What is Alzheimer’s disease?
Alzheimer’s disease (AD) is the most common form of dementia (from 50% to 80% of all cases). First described in 1906 by Dr. Aloïs Alzheimer, this disease is characterized by a progressive and irreversible destruction of the nerve cells (neurons) localized in two specific areas of the brain: the hippocampus and the associative cortex.
What are the symptoms of Alzheimer’s disease?
Neuronal degeneration and subsequent destruction first lead to memory deficit, then to an alteration of personality, language and behavior up to a complete autonomy loss and dementia. Symptoms generally develop slowly and then worsen with time.
What is the life expectancy?
Alzheimer’s disease is the 4th cause of death in adults in France. It equally affects men and women. The majority of patients are over 65 but onset of the disease could occur at age 50 or even 40 in patients suffering from the familial (hereditary) form of the disease.
Death occurs on average eight to twelve years after the first symptoms. This life expectance varies significantly depending on the age of onset.
When the disease starts at age 65, its progression is two times slower than when the disease starts after 70 years old (https://eurekasante.vidal.fr/maladies/systeme-nerveux/maladie-alzheimer.html?pb=evolution-formes).
How is Alzheimer’s disease diagnosed?
Early detection of the disease is based on neuropsychological tests that can identify the first memory issues.
- Magnetic Resonance Imaging (MRI) to measure the volume reduction (atrophy) of certain parts of the brain, including the medial temporal lobe, the hippocampus and the amygdala.
- Positron Emission Tomography (PET) to identify the impaired neuronal metabolism observed in Alzheimer’s disease and to assess the brain lesions called amyloid plaques.
- Cerebrospinal fluid (CSF) analysis can be suggested for persons with an uncertain or atypical diagnosis, and particularly for younger patients. It measures the quantity of proteins produced by the disease (Aβ42, hyperphosphorylated Tau and total Tau).
These tests help diagnose Alzheimer’s disease at an early stage so that treatments and prevention counseling can be initiated as soon as possible.
What are the risk factors?
Age is the leading risk factor for Alzheimer’s disease: it affects 2% of people aged 65 but 15% of people aged 80 and over (https://alzheimer-recherche.org/la-maladie-alzheimer/quest-maladie-dalzheimer/facteurs-de-risques/).
Other risk factors have been identified and are being evaluated, including:
- Level of education
- High blood pressure (hypertension) and strokes
- Hypercholesterolemia, diabetes, excess weight and obesity
- Tobacco and alcohol use
- Sleep disorders
- History of head trauma
- Chronic stress and depression
- Sedentary lifestyle
Conversely, regular physical activity, most particularly aerobics, or the consumption of certain nutrients (high in antioxidant substances) could have a protective effect.
How is Alzheimer’s disease managed?
To this day, Alzheimer’s disease cannot be cured, but its progression can be slowed down and the quality of life of both the patients and their relatives can be improved.
Disease management includes lifestyle, activities, drugs and medicosocial intervention (temporary or permanent care, etc.).
Every case is different and should lead to tailored management.
First of all, it is essential to maintain as many intellectual and physical activities as possible, as well as an active social life.
- Four families of pharmaceutical treatments are frequently prescribed. Three treatments aim primarily at increasing the brain availability of acetylcholine, a neurotransmitter that promotes communication between neurons: donepezil (Aricept), rivastigmine (Exelon) and galantamine (Reminyl)
- Memantine (Ebixa) blocks receptors for glutamate, a molecule that damages neurons, and has an action on the “Tau” component of the disease.