21st International Vasculitis Workshop. Abstracts Book

Background/ Objectives: Research into ANCA-associated vasculitis (AAV) is hampered by the rarity of the disease and thesubsequent small sample sizes of observational cohorts. This is further aggravated by the observational cohorts being containedin fragmented data pools and lacking standardisation to allow for interoperability. FAIRVASC is a Europe-wide research project,which has developed an infrastructure linking 7 existing AAV registries into a single European dataset, to allow high-qualityresearch on natural disease history and clinical outcomes.This analysis highlights the capabilities of the FAIRVASC infrastructure to assess clinical outcome of AAV across the federatedregistries.Methods: Within the FAIRVASC project, 7 national/regional AAV registries were harmonized using a semantic web approach,including the creation of a dedicated AAV ontology, to enable semantic interoperability. For this study, aggregated data regardingmortality rate (/100 person years, with related 95% Confidence Intervals) per diagnosis were retrieved through the FAIRVASC webinterface, a tool that allows federated querying over linked registries. We defined mortality rate in the first and second year postdiagnosis, and in years 3-5 and after 5 years.Results: Mortality queries were posed over the FAIRVASC registries, namely RKD (Republic of Ireland, 677 patients), GFEV(France, 2814 pts), ANCA (Czech Republic, 377 pts), PolVas (Poland, 944 pts), Skane (Sweden, 374 pts), Italivas (Italy, 301pts), GeVas (Germany, 169 pts). Mortality rates, stratified by diagnosis and registry, are reported in Table 1. The lowest mortalitywas reported for eosinophilic granulomatosis with polyangiitis (EGPA), with rates ranging from 0 to 2.5 cases/100 person-yearsdepending on the post-diagnosis interval. Conversely, the highest mortality was found for microscopic polyangiitis (MPA), withmortality rates ranging from 6.7 to 22.3 across registries in the first year after diagnosis, and from 3.9 to 7.4 after >5 years fromdiagnosis. In patients with granulomatosis with polyangiitis (GPA), mortality rates ranged from 3.3 to 8.2 in the first year afterdiagnosis and from 0.7 to 4.5 after >5 years from diagnosis.Conclusions: The FAIRVASC infrastructure is a reliable tool to query multiple AAV registries for assessing long-term clinicaloutcomes of AAV in a large number of patients, in a privacy-compliant manner.Disclosures: None.