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What do Usain Bolt, Ethel Kennedy, Justin Bieber and the Cookie Monster all have in common? They are just a few of the thousands of people that have participated in the ice bucket challenge: an Internet sensation that has been used to promote awareness of amyotrophic lateral sclerosis in 2014

Amyotrophic lateral sclerosis (ALS) is a progressive neurological disease that causes muscle weakness and gradually impacts on the functioning of the body, leading to eventual death. It is also referred to as motor neuron disease or Lou Gehrig's disease, named after the famous baseball player who had the condition.

The disease was first discovered in 1869 by the French neurologist Jean-Martin Charcot, but it was the impact on Gehrig's career in 1939 that truly brought ALS into public awareness.2

According to the ALS Association, almost two deaths per hundred thousand population annually are due to ALS. In the US, about 5,600 people are diagnosed with the condition every year, with an estimated 30,000 living with ALS at any one moment.3

This Medical News Today article will give you the essential details about ALS. You will also see introductions at the end of some sections to any recent developments that have been covered by MNT's news stories. Also look out for links to information about related conditions.

Fast facts on ALS

Here are some key points about ALS. More detail and supporting information is in the main article.

  • ALS attacks nerve cells found in the brain and spinal cord.
  • The average life expectancy of ALS patients after diagnosis is between 2-5 years.
  • Experts are currently unsure what causes ALS.
  • Common symptoms of ALS include weakness in the limbs and difficulties with speech and breathing.
  • Muscle weakness occurs in 60% of ALS patients.
  • ALS is usually diagnosed based on presenting symptoms while ruling out other illnesses.
  • There is currently no cure for ALS. Treatment focuses on the alleviation of symptoms.
  • As ALS causes a range of physical, social and psychological symptoms, multidisciplinary care teams are important.
  • As well as physical treatment, it is important for ALS patients to receive social and psychological support.
  • As of 25 August 2014, the ice bucket challenge has raised $79.7 million dollars for the ALS Association.


What is ALS?

ALS belongs to a group of diseases called motor neuron diseases. It is a disease that attacks the nerve cells that are used in voluntary muscle actions; actions that we can control such as those in the arms, face and legs.4

As ALS progresses, motor neuron cells in the body degenerate and die.

These nerve cells are called motor neurons and are to be found in the brain and spinal cord. As ALS progresses, these cells degenerate and die, ceasing to send messages to muscles, which in turn causes them to weaken and waste away.

The brain's ability to control voluntary movement is lost, with all muscles under voluntary control being affected over time. As well as control of the arms, face and legs, ALS can cause people to lose the ability to breathe unsupported, often leading to respiratory failure.

ALS greatly reduces an individual's life expectancy; it averages at around two to five years from the point of diagnosis.

There are many examples of people living for much longer, however. After ALS diagnosis, around 20% of people will live five years or more, 10% will live for 10 years or more and 5% will live for a further 20 years.3


What causes ALS? 3,4,5

Currently, experts do not know precisely what causes ALS. It can affect anyone, regardless of gender, race, ethnicity or geographical location. Cases of ALS appear to be inherited in up to 10% of cases, with the cases appearing to occur randomly.

As well as inheritance, researchers are investigating several different possible causes of ALS, including the following:

  • Disorganized immune response: the immune system may attack some of the body's cells, potentially killing nerve cells
  • Chemical imbalance: people with ALS often have higher levels of glutamate, a chemical messenger in the brain, near the motor neurons. Glutamate in high quantities is known to be toxic to nerve cells
  • Mishandling of proteins: if proteins are not processed correctly by nerve cells, abnormal proteins could potentially accumulate and cause the nerve cells to die.

According to the National Institute of Neurological Disorders and Stroke (NINDS), researchers are also investigating whether environmental factors play a role in the development of ALS. For example, a study reported that military personnel deployed in the Gulf region during the 1991 war were more likely to develop ALS than military personnel deployed elsewhere.

Recent developments on ALS causes from MNT news

The origin of Lou Gehrig's disease may have just been discovered

Amyotrophic lateral sclerosis - also known as Lou Gehrig's disease - is a condition that gradually attacks nerve cells that control our voluntary movement, leading to paralysis and death. In the US, a reported 30,000 individuals are living with the disease, but now, scientists have identified a fault in protein formation, which could be the origin of this condition.

Could certain fatty acids reduce the risk of Lou Gehrig's disease?

A new study from researchers at the Harvard School of Public Health in Boston, MA, and published in JAMA Neurology has suggested that eating foods high in omega-3 polyunsaturated fatty acids may reduce the risk of developing amyotrophic lateral sclerosis, the fatal neurogenerative condition that is also known as Lou Gehrig's disease.


Signs and symptoms 4,6,7,8

The symptoms of ALS develop at different rates for different people. The onset of symptoms can be so slight that they can be overlooked until they have developed into more obvious weaknesses or atrophy.

Woman in wheelchair
ALS can make the leg muscles weaken, meaning that once simple actions such as walking can become difficult.

Common symptoms of ALS are:

  • Difficulty in carrying out daily activities, including walking
  • Increased clumsiness
  • Weakness in the feet, hands, legs and ankles
  • Cramping and twitching in the arms, shoulders or tongue
  • Difficulty in maintaining good posture and holding the head up
  • Uncontrolled outbursts of laughing or crying
  • Slurring of speech and difficulty with voice projection
  • Difficulties with breathing and swallowing (in advanced cases).

Muscle weakness occurs in around 60% of all ALS patients. Early symptoms often include clumsiness, abnormal limb fatigue, muscle cramps and twitches (fasciculations) and slurred speech. Symptoms will spread to all parts of the body as ALS progresses.

