Alzheimer’s disease and Parkinson’s disease are the two most frequent neurodegenerative diseases. Each year in France, 250,000 people are diagnosed with one of these two diseases. There is currently no treatment to treat these diseases, which are often detected years after the start of symptoms.
They can indeed go unnoticed, since the general public does not necessarily associate them with these diseases. Generally, for Alzheimer’s disease, we only think of memory disorders; And for Parkinson with motor disorders. But these two diseases are actually characterized by many other symptoms, some of which are found both in patients with Alzheimer’s, and certain affairs of Parkinson: depression, confusion, spatial disorientation, attention and concentration disorders, or difficulties in finding the right words.
Another symptom linked to Alzheimer’s and Parkinson, which can occur for years before the disease is declared, has been identified: disorders linked to smell. The regions of the brain linked to this sense would indeed be affected from the start of Alzheimer’s and Parkinson’s disease. According to the France Parkinson association, “more than 90% of people with Parkinson’s disease develop a smell disorder several years before the appearance of motor symptoms”. And according to the CRNS (National Center for Scientific Research), “80 % of Alzheimer’s patients suffer from an olfactory disorder, making it an early signal of the disease”.
Researchers from the Mass General Brigham, recognized as one of the best American hospitals, recently developed an olfactory test, achievable at home, which could make it possible to detect Alzheimer’s disease earlier. With their test, they confirmed that people who have cognitive disorders, in particular characteristic of Alzheimer’s disease, had less good capacity to detect and identify odors. “Early detection of cognitive disorders could help us identify people with a risk of Alzheimer’s disease and to intervene years before the appearance of memory symptoms,” said the main study, Dr. Mark Albers, in a statement.
Detecting Alzheimer’s disease as soon as possible or Parkinson’s disease is a major issue, since the more the disease is taken care of, the more the therapies available today can preserve the quality of life of patients. Even if smell disorders can be a symptom of Alzheimer’s disease or Parkinson, they can be due to other causes such as viral infection – including COVID -19, head trauma or simply aging.
