[Usefulness of comorbidity indices in operative gastric cancer cases].
OBJECTIVE
The purpose of the current study was to evaluate the usefulness of the following four comorbidity indices in gastric cancer patients who underwent surgery: Charlson Comorbidity Index (CCI), Cumulative Illness rating scale (CIRS), Index of Co-existent Disease (ICED), and Kaplan-Feinstein Scale (KFS).


METHODS
The study subjects were 614 adults who underwent surgery for gastric cancer at K hospital between 2005 and 2007. We examined the test-retest and inter-rater reliability of 4 comorbidity indices for 50 patients. Reliability was evaluated with Spearman rho coefficients for CCI and CIRS, while Kappa values were used for the ICED and KFS indices. Logistic regression was used to determine how these comorbidity indices affected unplanned readmission and death. Multiple regression was used for determining if the comorbidity indices affected length of stay and hospital costs.


RESULTS
The test-retest reliability of CCI and CIRS was substantial (Spearman rho=0.746 and 0.775, respectively), while for ICED and KFS was moderate (Kappa=0.476 and 0.504, respectively). The inter-rater reliability of the CCI, CIRS, and ICED was moderate (Spearman rho=0.580 and 0.668, and Kappa=0.433, respectively), but for KFS was fair (Kappa=0.383). According to the results from logistic regression, unplanned readmissions and deaths were not significantly different between the comorbidity index scores. But, according to the results from multiple linear regression, the CIRS group showed a significantly increased length of hospital stay (p<0.01). Additionally, CCI showed a significant association with increased hospital costs (p<0.01).


CONCLUSIONS
This study suggests that the CCI index may be useful in the estimation of comorbidities associated with hospital costs, while the CIRS index may be useful where estimatation of comorbiditie associated with the length of hospital stay are concerned.
Hwang
Se-Min
SM
Department of Preventive Medicine, College of Medicine, Korea University.
Yoon
Seok-Jun
SJ
Ahn
Hyeong-Sik
HS
An
Hyong-Gin
HG
Kim
Sang-Hoo
SH
Kyeong
Min-Ho
MH
Lee
Eun-Kyoung
EK
D000328:Adult; D000368:Aged; D015897:Comorbidity / Q000639:trends; D003627:Data Interpretation, Statistical; D005743:Gastrectomy; D006801:Humans; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D018709:Statistics, Nonparametric; D013270:Stomach / Q000473:pathology; D013274:Stomach Neoplasms / Q000453:epidemiology* / Q000401:mortality / Q000473:pathology / Q000601:surgery