Abstract
Frailty is an independent risk factor linked to a higher likelihood of various diseases. With limited healthcare resources worldwide - especially in developing countries - the factors that contribute to frailty need to be understood across different populations and a universal model needs to be developed. This could help reduce the burden on healthcare systems and lessen the negative health effects of frailty. This review aims to summarize current evidence on the key factors influencing frailty and its impact on disease outcomes in different countries. The goal is to facilitate the development of strategies that can help prevent or even reverse frailty. Studies were included if they examined physical frailty using validated assessment tools in older adults and explored how various factors affect its development and progression. A comprehensive search of the PubMed database was conducted from March 1 to March 31, 2024 using the keywords "vulnerability" and "influencing factors." Studies published between January 1, 2001, and March 31, 2025 were considered. A total of 1,614 articles were initially identified, with 50 studies ultimately meeting the predefined inclusion and exclusion criteria. The findings indicate that frailty is influenced by a wide range of interrelated risk and protective factors, which in turn have various effects on different disease outcomes. These interconnected factors highlight both the complexity and the potential for targeted intervention. The review provides a comprehensive understanding of the factors associated with frailty in older adults across diverse settings and underscores the urgent need to develop a robust, evidence-based frailty model to facilitate the early identification, prevention, and possibly reversal of frailty.