Background <p>Frailty has emerged as a common and clinically relevant condition in rheumatoid arthritis (RA). However, comprehensive evidence linking frailty with both physical and mental health outcomes in RA remains limited, particularly in low- and middle-income settings. This study aimed to explore the association between frailty and adverse health outcomes in participants with RA, focusing on disease activity, physical function, anxiety, depression, and health-related quality of life (HRQoL).</p> Methods <p>A multicenter cross-sectional study was conducted in Tianjin, China, from November 2023 to August 2024. Frailty was assessed using the FRAIL scale, with multiple linear regression models applied to examine the associations between frailty status and the specified health outcomes. Frailty and pre-frailty were treated as independent variables in all models. Covariates included demographic, lifestyle, and clinical factors, and full adjustment was performed in the final model.</p> Results <p>A total of 823 participants with RA were enrolled. After full adjustment, frailty was significantly associated with higher disease activity, poorer physical function, elevated anxiety and depression, and lower HRQoL (all <i>P</i> &lt; 0.001). Pre-frailty was also significantly associated with higher disease activity, worse physical function, greater depression, and lower HRQoL (all <i>P</i> &lt; 0.001) but not with anxiety (<i>P</i> = 0.786).</p> Conclusions <p>Frailty is a significant indicator of adverse health outcomes in RA, and even pre-frailty signals a higher vulnerability to poor health outcomes. Incorporating frailty assessment into routine RA management and identifying individuals at the pre-frail stage may provide critical opportunities for early intervention and improved long-term outcomes.</p>