Patient may begin to lose awareness of memory loss several years before they are formally diagnosed with dementia, a US study suggests.
Awareness of memory impairment typically begins to decline about two to three years before the onset of dementia, according to the study published in the journal Neurology.
Researchers analysed data on 2,092 participants from three ongoing studies that followed older adults for more than 10 years.
“The findings highlight the importance of testimony from relatives and close friends at the point of diagnosis”
At the beginning of the study, the participants were an average of 76 years old and showed no signs of memory or cognitive impairments.
They were given yearly tests of memory and thinking abilities. They were also asked how often they had trouble remembering things, and how they would rate their memory compared to 10 years earlier.
For the 239 people diagnosed with dementia during the study, memory awareness was stable and then began to drop sharply an average of 2.6 years before the diagnosis of dementia.
This followed several years of memory decline, said the researchers from Rush University Medical Center in Chicago.
Commenting on the findings, Alzheimer’s Society research manager Dr Clare Walton said: “Memory loss can be an important first sign of dementia.
“However, this study shows that people are not always aware of changes to their memory in the early stages of the condition. Often, friends and family are the first to recognise the warning signs,” she noted.
Dr Laura Phipps, from Alzheimer’s Research UK, said: “It’s not an easy task to track people over time before a diagnosis of dementia, and this study presents interesting insights into the changes taking place in the early stages of the condition.
“The findings show that it’s common for people to lose the ability to recognise the memory difficulties they’re experiencing in the lead-up to a diagnosis,” she said. “The findings highlight the importance of testimony from relatives and close friends at the point of diagnosis.”
She added: “Dementia affects everyone differently but it is a progressive condition, which often has a slow and subtle onset. This study only focused on memory changes and it will also be important to track other early signs of dementia in the lead up to a diagnosis.”