Neurodegenerative diseases: types, symptoms and treatments
Let’s think about the disease that scares us the most. Some people have probably imagined cancer or AIDS, but many others have chosen Alzheimer’s, or another disorder in which there is a progressive loss of abilities (especially mental, but also physical). The idea of losing our abilities (not being able to remember, not being able to move, not knowing who we are or where we are) is part of the deepest nightmares and fears of many.
Unfortunately, for some people it is more than a fear: it is something they are living or expect to live soon. It is about people suffering from neurodegenerative diseases , a concept we will talk about throughout this article.
What are neurodegenerative diseases?
We understand by neurodegenerative diseases the set of diseases and disorders characterized by the presence of neurodegeneration, that is, the progressive degradation until death of the neurons that form part of our nervous system.
This neuronal death is usually progressive and irreversible, causing a series of effects or repercussions of varying severity that can range from no symptomatic effect to progressive loss of mental and/or physical faculties and even leading to death (for example, from cardiorespiratory arrest, one of the most frequent causes of death in this type of condition).
Neurodegenerative diseases are one of the most frequent and relevant causes of disability, since progressive neurodegeneration will end up causing the limitation of functions and the progressive inability to face up to environmental demands, requiring external support and different degrees of assistance .
The causes of this type of disorder or disease can be multiple, and there are a large number of factors that can influence their appearance. The origin in question will depend largely on the neurodegenerative disease we are talking about. However, in most cases the specific causes of the appearance of these pathologies are unknown.
Among the many possible causes suspected for some of them that are known, some causes are found in viral diseases not yet curable that affect the nervous system, the presence of alterations in the autoimmune system that generate that it attacks the body’s own cells, trauma and/or strokes (in the case of vascular dementia). An excess of some elements such as Lewy bodies, beta-amyloid plaques or neurofibrillary tangles is also observed in some dementias, although the reason for their appearance is not known.
Most common types of neurodegenerative diseases
There are a large number of diseases and disorders that can cause the degeneration and subsequent death of the neurons in our nervous system. Dementias and neuromuscular diseases are usually the most known and frequent. Below we can see some examples of some of the most common neurodegenerative diseases.
1. Alzheimer’s disease
One of the best known neurodegenerative diseases is Alzheimer’s disease, perhaps the most prototypical and prevalent problem of this type. This disease, which begins in the temporoparietal lobes and then spreads throughout the brain, has no clear known cause. It generates a dementia characterized by the progressive loss of mental faculties, with memory being one of the most affected elements and the appearance of the aphaso-apraxo-agnostic syndrome in which the abilities to speak, sequence and carry out complex movements and the recognition of stimuli such as faces are gradually lost.
2. Parkinson’s Disease
Parkinson’s is another of the most well-known and common neurodegenerative diseases. In it there is a progressive degeneration of the neurons of the substantia nigra and the nigrostriatal system, affecting the production and use of dopamine in this pathway. The most recognizable symptoms are those of a motor type, with slowing down, alterations in walking and perhaps the best known symptom: Parkinsonian tremors in situations of rest.
It may end up generating a dementia , in which in addition to the above symptoms, mutism, loss of facial expression, mental slowing, memory alterations and other disorders may be observed.
3. Multiple Sclerosis
Chronic and currently incurable disease generated by the progressive demyelination of the nervous system due to the reaction of the immune system against the myelin that covers the neurons . It occurs in the form of outbreaks between which there may be some level of recovery as the body attempts to repair the loss of myelin (although the new myelin will be less resistant and effective). Fatigue, muscle weakness, lack of coordination, visual problems and pain are some of the problems it causes, usually advancing in intensity over time. It is not considered fatal and does not have a great effect on life expectancy.
4. Amyotrophic Lateral Sclerosis
Amyotrophic lateral sclerosis is one of the most frequent neuromuscular disorders, being one of the neurodegenerative diseases linked to the alteration and death of motor neurons. As the neurodegeneration progresses, the muscles atrophy until voluntary movement becomes impossible. Over time, it can affect the respiratory muscles , one of the causes being that the life expectancy of those who suffer from it is greatly reduced (although there are exceptions, such as Stephen Hawking).
5. Huntington’s Korea
The disease known as Huntington’s chorea is one of the best known neurodegenerative diseases of genetic cause . This hereditary disease, transmitted in an autosomal dominant manner, is characterized by the presence of motor alterations, such as chorea or movements generated by the involuntary contraction of muscles, and its displacement is somewhat similar to a dance. In addition to the motor symptoms, as the disease progresses, alterations in executive functions, memory, speech and even personality appear.
The presence of important brain lesions is observed throughout their development, especially in the basal ganglia. It usually has a poor prognosis, greatly reducing the life expectancy of those who suffer from it and facilitating the presence of cardiac and respiratory disorders.
6. Friedreich’s Ataxia
A hereditary disease that alters the nervous system by affecting the nerve cells in the spine and the nerves that control the extremities. The most visible difficulty is that of coordinating movements, muscle weakness , difficulties in speaking and walking and eye movement problems. The progression of this disease often makes those affected need assistance and the use of wheelchairs. It is often accompanied by heart problems.
Treatment of neurodegenerative diseases
Most neurodegenerative diseases are currently incurable (although there are exceptions, as in some cases generated by infections the infectious agent could be eliminated). However, there are treatments that aim to slow the progression of these diseases and prolong the autonomy and functionality of the patient. Depending on the specific case, different medical-surgical procedures can be used that can alleviate the symptoms of the disorder or different medications that prolong the functionality of the subject.
First of all, we must take into account that the same diagnosis will be a hard blow for the patient, generating a probable period of mourning and adaptive problems derived from it. It is likely that anxiety and depression will appear, and even acute or post-traumatic stress disorder depending on the case. In these cases it may be necessary to use psychotherapy , adapting the strategy to each specific case. And not only in the case of the patient, but the caregivers may also experience this type of problem and require professional care.
Psychoeducation for both the patient and the environment with respect to the disease and its consequences is fundamental, contributing to diminish the level of uncertainty they may have and providing mechanisms and strategies for adaptation.
It is common to use neuropsychological rehabilitation , occupational therapy, physiotherapy and speech therapy as part of a multidisciplinary strategy to optimize and prolong the patient’s quality of life, condition, abilities and autonomy. It also often ends up requiring the use of external aids that can be used as compensation or replacement for lost skills such as pictograms, agendas (something as simple as this can be of great help for people with memory and planning problems for example), visual aids or mobility mechanisms such as adapted wheelchairs.
- World Health Organization (2006) Neurological disorders. Challenges to public health. WHO. 45-188.