Validation study of C harlson Comorbidity Index in predicting mortality in C hinese older adults

Aim The Charlson Comorbidity Index ( CCI ) is commonly studied for predicting mortality, but there is no validation study of it in C hinese older adults. The objective of the present study was to validate the use of CCI in C hinese older adults for predicting mortality. Method We carried out a retrospective cohort study from 2004 to 2013 for patients discharged from a geriatric day hospital in H ong K ong. Comorbidity was quantified using CCI , and patients were divided into six groups according to their score of CCI : CCI ‐0, CCI ‐1, CCI ‐2, CCI ‐3, CCI ‐4 and CCI ≥ 5. Other data collected included demographics, and functional, nutritional, cognitive and social assessment. The outcome measure was 1‐year mortality. Results At 1‐year follow up, 3.8% ( n  = 17), 5.9% ( n  = 37), 9.2% ( n  = 35), 12.9% ( n  = 20), 16.9% ( n  = 23) and 19.3% ( n  = 60) of CCI ‐0, CCI ‐1, CCI ‐2, CCI ‐3, CCI ‐4 and CCI ≥ 5 died, respectively ( P  < 0.001). Multivariate analysis showed that CCI ‐1, CCI ‐2, CCI ‐3, CCI ‐4 and CCI  ≥ 5 have a hazard ratio ( HR ) of 1.34 (confidence interval [ CI ] 1.04–2.12), 2.18 ( CI 1.03–4.61), 3.44 ( CI 1.52–7.81), 3.74 ( CI 1.35–10.39) and 4.63 ( CI 2.28–9.43), respectively, compared with CCI ‐0. The area under the curve of the receiver operating characteristic curves of CCI in predicting 1‐year mortality for older adults was 0.68 ( CI 0.64–0.72). Conclusion There is a significant dose–response relationship in the hazard ratio between CCI and 1‐year mortality in C hinese older adults, but involvements of functional, nutritional and social assessments are important for comprehensive quantification of health status in older adults. Geriatr Gerontol Int 2014; 14: 452–457.