Amyotrophic Lateral Sclerosis

What Causes Amyotrophic Lateral Sclerosis (ALS)?

The precise cause of ALS has not yet been determined. The disease occurs in more than one form, and it’s possible that different variants of the disease may have other causes. One common characteristic of various forms of the disease is abnormal changes (called mutations) in specific genes in the patient’s cells. In some cases, these changes are passed on from affected parents to their children. In other cases, the gene mutations may be triggered by external environmental factors.

Scientists don’t yet know exactly which genes are involved in ALS development, nor do they understand how gene mutations lead to the disease’s development.

• Some mutations seem to interfere with the communication between nerve cells and muscles.
• Other mutations may interfere with the function of the nerve cells themselves and cause them to die.
• Still, other mutations may cause toxic substances to accumulate in nerve cells, leading to damage and cell death.

Is Amyotrophic Lateral Sclerosis (ALS) Hereditary?

Of the two broad types of ALS, one definitely has a connection to family history, while the other seems to be linked to non-inherited factors.

• Sporadic ALS. This is the most common type of ALS, affecting about 90% of patients with the disease. This form of the disease doesn’t seem to be linked to family history; it’s probably caused by a combination of gene mutations and external environmental factors. The most common age range for sporadic ALS onset is between the late 50s and early 60s.
• Familial ALS. This form of the disease affects approximately 10% of patients and is clearly linked to genetic family history. In these cases, a mutation in a particular gene appears to substantially increase the risk of developing the disease. A person with the mutation has a 50% chance of passing the mutation on to their child. In families where the ALS mutation is present, multiple family members across generations are likely to have had ALS, or a related disease called frontotemporal dementia (FTD).

Familial ALS often develops earlier than sporadic ALS, with initial onset occurring in the patient’s late 40s or early 50s. In rare cases, the disease can occur in teenagers or children.

How is Amyotrophic Lateral Sclerosis (ALS) Detected?

Doctors often miss the earliest signs of ALS, either failing to diagnose the disease entirely or mistaking the symptoms for another problem. The initial sign of ALS is muscle weakness, but this symptom is not always in the same part of the body. The symptoms might also look like those of different, less severe problems such as a pinched nerve or carpal syndrome. Consequently, ALS is difficult to spot early on, even for medical professionals. Early detection is even more unlikely because the disease is relatively uncommon, and most doctors don’t have experience diagnosing it.

Early signs of ALS include:

• Muscle weakness. There is usually no pain associated with the weakness, and the location of the diminished strength varies from patient to patient. Common areas for loss of strength to begin are the hands, feet, arms, and legs. Patients might also have trouble speaking or swallowing early on.
• Muscle cramps
• Uncontrollable muscle twitches
• Falling or tripping
• Difficulty grasping or holding objects
• Fatigue in the extremities
• Slurred speech
• Difficulty swallowing
• Uncontrollable laughing, crying, or yawning

How is Amyotrophic Lateral Sclerosis (ALS) Diagnosed?

When your doctor suspects that ALS might be the cause of early symptoms, he or she will conduct a variety of tests and exams. There is no single test or exam to detect ALS. Much of the diagnostic process is designed to rule out ALS by identifying other problems that could be causing symptoms rather than directly diagnosing ALS itself.

• Laboratory tests. Tests of your blood and urine will not necessarily confirm a diagnosis of ALS, but the tests may be able to rule out other conditions that could be causing your symptoms.
• Electromyogram (EMG). This test uses electrodes to measure the electrical activity in your muscles as they work. The test can be used to detect abnormalities in muscle function that support a diagnosis of ALS.
• Imaging tests. Magnetic resonance imaging (MRI) scans can detect abnormalities in your brain, spinal column, or other parts of your body. These tests may be used to rule out ALS by revealing another condition that’s causing your symptoms.
• Spinal tap. This procedure removes and tests a small amount of the fluid that protects your brain and spinal column. The test can often detect viral infections or inflammation in the brain.
• Nerve conduction tests. These tests measure how well your nerves can communicate with your muscles. These tests may detect nerve damage or disorders other than ALS that could be causing symptoms.
• Muscle biopsy. In this test, a small amount of muscle tissue is removed and tested. The biopsy is typically used to detect other diseases and to rule out ALS.

How is Amyotrophic Lateral Sclerosis (ALS) Treated?

There is no cure for ALS, and no treatment can undo the damage that the disease does to the body’s nerve cells. Treatment plans, therefore, focus on slowing the progression of the disease, preventing complications associated with the disease, and easing discomfort caused by the disease’s symptoms.

