Low scores on memory and thinking tests could signal Alzheimer’s 18 years in advance, a new study finds.
Dr Kumar B. Rajan, the study’s lead author, said:
“The changes in thinking and memory that precede obvious symptoms of Alzheimer’s disease begin decades before.
While we cannot currently detect such changes in individuals at risk, we were able to observe them among a group of individuals who eventually developed dementia due to Alzheimer’s.”
In the study, over two thousand people from Chicago were given tests of memory and thinking every three years over 18 years.
Around one in five of the participants, whose average age was 73, developed the disease during the study.
Lower scores on the tests predicted a ten-fold increase in the risk of developing the disease.
Relatively small decreases in performance on the test were linked to large increases in Alzheimer’s risk.
Dr Rajan said:
“A general current concept is that in development of Alzheimer’s disease, certain physical and biologic changes precede memory and thinking impairment.
If this is so, then these underlying processes may have a very long duration.
Efforts to successfully prevent the disease may well require a better understanding of these processes near middle age.”
The study was published in the journal Neurology (Rajan et al., 2015).
→ Explore PsyBlog’s ebooks, all written by Dr Jeremy Dean:
Alzheimer’s photo from Shutterstock