Alzheimer’s Disease… Would You Really Want to Know?
If it was possible to predict that you are at higher risk of developing Alzheimer’s disease in 20 years time, would you really want to know? Researchers from the Washington University School of Medicine in St Louis have published an article in the journal “Neurology” where they believe they have been able to do just that with around a 94% accuracy.
Alzheimer’s disease is the most common form of dementia and the evidence clearly shows that is due to a combination of increasing sluggishness in the microcirculation of the brain and reduced clearance of accumulated toxic proteins. Every time you have a thought or emotion, a chemical reaction occurs within the brain and a waste product is created by the reaction. It’s a bit like having a meal and having to remove the scraps off your plate by washing the plate or using the dishwasher. These toxic proteins accumulate in over time because of defective clearance by the two mechanisms above. These toxic proteins are known as amyloid proteins and by measuring certain aspects of this in the blood stream and combining this with the person’s age and another well described Alzheimer’s associated protein known as APO E4, leads to this highly accurate prediction for Alzheimer’s disease 20 years before the diagnosis.
What's the risk?
Up to now, the gold standard has been the PET scan but it appears that this new blood test algorithm is even more accurate.
The study followed 158 adults older than 50 of which 148 were cognitively normal at the start of the study. The blood test and the PET scan agreed 88% of the time, but interestingly when the false positive blood tests were examined a few years later, the PET scan became abnormal.
In summary, if you are older than 65 there is double the risk for Alzheimer’s disease every 5 years. If your APO E4 is positive there is an increased risk for Alzheimer’s disease somewhere between 3-5 times and when these 2 factors are combined with the positive amyloid blood tests there is a 94% accurate prediction of Alzheimer’s disease.
Why would you want to know?
But, you may ask why would I want to live with the sword of Damocles poised well and truly above my head waiting to strike? The answer to this is very clear. At present, the current management for Alzheimer’s disease is quite poor and the prognosis is dreadful in almost all cases. But, there have been some very encouraging studies performed on new drugs in this area and in particular monoclonal antibodies have shown a stabilisation and even reversal in some cases.
Another drug-Anavex, in a small study of only 32 people performed in Melbourne showed significant reversal of the disease, not to mention studies of certain antidepressants and anti-inflammatories which have shown some benefit especially in laboratory animals and some early human work.
Professor David Smith at Oxford University performed the Optima trial of 271 people with mild cognitive impairment measuring MRI scans and neurocognitive testing at the start of the trial and 2 years later. This was a randomised, placebo controlled trial of high-dose Multivitamins, showing a 30% reduction in the progression to Alzheimer’s disease and in those patients with the highest homocysteine levels, a 50% reduction.
A recent study performed in the UK, known as the Whitehall 2 study, of just over 10,200 participants shows that maintaining high levels of social contact between the ages of 50-70 led to a significant reduction in progression to cognitive decline.
Dale Bredesen has written a book, the end of Alzheimer’s disease and also published a pilot study of his ENT program of 11 patients with varying degrees of Alzheimer’s disease. This study showed reversal of the disease in 10/11 cases by the use of lifestyle modification, neutraceuticals i.e. evidence based supplements, brain training and trans-cranial brain stimulation.
So, if you went ahead and had this blood test algorithm when it became available, and if it was positive, giving you the potential of developing Alzheimer’s disease and 20 years time, there is increasing evidence that there is so much you can do right now to prevent any progression to this horrible condition.
Also, with significant advances in modern medicine, it is highly likely that we will have very effective therapies for this condition over the next 5-10 years. So, would you want to know? I certainly would!
Providing stress echocardiography heart health services for more than 25 years, Dr Walker is an expert in the field of preventative cardiology and has published seven best-selling books about the subject. Dr Walker is a member of the Miskawaan Health Group medical advisory board.