A New Functional Classification Based on Frailty and Disability Stratifies the Risk for Mortality Among Older Adults: The FRADEA Study

Objectives: The aim of the current study was to investigate whether a new functional classification, based on basic (BADL) and instrumental (IADL) activities of daily living and frailty, is associated with mortality in older adults during 10 years of follow-up. Design: Cohort study, with a follow-up of 10 years. Setting and participants: A total of 924 participants aged 70 and older from the Frailty and Dependence in Albacete (FRADEA) study, a population-based sample of Spanish older adults. Measures: At baseline, a new functional classification of 8 categories was constructed with limitations in BADL using the Barthel Index, limitations in IADL using the Lawton IADL Index, and the criteria of the frailty phenotype. Associations with 10-year mortality were assessed using Kaplan-Meier curves and Cox proportional hazard models. Results: The risk of mortality gradually increased toward the less functionally independent end of the classification. The presence of mild, moderate, or severe BADL impairment was associated with mortality, in models adjusted for age, sex, comorbidity and institutionalization. The analyses also revealed that those who were BADL independent, IADL dependent and prefrail [hazard ratio (HR) = 2.27, 95% confidence interval (CI) = 1.22-4.20], and those who were BADL independent and frail (HR = 3.74, 95% CI = 1.88-7.42) had an increased risk of mortality. Conclusions/implications: A new functional classification composed of BADL, IADL, and frailty representing the functional continuum is effective in stratifying the risk for mortality in older adults. Frailty is a high-mortality-risk state close to subjects with mild disability in BADL, needing an intensive specialized approach. Prefrailty with any impairment in IADL has an intermediate mortality risk and should be offered primary care interventions.