Study on low-dose radiation and the risk of cardiovascular diseases published

Cardiovascular system Source: peterschreiber.media/Stock.adobe.com

Radiation, which is also used in radiation applications in medicine, increases the probability of cardiovascular diseases occurring – even at comparatively low doses. This is indicated by the findings of an extensive meta-study in which the Federal Office for Radiation Protection (BfS) also participated and which was published in the prestigious British Medical Journal. For example, these findings are relevant to occupational radiation protection or patients undergoing radiotherapy.

Correlation with high radiation exposure already known

An international team of researchers reviewed more than 15,000 studies on the risk of cardiovascular diseases following radiation exposure. Of these, 93 conclusive studies were evaluated in a meta-analysis. The results indicate a moderate but statistically significant increase in risk even at a dose of less than 500 milligrays (mGy) – which is considerably less than is used in radiotherapy.

"The link between ionising radiation and the risk of cardiovascular disease has long been known in research. However, the associated studies related to high doses of several grays", says co-author PD Dr Michaela Kreuzer, Head of the "Effects and Risks of Ionising and Non-Ionising Radiation" division at the BfS. "In recent years, there has been increasing evidence of an increased risk – even at considerably lower radiation doses. The results of the current meta-analysis clearly support this assumption."

The risk also increases in the low-dose range

CT scan Source: Johnny Greig via Getty Images

The studies included in the analysis cover a wide range of radiation exposures in different situations. These are data mainly from radiotherapy and occupational radiation exposure but also from radiological diagnostics.

The researchers concluded that the risk of cardiovascular disease increases with the radiation dose. Even when considering moderate doses of less than 500 mGy or low dose rates of less than 5 mGy per hour, there was still a correlation.

Nevertheless, the resulting risks for the population are rather low for most situations involving exposure to radiation. With a comparatively high radiation dose of 1 Gray, the additional absolute lifetime risk would be between 2 and 4%.

In the study, the authors conclude by emphasising the need for research in the moderate and low dose range. There is still too little is known about the underlying biological mechanisms of action in order to be able to better assess and evaluate the risks.