MA MOHD HASHIM1, C MEYERKORT1, A NAIDOO2, AS ABEYARATNE1, M SUNDARAM1, N KANGAHARAN5, A KOOKANA4, P LAWTON3, A CASS3, JT HUGHES1,3, SW MAJONI1,2,3
1Royal Darwin Hospital, Department of Nephrology, Division of Medicine, Tiwi, Darwin, Northern Territory; 2Northern Territory Medical Program, Flinders University School of Medicine, Tiwi, Darwin, Northern Territory; 3Wellbeing and Preventable Chronic Disease Division, Menzies School of Health Research; 4Regional Imaging Royal Darwin and Darwin Private Hospitals; 5Royal Darwin Hospital, Division of Medicine, Tiwi, Darwin, Northern Territory
Aim: To determine the cumulative exposure of ionising radiation in patients receiving renal replacement therapy (RRT) by estimating the cumulative effective dose (CED) and demonstrating the trends in radiation exposure by imaging modality.
Background: RRT patients undergo medical imaging procedures over time due to the chronicity of their disease, investigation of comorbid medical conditions and management of vascular access problems. To date, no Australian study has characterized the CED of patients on RRT. This abstract reports findings for 39.7% of the total cohort, for whom CED had been calculated at the time for submission.
Methods: CED were obtained for all adult RRT patients recorded in hospital radiology and angiography databases in Darwinfrom 2008 to 2013. Patients with a pre-existing diagnosis of malignancy were excluded. The radiation exposure was quantified in millisieverts (mSv) and calculated using reference effective doses.
Results: 124 patients (45% males) were included in initial analysis, a subset of 312 patients in total. 85.6% were Indigenous, and 5.3% receiving peritoneal dialysis. The mean age was 54.1 (11.8) years. The median cumulative dose per patient over the study period was 21 mSv (IQR 8.1 to 46.2). 69 patients (56.7%) received an annual cumulative effective radiation dose over 20mSv, the upper averaged annual limit for occupational exposure. 13% received total CED over 75mSv, a value associated with an increased risk of cancer-related mortality. Indigenous patients received higher dose (81.4% vs 18.6%, p=0.02). Haemodialysis was associated with higher dose CT scans and angiographies including fistula procedures contributed the highest proportion of the dose.
Conclusions: There is significantly greater CED in patients on RRT. Examining the association with clinical outcomes requires further study.