Minor moments of memory lapse, such as forgetting to turn off the lights or not remembering a colleague's name, could be a harbinger of dementia.
This is the view of scientists from the University of Kentucky, who believe these so-called senior moments should be taken seriously.
Researchers analysed 531 individuals over a ten-year timeframe and all participants were considered to be of sound mind at the beginning, with an average age of 73. They were given annual memory tests and asked if they had witnessed any changes to their recall ability since their last visit. Doctors undertook autopsies on any patients who had died to see if their brains displayed signs of the degenerative condition.
It transpired more than half of the group - 296 people - reported they had noticed alterations to their memory. These people were the most likely to develop either dementia or mild cognitive impairment (MCI).
MCI tended to be diagnosed around nine years after reporting changes in memory, while dementia was around 12 years.
Out of everyone who experienced dementia, 80 per cent had told the doctor they had noticed their memory deteriorating.
Lead author Professor Richard Kryscio from the University of Kentucky said: "Our study adds strong evidence to the idea that memory complaints are common among older adults and are sometimes indicators of future memory and thinking problems. Doctors should not minimize these complaints and should take them seriously."
However, he added that not everyone who complained about forgetting things would go onto develop MCI or dementia.
Head of research at Alzheimer’s Research UK Dr Simon Ridley stressed the importance of further studies to ascertain why some people with memory problems develop dementia - while others do not.
"Anyone with concerns about their memory should speak to their doctor," he added.
The full findings of this research can be viewed in the journal Neurology.
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