News | Radiology Imaging | September 03, 2019

Medical Imaging Rates Continue to Rise Despite Push to Reduce Their Use

Potential harms need to be considered before scanning, researchers conclude

Medical Imaging Rates Continue to Rise Despite Push to Reduce Their Use

September 3, 2019 — Despite a broad campaign among physician groups to reduce the amount of medical imaging, use rates of various scans have continued to increase in both the U.S. and Ontario, Canada, according to a new study. A recent reacceleration in the growth of imaging concerns researchers because it is widely believed to be overused. The study of more than 135 million imaging exams was conducted by researchers at UC Davis, UC San Francisco and Kaiser Permanente.

The study, published Sept. 3, 2019 in the Journal of the American Medical Association, is the first of its size to determine imaging rates across different populations.1 It found that although the growth in imaging slowed in the early 2000s, it ticked back up in recent years for computed tomography (CT) and magnetic resonance imaging (MRI) in most patient age groups. A notable exception was a decline in CT use in children in recent years.

CT scans use ionizing radiation to create images of the inside of the body, and they deliver a radiation dose far higher than a conventional X-ray, while MRIs use magnetic fields and radio waves to create images and do not expose patients to ionizing radiation. The authors noted that the study does not discuss whether the documented imaging use was appropriate or associated with better patient outcomes.

"Medical imaging is an important part of healthcare and contributes to accurate disease diagnosis and treatment, but it also can lead to patient harms such as incidental findings, overdiagnosis, anxiety and radiation exposure that is associated with an increased risk of cancer," said lead author Rebecca Smith-Bindman, M.D., a UCSF professor of radiology, epidemiology and biostatistics, and obstetrics and reproductive medicine and a member of the Philip R. Lee Institute of Health Policy Studies.

Although it is widely believed that imaging rates are declining due to payment and educational efforts that have targeted unnecessary imaging, the authors found a reacceleration in imaging use, with ongoing growth in the use of CT and MRI in adults.

"Like all aspects of medicine, it's important to make sure imaging is justified, and that the potential benefits are balanced against the potential harms," said Smith-Bindman. "These potential harms of false positive diagnoses and overdiagnoses can impact everyone who undergoes a test and thus need to be considered when imaging is used."

Diana Miglioretti, Ph.D., biostatistics professor at UC Davis Department of Public Health Sciences and senior author on the study, said there were some hopeful signs among the findings.

"The good news is that rates of CT imaging are starting to come down in children," Miglioretti said. "However, they're still far lower in Ontario than in the U.S., suggesting there is additional room for improvement. It's also important to reduce unnecessary imaging in adults given they are also at risk of radiation-induced cancers."

Watch the VIDEO: Age, Interval and Other Considerations for Breast Screening, an interview with Miglioretti

The researchers analyzed patterns of medical imaging between 2000 and 2016 among a diverse group of 16-21 million adult and pediatric patients enrolled in seven U.S. healthcare systems and in the universal, publicly funded healthcare system in Ontario, Canada. For the U.S. data, they included people receiving care in both fully integrated healthcare systems such as Kaiser Permanente, and systems with mixed insurance including HMOs and PPOs with fee-for-service plans.

"Our capture of medical imaging utilization across seven U.S. healthcare systems and Ontario, Canada, over a 16-year period provides one of the most comprehensive assessments to date of imaging in children to older adults in North America," said Marilyn Kwan, Ph.D., co-author and senior research scientist in the Kaiser Permanente Northern California Division of Research.

Among the findings:

  • Annual growth in CT, MRI and ultrasound were highest in earlier years (2000-2006), but utilization has continued to rise year over year; between 2012 and 2016 there has been 1-5 percent annual growth for most age groups and most tests in both the U.S. and Ontario;
  • The one exception was CT use in children, which declined in the U.S. from 2009 -2013 and remained stable since 2013 and declined in Ontario since 2006;
  • Rates of imaging with CT and MRI are higher in the U.S. than in Ontario, but that gap is closing. For example, among older adults in 2016, there were 51 MRIs per 1,000 patients in the U.S. and 32 per 1000 patients in Ontario;
  • Rates of imaging accelerated after initially dropping in many cases. For example, the rate of growth in CT scans among the elderly was 9.5 percent in 2000-2005, dropped to 0.9 percent in 2006-2011, but then increased to 3 percent annual growth over the last five years; and
  • Imaging rates for both adults and children were higher in the mixed model versus fully integrated healthcare systems, but the differences were modest.

