What is ALS?


ALS stands for Amyotrophic Lateral Sclerosis.

Amyotrophic means “loss of muscle tissue” (Myo = muscle).

Lateral Sclerosis means “hardening of the lateral funiculus through scar tissue, through which the pyramidal tracts descend".


ALS Sclerosis off the outer nerve tract in the spinal cord together with muscle atrophy
Atrophy Disappearance through a lack of nutrients
Myo- Muscle
Amyotrofic Wasting of muscle tissue
Lateral Sidelong
Sclerosis Hardening











ALS is a non-contagious neuromuscular condition which can start in every group of muscles and of which the cause has not yet been determined with certainty. Until now there is also no successful treatment or prevention method known. The median survival and course of the disease vary strongly from patient to patient, which makes it difficult to make secure predictions. The illness is mostly fatal within 2 to 5 years after the diagnosis and is this by a paralyzation of the respiratory and swallowing muscles. Yet there is still a big variation when it comes to the life expectancy of ALS patients.

In 1862 Charcot Jean-Marie (born 1825 in Paris) used the term “Amyotrophic Lateral Sclerosis” for the first time to point out to an affection of both the primary as well as the secondary motor neuron. In 1874 it was Charcot who gave the first precise observation of the clinical picture of ALS.

ALS is a progressive condition of the motoric neurons in the brainstem and spinal cord. Nor the sensory, nor the sexual functions are affected. The mental capacities on the other hand can get affected. Approximately 50% is cognitively fully normal. About 35% has mild cognitive or behavioural changes, which are only noticeable with aimed testing. In about 15% of the patients there is FTD (frontotemporal dementia).

ALS results into a loss of strength of the extremities, torso and respiratory muscles and of the swallowing, masseters- and speech muscles.

In some countries ALS is also called MND: motor (movement), neuron (nerve cell), disease (illness).

In the US the illness is named after a the legendary baseball player who passed away from this disease in 1941: ‘Lou Gehrig disease’.

Amyotrophic Lateral Sclerosis (ALS) is a condition that leads to the malfunctioning or disfunctioning of the muscles.

In the case of ALS the motoric anterior horn cells, which can be found in the brains and the spinal cord, are destroyed for an unknown reason. Motoric anterior horn cells are nerve cells that take care of the transfer of stimuli from the brain, via the nerves to the muscles. Because of the fact that these stimuli are not transferred fully anymore, the muscles do not work as well anymore.



Occurrence and heredity

ALS is not a rare disease as it affects six to seven people out of every one hundred thousand. It occurs all over the world. Most people are affected by ALS between the age of fifty and seventy five but there are also teenagers with ALS. Men are affected more frequently than women. The diagnosis can only be determined after all other neurologic conditions have been excluded. The course of the disease is progressive but the evolution varies from one person to another. 

In Belgium 1.000 people continuously suffer from ALS. On a yearly basis more than 200 patients die and at least as many are newly diagnosed with ALS. 

In Europe ALS about 50.000 individuals of middle age are affected by ALS, ALS kills about 10.000 people on a European level. Worldwide 450.000 people suffer from ALS which equals about 6 per every 100.000. Per year 120.000 people are diagnosed with ALS. This means that every day there are 328 new known cases, which equals 2 new diagnoses of ALS per 100.000. 120.000 patients die from ALS every year. 

In about 10% of the ALS-cases there is a genetic pattern. When it concerns the genetic type, ALS is usually the dominant genetic disease, which means the new born/descendant has a 50% chance of becoming ill. The symptoms of genetic ALS are the same as those from the non-genetic form. The only difference is that people with genetic ALS are usually younger when the first symptoms arise. 



The following symptoms occur most frequently with ALS:

Weak and thin muscles

One of the symptoms is the loss of strength in the hands which can be accompanied by the wasting away of a muscle; in a first stage, shoulder and upper arm strength may be affected too. In the case of a “leg type” the legs and feet are affected first, with stumbling and falling as a consequence.

Difficulty chewing, swallowing and speaking

Eating is a complex process which involves numerous muscles: hand and arm muscles, facial and jaw muscles, the tongue, throat and oesophageal muscles. Debility in any of these muscles can cause eating and swallowing problems. In case of weakness of these muscles, the disease is called “bulbar” ALS. People speak indistinctly, their voice gets softer, swallowing and chewing gets more difficult, as do eating and drinking, which can cause drooling in some cases. When the muscles which control swallowing are debilitated, saliva and mucus build up in the mouth. This way, saliva can run out of your mouth or even end up in the airways, which can lead to choking. This often creates a lot of panic for the patient and the people around him. However, choking is hardly ever a cause of death for patients with ALS. It most often occurs when a patient is drinking and not when he is eating solid food. The chances of choking increase in case of fatigue, when emotions run high or when a patient speaks during eating and drinking. Debility of the muscle groups used during speaking can cause communication problems. This phenomenon is called “dysarthria”. Dysarthria goes hand in hand with the aforementioned eating and swallowing problems, as the same muscles are used for chewing, swallowing and speaking. ALS can cause a variety of speech problems, depending on which muscle groups are affected. The patient’s voice can become hoarse or nasal, articulating can get more difficult, as can the pronunciation of certain sounds. Oral hygiene can be affected as well: debilitated tongue muscles and decreased mobility of the palate can hinder the cleaning of the mouth, which leads to dental caries and infections. Therefore, specially adapted nutrition and speech therapy are of utmost importance.

Weight loss and reduced appetite

Because of the loss of muscle mass, reduced food intake, problems with chewing and swallowing and feeling ashamed to eat in company, the body weight can quickly drop.

Trouble breathing

Because of the reduced strength of the respiratory muscles, carbon dioxide accumlates in the blood as a result of which symptoms occur such as troubled sleep, nightmares, morning headaches, drowsiness, shortness of breath and even pneumonia. Patients experience a reduced stamina and are easily fatigued.


Especially tiredness is a common symptom of ALS, seeing as the numerous changes in your life as an ALS patient can result in a general state of stress which can lead to depression and tiredness, “morning tiredness” in particular. This last symptom is especially due to a debilitation of the diaphragm. Because of the declining lung function, this general tiredness increases. All normal activities suddenly require a lot of energy which the body no longer posesses. The psychological acceptance of the diagnosis alone can be challenging and lead to apathy.

Joint and muscle pains, muscle contractions

In fact, ALS is not a physically painful disease, but cramps and stiffness can cause pain in the arms, shoulders and legs. Joint pains are caused mainly by loss of muscle power, by stiffness due to a lack of movement and by maintaining the same posture for a long period of time. Muscle fibre that is not adequately managed by nerve impulses, contracts randomly and causes cramp. However, half of healthy adults are troubled by this as well, especially in the lower legs and feet.

Problems with bowel movement

Constipation can occur because of lack of fluids, reduced physical exercise and the use of certain medicines. People suffering from ALS are often less likely to drink out of fear of problems with swallowing and because they are reluctant to ask for help when going to the toilet. Moreover, going to the bathroom itself becomes difficult because of reduced strength in the abdominal muscles. Adapted food and laxatives may help. 

Compulsive crying, laughing and yawning

These are disinhibition symptoms of the lower cerebral centres. They often start as a normal reaction to something sad or fun, but become uncontrollable and unstoppable after a certain amount of time. This often leads to a feeling of shame, which can cause social isolation.