Health Care Workers' Radiation Exposure Related to Range of Health Problems

April 12, 2016—The American Heart Association (AHA) announced the publication of a study showing that health care workers performing fluoroscopic x-ray–guided cardiovascular procedures in cardiac catheterization labs (CCLs) may be at higher risk than workers elsewhere for health problems including cataracts, skin lesions, cancers, and orthopedic illness. The study by Maria Grazia Andreassi, MSc, PhD, et al is available online ahead of print in Circulation: Cardiovascular Interventions.

The new findings are based on an Italian survey answered by 466 workers who had an average of 10 years experience working in CCLs, plus 280 professionals who worked in other settings. Findings were adjusted for the fact that the CCL workers were more likely to be smokers, as well as other relevant factors.

Intensive training in radiation protection can reduce occupational doses dramatically, and every effort should be made to raise radiation awareness in the professional communities of interventional cardiologists and electrophysiologists.

In the AHA announcement, Dr. Andreassi commented, “Unfortunately, cardiologists pay little heed to monthly or cumulative reports of radiation exposure. And recent studies confirm that simple, effective protection measures—such as a lead curtain, protection glasses, and thyroid collars—are not used by the majority of exposed cardiologists.”

Dr. Andreassi continued, “For experienced, busy interventional cardiologists and electrophysiologists, annual exposure to radiation is around 5 mSv.” That amount adds up to 50 to 200 mSv, or the equivalent of 2,500 to 10,000 chest x-rays, over a 30-year career. Dr. Andreassi is Head of the Genetics and Molecular Epidemiology Unit at the National Research Council Institute of Clinical Physiology in Pisa, Italy.

Compared to health care professionals who are not exposed to radiation, CCL workers (including doctors, nurses, and technicians) who were exposed to radiation for a median of 10 years had 2.8 times higher odds of having skin lesion, 7.1 times higher odds of having orthopedic (back/neck/knee) problems, and 6.3 times higher odds of having cataracts.

The study showed that among CCL workers, estimated radiation exposure was highest for the interventional cardiologists and electrophysiologists. The odds of having medical problems also increased for workers with more than 16 years of history in the CCL. After adjusting for age, sex, and smoking status, workers with more than 16 years of history in the CCL also had three times high odds of having cancer. The study also found that CCL workers also had elevated rates of high blood pressure and high cholesterol, but relatively low rates of cardiovascular illness. However, previous epidemiological studies have linked chronic radiation exposure with long-term cardiovascular effects, stated Dr. Andreassi.

Dr. Andreassi added, “Occupational doses of radiation in cardiovascular procedures guided by fluoroscopy are the highest doses registered among medical staff using x-rays. Interventional cardiologists and electrophysiologists have a two to three times higher annual exposure than that of radiologists, as they are closer to the radiological source and experience radiation exposure with the patient, whereas diagnostic radiologists are generally shielded from radiation exposure.”

The AHA press release stated that study limitations noted by the investigators included the fact that survey respondents themselves chose whether to participate (and if they had health problems, may have been more motivated to do so) and radiation doses were self-reported, not directly measured. A direct cause-and-effect link between radiation exposure and health problems cannot be inferred from the results of this study.