Reproductive outcomes and Y chromosome instability in radiation-exposed male workers in cardiac catheterization laboratory

Occupational Risks of Radiation Exposure to Cardiologists

PURPOSE OF REVIEW

Invasive cardiologists are exposed to large amounts of ionizing radiation. This review aims to summarize the main occupational risks in a radiation-exposed cardiology practice.

RECENT FINDINGS

We carried out a literature review on the subject. The studies reviewed allowed us to list six main health risk categories possibly associated with radiation exposure among cardiologists: deoxyribonucleic acid (DNA) and biochemical damages; cancers; ocular manifestations; olfaction, vascular, and neuropsychological alterations; musculoskeletal problems; and reproductive risks. Our descriptive analysis demonstrates higher risks of DNA damage and lens opacities among radiation-exposed cardiology staff. Surveys and questionnaires have demonstrated a higher risk of musculoskeletal disease in exposed workers. Studies reported no difference in cancer frequency between radiation-exposed workers and controls. Changes in olfactory performance, neuropsychological aspects, and vascular changes have also been reported. Limited literature supports the security of continuing radiation-exposed work during pregnancy. Therefore, there is an urgent need to increase knowledge of the occupational risks of radiation exposure and to adopt technologies to reduce them.

Intergenerational effects of ionizing radiation: review of recent studies from human data (2018-2021)

PURPOSE

The purpose of this paper was to conduct a review of the studies published between 2018 and 2022 to investigate radiation-related effects in the offspring of human individuals exposed to ionizing radiation.

METHODS

The search identified 807 publications, from which 9 studies were selected for detailed analysis to examine for effects in children whose parents were exposed to various types and doses of radiation.

RESULTS

The review does not yield substantial evidence supporting intergenerational effects of radiation exposure in humans. However, caution is required when interpreting the results due to limitations in the majority of the published articles.

CONCLUSION

This review, covering the period 2018-2022, serves as an extension of the previous systematic review conducted by Stephens et al. (2024), which encompassed the years 1988-2018. Together, these two papers offer a comprehensive overview of the available evidence regarding the intergenerational effects of parental pre-conceptional exposure to ionizing radiation. Overall, the findings do not provide strong evidence supporting a significant association between adverse (or other) outcomes in unexposed children and parental preconception radiation exposure.

Radiation protection for healthcare professionals working in catheterisation laboratories during pregnancy: a statement of the European Association of Percutaneous Cardiovascular Interventions (EAPCI) in collaboration with the European Heart Rhythm Association (EHRA), the European Association of Cardiovascular Imaging (EACVI), the ESC Regulatory Affairs Committee and Women as One

The European Association of Percutaneous Cardiovascular Interventions (EAPCI), the European Heart Rhythm Association (EHRA), the European Association of Cardiovascular Imaging (EACVI), the European Society of Cardiology (ESC) Regulatory Affairs Committee and Women as One support continuous review and improvement, not only in the practice of assuring patients a high quality of care but also in providing health professionals with support documents to help them in their career and enhance gender equity. Recent surveys have revealed that radiation exposure is commonly reported as the primary barrier for women pursuing a career in interventional cardiology or cardiac electrophysiology (EP). The fear of foetal exposure to radiation during pregnancy may lead to a prolonged interruption in their career. Accordingly, this joint statement aims to provide a clear statement on radiation risk and the existing data on the experience of radiation-exposed cardiologists who continue to work in catheterisation laboratories (cath labs) throughout their pregnancies. In order to reduce the barrier preventing women from accessing these careers, increased knowledge in the community is warranted. Finally, by going beyond simple observations and review of the literature, our document suggests proposals for improving workplace safety and for encouraging equity.

Risk of ionizing radiation in pregnancy: just a myth or a real concern?

There are natural concerns regarding the risks posed to the foetus by ionizing radiation exposure during pregnancy. Therefore, many female physicians select to avoid working in an environment associated with ionizing radiation exposure like the catheterization laboratory and even exclude training as electrophysiology, interventional cardiologists, or radiologists. For those already working in this field, pregnancy involves usually a 1-year interruption (pregnancy and maternity leave) to their careers, leading at times to delays in the decision to become pregnant. This review describes the low added risk of malformation/cancer in the offspring, highlight gaps in our understanding, discuss several common wrong beliefs, and recommend how to further decrease radiation dose, especially during pregnancy.

Low-dose ionizing radiation and adverse birth outcomes: a systematic review and meta-analysis

OBJECTIVE

Ionizing radiation is a human carcinogen, and there is evidence that exposure to low-dose ionizing radiation increases the risk of adverse birth outcomes.

