Dementia tests used by GPs to diagnose the disease may be wrong more than a THIRD of the time
- Three most used tests, taken together, get it wrong 36% of the time
- Fail to identify the disease in highly educated people who do better in the test
- Animal-naming test mistakes normal age-related decline with dementia
Dementia tests commonly used by GPs may misdiagnose more than a third of older people.
Family doctors are the first to see older people when their memory starts to fail, giving them a series of memory and language tests.
But the three most popular tests, taken together, get it wrong 36 per cent of the time.
A study of more than 800 people found the Mini-Mental State Examination, a series of word and number puzzles given to thousands of older people, can fail to identify whether highly educated people have dementia because they do better in the test.
And a simple test in which someone names as many animals as they can in 60 seconds can mistake normal age-related memory problems for dementia.
Dementia tests used by GPs may misdiagnose more than a third of older people (stock)
These false positives and negatives matter because people who are wrongly told they may have dementia face weeks of worry.
GP tests provide the first indication they might have dementia and people are then sent to hospital for a full investigation before being diagnosed.
Older people who actually do have dementia could spend years without the treatment they need because of an inaccurate test result.
The study, led by the University of Exeter, looked at the Mini-Mental State Examination (MMSE), a word recall test called the Memory Impairment Screen (MIS) and the animal naming task.
When 824 people aged 70 to 110 were asked to do them, just over 300 were misdiagnosed by at least one test.
Professor Willie Hamilton, a GP and professor of diagnostics at the University of Exeter and a co-author of the study, said: ‘We must have the best tests available to spot the people who need to be sent to the memory clinic.
‘An early dementia test can help people get early treatment and arrange the finances and support they will need.’
In Britain, 850,000 people are living with dementia, with that number predicted to rise to two million by 2050.
In the study group asked to test the three main assessments, almost two-thirds had dementia, while 35 per cent did not, based on full investigations including three-hour specialist assessments and interviews with family members.
But the Mini-Mental State Examination, which asks people the date and time and where they are, as well as posing language puzzles, misdiagnosed more than one in five.
Highly educated people with dementia were 23 per cent more likely to be told they did not have the condition.
Across all the tests, people were almost five times more likely to be wrongly told they had dementia if they lived in a nursing home.
The Memory Impairment Screen, which asks people to recall four words, with clues if they need them, was wrong 16 per cent of the time.
If people were older or had depression, which can both cause memory problems, they were more likely to be wrongly told they had dementia.
Across the three tests, up to 83 per cent of people given a false-positive had cognitive impairment – memory problems which fall short of dementia and may never turn into it.
Dr Sara Imarisio, head of research at Alzheimer’s Research UK, said: ‘This study highlights the limitations of certain brief cognitive tests of the kind that might be used by GP’s when determining whether to refer a person to a specialist memory service for a more detailed dementia assessment.
‘It is important to also note that GPs don’t rely on these tests in isolation but will also take note of a range of other factors including a person’s medical history, if friends or family members have observed changes in their behaviour, and how well they are able to go about their daily life.’
WHAT IS DEMENTIA? THE KILLER DISEASE THAT ROBS SUFFERERS OF THEIR MEMORIES
Dementia is an umbrella term used to describe a range of neurological disorders
A GLOBAL CONCERN
Dementia is an umbrella term used to describe a range of progressive neurological disorders, that is, conditions affecting the brain.
There are many different types of dementia, of which Alzheimer’s disease is the most common.
Some people may have a combination of types of dementia.
Regardless of which type is diagnosed, each person will experience their dementia in their own unique way.
Dementia is a global concern but it is most often seen in wealthier countries, where people are likely to live into very old age.
HOW MANY PEOPLE ARE AFFECTED?
The Alzheimer’s Society reports there are more than 850,000 people living with dementia in the UK today, of which more than 500,000 have Alzheimer’s.
It is estimated that the number of people living with dementia in the UK by 2025 will rise to over 1 million.
In the US, it’s estimated there are 5.5 million Alzheimer’s sufferers. A similar percentage rise is expected in the coming years.
As a person’s age increases, so does the risk of them developing dementia.
Rates of diagnosis are improving but many people with dementia are thought to still be undiagnosed.
IS THERE A CURE?
Currently there is no cure for dementia.
But new drugs can slow down its progression and the earlier it is spotted the more effective treatments are.
Source: Dementia UK