Alzheimer's discernible years before the outbreak

Alzheimer's: reduction of brain substance years before the onset of disease

15.04.2011

Alzheimer's disease can be seen in years before the outbreak of disease in a reduction in brain tissue in certain brain areas, report US scientists at Harvard Medical School / Boston, the Massachusetts General Hospital / Boston and the Rush University Medical Center / Chicago in the journal „Neurology“.

Alzheimer's disease, the most common form of dementia, would have been detected just over a decade before the onset of disease, Bradford Dickerson of Harvard Medical School and colleagues said. For the investigations of the US researchers have shown that the reduced brain matter in certain brain regions, a threefold higher risk of Alzheimer's disease is due. Thus, the brain substance can be regarded as a marker for the future Alzheimer's risk of those affected, said the US scientists.

MRI scans to detect brain matter
As part of their Alzheimer's study, the US researchers had examined around 60 people and accompanied them over a period of seven to eleven years. Only persons over the age of 70 who did not suffer from memory impairment at the beginning of the study and had no other signs of Alzheimer's disease were allowed to participate. A group of 33 subjects was followed for eleven years, a second group of 32 participants averaged seven years. In the first group, eight participants developed Alzheimer's disease, while in the second group, seven developed symptoms. The US researchers had as part of their study with the magnetic resonance imaging (MRI) images of the brain made to determine possible connections with future Alzheimer's disease of the study participants. The US researchers focused their MRI studies on certain brain regions, which were already linked to Alzheimer's in previous studies. Based on the MRI images, Bradford Dickerson and colleagues were then able to determine the size or mass of the crucial brain regions.

Relationship between size of brain mass and Alzheimer's
In the coming years of their Alzheimer's study, the US researchers found that there is an association between the size of certain brain structures (eg hippocampus) and the risk of Alzheimer's disease. Six out of eleven study participants (55 percent) who had particularly small brain structures on the MRI images were diagnosed with Alzheimer's during the course of the study. Of the nine study participants with the largest brain mass in the corresponding brain regions, none have developed Alzheimer's disease. Of the study participants with average brain substance, 20 percent had Alzheimer's symptoms, the US researchers report. However, the study participants with very small brain structures are not only particularly often affected by Alzheimer's, but the neurodegenerative disease also occurred much faster in them than in the other study participants, the scientists said.

New diagnostic procedures for early Alzheimer's disease detection?
Based on their current results, the US researchers hope to be able to determine the individual Alzheimer risk of patients in the future by MRI measurements of the brain substance. However, all previous results „preliminary results that can not yet be applied outside of trials“, Explained study author Bradford Dickerson. However, the US researchers were optimistic soon to be able to use the size of certain areas of the brain as a marker for possible Alzheimer's. With the development of a corresponding diagnostic procedure, the neurodegenerative disease could henceforth be detected much earlier than previously, which, according to the experts, would be particularly important for those affected. For a cure of Alzheimer's is not possible on the basis of the current state of medical research, but a delay in the course of the disease. Thus, with appropriate early diagnosis for the benefit of patients could still be gained several years in which they remain everyday, said the US scientists.

Massive increase in dementia and Alzheimer's
The results of US researchers on early detection of Alzheimer's disease are of particular importance against the background of current developments in the industrial nations. Because the number of Alzheimer's and dementia diseases is expected to rise massively in the coming years as a result of demographic change. According to the German Alzheimer's Association, around 1.2 million people in Germany already suffer from dementia today, with two-thirds of patients having Alzheimer's disease. However, the forecasts paint a rather bleak picture: According to the experts, the number of those affected will double by 2050. New methods of early detection could be extremely helpful in initiating appropriate countermeasures for individual patients. (Fp)

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Alzheimer's not curable
Dementia and Alzheimer's
New vaccine can stop Alzheimer's
Study: Depression promote dementia?
Memory loss: emotions remain
Alzheimer's research: billions wasted?
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Image: Gerd Altmann, Pixelio.de