Amyotrophic lateral sclerosis (ALS):
Causes, symptoms and course

Amyotrophic lateral sclerosis (ALS) is a disease in which nerve cells in the spinal cord and brain die. It mainly affects motor neurons, which are responsible for movement, speech and breathing. This damage leads to chronic, progressive muscle loss in the arms and legs.

ALS is one of the rare diseases. There are an estimated 500 to 700 people living with ALS in Switzerland, with 100 to 150 new cases diagnosed each year. More men are affected than women, and the first symptoms often appear between the ages of 50 and 70.

The word amyotrophic means “losing muscle mass”. The term “lateral” in ALS refers to a lateral strand in the spinal cord. Sclerosis is the hardening and decreasing elasticity of tissues. In amyotrophic lateral sclerosis, lateral strands in the spinal cord harden, through which the nerves that control the muscles pass.

The symptoms of amyotrophic lateral sclerosis are often weak at the onset of the disease, which is why many cases of ALS are only detected at a late stage. Initially, for example, only hoarseness or slight muscle twitching may occur, which alone do not indicate a serious illness.

People with ALS suffer from one of the following forms of the disease:

• Spinal form: in about 70% of patients, ALS begins in the spinal cord. The first obvious symptoms are often muscle weakness and muscle cramps; at first only in one hand, perhaps, then in both hands, and later also in the arms and legs. However, initial symptoms may also occur in the upper arms or a lower leg.
• Bulbar form: in about 20% to 30% of ALS patients, the disease starts in the brain stem. This results in problems with speaking, chewing or swallowing. Uncontrolled salivation also occurs.
• Respiratory form: in a few ALS patients, the disease begins with breathing problems, such as during physical exertion.

As the disease progresses, the symptoms of all forms usually appear. More than half of those affected suffer from tiredness and fatigue. Pain and depression also occur.

The causes of amyotrophic lateral sclerosis are hardly known. Changes (mutations) in two genes named TDP-43 and SOD1 may play a role, as may defective DNA repair processes. In a few cases, ALS is inherited directly. In this case, we speak of a familial form of the disease. However, ALS usually occurs spontaneously.

The diagnosis of amyotrophic lateral sclerosis (ALS) can be extremely stressful for those affected, as it means that life expectancy is limited and quality of life will deteriorate noticeably. Patients often need a wheelchair or help from others at an early stage.

This makes it all the more important to make use of the available therapy options to counteract the disease process. Physical exercise in particular, as far it is possible, can help.

The Swiss Muscle Society (www.muskelgesellschaft.ch) offers specific assistance for people with ALS and their relatives, including contact with self-help groups. They also provide an overview of therapists who have many years of experience in the treatment of amyotrophic lateral sclerosis.

There are some therapeutic options to relieve the symptoms of ALS and medicines to prolong life expectancy:

• The active substance riluzole reduces the concentration of glutamate in the body. This messenger substance, which is active between nerve cells, damages motor cells in ALS patients.
• The active substance edaravone has cell-protecting properties which slow the progression of amyotrophic lateral sclerosis. Launched only a few years ago, this medicine is approved in Switzerland, Japan and the US.
• Medication can alleviate muscle spasms and the associated discomfort.
• There are also active substances to help with excessive salivation, severe difficulty swallowing, coughing, breathing problems and mucus formation in the airways. Antibiotics can help with respiratory tract infections.
• Physiotherapy is intended to slow down muscle loss and promote physical agility.
• Psychopharmaceutical medicines and psychotherapy can help patients to cope with psychological stress and illnesses such as depression.
• In the advanced stages of the disease, artificial nutrition and a ventilator may be required.

Various new treatment methods are currently being researched. While expectations for the success of stem cell therapy have not been fulfilled recently, scientific hopes are increasingly turning to gene therapy. In certain cases of amyotrophic lateral sclerosis, it is thought to be able to correct genetic defects in the motor neurons and thus slow down the progression of the disease.