Predictors of Mortality in Hospitalized Adults with Acute Exacerbation of Chronic Obstructive Pulmonary Disease. A Systematic Review and Meta-analysis

RATIONALE: There is a need to identify clinically meaningful predictors of mortality following hospitalized COPD exacerbation. OBJECTIVES: The aim of this study was to systematically review the literature to identify clinically important factors that predict mortality after hospitalization for acute exacerbation of chronic obstructive pulmonary disease (COPD). METHODS: Eligible studies considered adults admitted to hospital with COPD exacerbation. Two authors independently abstracted data. Odds ratios were then calculated by comparing the prevalence of each predictor in survivors versus nonsurvivors. For continuous variables, mean differences were pooled by the inverse of their variance, using a random effects model. MEASUREMENTS AND MAIN RESULTS: There were 37 studies included (189,772 study subjects) with risk of death ranging from 3.6% for studies considering short-term mortality, 31.0% for long-term mortality (up to 2 yr after hospitalization), and 29.0% for studies that considered solely intensive care unit (ICU)-admitted study subjects. Twelve prognostic factors (age, male sex, low body mass index, cardiac failure, chronic renal failure, confusion, long-term oxygen therapy, lower limb edema, Global Initiative for Chronic Lung Disease criteria stage 4, cor pulmonale, acidemia, and elevated plasma troponin level) were significantly associated with increased short-term mortality. Nine prognostic factors (age, low body mass index, cardiac failure, diabetes mellitus, ischemic heart disease, malignancy, FEV1, long-term oxygen therapy, and PaO2 on admission) were significantly associated with long-term mortality. Three factors (age, low Glasgow Coma Scale score, and pH) were significantly associated with increased risk of mortality in ICU-admitted study subjects. CONCLUSION: Different factors correlate with mortality from COPD exacerbation in the short term, long term, and after ICU admission. These parameters may be useful to develop tools for prediction of outcome in clinical practice.