Acessibilidade / Reportar erro

Accuracy of two prognostic indexes to predict mortality in older adults with advanced dementia

ACURÁCIA DE DOIS ÍNDICES PROGNÓSTICOS PARA PREDIÇÃO DE MORTALIDADE DE IDOSOS COM DEMÊNCIA AVANÇADA

ABSTRACT.

Dementia is a cause of disability among older adults. Accessing advanced dementia prognosis is a challenge.

Objective:

The objective of this study was to evaluate the accuracy of the Charlson and Carey indexes in predicting 3-year survival of older adults with advanced dementia.

Methods:

This is a retrospective cohort study of 238 patients aged ≥60 years with advanced dementia from an outpatient clinic and classified as stage ≥6A by using the Functional Assessment Staging scale. We excluded patients with missing data. We reviewed the semi-structured interview (clinical, sociodemographic, and functional data) from the baseline visit. This information was used to calculate 3-year mortality risks according to the Charlson and Carey indexes. We used Cox proportional hazard models to evaluate the associations of all-cause mortality with both indexes, adjusted for sociodemographic variables. We used Harrell’s C measure to determine the discrimination. We calculated the absolute differences between observed and predicted 3-year mortality risks for each index for calibration.

Results:

In 238 patients, the average age was 80.5±7.8 years, with 36% being men. The median follow-up time was 1.8 years (0.05–3.0). The 3-year all-cause mortality rate was 50% (119 deaths). The Carey index was associated with mortality, with one point increase related to a 15% increase in the mortality risk (hazard ratio [HR]=1.15, 95% confidence interval (95%CI) 1.06–1.25, p=0.001), even after adjustment. Accuracy for the Charlson index and Carey index was 0.55 (95%CI 0.49–0.60) and 0.60 (95%CI 0.52–0.62), respectively, with no difference between them (p=0.44).

Conclusions:

Both indexes had poor discrimination and calibration performances in predicting 3-year mortality in patients with advanced dementia.

Keywords:
Aged; Dementia; Prognosis; Survival Analysis; Mortality

Academia Brasileira de Neurologia, Departamento de Neurologia Cognitiva e Envelhecimento R. Vergueiro, 1353 sl.1404 - Ed. Top Towers Offices, Torre Norte, São Paulo, SP, Brazil, CEP 04101-000, Tel.: +55 11 5084-9463 | +55 11 5083-3876 - São Paulo - SP - Brazil
E-mail: revistadementia@abneuro.org.br | demneuropsy@uol.com.br