Amyotrophic Lateral Sclerosis (ALS): What It Is & Symptoms

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative condition that affects how nerve cells communicate with your muscles. Amyotrophic lateral sclerosis, or ALS, is a neurodegenerative disease that targets the nerve cells (neurons) in your brain and spinal cord. It leads to muscle weakness that gets worse over time. Symptoms can affect how you move, speak and breathe. This condition affects your muscle control and was formerly known as Lou Gehrig’s disease. Gehrig was a famous baseball player in the 1920s and 1930s who had the condition. An estimated 5,000 people in the United States receive an ALS diagnosis each year.

Types of ALS

There are two types based on their cause:

• Sporadic ALS: The most common type makes up about 90% of cases. It occurs randomly and isn’t inherited.
• Familial ALS: It makes up about 10% of cases. It’s caused by inherited gene changes passed down from a parent.

Symptoms and Progression

ALS causes symptoms that progressively get worse over time. Amyotrophic lateral sclerosis symptoms include:

• Muscle weakness (arms, legs and neck)
• Muscle cramps
• Twitching in your hands, feet, shoulders and/or tongue
• Stiff muscles (spasticity)
• Speech challenges (slurring words, trouble forming words)
• Drooling
• Unintentional emotional expressions (like laughing or crying)
• Fatigue
• Trouble swallowing (dysphagia)

Early symptoms are usually muscle weakness or stiffness in your arms and legs, as well as trouble with speech and swallowing. These can make everyday tasks like writing or eating more challenging. ALS eventually causes your muscles to waste away (atrophy). Atrophy can make it harder to breathe and may lead to life-threatening outcomes. Over time, symptoms typically spread throughout your body. As symptoms get more severe, you may have trouble breathing, standing or walking. You might experience significant weight loss.

Causes and Risk Factors

Researchers don’t know what causes amyotrophic lateral sclerosis. They believe it’s a combination of the following factors:

• Genetics: About 70% of familial cases and 5% to 10% of sporadic cases involve gene changes. They’re most often in the C9orf72, SOD1, TARDBP and FUS genes. There are more than 40 related genes.
• Environment: Exposure to toxins (like lead or mercury), viruses or trauma may also play a role.

What researchers do know is that the disease targets motor neurons. These regulate your voluntary movements, like talking, chewing, moving your limbs and breathing. ALS disrupts communication, like bad phone reception. The messages sent from neurons to muscles break up and don’t get through clearly. This eventually causes the call to end.

Risk factors for amyotrophic lateral sclerosis include:

• Age: You’re most likely to develop symptoms between the ages of 55 and 75.
• Race and ethnicity: White (non-Hispanic) people are most likely to get ALS.
• Sex: For cases that occur before age 55, men are at higher risk.
• Veterans: Military veterans may be at higher risk. Researchers suggest it’s from environmental exposure or physical trauma.

Management and Treatment

ALS treatment includes therapies and medications to manage symptoms and slow the progression of the disease. Although there’s no cure, treatments are constantly improving. The right combination may slow the progression of the disease and improve your quality of life. Contact your healthcare provider if symptoms worsen, and seek emergency care if you’re having trouble breathing.