Comparison of predictive value between two kinds of score system in hospital mortality of pneumonia patients

Abstract

Objective To compare the value in predicting hospital mortality of pneumonia patients between Charlson’s weighted index of comorbidities (WIC) and chronic health score (CHS), in Intensive Care Units (ICU). Methods The clinical data of pneumonia patients collected from September 2013 to September 2014 in ICU of two centers were retrospectively analyzed . The data included sex, age, comorbidites, past history about diseases contracted, presence or absence of severe sepsis. WIC and the acute physiology score (APS), age, chronic health evaluation Ⅱ(APACHEⅡ) score including CHS, APS, age scores, and sepsis related organ failure assessment (SOFA) were calculated. Results Of 293 patients, there are 195 (66.6%) males and 98 (33.4%) females; 197 (67.2%) survivors and 114(33.7%) non-survivors. The average age was (62.5±17.0) years. Compared with survivors, WIC scores were higher in non-survivors. However, the difference in CHS between two groups was not statistically significant. Along with the increase of WIC and CHS score, the patients mortality was increased. The univariate analysis showed that the variables including age, APACHEⅡ score, SOFA, APS, CHS, WIC, and presence or absence of severe sepsis, diabetes, stroke and congestive cardiac failure were related with patientss’ prognosis in 28 days. The univariate logistic regression of CHS (model 1) or WIC (model 2) combine with age, APS, presence or absence of severe sepsis and main comorbidities, such as diabetes, stroke and congestive cardiac failure indicated that risk of death depended significantly on age, APS, CHS, WIC, presence or absence of severe sepsis. The area under the receiver operating characteristics curve (ROC) in predicting mortality was 0.557 95%CI: (0.49-0.623)for CHS, it was lower than the 0.649 95%CI: (0.586-0.712)for WIC (P=0.206, Z=2.315). The AUC of multivariable equations was significantly better than that of APACHEⅡ score (P<0.01). Conclusions The WIC and CHS were independent risk factors for in-hospital mortality of pneumonia patients in ICU. WIC was better than CHS in evaluating comorbidity. Key words: WIC; CHS; APACHE Ⅱ; SOFA; Sepsis; Diabetes; Pneumonia; Outcome