Amyotrophic lateral sclerosis (ALS)

Overview

Amyotrophic lateral sclerosis (ALS), this is often called Lou Gehrig’s disease (named from a famous baseball player in the 1920s). The motor neurons that regulate the voluntary muscles are affected by this neuromuscular disease. Loss of muscular control is a symptom of ALS.

ALS typically impacts both upper and lower motor neurons, which results in their progressive decline and prevents them from effectively communicating with muscles. Motor neurons are nerve cells that are responsible for transmitting signals from the brain and spinal cord to muscles throughout the body, enabling voluntary movement and control.

• Upper motor neurons: the spinal cord and brain’s motor nerve cells. They are tasked with communicating with lower motor neurons.
• Lower motor neurons: the brain stem (lower part of the brain) and spinal cord, which contain motor nerve cells. The upper motor neurons provide them instructions. The muscles in your body are then instructed to move by the messages they send.

A system is used by healthcare professionals to categorize type of motor neuron diseases:

• Classic ALS: More than two thirds of those with ALS have this kind, which is the most common. Lower and upper motor neurons both deteriorate.
• Progressive bulbar palsy (PBP): approximately 25% of ALS patients are affected. When the upper and lower motor neurons in the mouth and throat decline, it first manifests as difficulty speaking, chewing, and swallowing. It is known as bulbar-onset ALS, this condition occasionally progresses to affect the rest of body.
• Progressive muscular atrophy (PMA): This only affects the lower motor neurons.
• Primary lateral sclerosis: The most uncommon type of ALS. The condition only affects the upper motor neurons.

ALS frequently starts with speech slurring, difficulty swallowing, and muscle twitching in an arm or leg. Affected muscles eventually make it difficult to move, speak, eat, or breathe. The symptoms of ALS progressively worsen over time, making it challenging to move, speak, swallow, and eventually breathe. When their lungs are unable to supply enough oxygen to the blood, patients with ALS typically die of respiratory failure.

Currently, there is no known cure for ALS, but advances in therapy have led to improved management of the disease. With the right treatment regimen, the progression of ALS can be slowed down, and the quality of life for individuals with the disease can be enhanced. Despite ongoing research efforts, a definitive cure for ALS has not yet been discovered. Nonetheless, treatments such as medications, physical therapy, and respiratory support can help manage the symptoms and improve the patient’s overall well-being.

Symptoms

Individuals with ALS experience different symptoms. The damaged nerve cells determine which symptoms are present. Muscle weakness is typically the first symptom of ALS, and it progresses and gets worse with time. Some signs and symptoms could be:

• Difficulty walking or performing daily tasks.
• Weakness in the feet, ankles, or legs.
• Cramping and twitching in the muscles, particularly in the hands and feet.
• Weakness or clumsiness in the hands.
• Frequent tripping and falling
• Slurred speech
• Trouble swallowing
• Yawning, laughing, or crying in improper time.
• Changes in behavior and thinking.

The following symptoms can appear as ALS worsens:

• Difficulty in breathing
• Difficulty in chewing and swallowing.
• Unable to independently stand or walk
• Loss of weight because ALS patients burn calories more quickly.
• Patient may become depressed and anxious.

ALS frequently begins in the hands, feet, arms, or legs. After that, it spreads to other body regions. As more nerve cells die, muscles become weaker. It eventually has an effect on breathing, speaking, chewing, and swallowing.

At the onset of ALS, pain is typically not a symptom, and even in later stages, it is not commonly experienced. ALS also does not usually affect normal bladder function or the senses, such as hearing, taste, and smell. While the disease can cause a range of debilitating symptoms, pain and sensory impairment are not typically among them. However, as the disease progresses, individuals with ALS may experience respiratory difficulties and other complications that can impact their quality of life.

Causes

The exact cause of ALS is unknown. Nerve cells that regulate voluntary muscular movements like walking and talking are affected by ALS. Motor neurons refer to these nerve cells. In both kinds of motor neuron, ALS causes a slow deterioration and eventually leads to death. Motor neurons stop transmitting signals to the muscles when they are damaged. The muscles are therefore unable to function properly.

• Genetics: Motor neuron degeneration may be caused by mutations, or alterations, in specific genes. It affects about 10% of people with ALS.
• Environment: ALS may be brought on by exposure to specific pathogens, toxic substances, or physical trauma.

Risk factors

Established risk factors for ALS include:

• Genetics: A risk gene was inherited from a family member in around 10% of ALS patients. Most people with hereditary ALS have a 50% probability of passing the gene on to their offspring.
• Age: Age-related risk increases until age 75. Most people with ALS are between the ages of 60 and 80.
• Sex: Men are slightly more likely than women to develop ALS before the age of 65. After age 70, the sex difference is no longer present.
• Race: The majority of ALS cases occur in white and non-Hispanic individuals.

The following environmental factors have been linked to an increased risk of ALS.

• Smoking: Smoking is confirmed to be an environmental risk factor for ALS. Smoking appears to put women at much greater danger, especially after menopause.
• Environmental factor: ALS may be caused by lead poisoning or other chemical exposure at work or home, according to some research. There has been a lot of research, but no single substance or chemical has been reliably linked to ALS.
• Military service: According to studies, those with military experience are more likely to develop ALS. What aspect of military service might cause ALS is unclear. It could involve exposure to specific metals or chemicals, severe wounds, viral infections, or hard work. Veterans of the military may also be more vulnerable.