Medicare Compliance & Reimbursement

With evidence limited on effectiveness, coverage too will be limited.

The Centers for Medicare & Medicaid Services announced a National Coverage Decision Sept. 16 extending Medicare coverage for positron emission tomography to some beneficiaries with signs of dementia.

Beneficiaries who meet diagnostic criteria for both Alzheimer's and fronto-temporal dementia but for whom evaluations for specific alternate causes of the dementia have produced no clinical answer are now covered for a PET scan to determine whether they suffer from Alzheimer's.

CMS recognizes that PET also may be useful for patients in the early stages of dementia, both as a diagnostic tool and as an aid to physicians in managing their cases, said Administrator Mark McClellan in a statement. However, evidence is still limited on that point, he noted. Therefore, for now, Medicare will pay for PET scans for other beneficiaries at risk for Alzheimer's only if they enroll in a large, CMS-approved "practical" clinical trial. Medicare also would pay other routine medical expenses for beneficiaries enrolled in such a trial, according to a CMS spokesperson.

Such a trial is not yet available but is under development, with a National Institutes of Aging spokesperson willing to say only that there will be an announcement "soon."

CMS spokespersons are careful to say that NIA will conduct the trial and that CMS didn't even attend an early September meeting about the study. However, the agency's Sept. 16 press release described the projected trial as "practical" as well as "large and easily accessible," indicating that the study will be part of a new breed of trials, specifically designed to produce results of immediate significance to policymakers.

A practical clinical trial of PET in Alzheimer's would be one of the first such studies conducted by the federal government and could herald a new era of collaboration among the government's pure research arm, the National Institutes of Health, and its clinical- and coverage-oriented agencies. Besides NIA and CMS, the Agency for Healthcare Research and Quality has participated in discussions of the Alzheimer's project.

Practical - or pragmatic - trials are clinical studies "for which the hypothesis and study design are developed specifically to answer the questions faced by decision makers." So runs the Journal of the American Medical Association's abstract of a Sept. 24, 2003, paper by ARHQ chief Carolyn Clancy, MD, and Sean Tunis, MD, chief of CMS's Office of Clinical Standards and Quality.

PCTs "address practical questions about the risks, benefits and costs of an intervention as they would occur in routine clinical practice," wrote Clancy and Tunis. They're distinguished from the most common form of clinical research - explanatory trials - by several characteristics, including that they "include a diverse population of study participants, recruit participants from a variety of practice settings and collect data on a broad range of health outcomes."

PCTs are expensive, and, so far, have been few in the United States.