Between 2001 and 2010, there was a fourfold increase in emergency department use of CT scans to evaluate respiratory symptoms. And that increase is too much, according to researchers at the Geisel School of Medicine at Dartmouth College.
"Beyond the risk posed by ionizing radiation, high-resolution CT may have unintended downstream consequences related to incidental findings and overdiagnosis, leading to a costly and potentially harmful diagnostic, therapeutic or interventional cascade," wrote researchers Dr. Frank S. Drescher and Dr. Brenda E. Sirovich.
The team analyzed data collected from 2001 to 2010 in the National Hospital Ambulatory Medical Care Survey. In 2001, 2.2 percent of patients received a CT scan to evaluate respiratory symptoms. By 2010, 9.4 percent of patients were receiving scans. Results of the trend analysis were published in the Dec. 28 issue of JAMA Internal Medicine.
While the number of CT scans increased, the number of antibiotic prescriptions and hospital admissions did not go up. Rather, an increased percentage of patients were discharged without a diagnosis during the study period.
In an accompanying editorial, two doctors suggest the reason for increased CT scans is due to physicians' reliance on imaging for clinical diagnosis and management. Dr. Rebecca Smith-Bindman and Dr. Andrew B. Bindman from the University of California, San Francisco, wrote that while imaging can be vital for for accurate diagnoses and treatment plans, it is also expensive and increases patients' radiation exposure.
That's part of the reason the American Board of Internal Medicine Foundation created the Choosing Wisely campaign in 2012. The goal is to identify tests, treatments and procedures that are sometimes used inappropriately. For example, some tests are used preferentially under fee-for-service payment plans, even if the test isn't useful to the patient, Smith-Bindman and Bindman wrote in an editorial.
Incentivizing procedures has led to the Medicare Incentive Payment System, the editorialists wrote. The system "will soon place Medicare physicians at financial risk for their practice style" since it reimburses based on physician performance comparisons, they say.
The analysis by Drescher and Sirovich and similar work of others indicate the problem goes further than simply ordering unnecessary tests, the editorial writers say. The bigger problem lies in the variability of the safety of the tests performed, they argue.
For example, in the United States, patient who receive a myocardial perfusion imaging test receives radiation that's 20 percent higher than the same test performed in 64 other countries. The radiation exposure for CT scans also varies widely among locations.
"To date, much of the work in the Choosing Wisely campaign has been done within silos (individual management systems that do not operate with any other system). For example, the Imaging Wisely recommendations were developed within radiology," Smith-Bindman and Dr. Bindman wrote. "When it comes to medical imaging tests, it is time for physicians who order the tests to join together with radiologists and other physicians who perform imaging studies to form a consensus guided by patients' values about the pressing need to perform imaging tests more wisely."
