Updated on 16 September 2013
Cogstate has also been selected as part of the battery of cognition tests in a major global study investigating the early detection of Alzheimer's disease, being run by the international research partnership DIAN (Dominantly Inherited Alzheimer Network) out of the Dominantly Inherited Alzheimer Network Trials Unit (DIAN-TU) at Washington University School of Medicine in St Louis. Cogstate tests are the only computerized cognitive tests included in the study. The Phase II/Phase III clinical trial will evaluate whether two investigational drugs, currently being developed for the treatment of Alzheimer's disease, can halt or reverse pathological changes in the preclinical biomarkers known to be present in patients with the disease.
The AIBL research - four studies in total - used data collected for the major AIBL study to confirm what researchers have long suspected: the link between high beta amyloid levels and an increased risk of Alzheimer's disease. Around 30 percent of Australians aged over 60 years are known to have high brain amyloid levels. At the Alzheimer's Association International Conference (AAIC), held in Boston in July 2013, new data was presented from the study further unravels the links between a person's brain chemistry, genes and their risk of developing Alzheimer's disease (AD). Their research reveals the interplay between two known AD risk factors being the build-up of amyloid plaques in the brain and a common gene variation (BDNF Val66Met).
Brain derived neurotropic factor (BDNF) is a protein which helps existing neurons and encourage the growth of new neurons. It is important for long-term memory. Val66Met is a variant of BDNF which when present in humans alongside high amyloid levels increases the risk of developing dementia. Approximately one in three will carry the BDNF Val66Met gene variation, further increasing their risk of developing dementia. Val66Met has previously been linked to obesity and implicated with memory-related activity, but this is the first time it has been linked to Alzheimer's disease.
The data presented at the conference showed:
• Among healthy older people, and people who meet clinical criteria for mild cognitive impairment (MCI), high brain amyloid levels indicate that AD-related neuro-degeneration has begun and that memory will now decline at a constant rate;
• In healthy older people with abnormally high brain amyloid levels who also carry the BDNF Val66Met gene, memory and other aspects of cognition will decline faster than in those who do not carry this variant; and
• Older people diagnosed with MCI, and who have normal brain amyloid levels, do not show decline in memory over time and therefore their cognitive impairment may be due to other more readily treatable causes such as depression or stress.
The Cogstate tests used in the AIBL (and DIAN) studies is the same technology that is now being rolled out to general practitioner's in Canada, in partnership with Merck. This is a tool that doctors can now use to measure and track cognitive function over time, a useful and accurate tool for early detection of Alzheimer's disease in the clinical setting. Cogstate is looking to roll out the Cognigram test to other global markets.