12.28.2004
A Light in Alzheimer's Darkness
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The Lafsers near their home in LaQuinta, CA Los Angeles Times/photo: Orlando Sentinel
Early detection is ever more important and with time, will grow more important. MRI and PET scans offer a way to detect anomalies in people suspected of early memory loss. The research indicated below, and cognitive's own research, suggests that scanning be deployed earlier than it has been up to now. Still, the costs to administer PET or a less expensive MRI could add to topline healthcare expenses in the short-run, even if the outcome is eventually less costly for the healthcare system. Non-interventional methods also exist, such as MemCheck, which can offer assistance to individuals and practitioners in the form of monitoring over time and provide a very inexpensive, point-to-point system for managing and observing cognitive performance objectively over time.
Brain scans may reduce the guesswork involved in diagnosis, offering some patients and their families a chance to prepare.
By Shari Roan | Los Angeles Times
Posted December 28, 2004
For almost three years, Janelle Lafser pleaded with doctors to order a PET scan for her husband, Frank.
He had been experiencing memory and mood problems -- beginning at age 45 -- and was having trouble in his job as an executive at a paint company. The doctors said he was depressed, but Janelle was unconvinced.
She suspected Alzheimer's disease and wanted the positron emission tomography test because it can provide physical evidence of the disease.
Physicians steadfastly refused, telling her that Frank was too young to have Alzheimer's, which occurs mostly in people age 65 and older.
Finally, when his doctors recommended electric shock treatments for depression, Janelle made it contingent upon a PET scan that showed no abnormalities. Only then did the Lafsers, who live in La Quinta, Calif., get the scan. As Janelle suspected, Frank had Alzheimer's disease.
Until recently, PET scanning has been seldom used in the diagnosis and treatment of Alzheimer's, even though it is billed as "a window to the brain" and is the only test, other than an autopsy, to offer physical proof of the disease. At about $1,500 per exam, doctors have deemed it too expensive and too experimental, with many saying a scan would be of little practical benefit to a patient with an incurable disease.
But some families have increasingly countered that they need a specific diagnosis of Alzheimer's -- backed by a PET scan -- to ensure proper treatment and to plan for their loved ones' gradual deterioration.
Now, more of them will know what type of treatment to pursue. In October, Medicare announced that it would begin to pay for PET scans in some patients with signs of the disease, a move that is expected to lead to increased coverage by private insurers.
That move could be just the beginning. Many experts predict that, within the next decade, PET scanning also may be recommended for healthy people who lack symptoms but who are at high risk for developing the disease. Alzheimer's physicians and researchers say PET scanning will lead to better diagnoses in the short term and -- with other brain-imaging techniques and blood tests in development -- to preventive treatment of Alzheimer's in the long term.
"PET scanning is going to be a very powerful tool in the future," says Dr. Richard Powers, a trustee of the Alzheimer's Foundation of America and chief of the bureau of general psychiatry for the Alabama Department of Mental Health.
Alzheimer's disease is a progressive brain disorder that causes declines in memory, cognition and functioning.
About 10 percent of Americans older than 65 and half of all people older than 85 have the disease, according to the Alzheimer's Association. No one knows what causes Alzheimer's, although most researchers think there are genetic influences.
PET produces images of the brain's activity; most other imaging devices show only structures in the brain. During a scan, a radioactive substance is injected into the body and a scanner tracks the resulting signals. The procedure is considered extremely safe because only a small amount of radiation is required.
The majority of people with Alzheimer's disease don't undergo the scans, says Robert J. Schumacher, vice president of the western region for Molecular Imaging Corp., a major provider of PET services, based in San Diego. Most are diagnosed after a comprehensive work-up that essentially rules out other causes of dementia. This approach includes a physical exam, lab tests and extensive psychological and cognitive tests.
The traditional office assessment for Alzheimer's disease can take months or years and is less accurate than PET scanning, advocates of the scan say.
Widely accepted research shows that traditional methods diagnose Alzheimer's accurately only 60 percent to 70 percent of the time, said Dr. Daniel Silverman, director of the University of California, Los Angeles Alzheimer's Disease Center, Imaging Core. PET scanning, meanwhile, is about 91 percent accurate, he says.
Early warning system
In ruling that it would pay for PET scans for some people suspected of having Alzheimer's, the Centers for Medicare and Medicaid Services stopped short of endorsing the scans as a general diagnostic test for the disease. Instead, Medicare and Medicaid will cover the test only for those patients whose symptoms are not typical and who doctors think may have Alzheimer's disease or one of several other brain disorders known as fronto-temporal dementia.
But it's a significant first step, says Dr. William Bradley Jr., chairman of the department of radiology at the University of California, San Diego.
"If you can use diagnostic imaging equipment like PET earlier and either slow a disease or cure it altogether," he says, "that is going to save money in the long run."
Experts agree the best use for PET in the Alzheimer's arena is to help doctors figure out whether a patient has the disease when the standard work-up has not produced a clear answer.
But for many patients, Silverman says, an earlier diagnosis offers several advantages, such as the opportunity to take one of several medications for Alzheimer's disease. The drugs typically work better the earlier they are started.
"What the data show is that you not only make an accurate diagnosis, but you make that accurate diagnosis three years ahead of time," Silverman says.
Some leaders in the field suggest that PET scanning eventually could be used to follow the progression of the disease and assess whether medications are working. And, although current drugs can only do so much, an earlier diagnosis can help families plan for the future.
The Lafsers found Frank's diagnosis both devastating and a relief.
"Once we knew the answer, all of my anger went away," says Janelle. "I could love him and accept that this is where we're going now. For Frank, it was like a ton of bricks was lifted off his shoulders. He had been beating himself up about why he was acting this way."
Window to the brain
Researchers acknowledge they still have much to learn about PET scans and Alzheimer's disease.
The National Institute on Aging announced plans for a five-year study on how PET, MRI and biological markers, such as blood and cerebral spinal fluid, can be combined to measure the progression of mild cognitive impairment and Alzheimer's disease.
Other researchers are also studying how PET can be used to assess progression of the disease.
Still other doctors are studying families with a strong incidence of the disease to see whether PET scanning can reveal changes in the brain well before any symptoms occur. This knowledge could lead to drugs that disrupt the disease process, says Bill Thies of the Alzheimer's Association. And a few scientists are using different imaging agents to detect the development of amyloid plaques -- protein deposits that disrupt brain-cell function and that may be one of the primary causes of the disease.
All agree that people with Alzheimer's will increasingly benefit from technology that reveals --objectively -- what is happening in the brain.
"Now we have a way of following the disease," says UC San Diego's Bradley. "That will spur the development of additional drugs. We do have a chance to cure this disease in some way. But we need an accurate way of imaging it first."
