You’ve got an annoying niggle in your back. You’ve explored some of the surprising causes of back pain, but you’re still suffering. You visit your doctor who recommends a CT scan. May as well, right? Well actually, the answer may surprise you. New research published in the International Journal of Radiation Biology has uncovered some disturbing evidence that repeated X-rays or CT scans can affect your heart health.
Scientists already knew that exposure to high levels of ionizing radiation (such as that used in X-rays and CT scans), can cause damage to the cardiovascular system and threaten the efficient functioning of the heart. But this study has discovered that even low levels can damage your blood vessels, and the effects may only kick in several years after you’ve had your scan.
Omid Azimzadeh, PhD, and Soile Tapio, PhD, at the Helmholtz Zentrum München, German Research Center for Environmental Health, worked with colleagues to investigate the way low doses of radiation impact the cells in the coronary artery. They discovered that exposure to even a small dose (0.5Gy – equivalent to several CT scans), caused permanent changes to the endothelial cells in the lining of the coronary artery. This affects the ability of the artery to do its job.
The researchers found three important ways that exposure to ionizing radiation affected these endothelial cells:
Firstly, the cells produced lowered levels of nitric oxide. Nitric oxide is a compound that’s essential to several processes in the artery, including its ability to contract. Lower nitric oxide levels mean that the artery can’t pump blood around the body as efficiently, so the heart has to work much harder.
The damaged cells in the artery also produced increased amounts of reactive oxygen species (ROS). This ROS interferes with the way cells ‘talk’ to each other (cell signalling), causing damage to the body’s proteins and DNA.
And if that’s not enough, radiation also caused the endothelial cells to age prematurely, affecting their ability to function properly. This was only observed some time after the initial exposure—one or two weeks later in the lab—which equates to several years in the human body.
All these discoveries add up to changes that indicate a long-term impact on the health of the cardiovascular system and the heart.
So what should you do if your doctor recommends an X-ray or CT scan? Of course, if you have an urgent or serious problem, the choice is easy—get the screen. But if a scan isn’t essential, discuss alternatives with your physician. Maybe starting with physiotherapy treatment for back pain is a better solution than rushing into scheduling an unnecessary imaging.