Trends in Prevalence and Outcomes of Cannabis Use Among Chronic Obstructive Pulmonary Disease Hospitalizations: A Nationwide Population-Based Study 2005-2014

Background: Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of mortality in the United States. Due to the ongoing legalization of cannabis, its acceptance, availability, and use in the in-patient population are on the rise. In this retrospective study, we investigated the association of cannabis use with important outcomes in COPD hospitalizations. Methods: The National Inpatient Sample (NIS) data were analyzed from 2005 to 2014. The primary outcome of interest was the trends and outcomes of cannabis use among COPD hospitalizations, including in-hospital mortality, pneumonia, sepsis, and respiratory failure. Results: We identified 6,073,862 hospitalizations, 18 years of age or older, with COPD using hospital discharge codes. Of these, 6,049,316 (99.6%) were without cannabis use, and 24,546 (0.4%) were admitted with cannabis use. The majority of COPD hospitalizations with cannabis use were aged 50-64 (60%). Cannabis use was associated with lower odds of in-hospital mortality (odds ratio [OR] 0.624 [95% confidence interval (CI) 0.407-0.958]; p=0.0309) and pneumonia (OR 0.882 [95% CI 0.806-0.964]; p=0.0059) among COPD hospitalizations. Cannabis use also had lower odds of sepsis (OR 0.749 [95% CI 0.523-1.071]; p=0.1127) and acute respiratory failure (OR 0.995 [95% CI 0.877-1.13]; p=0.9411), but it was not statistically significant. Conclusions: Among hospitalized patients with a diagnosis of COPD, cannabis users had statistically significant lower odds of in-hospital mortality and pneumonia compared to noncannabis users. The association between cannabis use and these favorable outcomes deserves further study to understand the interaction between cannabis use and COPD