Long-term patient survival in a Swedish population-based cohort of patients with ANCA-associated vasculitis

OBJECTIVES: Patients with antineutrophil cytoplasmatic antibodies-associated vasculitides (AAV) exhibit higher mortality than the general population. In the current study, we assessed whether cluster affiliation based on clinical presentation might predict mortality. METHODS: With case record review, the outcomes for a population-based cohort of patients diagnosed with AAV in southern Sweden (catchment area of 0.7 million inhabitants) between 1997 and 2010 were assessed. Based on organ involvement at presentation, the cohort was stratified into the following clusters: gastrointestinal, cardiovascular, non-renal, renal with proteinase 3 (PR3) and renal without PR3. Cluster affiliation, demographics, clinical and laboratory values at entry were tested as prognostic factors for survival in multivariable models. RESULTS: 195 patients (98 female) with a median age of 69 years (IQR 55–77) at diagnosis were included in the cohort. The median time of follow-up was 4 years for the 98 patients (50%) who died during follow-up and 11 years for those alive at end of follow-up. The 1-year, 2-year, 5-year and 10-year survival was 87%, 82%, 70% and 55%, respectively. Prognostic factors for survival were sex, age, renal function and cluster affiliation. The mortality of patients with AAV was significantly increased compared with the general population except in the non-renal cluster. The cardiovascular and gastrointestinal clusters showed the highest mortality. CONCLUSION: Even though the mortality in patients with AAV is increased compared with the general population this does not apply to patients without gastrointestinal, cardiovascular or renal involvement at diagnosis. We suggest that the initial clinical presentation is an important predictor for survival.