This is a difficult subject, linked to the fear and the emotional triggers that the mention of this terrible disease can cause. It is still important to understand this disease to better prevent it. Let’s take a moment to learn more about the brain and where this disease comes from.
It is interesting to consider the brain as an extremely complex machine, within which the different sections of the brain have various functions. These different regions communicate with each other via chemical messengers (neurotransmitters) and nerve connections (brain cells called neurons). Inside a single region is a constant balance of a large number of neurotransmitters which can change perceptions, moods, our ability to concentrate, our level of wakefulness and the body’s ability to move. Thus, the brain is the sum of a large number of regions constantly changing their chemical balance.
All the molecules necessary for the production of energy, neurotransmitters and new neurons come from the blood which is transported in the various parts of the brain by arteries, veins and capillaries.
To help you understand dementia and risk factors, we’ll draw an analogy between the brain and how a city works. The large blood vessels (arteries), which carry blood to the brain, are highways that supply the molecules necessary for functioning. The large veins that bring blood from the brain to the heart and lungs are other highways that take waste out. The brain is strewn with regional roads, small side roads and factory yards. The brain is therefore a soft organ, strewn with blood vessels which take care of feeding it and removing waste.
We will return to this analogy to explain the development of the disease, as well as the presentation of risk and prevention factors.
Dementia and Alzheimer’s
Dementia is the term used to define a large number of cognitive problems. According to the definition of the World Health Organization: “this deterioration relates to memory, reasoning, orientation, comprehension, ability to calculate, learning ability, language and judgment”. We can define it more simply by “cognitive disorders which prevent us from enjoying everyday life”. Dementia therefore includes Alzheimer’s, which accounts for 60 to 80% of cases. The second (most common) type of dementia is vascular dementia, including stroke and blockage of the arteries that feed the brain. We will talk in more detail about Alzheimer’s, but remember that all the risk factors and prevention factors that apply to Alzheimer’s, also apply to other forms of dementia, as much in prevention as in slowing the progression of this disease.
The name of a German doctor
Alzheimer’s disease is named after the initial description of the disease in 1906 by a German doctor by the name of Alois Alzheimer. He was the first to link the symptoms of memory loss and the breakdown that results in marked brain degeneration in many patients. Alzheimer’s disease is thought to be largely caused by the accumulation of two specific types of protein: beta-amyloid proteins and tau proteins. The former form plaques that becomes toxic to neurons as they accumulate, and the latter form networks that prevent communication and the delivery of nutrients.
To use the city’s analogy, it’s as if accumulations of waste (beta-amyloid proteins and tau) are detrimental to the proper functioning of factories, neighborhoods and possibly the whole city. The affected cells eventually die and kill the surrounding cells. The factory, which was no longer supplied, ended up closing and also shutting down the shops in the area. These mortality zones accumulate, causing more and more operational problems. For example, the city that no longer has a food service (factory, restaurant) will eventually close.
It is therefore a process that evolves over several years. It seems that the first symptoms can even appear up to 20 years after the onset of waste accumulation problems.
The disease begins with memory loss because the first part of the brain affected is the hippocampus, the seat of memory. Recent studies suggest that this is the first part of the brain affected, due to its proximity to the major arteries that carry blood to the brain.
When does it become worrisome?
Momentary memory lapses are normal and are often linked to fatigue, stress or poor quality of sleep. Don’t worry if you occasionally look for someone’s name or if you forgot an event. However, one should be wary if routine everyday tasks are suddenly impossible or difficult and if certain complex reflections are abnormal. It is always important to consult a professional since these symptoms could be caused by problems with blood circulation to the head or by the side effects of certain drugs. Even if it was Alzheimer’s, it is important to know this as soon as possible, as appropriate treatments can slow the progression of the disease.
In the following articles on Alzheimer’s, we will discuss risk factors as well as prevention methods. In the meantime, do not hesitate to ask us questions.