Background:IgA vasculitis is generally considered to be a self-limiting condition, but this is at odds with the increased mortality observed in adult patients with IgA vasculitis (1).Objectives:With sparse data on prognostic factors in IgAV, we investigated whether pre-existing conditions are risk factors for mortality in adult IgAV patients.Methods:Observational population-based cohort study using state-wide linked longitudinal health data for adults with IgAV (n=267) and matched controls (n=1080) between 1980-2015. Charlson comorbidity index (CCI) and serious infections (SI) were recorded over an extensive lookback period prior to diagnosis. Date and causes of death were extracted from the WA Death Registry. Mortality rate (deaths/1000 person-years) ratios (MRR) and time dependent survival analysis assessed the risk of death. Age and gender specific mortality rate data were obtained from the Australian Bureau of Statistics.Results:During 9.9 (±9.8) years lookback IgAV patients accrued higher CCI scores (2.60 vs1.50 p<0.001) and had higher risk of SI (OR 8.4, p<0.001), not fully explained by CCI scores. During 19 years follow-up, the risk of death in IgAV patients (n=137) was higher than in controls (n=397) (MRR 2.06, CI 1.70-2.50, p<0.01) and the general population (SMRR 5.64, CI 4.25, 7.53, p<0.001). Survival in IgAV was reduced at five (72.7 vs. 89.7 %) and twenty years (45.2% vs. 65.6 %) (both p<0.05). CCI (HR1.88, CI:1.25 - 2.73, p=0.001), renal failure (HR 1.48, CI: 1.04 - 2.22, p=0.03) and prior SI (HR 1.48, CI:1.01 – 2.16, p=0.04) were independent risk factors. Death from infections (5.8 vs 1.8%, p=0.02) was significantly more frequent in IgAV patients.Conclusion:Premorbid accrual of comorbidity is increased and predicts premature death in IgAV patients. However, comorbidity does not fully explain the increased risk of serious infections prior to diagnosis or the increased mortality due to infections in IgAV.References:[1]Villatoro-Villar M, Crowson CS, Warrington KJ, Makol A, Ytterberg SR, Koster MJ. Clinical Characteristics of Biopsy-Proven IgA Vasculitis in Children and Adults: A Retrospective Cohort Study. Mayo Clin Proc. 2019;94(9):1769-80.Acknowledgements:The authors would like to acknowledge the support of the Arthritis Foundation of WA and acknowledge the Western Australian Data Linkage Branch, the Western Australian Department of Health, and the data custodians of, the Hospital and Morbidity Data Collection, the Emergency Department Data Collection the WA Cancer Register and the WA Death Register for their assistance with the study.Disclosure of Interests:None declared
AB0393 PRE-EXISTING MORBIDITY AS A RISK FACTORS FOR MORTALITY IN IgA VASCULITIS
