In a commentary published online in JAMA Internal Medicine, Susan Molchan, M.D., a private practice psychiatrist from Bethesda, Md., suggested the push to get amyloid PET scans covered by Medicare is part of the "the latest campaign for overdiagnosis."
Molchan, who has conducted PET research and practiced nuclear medicine, referred to the most recent Alzheimer's Association International Conference in which a "late-breaking, special" session was put together to discuss the decision by the Centers for Medicare & Medicaid Services not to cover amyloid PET scans (except in limited situations).
"Many people were promoting the scans (price tag, $3,000 to $4,000) despite the lack of evidence that they did anything for patients," she wrote, adding that the scan doesn't establish a diagnosis of Alzheimer's disease or other cognitive disorder, but instead is used as part of a diagnostic evaluation.
Molchan goes on to quote JAMA Internal Medicine Editor Robert Steinbrook, M.D., who in an article in January wrote that "it would have been irresponsible for the CMS to cover amyloid PET imaging without adequate evidence about its role in AD or other neurodegenerative diseases."
In Molchan's view, a familiar cast of characters--pharmaceutical and imaging company executives, lobbyists, advocacy groups and foundations, and academics, some of whom are consultants for pharmaceutical companies--are identifying cognitively impaired elderly adults as a target for more scanning, while at the same time "brightening the visions of blockbuster drug sales to our growing senior population."
Ironically, she said, this is happening during a time when evidence is starting to accumulate that dementia rates are dropping. She pointed to a study published in the Lancet last July that found that over a 20-year period, dementia rates dropped by 24 percent, and wrote that this study, as well as others, shows the potential of deriving health benefits from focusing on risk factors associated with dementia, such as high blood pressure, diabetes, smoking, obesity, and physical inactivity.
"Impressive as scanning technologies are, positrons are unlikely to light the path to healthy brain aging," she said. "But the horizon is brightening with knowledge that we have right now."