Prefrailty subtypes differentially predict 5-year mortality in the functionally independent geriatric population

Abstract

Introduction: Both frailty and prefrailty (PF) are related to mortality. However, there is no consensus about the PF subtypes for prediction of the mortality risk. We aimed to compare the 5-year mortality of functionally independent geriatric outpatients with nonfrailty, different PF subtypes and frailty.

Methods: This was a single-center, retrospective cohort study. Community-dwelling older adults who visited the geriatric outpatient clinic in a healthcare institution in Taiwan were enrolled. PF1 was defined based on exhaustion and/or body weight loss whereas PF2 was defined by one or two of the following criteria: weakness, slowness, and low physical activity. Frailty was defined by three or more above criteria. Demographics and results of comprehensive geriatric assessment were compared and Kaplan-Meier survival analysis was used to determine the 5-year survival among the nonfrail, PF1, PF2 and frail groups.

Results: Of the 982 participants, the proportion of PF and frailty was high (PF 45.7% and frailty 24.5%). The cumulative 5-year survival rate of the nonfrail group, PF1, PF2 subgroups and frail group was 98.6%, 95.8%, 89.1% and 81.3% respectively. Age, male sex, PF2 subtype and frailty were significantly associated with 5-year mortality [hazard ratio (95% confidence interval) 1.05 (1.01-1.08), 1.96 (1.08-3.57), 5.18 (1.57-17.09), and 6.87 (2.05-23.04), respectively].

Discussion and conclusion: The proportion of PF and frailty was high in old outpatient population with functional independence. PF2 subtypes and frailty could influence the 5-year mortality risk in these participants. Identifying PF2 participants earlier and instituting prompt intervention may be beneficial in older patients.

Keywords: Functional independence; Mortality; Older people; Phenotype; Prefrailty.