Doctors may fail to spot women in the early stages of Alzheimer’s because they are better at remembering lists, researchers have warned.
This superior ‘verbal memory’ often masks the signs of early dementia – meaning a woman’s Alzheimer’s is often missed even if it has deteriorated as far as that of men who are already obviously showing signs of problems.
Experts found women sustained their cognitive performance in standard memory tests even when scans showed Alzheimer’s was already beginning to damage key parts of the brain.
Men, in comparison, began to perform badly in tests as soon as the disease started to take hold.
Women tended to then show a sudden and steep drop in memory later, when their Alzheimer’s had become more advanced, whereas men showed a more gradual decline from earlier in the disease progression.
This superior ‘verbal memory’ often masks the signs of early dementia – meaning a woman’s Alzheimer’s is often missed even if it has deteriorated as far as that of men who are already obviously showing signs of problems
Experts fear that means women too often slip through the net without being diagnosed until their memory begin to rapidly deteriorate.
This can leave women confused and their families struggling without help.
Researcher Professor Pauline Maki, of the University of Illinois, said: ‘These findings may help to explain why women show a more rapid decline across a wide range of cognitive abilities after being diagnosed with Alzheimer’s.
‘While the female advantage may be functionally beneficial, it could mask early stages of Alzheimer’s, resulting in a more severe burden of disease at the time of diagnosis, with more rapid deterioration thereafter.’
The research team, who presented their findings yesterday at the Alzheimer’s Association International Conference in Chicago, carried out brain scans and measured the hippocampus – a key part of the brain linked to memory.
They also examined the scans for signs of plaques building in the brain, a sign of Alzheimer’s, and tested the participants’ spinal fluid for accumulations of toxic amyloid and tau proteins, which are also signs of dementia.
The researchers found that women with early Alzheimer’s or ‘mild cognitive impairment’ performed significantly better in verbal memory tests than men.
But once the Alzheimer’s progressed this difference disappeared.
Dr Tim Shakespeare, research information manager at the Alzheimer’s Society, said: ‘Women are disproportionately affected by dementia globally and 65 per cent in the UK are female.
‘Women tend to have a better memory for things like lists and short stories – known as verbal memory – throughout their lives.
‘This study suggests that this stronger recall in women may mask early symptoms of dementia.
‘Taking this into consideration could help identify dementia early on, so women don’t slip through the dementia diagnosis net.’
He added: ‘Research suggests that when we have new treatments, they will be more effective in the early stages.
‘A timely diagnosis also allows the person access to vital care and support.’
Dr Rosa Sancho, head of research at Alzheimer’s Research UK, added: ‘This study suggests that women’s verbal advantage may be masking the early symptoms of Alzheimer’s, and this could be affecting the accuracy and timeliness of diagnosis.
‘Currently, tests for Alzheimer’s and other forms of dementia don’t take sex-specific differences into account, but this new study suggests this could be a limitation in our approach.’
An estimated 850,000 people in Britain are thought to be living with dementia, a figure that is set to rise to one million by 2025.
Experts last week warned that dementia research is trailing 40 years behind the advances seen in cancer, partly because people have shied away from acknowledging dementia as a medical condition – instead describing people as ‘doddery’ or ‘senile’.
WHAT IS ALZHEIMER’S?
Alzheimer’s disease is a progressive, degenerative disease of the brain, in which build-up of abnormal proteins causes nerve cells to die.
This disrupts the transmitters that carry messages, and causes the brain to shrink.
More than 5 million people suffer from the disease in the US, where it is the 6th leading cause of death.
As brain cells die, the functions they provide are lost.
That includes memory, orientation and the ability to think and reason.
The progress of the disease is slow and gradual.
On average, patients live five to seven years after diagnosis, but some may live for ten to 15 years.
- Loss of short-term memory
- Behavioral changes
- Mood swings
- Difficulties dealing with money or making a phone call
- Severe memory loss, forgetting close family members, familiar objects or places
- Becoming anxious and frustrated over inability to make sense of the world, leading to aggressive behavior
- Eventually lose ability to walk
- May have problems eating
- The majority will eventually need 24-hour care
Source: Alzheimer’s Association