Validation of the Charlson Comorbidity Index in acutely hospitalized elderly adults: a prospective cohort study

Abstract

Objectives: To determine whether the Charlson Comorbidity Index (CCI) predicts short- and long-term mortality.

Design: Prospective cohort study.

Setting: The medical department of two university hospitals and one community-based hospital.

Participants: Acutely hospitalized individuals aged 65 and older with a mean age of 77.8 ± 7.9, 45.8% male (n = 1,313).

Measurements: In eligible persons, information on demographic characteristics, activities of daily living (modified Katz ADL Index score), and disease-related measures was collected within 48 hours after admission. Follow-up using self-reporting questionnaires was performed at 3 months and 1 year. Functional decline was defined as a decline of at least 1 point on the modified Katz ADL Index score at 12 months from baseline. Mortality data at 3 months and 1 and 5 years were collected from the municipal database.

Results: Logistic regression analysis, adjusted for age and sex, showed that participants with a CCI of 5 or more had higher 3-month (odds ratio (OR) = 3.6, 95% confidence interval (CI) = 2.1-6.4), 1-year (OR = 7.1, 95% CI = 4.2-11.9), and 5-year (OR = 52.4, 95% CI = 13.3-206.4) mortality than those with a CCI of 0. Participants with CCI scores between 1 and 4 also had greater mortality risk at 3 months and 1 and 5 years.

Conclusion: The CCI independently predicts short- and long-term mortality in acutely ill hospitalized elderly adults.

Keywords: Charlson Comorbidity Index; hospital; mortality risk.