Sudden cardiac arrest in patients with chronic obstructive pulmonary disease: trends and outcomes from the national inpatient sample

Background: The outcomes of patients with sudden cardiac arrest (SCA) and chronic obstructive pulmonary disease (COPD) are largely unknown. The purpose of this study was to assess mortality, trends, predictors, and outcomes in patients of SCA and COPD from a large inpatient administrative database. Methods: Data from the National Inpatient Sample (NIS) was used from January 2002 to December 2014. Patients were identified by applying relevant International Classification of Diseases, Ninth Revision, Clinical Modification codes. Propensity score matching was applied for adjustment of cofounders. Binomial multiple logistic regression analysis was used to assess for predictors of mortality. Results: In total 59,610 were identified with sudden cardiac arrest in which 13,195 (22.1%) patients had COPD. The mean age was 65.6 years. 37.8% were females. In the propensity match cohort, Mortality was 44.4% in patients with SCA without COPD when compared to 47.6% in SCA patients with COPD (p < 0.01). COPD was independently associated with higher mortality (OR, 1.121 [95% CI; 1.070-1.175] p < 0.01). Comorbidities like, diabetes mellitus and liver disease were associated with higher mortality. Female sex, racial and ethnic minorities were independent predictors for higher mortality. Conclusions: SCA in settings of COPD may have high mortality when compared to patients with SCA and no concomitant COPD. Further research delving into potential mechanisms for SCA in COPD patients is warranted.