METHODS

We undertook a systematic review and meta-analysis to synthesize the research of maternal and paternal exposure to low-dose radiation on low birth weight, miscarriage, pre-term delivery, and stillbirth. Our literature search used four databases (PubMed, Environmental Index, GeoBASE, and the Cumulative Index to Nursing and Allied Health Literature). We included study populations exposed to occupational and medical sources of radiation, nuclear disasters, and those living near nuclear power plants. We considered papers published between January 1st, 1990, and June 30th, 2021. The quality of the studies was assessed, and we performed meta-analysis using random effects models to generate summary measures of association. Forest plots were created to assess the heterogeneity in these measures, and funnel plots were used to assess publication bias.

RESULTS

Overall, 26 studies were identified, and these yielded measures of association from 10, 11, and 8 studies for low birth weight, miscarriage, and stillbirth outcomes, respectively. It was not possible to perform meta-analyses for pre-term delivery due to a small number of studies. The meta-analysis summary relative risk (RR) of having a low-birth-weight infant among those ever exposed to radiation relative to those unexposed, after adjusting for publication bias, was 1.29 (95% CI 0.97-1.73). The corresponding risk estimates for miscarriage and stillbirth were 1.15 (95% CI 1.02-1.30), and 1.19 (95% CI 0.98-1.45), respectively.

CONCLUSIONS

Our findings suggest that ionizing radiation increases the risk of adverse birth outcomes. Future work should strive to provide data needed to better understand the shape of the exposure-response curve.

Low-dose radiation-induced demethylation of 3β-HSD participated in the regulation of testosterone content

The effects of low-dose radiation (LDR, ≤0.1 Gy) on living organisms have been the hot areas of radiation biology but do not reach a definitive conclusion yet. So far, few studies have adequately accounted for the male reproductive system responses to LDR, particularly the regulation of testosterone content. Hence, this study was designed to evaluate the effects of LDR on Leydig cells and testicular tissue, especially the ability to synthesize testosterone. We found that less than 0.2-Gy ⁶⁰ Co gamma rays did not cause significant changes in the hemogram index and the body weight; also, pathological examination did not find obvious structural alterations in testis, epididymis, and other radiation-sensitive organs. Consistently, the results from in vitro showed that only more than 0.5-Gy gamma rays could induce remarkable DNA damage, cycle arrest, and apoptosis. Notably, LDR disturbed the contents of testosterone in mice serums and culture supernatants of TM3 cells and dose dependently increased the expression of 3β-HSD. After cotreatment with trilostane (Tril), the inhibitor of 3β-HSD, increased testosterone could be partially reversed. Besides, DNA damage repair-related enzymes, including DNMT1, DNMT3B, and Sirt1, were increased in irradiated TM3 cells, accompanying by evident demethylation in the gene body of 3β-HSD. In conclusion, our results strongly suggest that LDR could induce obvious perturbation in the synthesis of testosterone without causing organic damage, during which DNA demethylation modification of 3β-HSD might play a crucial role and would be a potential target to prevent LDR-induced male reproductive damage.

Biomarkers of Genotoxicity in Medical Workers Exposed to Low-Dose Ionizing Radiation: Systematic Review and Meta-Analyses

Medical staff represent the largest group of workers occupationally exposed to ionizing radiation (IR). Chronic exposure to low-dose IR may result in DNA damage and genotoxicity associated with increased risk of cancer. This review aims to identify the genotoxicity biomarkers that are the most elevated in IR-exposed vs. unexposed health workers. A systematic review of the literature was performed to retrieve relevant studies with various biomarkers of genotoxicity. Subsequent meta-analyses produced a pooled effect size for several endpoints. The search procedure yielded 65 studies. Chromosome aberrations (CA) and micronuclei (MN) frequencies were significantly different between IR-exposed and unexposed workers (θ_pooled = 3.19, 95% CI 1.46–4.93; and θ_pooled = 1.41, 95% CI 0.97–1.86, for total aberrant cells and MN frequencies, respectively), which was not the case for ring chromosomes and nucleoplasmic bridges. Although less frequently used, stable translocations, sister chromatid exchanges (SCE) and comet assay endpoints were also statistically different between IR-exposed and unexposed workers. This review confirms the relevance of CA and MN as genotoxicity biomarkers that are consistently elevated in IR-exposed vs. unexposed workers. Other endpoints are strong candidates but require further studies to validate their usefulness. The integration of the identified biomarkers in future prospective epidemiological studies is encouraged.