What is Amyotrophic Lateral Sclerosis (ALS)?
Amyotrophic lateral sclerosis (ALS) is a progressive disease of the nerve cells in the brain, brain stem and spinal cord that control voluntary muscle movement. Over time, ALS weakens the muscles, which impacts physical function of the body. This is the most common form of adult inherited motor neuron disease. ALS may also be referred to as Lou Gehrig's disease.
Amyotrophic lateral sclerosis can affect anyone, since cases are non-hereditary. More than 5,000 people are diagnosed with ALS each year, with the majority of those being in people aged 40 to 70 years old.
ALS Symptoms
Symptoms of ALS typically do not develop until after age 50. The main symptom is a loss of muscle strength and coordination that eventually gets worse. This loss of strength makes it hard for those with ALS to do routine tasks such as going up steps, getting out of a chair or swallowing.
Weakness can first affect the arms or legs, or the ability to breathe or swallow. As the disease gets worse, more muscle groups develop problems. The disease can affect all skeletal muscles, so weakness can eventually cause problems with walking, changes in speech, difficulties with swallowing and maintaining nutrition, and trouble breathing. Everyone with this disease looks different, so not every person will experience every symptom and it can be difficult to predict which symptoms may develop in each individual.
ALS does not affect the senses (sight, smell, taste, hearing, touch). Most people are able to think normally, although a small number develop dementia, causing problems with speech and thought.
Causes of ALS
Five to 10 percent of ALS cases are caused by genetic defects (inherited ALS). This type of ALS is more likely when more than one family member has the condition. The cause of 90 to 95 percent of cases is currently unknown (sporadic ALS).
Risk Factors for ALS
- Age: Risk increases with age for ALS. Most are diagnosed between the ages of 40 to 70.
- Sex: Men are slightly more prone to develop ALS prior to the age of 65.
- Family History: Inherited ALS affects five to 10 percent of those diagnosed with ALS. Those with this form of ALS often have a 50 percent chance of passing it along to children.
- Environmental toxin exposure: Exposure to different toxins, like heavy metals and smoking, has been proposed to increase ALS risk, although these links have remained difficult to prove.
- Military service: United States military veterans have an increased risk of developing ALS. The exact cause is not known, but may include a number of different factors. Veterans who saw active duty may be eligible for care through the VA ALS clinic.
Is ALS Genetic?
Five to 10 percent of ALS cases are due to a genetic defect. Having more than one family member with ALS makes it more likely that there is a genetic cause for the ALS. There are several gene mutations which have been linked to ALS including SOD1 and C9orf72. While the genetic variant for many cases of familial ALS can be found, in some families we are unable to identify a genetic cause. The cause of many forms of ALS is currently unknown. Current research is being done to expand knowledge about mutated genes as well as therapies that treat specific mutation diagnoses.
How is ALS Diagnosed?
Diagnosing ALS can be difficult due to the gradual onset of symptoms and how the disease often mimics other neurological disorders.
Diagnostic tests may include:
- Biopsy of nerve and/or muscle
- Laboratory testing (blood, urine, spinal fluid)
- Lumbar puncture (spinal tap)
- Nerve conduction studies and electromyography (EMG)
- Neuroimaging (MRI or CT scanning of brain and spine)
How Does ALS Progress?
Over time, people with ALS lose the ability to complete different tasks. Mobility is impacted by arm and leg weakness, swallowing and speaking issues can develop, and breathing can become difficult. While the average prognosis for ALS is three-to-five years after diagnosis, it is not possible to predict this in individual people. At the Penn Comprehensive ALS Center, our physicians and specialists provide guidance to patients and families as the condition progresses so that appropriate care decisions can be made. These circumstances may include:
- Use of mobility equipment, like power chairs, as walking becomes difficult
- Consideration of voice banking to allow for accurate communication before speaking becomes impacted
- The role of gastrostomy tubes to supplement nutrition as swallowing comes affected
- The use of non-invasive ventilation, like BiPAP, to help support respiratory muscles
ALS Treatment
The Penn Comprehensive ALS Center provides multidisciplinary care to patients with ALS and related disorders. Our goals include establishing a definitive diagnosis in patients referred for possible ALS and providing comprehensive care in a supportive and understanding environment which will enable the patient to attain the best possible level of neurological functioning and quality of life.
Treatment for ALS may include the following:
- Medications (including Riluzole®, Relyvrio™, Radicava® and Qalsody™ (tofersen))
- Medications to treat the symptoms related to the disease
- Occupational therapy
- Physical therapy
- Speech therapy
Patients that pursue ALS treatment at the Penn Medicine Comprehensive ALS Center can expect to be visited by one of our nurses and seen by a neurologist. Patients may then choose to be evaluated by our physical therapist, occupational therapist, speech and language pathologist, and dietician.
Patients or families may also request a free consultation with our genetic counselor.
Make an Appointment
To make an expedited appointment with a Penn Medicine ALS neurologist, call 215-829-3053.