Discrimination ability of comorbidity, frailty, and subjective health to predictmortality in community-dwelling older people: Population based prospective cohort study

Objective: To investigate the added value of comorbidity, frailty, and subjective health tomortality predictions in community-dwelling older people and whether it changes with increasing age. Participants: 36,751 community-dwelling subjects aged 50-100 from the longitudinal Survey of Health, Ageing, and Retirement in Europe. Methods: Mortality risk associatedwith Comorbidity Index, Frailty Index, Frailty Phenotype, and subjective health was analysed using Cox regression. The extent to which health indicators modified individual mortality risk predictions was examined and the added ability to discriminate mortality risks was assessed. Main outcomemeasures: Three-year mortality risks, hazard ratios, change in individualmortality risks, three-year area under the receiver operating characteristic curve (AUC). Results: Three-year mortality risks increased 41-folds within an age span of 50 years. Hazard ratios per change in health indicator became less significant with increasing age (p-value b 0 u 001). AUC for three-yearmortality prediction based on age and sex was 76 u 9% (95% CI 75 u 5% to 78 u 3%). Information on health indicators modified individual three-year mortality risk predictions up to 30%, both upwards and downwards, each adding b2% discriminative power. The added discrimination ability of all health indicators gradually declined from an extra 4% at age 50-59 to b1% in the oldest old. Trends were similar for one-year mortality and not different between sexes, levels of education, and household income. Conclusion: Calendar age encompasses most of the discrimination ability to predictmortality. The added value of comorbidity, frailty, and subjective health to mortality predictions decreases with increasing age. (C) 2017 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.