385. Health Related Quality of Life Among Patients with Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis

Background: Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is a debilitating disease that can have a significant impact on a patient’s quality of life. The aim of this study was to assess the longitudinal quality of life amongst those diagnosed with AAV using the EQ-5D instrument, which allows for calculation of quality-adjusted life years (QALYs.) Methods: 343 patients with AAV participated in this study, of which 191 (55.7%) were male, resulting in 2746 episodes. The EQ-5D-5L standardised instrument was used to evaluate health related quality of life in the domains of mobility, self-care, usual activities, pain/discomfort, anxiety/depression and to generate a summary index score. Overall health was also rated using a visual analogue scale (0-100). EQ-5D questionnaires were completed during routine nephrology clinic attendances and through a vasculitis patient support smartphone app. We used a mixed-effects model to control for multiple entries relating to individual patients. Results: A lower quality of life was seen amongst those with AAV (median index value 0.80, overall population average 0.856). The mean visual analogue scale score was 75.6±17.3 (overall population average 82.8, Fig 1). Patients’ pain and discomfort level (mean 1.95) was most affected while self-care (mean 1.33) was least affected (Fig 1). An increase in BVAS tightly correlated with a reduction in quality of life. The index score decreased with increasing age. Using a median survival rate of 6.16 years for patients with small vessel vasculitis, we calculated the QALYs for this population as 4.9 years. Conclusions: We have defined for the first time the EQ-5D index value over the full disease course in patients with AAV. Other studies have demonstrated a reduction in quality of life during active disease using the AAV–PRO questionnaire and the Medical Outcomes Study Short Form-36. A decrease in work productivity has also been noted. Previously reported mean index values of 0.72 and 0.76 were lower than our observed values, although both are significantly reduced compared to population norms. In conclusion, this research highlights the negative impact of AAV on patients’ lives. Disclosures: The authors have no conflicts of interest to declare