While older radiologists faced increased risk of dying from radiation-related causes like cancer, those who graduated from medical school after 1940 do not face such risk any more.
The findings point to the success of efforts to reduce occupational radiation doses over the past several decades, the researchers said. "Most of the findings of increased risk were in the earlier radiologists," said study co-author Martha Linet, senior investigator at Radiation Epidemiology Branch at National Cancer Institute in the US.
‘Radiologists have lower death rates from all causes of death combined, compared to psychiatrists, and had similar risks of cancer deaths overall.’
"We do feel there is evidence that decreases in dose in the United States and other countries seem to have paid off, reducing risks in recent graduates," Linet noted. The study appeared online in the journal Radiology.
The study is based on records from the American Medical Association (AMA) Physician Masterfile, a database established in 1906 that has grown to include current and historical data for more than 1.4 million physicians, residents and medical students in the US. They compared cancer incidence and mortality rates between 43,763 radiologists and 64,990 psychiatrists who graduated from medical school between 1916 and 2006.
Psychiatrists were chosen as a comparison group because they are unlikely to have had occupational radiation exposure. Overall, male radiologists who graduated after 1940 had a better health profile than that of their psychiatrist colleagues. The death rate for radiologists from all causes was lower and there was no evidence of increased mortality from radiation-related causes such as cancer or cardiovascular disease.
"Our most important finding is that radiologists have lower death rates from all causes of death combined, compared to psychiatrists, and had similar risks of cancer deaths overall," Linet said. In contrast, radiologists who graduated before 1940 faced increased death rates from certain conditions, including acute myeloid leukemia and myelodysplastic syndrome, which are known to be related to occupational radiation exposure.
The reduced health risks for more recent radiology graduates are likely due to developments and improvements in radiation protection and monitoring, according to the researchers, along with improvements in equipment safety.