Xiao X, et al. - In this retrospective analysis, researchers used the 2003-2014 Nationwide Inpatient Sample to assess the prevalence of atrial fibrillation (AF) in adult hospital encounters with end-stage COPD on home oxygen admitted for COPD exacerbation. They assessed the relation of AF to clinical factors, cost, length of stay, and hospital outcomes via multivariate-adjusted models. Of 1,345,270 included patients, AF was present in 18.2%. From 2003 to 2014, an increase in AF prevalence from 12.9% to 21.3% was noted. By age, sex, race, income, insurance type, and hospital region, variations were observed in AF prevalence. Factors related to increased odds of AF were advancing age, female sex, white race, high income, and large hospital size. The risk for in-hospital death, acute respiratory failure, invasive mechanical ventilation, noninvasive mechanical ventilation, acute kidney injury, sepsis, and stroke, was predicted by the presence of AF. Increased cost and length of stay were also reported in relation to AF.