Guidelines fail to curb use of CT, MRI for back pain

CT and MRI scans of the spine for back pain are the poster children for overused and likely inappropriate imaging. Throughout the 2000s the use of advanced imaging in this area increased significantly and presumably drove up downstream costs for back pain management, according to a study published online July 29 in JAMA Internal Medicine.

“Despite numerous published clinical guidelines, management of back pain has relied increasingly on guideline discordant care,” wrote John N. Mafi, MD, of Beth Israel Deaconess Medical Center, Boston, and colleagues. “Improvements in the management of spine-related disease represent an area of potential cost savings for the health care system with the potential for improving the quality of care.”

More than 10 percent of visits to a primary care physician (PCP) are related to back pain, amounting to more than $100 billion in direct and indirect costs combined, explained the authors. Guidelines discourage early imaging in most cases, but studies have suggested increasing rates of CT and MRI use.

Since many of these prior studies had become dated or were limited to specific populations, Mafi and colleagues set about characterizing the management of back pain using nationally representative data from the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey. They studied outpatient visits with a primary or secondary symptom of back or neck pain from January 1, 1999, through December 26, 2010. Final analysis excluded patients with neurologic symptoms, cancer or any of the other rare concomitant red flags that could indicate an appropriate use of imaging.

A total of 23,918 visits for spine problems were included in the study, and while the use of radiographs remained stable over the study period, the combined rate of CT and MRI utilization increased from 7.2 percent to 11.3 percent. This trend held true when adjusted for a number of factors, such as patient age, sex, race/ethnicity and region.

“[W]hen comparing visits with the patient’s self-identified PCP vs those with another health care professional, we found that non-PCPs were much more likely to order advanced imaging,” wrote the authors. “Presumably, this group includes those who perform procedures such as spinal surgery.”

Referrals for physical therapy remained unchanged at approximately 20 percent, but physician referrals increased from 6.8 percent to 14 percent over the study period.

Mafi and colleagues underscored the importance of the findings by noting that a previous study determined that the 2.2 million lumbar CTs performed in the U.S. in 2007 were projected to result in 1,200 additional future cancers. Meanwhile, early MRI for back pain has been associated with an 8-fold increased risk of surgery.

In addition to the findings regarding imaging, the study also revealed that the use of acetaminophen or nonsteroidal anti-inflammatory drugs fell from 36.9 percent to 24.5 percent over the course of the study, while guideline discordant use of narcotics increased from 19.3 percent to 29.1 percent.