This condition is also known as Lou Gehrig’s disease or just ALS. It is a neurodegenerative disease that primarily affects nerve cells called motor neurons.
What is Amyotrophic Lateral Sclerosis?
Amyotrophic lateral sclerosis (ALS) is a disease of the neurons in the brain, brain stem and spinal cord that control the movement of voluntary muscles.
As an interesting fact, the “ice bucket challenge,” in support of the ALS Association, brought some considerable attention to this disease.
Causes
One in 10 cases of amyotrophic lateral sclerosis (ALS) is due to a genetic defect. The cause is unknown in most other cases.
In ALS, motor nerve cells (neurons) die and can no longer send messages to muscles. Over time, this leads to muscle weakness, spasms, and inability to move the arms, legs, and body.
The condition worsens slowly. When the muscles in the thoracic area stop working, it becomes difficult or impossible to breathe.
ALS affects approximately 5 out of 100,000 people worldwide. Having a family member who has an inherited form of the disease is a risk factor for ALS. Some risk factors are controversial.
The destruction of nerve cells (motor neurons) in the brain and spinal cord is what likely causes the disease. These are the nerve cells that send commands to the muscles.
Muscles eventually become useless and waste away. Sometimes this condition occurs because of a genetic defect (familial ALS), but most cases have no genetic basis (sporadic form, accounting for about 90-95% of cases in the USA).
There is currently no consensus on the reasons behind sporadic cases of ALS, with many different environmental factors having been suggested.
Genetic testing is available for members of families affected by familial ALS, but not everybody wants to know if they are at risk of developing the disease.
Symptoms
Symptoms usually do not present until after the age of 50, but may begin in younger people.
People with this condition have a loss of muscle strength and coordination that worsens over time and makes it impossible for them to perform routine activities such as climbing stairs, getting up from a chair or swallowing.
Weakness may first affect the arms or legs, or the ability to breathe or swallow. As the disease worsens, more muscle groups develop problems.
ALS does not affect the senses (sight, smell, taste, hearing, and touch). Most people can think as they usually do, although a small amount has dementia, which causes problems with memory.
Muscle weakness begins in one part of the body, such as the arm or hand, and slowly worsens until it leads to the following:
- Difficulty in lifting things, climbing stairs and walking.
- Difficulty breathing.
- Difficulty swallowing, choking easily, drooling or nausea.
- Head falls due to a weakness of neck muscles.
- Speech problems, such as a slow or abnormal speech pattern (by dragging the words).
- Changes in voice, hoarseness.
Other findings include:
- Depression.
- Muscle cramps.
- Muscle stiffness, called spasticity.
- Muscle contractions, called fasciculations.
- Weightloss.
The first symptoms of ALS are very variable. Muscle weakness may be noted in the legs, arms, or hands.
This may be experienced as something as simple as having difficulty in typing or buttoning a shirt. The patient may also begin to have trouble speaking clearly or swallowing.
Twitching, or uncontrolled laughing or crying, often occur. The symptoms tend to gradually spread, so that a patient may first have problems in the hands, but eventually, the other parts of the body will be affected.
As the disease gradually spreads, breathing becomes difficult, and the patient will need a ventilator.
In some cases, the progress of the disease halts. There is no understanding as to why this occurs.
Overall, the mean survival time is three to five years, although some patients live for a great deal longer.
Tests and exams
Your health care provider will examine you and ask questions about your symptoms and medical history.
The physical exam may show:
- Weakness, which often begins in an area.
- Muscle tremors, spasms, fasciculations or loss of muscle tissue.
- Fasciculations of the tongue (common).
- Abnormal reflexes.
- Rigid or clumsy gait.
- Increased or reduced reflexes in joints.
- Difficulty controlling crying or laughter (sometimes called emotional incontinence).
- Loss of nauseous reflex.
Treatments
Riluzole (Rilutek) is a treatment for ALS. It does not cure the disease but slows its progression.
According to a Cochrane review (a careful review of all the scientific trials on the drug) from 2012, taking riluzole typically gives about two to three extra months of life.
Riluzole is an expensive drug, despite its relatively simple chemical structure.
ISIS-SOD1Rx is an experimental drug from the pharmaceutical company Isis, aiming to treat some forms of familial ALS, which has recently completed initial (phase 1) clinical trials.
Ozanezumab is an experimental drug from the pharmaceutical company GSK, which is currently undergoing clinical trials.
It is a monoclonal antibody, aimed at slowing the progress of the disease by targeting the NOGO-A protein, which is believed to inhibit connections between nerves and muscles.
AEN-100 is a formulation of zinc acetate, currently due to start clinical trials for ALS.
There is a possibility that lack of zinc plays some part in the progression of ALS, so the use of zinc acetate in a form that is gastroretentive (remains for a long time in the stomach) is being investigated.
The drug is produced by Synthetic Biologics. Stem Cell Therapies are currently being investigated for the possible treatment of ALS. It is not clear whether any of these will be successful in practice
Mechanical Ventilation is often required during the latter stages of ALS. Breathing takes place via a tube fitted in the trachea, which connects the lungs to a respirator.
Other Support includes occupational therapy, physical therapy, and speech therapy, all of which can benefit patients.
Physical therapy, rehabilitation and use of orthopedic devices or wheelchairs, or other orthopedic measures may be necessary to maximize muscle function and overall health.
People with ALS tend to lose weight. The disease itself increases the need for food and calories.
At the same time, choking and swallowing problems make it hard to eat enough. A tube can be placed in the stomach to help with feeding. A nutritionist who specializes in ELA can offer tips on healthy eating.