed clinical and electrocardiographic risk marker information was obtained from medical records. The association of COPD with SCD in the overall population and in a propensity score-matched dataset was assessed with logistic models. Results SCD case subjects (n = 728; age 69.9 ± 13.7 years) were more likely than control subjects (n = 548; age 67.2 ± 11.3 years) to have left ventricular ejection fraction ≤&35% (27.5% vs. 12.0%; p < 0.0001), COPD (30.8% vs. 12.8%, p < 0.0001), diabetes mellitus (47.7% vs. 31.8%; p < 0.0001), use short-acting beta-2 agonist agents (SBAs) (22.3% vs. 12.6%; p < 0.0001), and less likely to use beta-blockers (60.6% vs. 66.4%; p = 0.03). In multivariable analysis, COPD was significantly associated with SCD (odds ratio [OR]: 2.2; 95% confidence interval [CI]: 1.4 to 3.5; p < 0.001). There was no significant interaction between COPD and medications, but an interaction was identified between SBAs and beta-blockers (p = 0.04); SBAs were strongly associated with SCD in subjects not taking beta-blockers (OR: 3.3; 95% CI: 1.4 to 7.7; p = 0.005) but not in those taking beta-blockers (OR: 1.3; 95% CI: 0.7 to 2.3; p = 0.39). The COPD-SCD association was maintained in a propensity score-matched analysis. Conclusions COPD is associated with SCD risk in the community independent of medications, electrocardiographic risk markers, and left ventricular ejection fraction. Among other mechanisms, pro-arrhythmogenic right ventricular remodeling and systemic inflammation warrant further investigation.