Software to test cognitive impairment at the point of care
Computerised cognition testing software that uses an online deck of playing cards to detect early signs of mild cognitive impairment (MCI) and Alzheimer’s disease can also gauge the nature and magnitude of the impairments.
The Cogstate Brief Battery (CBB) is a set of validated tests developed by Australian company Cogstate that has been commercialised as Cognigram and is now being used in Canada as a point of care dementia test.
Through an agreement with Merck Canada, there are now 20 testing centres using the technology, with more than 580 GPs registered to use Cognigram.
The CBB tests attention and reaction times as well as learning and memory. In previous research, it was shown to be able to detect cognitive impairment in MCI and Alzheimer's and in assessing cognitive changes in the preclinical stages of the disease.
This research showed it could be a useful screening tool to assist in the management of cognitive function in clinical settings. In new research published in BioMed Central Psychology, the CBB was able to show the nature and magnitude of cognitive impairments in MCI and Alzheimer's.
Attention/reaction and learning/memory were separated into composite scores and compared to test results with traditional hallmarks of MCI and AD.
Volunteers from the Australian Imaging, Biomarkers and Lifestyle (AIBL) study were divided into three groups: 653 healthy adults, 107 with amnesic MCI (where the primary symptom is memory loss), and 44 with AD.
They were all asked to complete the four tests of the Cogstate Brief Battery and the speed and accuracy of the results were recorded. The tests use a deck of playing cards as their focal point, but no knowledge of any card games is required.
Patients simply answer yes or no to questions when cards are displayed. For the attention/reaction composite, the battery uses the Detection task, in which patients are told to press yes or no on the keyboard as soon as a card is turned over. It also uses the Identification task, answering yes or no if a card turned over is the colour red.
For the learning/working memory composite, two additional tests were used. The One Card Learning task asks the patient if they have seen the card before in the task. To test immediate recall, the One Back test asks if the card displayed is the same as the immediately prior card.
The results showed that both the MCI and the AD groups performed significantly worse on both composites than the healthy adults. Also, the AD group’s learning/memory score was significantly lower than the MCI group, demonstrating the presence and progression of the memory decline caused by the disease.
The tests, which have been developed over some years by a research team led by Paul Maruff of the Florey Institute of Neuroscience and Mental Health and commercialised through Cogstate, are able to show consistent results over time and so can be a reliable diagnostic tool.
Professor Maruff said the battery has been found to be sensitive to amyloid-related cognitive change in many trials. “This study shows for the first time that a version of the test designed specifically for clinical practice, the Cognigram battery, has excellent sensitivity and specificity to mild cognitive impairment,” he said.
In Canada, Cognigram is being used to help doctors detect the subtle changes that can signify the early stages of dementia. It can also be used to monitor changes in cognitive function following concussion or after treatment with drugs or other types of interventions.
It is also being used in clinical trials of drugs and devices as a customisable range of computerised cognitive tasks to measure changes in cognition, including a clinical trial of a new atypical antipsychotic drug for schizophrenia, and in an international study investigating two new interventions for the early treatment of AD.
Cogstate has applied for regulatory approval with the Therapeutic Goods Administration, although there is no timeframe for when it will be available for use by GPs here.
A sample test is available here.
Posted in Australian eHealth