P129 Radiation Exposure among Adults with Cystic Fibrosis: Trends and Themes

Introduction Although the average UK dose from medical ionising radiation is 0.44 mSv (PHE-CRCE-026, 2011), people with CF (pwCF) undergo many such investigations for the management of their disease. With improving survival their life-time exposure, a risk factor for the development of malignancy, may be important. We therefore monitored this radiation exposure in our adult CF center and wished to look for any trends over time. Methods We calculated the estimated effective dose (EED) of ionising radiation using standard reference values (HPA-CRCE-034, 2011; PHE-CRCE-013, 2010), and applied this to all procedures carried out in pwCF at our centre 2017–19, comparing it to that in 2010. Results There were 2,630 investigations in 327 pwCF 2017–19 and 693 in 253 in 2010 (mean [SD] yearly EED 1.49 ± 3.85 mSv, versus 1.66 ± 3.76 mSv respectively [p=0.56]): 217 pwCF in 2017–19 had an average yearly EED <0.44 mSv. A similar number of examinations were carried out in each time period (2.7 versus 2.8 per person), predominantly thoracic (76% versus 84%), of which most was CT imaging (89% versus 80% respectively). In 2017–19, EED was higher in those with chronic Pseudomonas aeruginosa infection (1.56 ± 3.90 mSV versus 1.27 ± 3.68 mSv; p<0.001), non-tuberculous mycobacterium (NTM) (1.52 ± 2.57 mSv versus 1.49 ± 4.05 mSv, p<0.001) and CF-related diabetes (1.56 ± 4.04 mSv versus 1.14±3.65 mSv; p<0.001). Thirteen pwCF (4%) had a yearly average EED of ≥10 mSv (16.33 m ± 13.07Sv in those 7 with malignancy). Conclusions Although radiation exposure remains high amongst pwCF, in keeping with other published reports (Plant et al), there was no upward trend in EED over time, and a similar number of procedures were performed per person. As expected, pwCF with more complications had higher radiation exposure, underlining the need to maintain vigilance for comorbidities in this complex chronic disease.