What Is Alzheimer's Disease?

The increase in life expectancy is linked to the increase in the prevalence of Alzheimer's disease. Discover one of the diseases with the highest incidence rates in recent years.
What Is Alzheimer's Disease?

Written by Mario Ferrero, 23 April, 2021

Last update: 23 April, 2021

Alzheimer’s is a neurodegenerative disease characterized by the destruction of neurons in the brain and a decrease in brain mass. It’s the most common form of dementia.

It appears after the age of 65, although the chances of suffering from it increase with age. This incurable and terminal disease is characterized by symptoms in which short-term memory losses persist.

Manifestations and symptoms

The first manifestations and symptoms, as we have said, are related to memory loss. Memory disorders directly related to Alzheimer’s disease that lead to suspicion of the onset of this disease are:

  • The inability of the person to remember where they leave frequently used objects.
  • Forgetting recent events and the ability to remember events that happened a long time ago.
  • The difficulty or inability to learn new things or retain new information.

The changes that are observed at a cellular level in the brain of a person with Alzheimer’s are the loss of neurons and synapses in the cerebral cortex. This destruction of neurons is related to the appearance of insoluble extracellular deposits, known as amyloid plaques, and intracellular ones, known as neurofibrillary tangles. This happens more intensely in people with Alzheimer’s than in healthy older people.

The manifestations or symptoms that lead to the deterioration of the cerebral cortex are:

  • Memory impairment
  • Aphasia: Language disorder, difficulty communicating.
  • Apraxia: Inability to execute coordinated movements.
  • Agnosia: Inability to identify the information that comes through the senses.

These symptoms appear as the disease progresses and they don’t all have to appear at once.

Alzheimer's disease.

Stages of Alzheimer’s disease

The condition of a person suffering from this disease occurs in different ways depending on the phase of the disease that patients find themselves in, and it also depends on the patient’s dependence in each phase. We can differentiate 3 stages :

Mild stage

When Alzheimer’s begins to appear, the person begins to suffer mild memory losses, as well as mood swings and difficulties in performing common tasks in their daily routine. Patients also suffer from apathy and isolation in themselves, but still remain independent.

Moderate stage

This is the longest stage. At this time, patients begin to need help to carry out certain complex tasks, but are still able to perform simple tasks.

As this phase progresses, patients are more disoriented and forget recent events, even their personal history and those of the people around them.

Serious stage

During this stage, patients lose the ability to feed themselves, communicate, recognize other people, and lose control of their bodily functions. Patients in this stage become totally dependent.

Causes and risk factors of Alzheimer’s disease

There’s no one specific and confirmed cause that’s responsible for the development of this disease. However, it seems to be produced by the combination of genetic susceptibility added to exposure to environmental factors.

Person forgetting.

There are several risk factors that can increase the chances of suffering from this disease, such as:

  • Age: This is the main risk factor, as the prevalence of the disease doubles every 5 years from the age of 65. As life expectancy increases, the number of people suffering from Alzheimer’s increases.
  • Genetic factors: There’s a clear genetic element in the possibility of developing the disease. Several implicated genes, located in chromosomes 14 and 21, have been observed to be transmitted with autosomal dominant inheritance.
  • Family history of dementia: About 40% of those affected have a family history of dementia.
  • Sex: There is double the prevalence in women compared to men, but this is probably due to the greater longevity of the female sex.

Alzheimer’s disease prognosis

The prognosis of the disease is unfavorable, as its evolution inevitably leads to the total incapacitation of the affected person and death within an average of 15 years.

However, these days, we do have medications that help us slow down the rate at which the disease progresses and which can manage the behavioral problems that people with Alzheimer’s develop.

Anticholinesterase drugs are used that allow a longer time of action of acetylcholine in the synapses. For example, donepezil, galantamine, and rivastigmine. In more advanced stages, memantine is used.

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