Frailty and rheumatic diseases: evidence to date and lessons learned.

Frailty represents a dynamic multisystem state of reduced physiological reserve that increases vulnerability to adverse health outcomes. Frailty occurs prematurely in adults with immune-mediated rheumatic diseases and is emerging as an important risk factor for adverse outcomes in these conditions. In this Series paper, we present a conceptual overview of frailty and its prevalence among patients with immune-mediated rheumatic diseases. We discuss putative mechanisms of frailty relevant to these diseases, tools for frailty measurement, and potential implications of frailty assessment for clinical care. We also explore the complex inter-relationship between frailty, inflammation, and disease activity in immune-mediated rheumatic diseases. As insight is gained into the epidemiology and mechanisms of frailty among patients with immune-mediated inflammatory rheumatic diseases, the possibility of targeting frailty with an intervention that could complement standard disease-modifying therapies to prevent adverse outcomes and improve health-related quality of life becomes closer to reality.