Looking Back on 2011 Alzheimer's Research: Are We Stuck In a Rut?
As the year comes to a close it's tempting to look back and consider the progress (or lack of) that has been made with regard to the understanding and treatment of Alzheimer's disease.
Every so often something occurs that makes me sit up and pay attention. For example, the line we usually trot out about the risk for Alzheimer's disease is that aging is the single biggest risk factor. This is based on the sound observation that beyond the age of 65 the risk of Alzheimer's increases dramatically. By the age of 80, around 40 per cent of people have the disease.
With such evidence at our disposal it seems self-evident that the answer to the Alzheimer's puzzle exists somewhere in understanding the aging process. This leaves us with a couple of questions. Is Alzheimer's something that occurs as a natural process of aging or is it something that reveals itself as an unrelated biological process? At the moment most experts don't seem to view dementia and aging as separate processes, but might this in part be due to the fact that relatively few risk factors beyond aging have yet been controlled for?
Here's a case in point. In 2008 a study by The Salk Institute into the link between diabetes and Alzheimer's showed that people with diabetes have a 30 to 60 per cent higher risk of developing Alzheimer's than non-diabetics. The risk applies equally to diabetes 1 and 2, which might suggest blood glucose levels in the brain are implicated? When the research team tried tackling the reasons for this they concluded that vascular damage was due to oxidative damage to cells lining the brain's blood vessels. Put another way, we all have low levels of amyloid circulating in our blood, but do the high levels of glucose in diabetics react with amyloid to create some toxic mix?
Alright, so it doesn't solve the Alzheimer's question, but perhaps it does no harm to remind ourselves that our understanding of dementia isn't actually that good and we shouldn't get too comfortable falling back on explanations simply because they appear self-evident. In the days when plague ravaged the streets it was ‘self-evident' that the smells from decay and open sewers - the miasmas - were to blame.
Research is a painstaking processes that builds from the knowledge of previous successes and errors. It leaves me with another question. Are we fishing in a big pool with a single line, or should we be casting a net?