I recently received a question about whether I stand by my concerns over the new criteria for diagnosing Alzheimer’s disease (original article from April 2011). The short answer is yes. Alzheimer’s disease presents in three broad ways. The first is an early stage where there are no obvious symptoms but changes are already occurring in the brain. This is the stage targeted by the new diagnostic criteria. The idea is that the failure of treatments in clinical trials to date is that we wait too long to start taking the drugs as the brain is too damaged to benefit.

Successful treatment would delay or prevent progression to the next stage called Mild Cognitive Impairment where the problems are mild and there is no disability. Dementia is the third phase where changes are severe enough to cause loss of independence and disability.

The early phase is identified by the use of biomarkers such as brain scans and tests of cerebral spinal fluid are used to identify the early stages of Alzheimer’s disease and to start treatments. There are several serious flaws with this strategy. First, diagnosis would be made on the basis of amyloid proteins which are associated with the development of plaques – a theory of what causes Alzheimer’s disease. However, autopsy studies, up to 30% of people with dense amyloid plaques never develop clinical signs of Alzheimer’s disease. They would be misdiagnosed. Second, the most advanced clinical trial of amyloid reversing drugs was terminated by Lily last year. The drug reversed amyloid deposition but clients got worse rather than better. Third, how early should interventions start? Fourth, how safe is early intervention? Will there be unintended and damaging side effects of altering brain chemistry so early in life?

Furthermore, how will those with no clinical changes react to being given such a scary diagnosis? I have already had a number of clients who have seen me in a state of panic as a result of misdiagnosis and over diagnosis. They were living their life as if they would soon be demented and giving up when there is no need. Alzheimer’s disease is diagnosed by its course over time (usually many years). Not everyone who has memory decline will develop Alzheimer’s disease. Not everyone who has Alzheimer’s disease (or develops plaques) will become demented. Not everyone who becomes demented has Alzheimer’s disease

Reducing Alzheimer’s disease to molecular biology adds to the sense of fear and futility. We sit and wait for a medical cure. We already have excellent cognitive and memory tests that are not invasive and allow us to assess and monitor brain function just as we use blood tests to determine the functioning of thyroid, kidney, and liver. These tests are the gold standard but many in the medical community ignore their utility in diagnosis and tracking. Memory testing allows us to be proactive without inducing needless panic and hopelessness.
We would be better off putting more money and resources into life style interventions targeting middle life or earlier. For now, be proactive about your memory and protect your future. There is so much that can be done if the focus is on memory rather than Alzheimer’s disease.