Objective: To determine the relationship between mortality and level of frailty using the Frailty Index–Comprehensive Geriatric Assessment (FI–CGA) among older adults at a 12-month follow-up. Materials and methods: A descriptive, observational and prospective study with non-probabilistic sampling conducted with patients over 60 years of age from the Geriatrics Service. Using the FI–CGA, frailty was diagnosed if the score was greater than or equal to 0.2 at the different levels of care: acute care unit, day hospital, outpatient clinic and house call. Moreover, a follow-up was conducted 12 months following their telephone consultation. In case of death, the event and cause were confirmed in the Sistema Informático Nacional de Defunciones (SINADEF, National Death Computer System) of the Ministry of Health of Peru. Patients who died from coronavirus complications were excluded. To det...