MDC says, CT Scan Rates Tripled at HMOs in the Last 15 Years, Doubling Radiation Exposure to Patients.
Another major study is pointing to significant increases in radiation exposure from the growing use of medical imaging tests such as CT scans.
For the latest study, which is published in the Journal of the American Medical Association, researchers combed through the medical records of millions of patients enrolled in six large HMOs around the U.S. They found that the percentages of patients who received high or very high doses of radiation from medical imaging tests roughly doubled over the last 15 years.
Researchers say the increases in radiation exposures seen in the new study were driven by a sharp uptick in the number of CT scans ordered for patients.
From 1996 to 2010, CT scan rates tripled at the HMOs, rising from 52 per 1,000 patients to 149 for every 1,000 patients.
CT scans expose people to radiation doses that are 50 to 500 times higher than the dose delivered by a typical chest X-ray.
Though radiologists sometimes use higher doses of radiation to get a clearer image, Smith-Bindman says doses have escalated beyond the range that’s needed for image clarity. “The doses are so much higher than they need to be,” she says.
And researchers say that they found some evidence that testing was being ordered when it might not be needed.
“We know that in a lot of the cases, the CT really isn’t necessary and maybe you can wait. Or if the CT is necessary, then maybe you can just go lower dose,” Diana L. Miglioretti, PhD, tells WebMD. She is a senior investigator and biostatistician at the Group Health Research Institute in Seattle.
Miglioretti says the doses of radiation they documented in the study were chilling when viewed in the light of the risks of brain tumors and leukemia documented in the recent Lancet paper.
Assuming typical average doses for CT scans, The Lancet study found that having two to three CT scans of the head before age 15 exposed children to radiation levels that could triple a child’s risk of having a brain tumor.
By 2010, 2.5% of patients at HMOs received high annual doses of radiation from CT scans, up from 1.2% in 1996. Similarly, the number of patients who got very high doses of radiation from CT scans jumped from 0.6% to 1.4% in the same period. A high dose was anything between 20 and 50 millisieverts (mSv). A very high dose was over 50 mSv.
MDC says, remember-YOU are the patient. You can eliminate the doctors tests for your own safety. Don’t be a test monkey.