Frailty, hospitalization, and progression of disability in a cohort of disabled older women

PURPOSE: To determine the association between a previously validated frailty phenotype and the development of new-onset dependence in activities of daily living, independent of hospitalizations and other established predictors of disability. SUBJECTS: Seven hundred and forty-nine women enrolled in the Women's Health and Aging Study-I who were independent in all activities in daily living when enrolled in the cohort. METHODS: Assessments and interviews were conducted through home visits at 6-month intervals for 3 years. Frailty was classified using a validated phenotype (<3 of the following: weight loss, exhaustion, slow walking, sedentariness, and weak grip), and hospitalizations were identified by self-report. Grouped-time proportional hazard models assessed associations among frailty, hospitalization, and the development of dependence in activities in daily living, adjusting for other factors. RESULTS: Twenty-five percent of the cohort (186/749) were frail at baseline; 56% (104/186) of frail versus 20% (23/117) of nonfrail women developed dependence in activities in daily living (P <.001). In multivariate analysis, frailty was independently associated with the development of dependence in activities in daily living (hazard ratio [HR] = 2.2; 95% confidence interval [CI]: 1.4 to 3.6), adjusting for hospitalization status, age, race, education, baseline functional status, cognition, depressive symptoms, number of chronic diseases, and self-reported health status. Additionally, a dose-response relationship existed between the number of frailty criteria that a woman had and the hazard of subsequent dependence in activities in daily living. CONCLUSION: Frailty, conceptualized as an underlying vulnerability, and hospitalization, which marks an acute deterioration in health, were strongly and independently associated with new-onset dependence in activities in daily living. Additional research is needed to determine if dependence can be minimized by targeting resources and programs to frail older persons.