Areas of the country with the highest number of MRIs have the highest incidence of surgery for lower-back pain, despite the lack of evidence showing that the surgeries are beneficial, Stanford researchers reported today in the journal Health Affairs. Previous studies have shown that increased surgery rates for back pain don't improve patient outcomes, "so heading in this direction is concerning," said senior author Laurence C. Baker, a professor of health research and policy at the Stanford University School of Medicine.
Between 2000 and 2005, the availability of MRI scanners in the United States more than tripled, from 7.6 machines per 1 million persons to 26.6 per million. State-of-the-art scanners cost more than $2 million apiece, so scans are expensive--about $1,500 for one low-back scan. The increased use of the scanners and the growing number of surgeries that result from such scans are one component in the increase in healthcare costs, Baker said.
Baker and Jacqueline D. Baras, a medical student, obtained Medicare claim data from 1998 to 2005 for about 20% of patients with non-specific low-back pain and compared it with data on the availability of MRI scanners, as determined by IMV Ltd., a healthcare consulting firm that provides such data to the medical industry. They found that the number of scans for low-back pain and the number of resulting surgeries in each of the 318 Metropolitan Statistical Areas were directly proportional to the availability of scanners. About two-thirds of the scans, moreover, occurred in the first month after the onset of pain, despite clinical guidelines that recommend at least a one-month delay because of the large number of patients who spontaneously recover.
"The net result is increased risks of unnecessary surgery for patients and increased costs for everybody else," said Dr. John Birkmeyer, a professor of surgery at the University of Michigan who was not involved in the study.
-- Thomas H. Maugh II
A state-of-the-art MRI can cost $2 million.
Credit: Jim Cole / AP