• Drug treatments. Two drugs have been approved for use in ALS treatment, and both drugs have shown success in slowing the disease’s progression. Riluzole is an oral medication that may increase life expectancy by three to six months. Edaravone is administered intravenously; it may increase life expectancy, but studies have not yet shown how long.
• Other medications may be used to treat symptoms such as pain, depression, muscle cramps, fatigue, constipation, sleep disruptions, and uncontrollable crying or laughing.
• Physical therapy can help patients to remain mobile and independent for a longer time as the disease progresses.
• Occupational therapy can help a patient learn how to remain independent as muscle function deteriorates.
• Speech therapy can help to maintain the ability to speak for as long as possible. Treatments can also help the patient learn how to use adaptive technologies to communicate as speech becomes more difficult.
• Breathing therapies can help to ease discomfort as breathing becomes more difficult.

How Does Amyotrophic Lateral Sclerosis (ALS) Progress?

The muscle weakness that’s characteristic of early ALS will eventually spread to other parts of the body, resulting in weakness and paralysis. The sufferer will have increased difficulty moving, speaking, swallowing, and breathing. Usually, patients will eventually be unable to stand, walk, or use their arms and legs, and they will ultimately require mechanical assistance to breathe.

Although there is some evidence that a form of dementia is present in ALS cases, the cognitive function does not usually decline as muscle deterioration progresses. The fact that the sufferer’s mental processes remain intact as their physical abilities decline often leads to depression and anxiety.

How is Amyotrophic Lateral Sclerosis (ALS) Prevented?

The direct cause of ALS is unknown, especially in sporadic ALS cases in which heredity doesn’t seem to play a role. However, research has identified some risk factors that may increase the risk of developing the disease. The risk factors include:

• Smoking. Some research has suggested a link between smoking and ALS, especially in post-menopausal women.
• Military service. Veterans of the military are twice as likely to develop ALS as those who have not served. The increased risk isn’t connected with any type of service, branch of service, combat experience, or location of service. Researchers have not yet been able to determine what aspect of service causes the increased risk.
• Exposure to toxins. Studies have suggested links between ALS and exposure to toxins, including lead, but a definite link between the disease and any one toxin has not yet been established.

Amyotrophic Lateral Sclerosis (ALS) Caregiver Tips

A diagnosis of ALS is devastating both for the patient and for their loved ones and caregivers. The disease is fatal, and coping with that can make dealing with its symptoms and complications even more difficult than otherwise.

• Make room for grief. Therapies and treatments can make the grieving process take a back seat to the daily routine. But giving the grieving process the time and space it deserves is an essential part of coping with the disease.
• Plan ahead. The progression of the disease will make communication and decision-making difficult in the years ahead. Make decisions about medical plans, end-of-life considerations, and financial issues now.
• Recognize the positive. ALS does not usually cause mental decline, and many sufferers have happy, joy-filled experiences for years following their diagnosis. Don’t let the physical symptoms rule out the possibilities.
• Get help. Find a support group for ALS caregivers to help you maintain your mental and physical health as you deal with caregiving demands.

Amyotrophic Lateral Sclerosis (ALS) Brain Science

Researchers are looking for the causes of ALS, for an understanding of how the disease affects the brain, and for effective treatments for the disease. Current studies include:

• Researchers suspect that a brain-cell protein called membralin might play a role in the development of ALS. Scientists don’t know precisely what membralin does in the brain’s nerve cells, but they have found evidence that a deficiency of protein may be a cause of ALS and other degenerative nerve diseases. Their studies suggest that gene therapies that increase levels of membralin may have potential as an ALS treatment.
• One clinical study is currently testing a drug that takes a new approach to treat ALS. The drug aims to improve muscle function rather than improving the communication between nerves and muscles. The hope is that the drug will help muscles to work more efficiently to make up for the weakness caused by ALS nerve damage. The drug seems to be particularly effective at supporting the muscles that control breathing, and patients may breathe better for longer as a result.

Amyotrophic Lateral Sclerosis (ALS) Research

Scientists are working on several research projects to expand on what is known about Amyotrophic Lateral Sclerosis (ALS). The research will improve knowledge about the factors that increase ALS risk and the causes and best treatments and cures and will aid people living with ALS and their caregivers.

We are currently gathering the information required to support projects such as Imaging and BioFluid Biomarkers in Amyotrophic Lateral Sclerosis (TRACK-ALS), Investigating Complex Neurodegenerative Disorders Related to Amyotrophic Lateral Sclerosis and Frontotemporal Dementia, and Cervical Electrical Stimulation for ALS.