The Long-Term Impact of Ionizing Radiation on DNA Damage in Patients Undergoing Multiple Cardiac Catheterizations

Ionizing radiation (IR) exposures have increased exponentially in recent years due to the rise in diagnostic and therapeutic interventions. A number of small-scale studies investigated the long-term effect of IR on health workers or immediate effects of IR on patients undergoing catheterization procedures; however, the long-term impact of multiple cardiac catheterizations on DNA damage on a patient population is not known. In this study, the effects of IR on DNA damage, based on micronuclei (MN) frequency and 8-hydroxy-2'-deoxyguanosine (8-OHdG) as markers in peripheral lymphocytes, were evaluated in patients who previously underwent multiple cardiac catheterization procedures. Moreover, genetic polymorphisms in genes PARP1 Val762Ala, OGG1 Ser326Cys, and APE1 Asn148Glu as a measure of sensitivity to radiation exposure were also investigated in the same patient population. The patients who underwent ≥ 3 cardiac catheterization procedures revealed higher DNA injury in comparison to the patients who underwent ≤ 2 procedures, documented with the presence of higher level of MN frequency (6.4 ± 4.8 vs. 9.1 ± 4.3, p = 0.002) and elevated serum 8-OHdG levels (33.7 ± 3.8 ng/mL vs. 17.4 ± 1.9 ng/mL, p = 0.001). Besides, OGG1 Ser326Cys and APE1 Asn148Glu heterozygous and homozygous polymorphic types, which are related with DNA repair mechanisms, were significantly associated with MN frequency levels (p = 0.006 for heterozygous and p = 0.001 for homozygous with respect to OGG1 Ser326Cys, p = 0.007 for heterozygous and p = 0.001 for homozygous with respect to APE1 Asn148Glu). There was no significant difference in terms of PARP1 Val762Ala gene polymorphism between two groups.