Use of advanced radiology to assess injuries increased about threefold over 10 years in emergency rooms in the U.S., raising costs and possibly adding to cancer risk, researchers said.
About 15 percent of the 6,567 patients with injuries who came to emergency departments in 2007 in cases surveyed by the researchers received computerized tomography or magnetic resonance imaging scans, according to the study from Johns Hopkins University in Baltimore. That compared with about 6 percent of 5,237 in 1998, the researchers said today in the Journal of the American Medical Association.
Increased use of CT scans is linked with higher health-care costs, longer emergency-room stays and more radiation exposure, which may lead to cancer, the authors wrote. Future research should determine why CT scan use is rising and how to target imaging to those most in need, according to the article.
“We need to be smarter about imaging and we need to really look at the clinical situation and ask the question, ‘Does this patient really need the study?’” said David Waldman, chairman of the Department of Imaging Sciences at the University of Rochester Medical Center, in Rochester, New York, who wasn’t involved in the study. “Just because it’s easy now to get a CT scan doesn’t mean it’s the right thing to do.”
CT scans provide more details than a traditional X-ray. The scanners are made by Fairfield, Connecticut-based General Electric Co., Tokyo-based Toshiba Corp., Munich-based Siemens AG, and Amsterdam-based Royal Philips Electronics NV.
Annual spending on CT imaging more than doubled to $2.17 billion by 2007 from $975 million in 2000, according to a U.S. Government Accountability Office report cited by the study’s authors.
The researchers in the study used data from the National Hospital Ambulatory Medical Care Survey to determine trends in the use of radiology during emergency department visits from 1998 to 2007.
The scientists reviewed the cases of 65,376 people treated for injuries from events such as falls and car accidents. The cases were deemed representative of an estimated average of 22.4 million injury-related visits to emergency rooms each year.
Patients were 3.43 times more likely to receive a CT scan or MRI in 2007 than those in 1998, according to the study.
The percentage of patients diagnosed with life-threatening conditions, such as cervical spine fractures, was 2 percent in 2007 compared with 1.7 percent in 1998. Almost no change was seen in the proportion of hospital admissions for these patients, the study showed.
Message for Public
“Using CT and MRI scans comes at a cost and the cost is financial,” Frederick Kofi Korley, the lead study author and an assistant professor of emergency medicine at Johns Hopkins, said in a telephone interview on Oct. 1. “For the general public the message is, a scan is not always absolutely necessary.”
Health-care spending was $1.1 trillion in 1998, or an average of $4,094 a person and representing 13.5 percent of the gross domestic product, according to the U.S. Department of Health and Human Services.
In 2007, health-care spending was $2.2 trillion, or $7,421 a person, and represented 16.2 percent of GDP, the department reported.
Among the reasons CT scan use may be rising are that more patients ask for the tests, doctors feel they may gain more diagnostic information, more emergency departments have the scanners, and doctors may fear being sued for failing to use the technology, said Rita Redberg, a professor of medicine at the University of California, San Francisco.
A December study in the Archives of Internal Medicine found that radiation from CT scans may cause cancer decades later. A second study at the same time showed that radiation doses from CT scans vary and are higher than previously thought.
Redberg, an editor of the Archives who wrote an editorial accompanying the December studies, said she wants to see data to assess whether the use of CT scans has declined this year.
“I’m hoping in the last few months there have been some more thoughtful use of CT scans,” Redberg said in a telephone interview on Oct. 1.