Prediction of mortality in patients undergoing maintenance hemodialysis by Charlson Comorbidity Index using ICD-10 database

Nephron Clin Pract. 2011;117(4):c379-84. doi: 10.1159/000321525. Epub 2010 Nov 12.

Abstract

Background/aims: Many patients with end-stage renal disease have additional comorbidities that are important to clinical study and impact the patient's outcome. The Charlson Comorbidity Index (CCI) is a popular tool and a strong predictor of outcome in end-stage renal disease patients. We obtained comorbidity data from the hospital discharge database using the International Classification of Disease, 10th revision (ICD-10) and analyzed the mortality rate in incident patients undergoing maintenance hemodialysis (HD).

Methods: We evaluated the medical records of a total of 456 patients on HD (58 ± 14 years of age, 56% males). We calculated CCI scores at the start of HD with information from the hospital discharge summary according to the ICD-10 code. We then analyzed patient mortality according to these CCI scores.

Results: The percentages of patients that had diabetes with end-organ damage (51.1%), congestive heart failure (9.9%), coronary artery disease (8.1%) and stroke (6.8%) were identified. CCI scores were 5.09 ± 2.01 (range 2-11). Four comorbidity groups were established by quartile ranking of the CCI scores: low, moderate, high and very high. The mortality rates were: 0.83, 7.70, 14.09 and 18.69 deaths/100 patient-years, respectively (p = 0.001). Compared with the low comorbidity group, the hazard ratios for mortality were 9.22 (95% CI 3.29-25.84) for the moderate group, 16.77 (95% CI 5.97-47.11) for the high group, and 22.37 (95% CI 8.08-61.93) for the very high group.

Conclusions: The CCI scores using the ICD-10 database information were significant predictors of mortality in incident patients undergoing maintenance HD.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Cardiovascular Diseases / classification
  • Cardiovascular Diseases / diagnosis
  • Cardiovascular Diseases / mortality
  • Comorbidity
  • Databases, Factual / standards*
  • Diabetes Mellitus / classification
  • Diabetes Mellitus / diagnosis
  • Diabetes Mellitus / mortality
  • Female
  • Follow-Up Studies
  • Humans
  • International Classification of Diseases / standards*
  • Kidney Failure, Chronic / classification
  • Kidney Failure, Chronic / diagnosis
  • Kidney Failure, Chronic / mortality*
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Renal Dialysis / mortality*
  • Retrospective Studies