In reading through Alzheimer's news yesterday, I found a study on twins with Alzheimer's which was very interesting because it looked at the brains of twins after they had passed. At least one twin of each pair had been diagnosed with Alzheimer's before their deaths. Not only had the twins shows similar progression of symptoms; their brains had similar damage.
The part that jumped out at me, however, was the opening sentence of the news release (linked above). It states, "Despite
widespread use of a single term, Alzheimer’s disease is actually a
diverse collection of diseases, symptoms and pathological changes." This stands out because it is the first time I've seen Alzheimer's referred to as more than a single disease.
If this is true, it may explain a number of things that have been previously noted about Alzheimer's and the people who have it. Why is it so hard to find the cause; not just an increased risk factor? Why have we been unable to devise a definitive test? Why have we been unable to develop an effective treatment or prophylactic? Why does the disease progress so differently from patient to patient? We recognize themes and variations on patterns seen with the patients, but my sister's experience will differ quite a bit from that of another person. It differs even from what we saw with my Grandmother.
Could it be that, perhaps, we've been wrong and we're really dealing with multiple diseases?