Cumulative ionizing radiation exposure in patients with end stage kidney disease: a 6-year retrospective analysis.

Objective: To quantify cumulative exposure to ionizing radiation in patients with end stage kidney disease (ESKD). To investigate factors which may be independently associated with risk of high cumulative effective dose (CED).

Materials And Methods: The study had local institutional review board ethical approval. We conducted a retrospective study of 394 period prevalent ESKD patients attending a single tertiary referral centre between 2004 and 2009. Patient demographics were obtained from case records. Details of radiological investigations were obtained from the institutional radiology computerized database. CED was calculated using standard procedure specific radiation levels. High exposure was defined as CED > 50 mSv, an exposure which has been reported to increase cancer mortality by 5%. Data were compared using Pearson χ(2) and Mann-Whitney U test or Kruskal-Wallis tests.

Results: 394 patients were followed for a median of 4 years (1518 patient years follow-up). Of these 63% were male. Seventeen percent of patients had a CED of >50 mSv. Computed tomography (CT) accounted for 9% of total radiological studies/procedures while contributing 61.4% of total study dose. Median cumulative dose and median dose per patient year were significantly higher in the hemodialysis (HD) group (15.13 and 5.79 mSv, respectively) compared to the post-transplant group (2.9 and 0.52 mSv, respectively) (P < 0.001).

Conclusion: ESKD patients are at risk of cumulative exposure to significant levels of diagnostic radiation. The majority of this exposure is imparted as a result of CT examinations to patients in the HD group.