Back to Journals » Clinical Epidemiology » Volume 11

Charlson Comorbidity Index Based On Hospital Episode Statistics Performs Adequately In Predicting Mortality, But Its Discriminative Ability Diminishes Over Time

Authors Pylväläinen J, Talala K, Murtola T, Taari K, Raitanen J, Tammela TL, Auvinen A

Received 7 June 2019

Accepted for publication 23 August 2019

Published 18 October 2019 Volume 2019:11 Pages 923—932


Checked for plagiarism Yes

Review by Single anonymous peer review

Peer reviewer comments 2

Editor who approved publication: Dr Eyal Cohen

Juho Pylväläinen,1–3 Kirsi Talala,4 Teemu Murtola,5–7 Kimmo Taari,8 Jani Raitanen,1,9 Teuvo L Tammela,6 Anssi Auvinen1

1Tampere University, Faculty of Social Sciences (Health Sciences), Tampere, Finland; 2Helsinki University, Faculty of Medicine, Department of Diagnostics and Therapeutics, Helsinki, Finland; 3Helsinki University Central Hospital, Medical Imaging Center, Helsinki, Finland; 4Cancer Society of Finland, Finnish Cancer Registry, Mass Screening Registry, Helsinki, Finland; 5Tampere University, Faculty of Medicine and Health Technology, Prostate Cancer Research Center, Tampere, Finland; 6Tampere University Hospital, Department of Urology, Tampere, Finland; 7Seinäjoki Central Hospital, Department of Surgery, Seinäjoki, Finland; 8University of Helsinki and Helsinki University Hospital, Department of Urology, Helsinki, Finland; 9UKK Institute for Health Promotion Research, Tampere, Finland

Correspondence: Juho Pylväläinen
Helsinki University Central Hospital, Medical Imaging Center, Haartmaninkatu 3, PO Box 180, 00029, Helsinki, Uusimaa, Finland
Tel +358 503239286

Purpose: To evaluate the performance of Charlson Comorbidity Index (CCI) calculated using hospitalization and medication reimbursement databases in predicting mortality.
Patients and methods: Information on hospitalizations was obtained from the national Care Register for Health Care (HILMO) and on medication reimbursements and entitlements for special reimbursements for medications from the Social Insurance Institution for 77,440 men aged 56–71 years at baseline. The subjects were followed up for mortality via Statistics Finland with 20,562 deaths during a 13-year follow-up.
Results: Compared to a CCI score of 0, the age-adjusted hazard ratio for all-cause mortality associated with HILMO-based CCI scores of 1, 2 and 3 or more were 2.39 (95% CI 2.29–2.49), 2.96 (95% CI 2.81–3.13) and 6.42 (95% CI 5.95–6.93) at 13 years. The C-statistic was 0.72 at 1, 0.68 at 5 and 0.66 at 13 years, with only minor improvement over age alone (0.10, 0.06 and 0.04 accordingly). Addition of medication data did not improve predictive abilities and medication-based CCI performed poorly on its own.
Conclusion: The hospitalization-based CCI, as well as that based on both databases, predicts relative mortality adequately, but its discriminative ability diminishes over time. Conditions related to hospitalizations affect survival more than medications.

Keywords: mortality, comorbidity, follow-up studies, hospitalization/statistics and numerical data, drug prescriptions/statistics and numerical data, confounding factors

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]