Tuberc Respir Dis.  2016 Oct;79(4):289-294. 10.4046/trd.2016.79.4.289.

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

• Song SE
• Lee SH
• Jo EJ
• Eom JS
• Mok JH
• Kim MH
• Kim KU
• Lee MK
• Lee K

• KMID: 2365321
• DOI: http://doi.org/10.4046/trd.2016.79.4.289

Abstract

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.

Keyword

Intensive Care Units; Comorbidity; Respiration, Artificial; Prognosis

MeSH Terms

Comorbidity*
Humans
Intensive Care Units
Length of Stay
Male
Mortality
Prognosis
Proportional Hazards Models
Respiration, Artificial*
Retrospective Studies
Survivors
Tertiary Healthcare
Ventilators, Mechanical

Figure

• 

  Figure 1 The number of patients for each Charlson's weighted index of comorbidities (WIC) score (left Y axis) and the corresponding mortality (right Y axis).

• 

  Figure 2 Kaplan-Meier survival curves of 60-day mortality according to the number of Charlson' weighted index of comorbidities (WIC). ICU: intensive care unit.

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