summary
amyotrophic lateral sclerosis (a-my-o-troe-fik lat-ur-ul skluh-roe-sis), or als, is a progressive disease of the nervous system that affects nerve cells in the brain and spinal cord spinal cord, causing loss of muscle control.
Als is often called Lou Gehrig’s disease, after the baseball player with whom it was diagnosed. Doctors usually don’t know why ALS occurs. some cases are inherited.
als often begins with muscle spasms and weakness in a limb, or difficulty speaking. eventually, als affects control of the muscles needed to move, speak, eat, and breathe. there is no cure for this deadly disease.
symptoms
The signs and symptoms of ALS vary greatly from person to person, depending on which neurons are affected. it usually begins with muscle weakness that spreads and worsens over time. signs and symptoms may include:
- difficulty walking or performing normal daily activities
- trip and fall
- weakness in the legs, feet, or ankles
- weakness or clumsiness in the hand
- difficulty speaking or difficulty swallowing
- muscle cramps and spasms in the arms, shoulders, and tongue
- inappropriate crying, laughing, or yawning
- cognitive and behavioral changes
- inheritance. 5 to 10 percent of people with als have inherited it (familial als). In most people with familial ALS, their children have a 50-50 chance of developing the disease.
- age. the risk of disease increases with age and is most common between the ages of 40 and mid-60s.
- sex. Before the age of 65, slightly more men than women develop als. this sex difference disappears after age 70.
- genetics. Some studies that examined the entire human genome found many similarities in the genetic variations of people with familial ALS and some people with non-inherited ALS. these genetic variations can make people more susceptible to ela.
- smoking. Smoking is the only likely environmental risk factor for ALS. the risk appears to be greater for women, particularly after menopause.
- exposure to environmental toxins. some evidence suggests that exposure to lead or other substances in the workplace or home may be related to als. Many studies have been done, but no single agent or chemical has been consistently associated with als.
- military service. studies indicate that people who have served in the military are at increased risk for als. it is unclear what it is about military service that could trigger the development of als. could include exposure to certain metals or chemicals, traumatic injuries, viral infections, and intense exertion.
These often start in the hands, feet, or extremities and then spread to other parts of the body. As the disease progresses and nerve cells are destroyed, the muscles weaken. this ultimately affects chewing, swallowing, speech, and breathing.
There is usually no pain in the early stages of ALS, and pain is uncommon in the later stages. als does not usually affect bladder control or the senses.
causes
als affects the nerve cells that control voluntary muscle movements, such as walking and talking (motor neurons). als causes motor neurons to gradually deteriorate and then die. Motor neurons extend from the brain to the spinal cord and muscles throughout the body. when motor neurons are damaged, they stop sending messages to the muscles, so the muscles cannot function.
als is inherited in 5% to 10% of people. otherwise the cause is unknown.
Researchers continue to study possible causes of ALS. most theories focus on a complex interplay between genetic and environmental factors.
risk factors
Established risk factors for ALS include:
environmental factors, such as the following, can trigger it.
complications
As the disease progresses, complications also occur, such as:
respiratory problems
Over time, als paralyzes the muscles you use to breathe. he may need a device to help him breathe at night, similar to what someone with sleep apnea might wear. for example, you may be given a bilevel positive airway pressure (bipap) device to help you breathe at night. This type of device helps you breathe through a mask that fits over your nose, mouth, or both.
Some people with advanced ALS choose to have a tracheostomy (a surgically created hole in the front of the neck that leads to the trachea) to use a ventilator that inflates and deflates the lungs full-time.
The most common cause of death for people with ALS is respiratory failure. on average, death occurs within 3 to 5 years after the onset of symptoms. however, some people with it live 10 years or more.
trouble speaking
Most people with it develop trouble speaking. this usually starts as mild slurred speech occasionally, but becomes more severe. over time, speech becomes difficult for others to understand, and people with it often rely on other communication technologies to communicate.
feeding problems
People with ALS can develop malnutrition and dehydration due to damage to the muscles that control swallowing. they are also at higher risk of food, liquid, or saliva getting into the lungs, which can cause pneumonia. a feeding tube can reduce these risks and ensure proper hydration and nutrition.
dementia
some people with it have problems with memory and decision-making, and some are eventually diagnosed with a form of dementia called frontotemporal dementia.