Frailty-related multiple health outcomes in older individuals: an umbrella review of systematic reviews and meta-analyses

Frailty and its subtypes including physical, cognitive, multidimensional and social frailty have been reported to be associated with a wide range of adverse outcomes in older adults. However, little effort has been made to collate and assess the credibility of this evidence. The aim of this umbrella review was to systematically evaluate the certainty of associations between frailty subtypes and adverse health outcomes across community, nursing home and hospital settings. We registered an a priori protocol with PROSPERO (CRD420251123204) and searched five databases from inception to August 2025. We included 37 systematic reviews and meta-analyses. Methodological quality was assessed using a measurement tool to assess systematic reviews (AMSTAR) 2. Evidence credibility was evaluated using predefined statistical criteria. Non-pooled outcomes were judged by the grading of recommendations assessment, development, and evaluation (GRADE) approach. A total of 31 frailty-related outcomes and 11 prefrailty-related outcomes were identified, with a corrected covered area of 0.98%. Pooled analyses showed suggestive evidence for associations of frailty with mortality (pooled relative risk (RR) 2.07) and prefrailty with mortality (pooled RR 1.38). Frailty was also associated with higher risks of hospitalisation, institutionalisation, falls, fractures, cognitive decline and depression. Cognitive frailty showed a markedly elevated risk of dementia (pooled RR 3.75). Multidimensional frailty had the highest mortality risk. Social frailty was associated with mortality and functional decline. Hospital-based evidence indicated that frailty predicted delirium, in-hospital death and post-discharge mortality. Although most non-pooled outcomes presented low to moderate certainty, the direction of effects was consistent. These findings support early detection and multidimensional management of frailty, particularly cognitive and social frailty.