The Limitations of Frailty Assessment Tools in ANCA-Associated Vasculitis

Anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) can be associated with a high burden of morbidity and mortality in an ageing population. It is increasingly recognised that individualised management is needed. Few studies have looked specifically at frailty related outcomes in AAV and a gap remains in understanding the application of frailty assessment tools in these patients. We carried out a single centre, cohort study between 2017 to 2022. Forty-one patients who had newly diagnosed or relapsing AAV and aged ≥65 years were included. The Clinical Frailty Scale (CFS) score at presentation was assessed by health care practitioners and interval CFS scores were carried out a minimum of 6 weeks from diagnosis. The aim was to determine if patients living with frailty had worse outcomes or if their perceived frailty improved with immunosuppressive treatment. The median CFS at diagnosis was 4 (vulnerable) and this remained at follow up. There was no significant interval change in CFS (P=0.16) suggesting that the patients did not become frailer and instead there was a tendency towards improved frailty scores at re-assessment. There was no significant difference in end stage kidney disease between those with higher (>5) or lower (≤5) CFS (P=1.0), although crude mortality was higher among those with an initial CFS >5 (P=0.03). Overall, we demonstrated that CFS has limitations in determining patients that may be frail as a result of disease burden with the potential to improve with treatment and clinicians should be mindful of this when making decisions relating to management.