Treatment and its side effects in ANCA-associated vasculitides - Study based on POLVAS registry data

Purpose: The aim of this study is to present the treatment modalities and associated side effects in a Polish nation-wide ANCA-associated vasculitides (AAV) patients' cohort. Materials and methods: Retrospective analysis of patients diagnosed with AAV between 1990 and 2016, included in the POLVAS registry was performed. Standard descriptive statistic methods were used with an emphasis on the treatment modalities. Results: There were 625 patients diagnosed with AAV included in this study: 417 cases of granulomatosis with polyangiitis (GPA; 66.7%), 106 cases of microscopic polyangiitis (MPA; 17.0%) and 102 cases of eosinophilic granulomatosis with polyangiitis (EGPA; 16.3%). The mean age at the date of diagnosis was 50.4 (+/- 15.7) years and the median observational period amounted to 4.0 (2.0-8.0) years. Glucocorticosteroids (GCs) were the medicaments most frequently used for remission induction (593/622; 95.3%), followed by cyclophosphamide (487/622; 78.3%), rituximab (44/622; 7.1%), and methotrexate (39/622; 6.3%). GCs were also most frequently administered for maintenance therapy (499/592; 84.3%), followed by azathioprine (224/592; 37.8%), methotrexate (136/592; 23.0%) and mycophenolate mofetil (99/592; 16.7%). The median cumulative doses of cyclophosphamide and rituximab equalled 7.99 g (4.18-14.0) and 2000 mg (1500-2800), respectively. The most commonly observed adverse events included: infections - 214/551 cases (38.8%), which were associated with the time of observation (OR = 1.05; 95% CI 1.01-1.10), the use of GCs intravenous pulses (OR = 2.76; 95% CI 1.68-4.54) and need for haemodialysis (OR = 1.73; 95% CI 1.10-2.71). Conclusions: Polish patients with AAV were predominantly treated according to appropriate guidelines. The most frequent adverse events were typical for usually administered immunosuppressive treatment.