An update on cognitive frailty: Its definition, impact, associated factors and underlying mechanisms, and interventions.

Since the concept and operational definition of "cognitive frailty" (simultaneous presence of physical frailty and cognitive impairment without concurrent dementia) were proposed by the International Academy of Nutrition and Aging and the International Association of Gerontology and Geriatrics, cognitive frailty has been widely investigated. This review is intended to address the operational definition of cognitive frailty, its consequences, contributing factors and underlying mechanisms, as well as interventions for cognitive frailty. Although the definitions and assessments of cognitive frailty vary among researchers, older adults with both physical frailty and cognitive impairment are shown to be at higher risk of adverse health outcomes, including death, disability, hospitalization and incident dementia, than those with either condition alone. While the underlying mechanisms of cognitive frailty are still unclear, factors shown to be associated with cognitive frailty include sociodemographic factors, social status, nutritional status, geriatric syndrome, physical and cognitive activities, functional status, comorbidities, medication use, gut-derived metabolites and structural changes in the brain. Accumulating evidence indicates the need for comprehensive geriatric assessment that helps identify the possible causes of cognitive frailty and develop a multimodal individualized intervention to prevent adverse health outcomes for older adults with cognitive frailty. Further studies are required to clarify the mechanisms through which physical frailty and cognitive impairment interact to accelerate adverse health outcomes, particularly cognitive outcomes. In addition, for older adults with cognitive frailty, an effective flow diagram from primary screening through comprehensive assessment to multidimensional intervention needs to be developed for future implementation in both clinical and community settings. Geriatr Gerontol Int 2022; 22: 99-109.