Multiple sclerosis is considered a leading cause of disability in young adults since it affects people between the ages of 20 and 45. Diagnostic methods are improving, but what causes it is still unknown.
Multiple sclerosis is part of demyelinating diseases. It is a neurological disease characterized by inflammation and myelin’s destruction in the central nervous system, respecting the peripheral nervous system.
The myelin is a lipoprotein surrounding the nervous system’s nerves and allows rapid and efficient transmission of impulses along neurons. Myelin is found in the nerves, central nervous system (brain and spinal cord), and peripheral nervous system (nerves of the limbs and organs). Still, in multiple sclerosis, the central nervous system (CNS) is selectively altered and not the peripheral one, in such a way that the transmission of impulses at that level is delayed, originating the symptoms of the disease.
It is estimated that around the world, there are around 2.5 million people affected by multiple sclerosis, 700,000 of them in Europe. Only in the last two decades have diagnosed cases doubled. Perhaps this is due to improved techniques used to detect it, such as analysis of cerebrospinal fluid or nuclear magnetic resonance imaging. But experts also point out that smoking, vitamin D deficiency, and low exposure to sunlight and certain diet changes could be other possible factors involved in this increase.
It is common for patients with multiple sclerosis to develop other comorbidities, and anxiety disorders and depression (22% and 24%, respectively) are the most frequent. Also, a study presented at the 2020 SEN Annual Meeting, which was carried out in Catalonia among more than 5,500 patients, revealed that these patients not only have a higher risk of developing psychiatric disorders, but also other pathologies such as stroke or epilepsy and that These can delay the diagnosis of multiple sclerosis itself, and increase the rate of flare-ups and the disability that patients develop.
Causes of Multiple Sclerosis
Still, the cause of the disease is unknown, but it is known to have an autoimmune basis. That is, the individual’s immune system would mistakenly act against the myelin-producing cells in the central nervous system (against oligodendrocytes).
Some data support a genetic predisposition to suffer from the disease. Still, it seems that environmental factors (such as viruses) would have to act on this genetic predisposition for multiple sclerosis to develop.
This type of environmental factors, to which women could be more susceptible, could explain that the proportion of women affected is higher than that of men. Experts believe that it may be because they tend to be more hygienic since having less contact with infectious agents could promote autoimmune diseases; and vitamin D since there are more cases of affected in those countries where there are fewer hours of sunshine.
Symptoms of Multiple Sclerosis
The fundamental lesion in multiple sclerosis is the appearance of demyelinating areas or plaques. There are multiple grayish lesions, generally small in size, irregular outlines, and well-defined borders, widely distributed. The regions most affected are:
The optic nerves.
The areas surrounding the ventricles.
The brain stem.
- The cerebellum.
- The spinal cord.
Multiple sclerosis can start suddenly or slowly. The symptoms can be intense or, on the contrary, they can be symptoms so insignificant that the person does not go to the doctor for months or years, being difficult to recognize, which also causes family members or the patient’s environment to not fully understand them and Hence, the invisible symptoms of multiple sclerosis are sometimes talked about.
The disease’s manifestations are very varied and depend on the area of the central nervous system in which the lesions are located and can affect each person differently. Hence it is also known as ‘the disease of a thousand faces.