Some people with ALS can also experience symptoms of impaired decision-making and memory, eventually leading to a form of dementia called frontotemporal dementia.


Tests and diagnosis 4,9

There is no single test that can be used to diagnose ALS. Instead, a health care provider will make a decision based on the symptoms that are presented, alongside using tests in order to rule out other conditions that can cause similar symptoms.

mri scanner
MRI scans can be used to locate problems such as herniated disks that cause symptoms similar to ALS.

Electromyography (EMG) and nerve conduction study (NCS) can detect electrical energy in muscles and the ability of nerves to send signals respectively. EMG and NCS can be used to support ALS diagnosis and rule out peripheral neuropathy (peripheral nerve damage) and myopathy (muscle disease).

Magnetic resonance imaging (MRI) does not reveal evidence of ALS, but can be used to show other problems that could be causing the patient's symptoms. These problems include spinal cord tumors and herniated disks in the neck.

Doctors can also request that blood and urine tests are carried out, as well as tests on spinal fluid samples, extracted with a lumbar puncture. A muscle biopsy can be carried out in order to rule out myopathy.

As well as the conditions mentioned above, the following medical problems can also produce similar symptoms to ALS, and thus may need to be ruled out prior to a diagnosis being made:

The presence of both upper and lower motor neuron symptoms is believed to be a strong indicator of ALS. Upper motor neuron symptoms include stiffness and resistance to movement in the muscles and brisk reflexes. Lower motor neuron symptoms include weakness, muscle atrophy and twitching.10

Recent developments on ALS diagnosis from MNT news

Clinician's 'primer' to genome and exome sequencing published

Experts warn that physicians do not know enough about genetics to understand the strengths and weaknesses of such tools. But clinicians have already ordered several thousand tests - particularly to help with cases of rare childhood diseases - suggesting that, ready or not, the technology has already entered the realm of general medical practice.


Treatment and prevention 4,11,12

There is no cure for ALS and so treatment focuses on alleviating the effects of the symptoms and preventing the development of unnecessary complications.

As the effects of ALS can cause a range of physical, mental and social changes for patients, it may be beneficial to have ALS care managed by an integrated multidisciplinary team of doctors. An integrated team could help to improve the quality of life with ALS and prolong survival.

Riluzole (Rilutek) is the only drug that has been approved for ALS treatment by the Food and Drug Administration (FDA). In some people, it slows the progression of the disease and may work by reducing the body's levels of glutamate. Doctors can also prescribe medication to treat many of the symptoms of ALS.


support group
Support groups can provide emotional support for patients and carers alike.

Physical therapy is helpful in addressing pain and issues with mobility. Low-impact exercises can improve cardiovascular fitness and a sense of well-being. Physical therapists can also help patients adapt to using mobility aids such as walkers and wheelchairs and make suggestions with regards to devices that can make getting about easier such as ramps.

Occupational therapy can help people with ALS maintain their independence for as long as possible. Occupational therapists can suggest adaptive equipment and assistive technology to enable people to continue their daily routines. Therapists can also train people to compensate for hand and arm weaknesses.

Breathing therapy may be required as the disease progresses and the respiratory muscles get weaker. Doctors can provide devices to assist breathing at night, and mechanical ventilation is also an option. In mechanical ventilation, a tube connected to a respirator is inserted in a surgically created hole in the neck (tracheostomy) into the windpipe.

Speech therapy becomes useful when the muscles used in speech become affected by ALS. Speech therapists can teach adaptive techniques when speech becomes difficult. Other methods of communication such as writing can be discussed, or more advanced forms of technology such as computer-based equipment.

Nutritional support is important when swallowing becomes difficult. Nutritionists can advise patients and caregivers on how to prepare meals that are easier to swallow while meeting all of the individual's nutritional needs. Suction devices and feeding tubes can be employed to help individuals eating food orally.

Psychological and social support is important for helping patients and caregivers with the emotional and financial challenges that are created by ALS, particularly as the disease progresses. Support groups can provide comfort through shared experiences, for both patients, family and friends alike.

Recent developments on ALS treatment from MNT news

New small molecules target mutation in ALS and a form of dementia

For the first time, researchers have successfully constructed a strategy targeting a specific genetic mutation that causes amyotrophic lateral sclerosis and a type of dementia. And the exciting news is that their findings show it may be possible to treat a large number of patients who have these two diseases.

Copper compound could form basis for first Lou Gehrig's disease therapy

Lou Gehrig's disease - also known as amyotrophic lateral sclerosis - is an incurable, fatal disease that affects as many as 30,000 individuals in the US. But a new study published in the Journal of Neuroscience suggests a copper compound could be used in therapy for the condition.

The ice bucket challenge

Recently, the ALS Association have been attempting to raise awareness of ALS through the ice bucket challenge: a social media campaign that has spread across the world using the hashtags #icebucketchallenge, #alsicebucketchallenge, and #strikeoutals.

For the fundraising scheme, people are challenged to drench themselves using a bucket filled with ice and water or donate money to the charity. After an icy soaking, the individual is then able to nominate further people to take the challenge.

The ice bucket challenge has proven to be extremely popular, with a whole host of high-profile personalities ranging from Bill Gates to Lady Gaga taking part.

As of 25 August 2014, donations to the ALS Association from the ice bucket challenge have reached $79.7 million. In comparison, during the same timeframe last year the charity received $2.5 million in donations. This figure is good news for researchers attempting to understand the cause of this disease and find effective treatments for this currently fatal condition.

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