Validation of the Charlson comorbidity index in patients undergoing revision total hip arthroplasty
Jan Schmolders1, Max J Friedrich, Robert Michel
1Department for Orthopaedic und Trauma Surgery, Rheinische Friedrich-Wilhelms-University Bonn, Sigmund-Freud-Strasse 25, 53105, Bonn, Germany, Jan.Schmolders@ukb.uni-bonn.de.
Insights
The Charlson comorbidity index (CCI) and age-related CCI predict complications in revision total hip arthroplasty (RTHA). These indices do not impact implant survival in the short to mid-term.
Area of Science:
- Orthopedic Surgery
- Comorbidity Assessment
- Health Services Research
Background:
- The Charlson Comorbidity Index (CCI) quantifies comorbidity impact on survival.
- The age-related CCI incorporates age as a risk factor.
- Limited data exists on CCI and age-related CCI in revision total hip arthroplasty (RTHA).
Purpose of the Study:
- To validate the influence of CCI and age-related CCI in RTHA patients.
- To assess impact on complication rates, resource use, implant survival, and mortality.
- To understand the predictive value of comorbidity indices in RTHA.
Main Methods:
- Retrospective study of 142 consecutive RTHA patients (Oct 2007-Nov 2012).
- Collected and analyzed routine clinical data, including complications, hospital stay, ICU needs, and mortality.
- Kaplan-Meier survivorship analysis for implant survival.
Main Results:
- CCI and age-related CCI significantly predicted postoperative complications and internal medical complications.
- Both indices influenced the need for surgical revision and dislocation rates.
- No significant influence of CCI or age-related CCI on implant survival was observed.
- Age-related CCI significantly impacted ICU stay and total hospital length.
Conclusions:
- CCI and age-related CCI are strong predictors of complication rates in RTHA.
- These indices are valuable for risk stratification in revision hip arthroplasty.
- Short- to mid-term implant survival is not influenced by CCI or age-related CCI.
Purpose:
The Charlson comorbidity index (CCI) was developed to quantify the influence of comorbidities on survival. The age-related CCI respects patients' age as an additional risk factor. There are several studies available based on administrative data regarding functional outcome, implant survival, resource use and length of hospital stay in patients undergoing primary total hip arthroplasty (THA). To date, there is a lack of knowledge regarding the correlation of the CCI and the age-related CCI in case of revision total hip arthroplasty (RTHA).
Objective:
Our objective was to validate the influence of the CCI and age-related CCI in patients undergoing RTHA regarding complication rate, resource use implant survival and mortality rate.
Methods:
Between October 2007 and November 2012, 142 consecutive patients undergoing RTHA were included in this retrospective study. Routine clinical data were collected and analysed as anonymized aggregated data. In accordance to CCI and age-related CCI the rate of complications (internal medical and surgical complications), the length of hospital stay and the need for ICU treatment and the mortality rate was evaluated. Kaplan-Meier survivorship was used to determine implant survival.
Results:
Twenty-one patients (15%) had a low risk CCI, 59 patients (41%) a moderate risk CCI and 62 patients (44%) a high risk CCI. The mean follow-up was 27 months (range 24-70 months). In total, we recorded 57 complications (40%), of which 45 were surgical (79%) and 12 were internal medical complications (21%). Twenty-four patients (17%) had to undergo revision surgery. CCI and age-related CCI had no influence regarding implant survival. We recorded a significant influence of the age-related CCI in regard to the necessity of postoperative intensive care unit stay and the length of total hospital stay. Further we recorded a significant influence of the CCI and the age-related CCI regarding postoperative complications and internal complications, postoperative dislocation and the need for surgical revision.
Conclusion:
In summary, we conclude that the CCI and the age-related CCI are strong predictors regarding complication rate in patients undergoing RTHA. In a short- to mid-term follow-up, no influence on implant survival is detectable.