The authors note that potential overuse of diagnostic testing has been addressed with the "Choosing Wisely" campaign launched in 2012 by the American Board of Internal Medicine Foundation and endorsed by 85 professional medical societies. The effort urges physicians to talk with their patients about whether an imaging study is necessary, free from harm and supported by evidence. Other initiatives, including by the federal Centers for Medicaid and Medicare Services, have created incentives to discourage overuse of imaging by reducing reimbursement rates for certain scans.

The study authors say their findings suggest that neither the financial incentives nor the campaign to reduce use of medical imaging have been entirely effective.

"Although most physicians are aware that imaging tests are frequently overused, there are not enough evidenced-based guidelines that rely on a careful consideration of the evidence, including information on benefits and harms that can inform their testing decisions," Smith-Bindman said. "In the absence of balanced evidence, the default decision is to image."

For more information: www.jamanetwork.com

Reference

1. Smith-Bindman R., Kwan M.L., Marlow E.C., et al. Trends in Use of Medical Imaging in US Health Care Systems and in Ontario, Canada, 2000-2016. Journal of the American Medical Association, published online Sept. 3, 2019. doi:10.1001/jama.2019.11456

Related Content

Nurse Practitioners, Physician Assistants Rarely Interpret Diagnostic Imaging Studies
News | Radiology Business | September 18, 2019
September 18, 2019 — Although Medicare claims data confirm the...
The Siemens Somatom Go.Sim computed tomography (CT) system for dedicated radiation therapy planning

The Siemens Somatom Go.Sim computed tomography (CT) system for dedicated radiation therapy planning. Image courtesy of Siemens Healthineers.

News | Computed Tomography (CT) | September 15, 2019
Siemens Healthineers debuted two computed tomography (CT) systems dedicated to radiation therapy (RT) planning at the...
Philips Showcases Integrated Radiation Oncology Portfolio at ASTRO 2019
News | Radiation Oncology | September 13, 2019
Philips will showcase its integrated radiation oncology portfolio at the American Society of Radiation Oncology (ASTRO...
Richardson Healthcare Receives CE Mark Approval for ALTA750 Canon/Toshiba CT Replacement Tube
News | Computed Tomography (CT) | September 11, 2019
Richardson Healthcare, a Division of Richardson Electronics Ltd., announced it has received CE Mark approval for the...
Bayer Introduces Medrad Stellant Flex CT Injection System
Technology | Contrast Media Injectors | September 11, 2019
Bayer announced the introduction of the Medrad Stellant Flex computed tomography (CT) injection system. Stellant Flex...
Imaging Biometrics and Medical College of Wisconsin Awarded NIH Grant
News | Neuro Imaging | September 09, 2019
Imaging Biometrics LLC (IB), in collaboration with the Medical College of Wisconsin (MCW), has received a $2.75 million...
ASNC Announces Multisocietal Cardiac Amyloidosis Imaging Consensus
News | Cardiac Imaging | September 09, 2019
September 9, 2019 — The American Society of Nuclear Cardiology (ASNC) published a new expert consensus document along
Scranton Gillette Communications Names Imaging Technology News Group Publisher and Integrated Media Consultant

Diane Vojcanin (left) was named vice president, group publisher, healthcare group, overseeing Imaging Technology News (ITN) and Diagnostic and Interventional Cardiology (DAIC). Andreja Slapsys (right) was named a healthcare group integrated media consultant.

News | Radiology Business | September 06, 2019
Business-to-business communications leader Scranton Gillette Communications has named Diane Vojcanin as vice president...
AJR Publishes Gender Affirmation Surgery Primer for Radiologists. transgender radiology images,

Scout image from contrast-enhanced CT shows erectile implant; stainless steel and silicone anchors (arrow) transfixed to pubic bone are asymmetric.

News | Orthopedic Imaging | September 05, 2019
September 5, 2019 — An ahead-of-print article published in the December issue of the American Journal of Roentgen
Sudhen Desai, M.D.

Sudhen Desai, M.D.

Feature | Pediatric Imaging | September 04, 2019 | By Jeff Zagoudis
Burnout has become a popular buzzword in today’s business world, meant to describe prolonged periods of stress in the