Alzheimer’s disease biomarker test, now available to all Canadians, can help physicians properly diagnose the disease, even with mild symptomsexplains Dr. Mari DeMarco, clinical chemist at Saint Paul’s Hospital and associate clinical professor at the University of British Columbia in Vancouver.
Dr. DeMarco’s team developed a key component of this Alzheimer’s disease screening test, as well as the study IMPACT-AD, which aims to work with patients and other healthcare professionals to implement a comprehensive diagnostic strategy.
The test involves measuring changes in the biomarkers of cerebrospinal fluid, the fluid that surrounds the brain and spinal cord. The results allow the doctor to determine if Alzheimer’s disease is causing the symptoms and if the symptoms are likely to get worse over time.
A more conclusive test than the previous ones
A test has been around for a while, but it has been difficult to access it in Canada for clinical use, explains Alexandre Henri-Bhargava, neurologist at the Hospital Royal Jubilee, of Victoria, and associate professor of clinical medicine at the University of British Columbia (UBC), who participates in the program.
It was a difficult test to do from a technical point of view. Different results are obtained depending on the laboratories. […] This is one of the things that has limited the clinical use of this test., he emphasizes.
According to Dr. Henri-Bhargava, Dr. DeMarco’s team
has developed a new test with stable results that can be used for clinical populations.
A breakthrough in treating neurocognitive disorders
Before a test was created, Alzheimer’s disease was clinically diagnosed by the doctor, but this diagnosis could not be confirmed.
The only way to really confirm that the pathology in the brain is Alzheimer’s disease was with an autopsy. With this test, we can confirm the presence of pathological changes that cause the disease., notes Dr Henri-Bhargava.
The doctor can thus guide the treatment of the patient or distinguish this disease from a depressive disorder, he adds.
According to the neurologist at the Royal Jubilee Hospital in Victoria, the study IMPACT-AD check that
the information physicians receive really helps them make important patient decisions and that these patients benefit from discussing the results of that test with their physician .
He adds that this study is used to justify government health spending to offer this test to Canadians.
” This is a test that will become important, since the drugs that are being developed for Alzheimer’s disease will require that we be able to confirm the presence of the disease from a pathological point of view. “
An “invasive” test only accessible to certain doctors
At this time, the test is only offered through a dementia doctor.
The application is, at the moment, quite complex, and the test is offered to the patients who can benefit the most from it., notes Dr Alexandre Henri-Bhargava.
In addition, this restriction is in place because the procedure for collecting the sample which will then be tested in the laboratory of Dr. DeMarco’s team at St. Paul’s Hospital in Vancouver is
a little invasive , according to Dr Henri-Bhargava.
We have to get a sample of the cerebrospinal fluid, a fluid produced in the brain that circulates throughout the central nervous system, through a needle inserted in the back, a lumbar puncture.
The neurologist at the Royal Jubilee Hospital in Victoria hopes the announcement of the program will expand access to the test to all who need it.
In Canada, more than 500,000 people have a neurocognitive disorder like Alzheimer’s disease, and that number could almost double by 2030, according to the Alzheimer Society of Canada.