Socio-economic status and incidence of renal replacement therapy: A registry study of Australian patients

Abstract

BackgroundSocio-economic disadvantage has been linked to higher incidence of end-stage kidney disease in developed countries. Associations between socio-economic status (SES) and incidence of renal replacement therapy (RRT) have not been explored for different kidney diseases, genders or age groups in a country with universal access to healthcare.MethodsWe investigated the incidence of non-indigenous patients commencing RRT in Australia in 2000-09, using the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry. Patient postcodes were grouped into deciles using a standard SES index. We analysed incidence by five groups of kidney diseases, age groups, gender and geographic remoteness.ResultsIncidence of RRT decreased with increasing area advantage. Differences were most evident for the most disadvantaged areas [markedly increased burden; incident rate ratio (IRR) 1.27; 95 confidence interval (CI) 1.18-1.38] and most advantaged decile (decreased burden, IRR 0.76; 95 CI 0.72-0.81), compared with decile 5. Patients with diabetic nephropathy showed the greatest disparities: residents of the most disadvantaged decile were 2.38 (95 CI 2.09-2.71) times more at risk than the most advantaged decile. Congenital and genetic kidney diseases showed lesser gradients-the most disadvantaged decile was 1.28 times (95 CI 0.98-1.68) more at risk. SES was not associated with incidence for patients older than 69 years.DiscussionThese SES gradients existed, despite all Australians having access to healthcare. Diseases associated with lifestyle show the greatest gradients with SES. © The Author 2012. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.