E CHUNG1,2, D RISI3, J HOLT1, M LONERGAN1, S KOTWAL4,5, K YONG4, B SMYTH5,6, J CHEN1, C WEN1
1Wollongong Hospital, Wollongong, Australia, 2Northern Sydney Clinical School, St Leonards, Australia, 3Research Central, Illawarra Shoalhaven Local Health District, Wollongong, Australia, 4Prince of Wales Hospital, Randwick, Australia, 5The George Institute for Global Health, Sydney, Australia, 6St George Hospital, Kogarah, Australia
Aim: To compare the incidence of AAV between two health districts (Illawarra Shoalhaven local health district (ISLHD), a mixed rural and metropolitan region, and South Eastern Sydney local health district (SESLHD), a metropolitan region) in Australia and its relationship to environmental exposures.
Background: ANCA-associated vasculitis (AAV) is more prevalent in rural areas of Australia compared to metropolitan areas suggesting a role of environment in disease pathogenesis. However, the prevalence of environmental risk factors in Australian AAV patients has not been described.
Methods: Cases of AAV from 2002 to 2017 were retrospectively identified from ISLHD and SESLHD using electronic medical records. Eligible participants were invited to complete a standardised questionnaire examining their exposure to silica, solvents, metal, dust, farming, gardening, and sunlight.
Results: 156 cases of AAV were identified from 2002 to 2017. A higher cumulative incidence of AAV was observed in the ISLHD (184.2 [95% confidence interval (CI) 143.6-232.7] per million) compared to SESLHD (102.6 [95% CI 82.1-126.8] per million). Over 50% of the cohort reported high levels of exposure to silica and solvents. There was no significant relationship between region and exposure to silica (p=0.96), solvents (p=0.44), metal (p=0.33), dust (p=0.25), farming (p=0.90), gardening (p=0.93), or sunlight (p=0.55).
Conclusions: We found a higher incidence of AAV in ISLHD compared to SESLHD with high levels of exposure to silica and solvents in both regions. Prospective systematic collection of data, such as a registry of AAV, is warranted to further explore the relationship between environmental exposures and AAV.
Edmund Chung is a 3rd year renal advanced trainee with an interest in glomerular diseases. He has completed his Bachelor of Medical Studies and Doctor of Medicine at the University of New South Wales in 2013 and a Master of Clinical Epidemiology at University of Sydney in 2015, and has subsequently published systematic reviews with the Cochrane Kidney and Transplant Group. He aspires to better underlying disease mechanisms in autoimmune glomerular diseases, identify novel therapeutic strategies, and translate them into clinical care.