Objective: The Acute Physiology and Chronic Health Evaluation II (APACHE II) was developed to predict intensive-care unit (ICU) resource utilization. This study tested APACHE II's ability to predict long-term survival of patients with chronic obstructive pulmonary disease (COPD) admitted to general medical floors.
Design: We performed a retrospective cohort study of patients admitted for COPD exacerbation outside the ICU. APACHE II scores were calculated by chart review. Mortality was determined by the Social Security Death Index. We tested the association between APACHE II scores and long-term mortality with Cox regression and logistic regression.
Patients: The analysis included 92 patients admitted for COPD exacerbation in two Burlington, Vermont hospitals between January 1995 and June 1996.
Measurements and main results: In Cox regression, APACHE II score (hazard ratio [HR] 1.76 for each increase in a 3-level categorization, 95% confidence interval [CI] 1.16 to 2.65) and comorbidity (HR 2.58; 95% CI, 1.36 to 4.88) were associated with long-term mortality (P <.05) in the univariate analysis. After controlling for smoking history, comorbidity, and admission pCO2, APACHE II score was independently associated with long-term mortality (HR 2.19; 95% CI, 1.27 to 3.80). In univariate logistic regression, APACHE II score (odds ratio [OR] 2.31; 95% confidence internal [CI] 1.24 to 4.30) and admission pCO2 (OR 4.18; 95% CI, 1.15 to 15.21) were associated with death at 3 years. After controlling for smoking history, comorbidity, and admission pCO2, APACHE II score was independently associated with death at 3 years (OR 2.62; 95% CI, 1.12 to 6.16).
Conclusion: APACHE II score may be useful in predicting long-term mortality for COPD patients admitted outside the ICU.