The Prognostic Value of the Charlson's Comorbidity Index in Patients with Prolonged Acute Mechanical Ventilation: A Single Center Experience

BACKGROUND: The aim of our study was to evaluate the prognostic value of Charlson's weighted index of comorbidities (WIC) in patients with prolonged acute mechanical ventilation (PAMV, ventilator care ≥96 hours). METHODS: We retrospectively enrolled 299 Korean PAMV patients who were admitted in a medical intensive care unit (ICU) of a university-affiliated tertiary care hospital between 2008 and 2013. Survivors were defined as patients who survived for 60 days after ICU admission. RESULTS: The patients' mean age was 65.1±14.1 years and 70.6% were male. The mean ICU and hospital length of stay was 21.9±19.7 and 39.4±39.1 days, respectively. In addition, the 60-day mortality rate after ICU admission was 35.5%. The mean WIC was 2.3±1.8, with significant differences between nonsurvivors and survivors (2.7±2.1 vs. 2.1±1.7, p<0.05). The area under the curve of receiver-operating-characteristics curve for WIC was 0.593 (95% confidence interval [CI], 0.523–0.661; p<0.05). Based on Kaplan-Meier curves of 60-day survival, WIC ≥5 had statistically lower survival than WIC <5 (log-rank test, p<0.05). In a multivariate Cox proportional hazard model, WIC ≥5 was associated with poor prognosis (hazard ratio, 1.901; 95% CI, 1.140–3.171; p<0.05). The mortality rate of patients with WIC ≥5 was 54.2%. CONCLUSION: Our study showed a WIC score ≥5 might be helpful in predicting 60-day mortality in PAMV patients.