March 25, 2011

Priming the Pump

More bad news about dementia in America was released recently by the Alzheimer’s Association in its report, “Alzheimer’s Facts and Figures 2011.” Actually, this year’s report isn’t much different from last year’s except that the number of people with some form of dementia in the U.S. has gone from 5.3 million to 5.4 million. We’re on track to have between 11 and 16 million citizens with dementia by 2050, assuming there is no breakthrough in our ability to treat or prevent Alzheimer’s. And while many drugs are undergoing evaluation as treatment for this devastating brain disease, none has shown dramatic effectiveness. As the report states categorically, “No treatment is available to slow or stop the deterioration of brain cells in Alzheimer’s Disease.”

Americans spend an enormous amount of money on medical care for people with dementia: the total health care tab for 2011 is projected to reach $183 billion. We spend more on patients who have both heart disease and Alzheimer’s than on patients who have heart disease alone; the same is true for diabetes and a slew of other conditions. In part, this is because people with dementia tend to be older than their counterparts without the disease and are therefore likely to be sicker: according to some estimates, 43% of people 85 or older have dementia. But it also means that a great many people with Alzheimer’s disease undergo invasive, high tech medical treatment that they find frightening and painful. Not only can’t they understand the purpose of the treatment, but they might also not want intervention if they realized one of its main effects was to allow them to live long enough to develop more advanced dementia.

The one new part of this year’s report is the section on “early detection and diagnosis: benefit and challenges.” Early diagnosis has been championed by many authorities in the field, including the International Work Group for New Research Criteria for the Diagnosis of Alzheimer’s Disease. This group now recommends changing the diagnostic criteria for Alzheimer’s to include “biomarkers” (abnormal proteins found in the cerebrospinal fluid) or “imaging tests” (such as Positron Emission Tomography or PET scans). The section on early diagnosis in “Alzheimer’s Facts and Figures” enumerates a host of potential benefits—for example, the opportunity to plan for the future—but ignores the risks—such as generating anxiety in patients and families alike. The real reason for early diagnosis, as with other medical conditions, is to provide treatment which, when given early on, is more effective than if it is administered later. Unfortunately, the only treatment currently available is of hardly any benefit at all. As the report acknowledges, the 5 drugs approved by the FDA for use in Alzheimer’s “temporarily slow the worsening of symptoms for 6-12 months.” That’s the best we have—and only a minority of patients even experience this degree of benefit.

It is the chart listing “recent advances in use of biomarkers and brain images for diagnosis of dementia in living people” that reveals the real purpose of the growing emphasis on early diagnosis. To make the diagnosis early, we will need to use new tests for Alzheimer's. New tests mean greater profits for the manufacturers of those tests. Drug companies and device manufacturers are hungry for new markets and one of the biggest markets is older people at risk for Alzheimer’s disease. From the manufacturers’ perspective, screening and diagnosis are even better areas for investment than treatment because the number of people in whom such testing might be done is orders of magnitude larger. Everyone over 65 could be a candidate for a screening test—currently 39 million people in the U.S. And of course, if the test is negative, it will need to be repeated a few years later. We’ve already seen efforts to expand the use of expensive diagnostic tests for Alzheimer’s disease: the manufacturers of the PET scan, a sophisticated imaging device, have long been in search of new uses for their technology. While it is now widely used to follow the progression of disease in cancer patients, it was also advocated to diagnose Alzheimer’s disease. When the manufacturer sought approval from the Centers for Medicaid and Medicare Services for reimbursement of the scan in 2003, CMS turned down the request. There was simply no compelling evidence that PET scans are useful to diagnose Alzheimer’s. The companies who made PET scans were not pleased. One of the co-founders of the largest manufacturer (and a board member and major shareholder), happened to be friends with Ted Stevens, the Senator who was then head of the appropriations committee that controlled the purse strings of CMS. The upshot was that although there wasn’t a shred of new evidence suggesting that PET scans are important in the diagnosis of Alzheimer’s, the test was approved for Medicare coverage (ostensibly only if the goal is to distinguish Alzheimer’s disease from another far less common cause of dementia, fronto-temporal dementia).

Pharmaceutical companies like the idea of early diagnosis, too, because they want to be able to swoop in and offer a drug, however limited its benefit, to anyone who tests positive. The world’s largest drug company, Pfizer, lists six “Invest to Win” areas in its 2009 Annual Report. Number one on the list is Alzheimer’s disease. Now there’s nothing wrong with wanting to find a treatment for Alzheimer’s disease; on the contrary, it would be wonderful. And maybe one of the drugs that Pfizer is testing will turn out, against all the current evidence, to be truly beneficial. But at this point in time, the main purpose of early diagnosis is to have a ready market for whatever drugs emerge from the Pfizer pipeline, however minimal their effectiveness.

One day, when we have a drug that can stop the accumulation of the plaques and tangles that characterize Alzheimer’s disease in their tracks, early diagnosis will be important. In the meantime, relax and enjoy yourself. Do not rush out to have a lumbar puncture for the purpose of measuring “markers” for Alzheimer’s in the cerebrospinal fluid; do not succumb to pressure to have a PET scan. Occasionally, ignorance really is bliss.

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