Predictors of Hospital Admission for Chronic Obstructive Pulmonary Disease Exacerbations in Canadian Emergency Departments

OBJECTIVES: The objective was to examine predictors of hospital admission among adults presenting to Canadian emergency departments (EDs) for acute exacerbations of chronic obstructive pulmonary disease (COPD). Current acute treatment approaches and outcomes 2 weeks after the ED visit are also described. METHODS: Subjects, aged > or =35 years presenting with COPD exacerbations to 16 EDs across Canada, underwent a structured in-ED interview and a telephone interview 2 weeks later. RESULTS: Of 501 study patients, 247 (49.3%; 95% confidence interval [CI] = 44.9% to 53.6%) were admitted. Admitted patients were older, were more often former smokers, and had more admissions for COPD during the past 2 years. They also reported more days of activity limitation and use of inhaled beta(2)-agonists in the previous 24 hours. Canadian Triage and Acuity Scale (CTAS), respiratory rate (RR), and airflow obstruction were more severe in the hospitalized group. Most of the patients received inhaled beta(2)-agonists, anticholinergics, oral corticosteroids (CS), and antibiotics; hospitalized patients received more aggressive treatments. The median ED length of stay (LOS) of admitted patients was 13.1 hours (interquartile range [IQR] = 7.4-23.0) compared to 5.6 hours (IQR = 4.2-8.4) in discharged patients. Admission was associated with at least two COPD admissions in the past 2 years (odds ratio [OR] = 2.10; 95% CI = 1.24 to 3.56), receiving oral CS for COPD (OR = 1.72; 95% CI = 1.08 to 2.74), having a CTAS score of 1-2 (OR = 2.04; 95% CI = 1.33 to 3.12), and receiving adjunct ED treatments (OR = 3.95; 95% CI = 2.45 to 6.35). Use of EDs for usual COPD care was associated with a reduced risk of admission (OR = 0.43; 95% CI = 0.28 to 0.66). CONCLUSIONS: Exacerbations of COPD in Canadian EDs result in prolonged ED stays and approximately 50% hospitalization despite aggressive acute treatment approaches. Historical, severity, and treatment-related factors were strongly associated with hospital admission. Validation of these results should be completed prior to widespread use.