Alzheimer’s: detect early to treat better
By combining tests with imaging exams, we can spot Alzheimer’s disease (degenerative brain damage) much earlier.
“Thanks to these examinations, we have come out of the blur,” says Professor Bruno Dubois, neurologist at the Pitié-Salpêtrière hospital (Paris). We can now diagnose the disease three to four years before significant symptoms occur, such as behavioral disorders. And this with a reliability close to 100%. “
Alzheimer’s: classic exams
– Memory tests
They last an hour and a half and are based in particular on exercises to reveal disorders of verbal memory. The patient must, for example, learn a list of words and remember it twenty minutes later. These tests can be carried out by a neuropsychologist, a psychiatrist, a geriatrician …
– MRI (imaging test)
It is increasingly part of the balance sheet and assesses the volume of the hippocampus. It is in this region of the brain involved in memorization that the lesions begin. A loss of volume in this area is a characteristic sign of the disease.
Alzheimer’s: examinations for special cases
… and those reserved for special cases
– Lumbar puncture
– Lumbar puncture
It is used to measure the specific substances of the disease in the cerebrospinal fluid (surrounding the brain and spinal cord): tau and beta-amyloid proteins.
– The Pet scan (super-scanner)
By measuring brain function, it can show decreased brain activity in areas affected by amyloid plaques, characteristic of the disease.
Like the lumbar puncture, the Pet scan is intended for special cases: under 50, complicated diagnosis or patient participating in research on the disease. The memory, resource and research centers receive these patients who require in-depth expertise.
Alzheimer’s: a blood test under study
Research is active around the development of a blood test. The first one saw the light of day in 2009. Currently used in research, it may one day be associated with other diagnostic methods (MRI, lumbar puncture, etc.). A second was developed in 2010 by researchers at the Scripps Research Institute (Florida), but has not yet been marketed.
The Research Institute of the McGill University Health Center in Montreal (Canada) is also evaluating the value of assaying dehydroepiandrosterone (DHEA), the production of which decreases in patients. At last, retinal examination may provide information. That of the patients presents, in fact, particular characteristics.
Alzheimer’s: what’s new in terms of treatment
What is the point of diagnosing a disease with modestly effective treatments earlier? First, to ensure better patient follow-up and the training of relatives. And then, the researchers probably haven’t said their last word. The proof ? “A new generation of drugs that act directly on the course of the disease is emerging”, underlines Professor Bruno Dubois. Another avenue under study: a therapeutic vaccine.
With the collaboration of Prof. Bruno Dubois, neurologist, director of the Institute for memory and Alzheimer’s disease at the Pitié-Salpêtrière hospital