Early Imaging, Diagnosis of Alzheimer’s Leads to Better Outcomes for Patients in Early Stages of the Disease

The study, called Metabolic Cerebral Imaging in Incipient Dementia, is an ongoing US national clinical trial sponsored by the US Centers for Medicare and Medicaid Services (CMS; Washington DC, USA). These interim data revealed that patients whose physicians gathered data from a brain positron emission tomography (PET) imaging scan performed with the tracer fluorodeoxyglucose (FDG) did better over two years than those whose doctors were randomized to not have access to the scan information.

Study lead investigator Dr. Daniel Silverman, a University of California, Los Angeles (UCLA; USA) professor of molecular and medical pharmacology, said, “During the subsequent two years after their PET scans, these patients had superior executive function, better memory abilities and greater preservation of overall cognitive function, providing the first direct evidence that patients whose early Alzheimer’s disease is revealed by FDG-PET will do better than patients with the same condition, but with their brain metabolism pattern remaining unknown to their doctors and themselves.”

The findings from the study were presented September 26, 2013, at the Medical Biotech Forum, held in Shenzhen (China). US Medicare currently does not reimburse for PET scans for patients showing signs of persistent cognitive decline, but who do not yet have dementia, according to Dr. Silverman. By the time Medicare covers an FDG-PET scan, for which they reimburse roughly USD 1,200 per patient, a lot of impairment, some of it irreversible, has already been done to the brain tissue.

Medicare currently is reexamining reimbursement policies for PET scans obtained in dementia cases, specifically with respect to amyloid imaging. A US healthcare coverage decision is expected October 1, 2013, according to Dr. Silverman. Prior to the findings of the study being presented, there was no thoroughly controlled scientific data available that evaluated the long-term clinical advantages associated with obtaining a PET scan, or any other kind of neuroimaging, in the assessment of cognitively declining patients.

According to the investigators, this multicenter, prospective, randomized and blinded study demonstrates significant clinical benefit, which may also cost less healthcare dollars. “Patients who don’t have Alzheimer’s disease may be prescribed drugs that won’t help them, or even make them worse,” Dr. Silverman said.

An undiagnosed AD patient, furthermore, will not get drugs that the study is showing will help them maintain their cognitive abilities when administered earlier. This may lead to the need for nursing home care six to nine months earlier than for those with the same AD brain pattern, but who are diagnosed and treated sooner as a result of the early availability of the PET scan data. “With nursing home care costing an average of about USD 7,000 a month, there is the potential for CMS and American taxpayers to save several billion dollars per year,” Dr. Silverman said.

These interim findings included 63 patients who underwent FDG-PET and neuropsychologic testing at baseline. The doctors in the arm of the study who were able to view the PET scan immediately treated their patients differently than the physicians in the other arm, who did not get scan results until the end of the two-year study. Approximately 40% of the patients whose clinicians were informed of the presence of the AD brain metabolism pattern were given drugs specifically indicated for dementia within the first six months of the study.

Of the patients whose brain PET scans showed the Alzheimer metabolism patterns randomized to a two-year delay of release of their scan results, none were prescribed Alzheimer drugs in the first six months, and only 12% were prescribed those medications by the end of the first year, according to Dr. Silverman. “[…] This study provides the first direct evidence for improved cognitive outcomes attributable to a neuroimaging test of any kind.”

Related Links:
US Centers for Medicare and Medicaid Services
University of California, Los Angeles