Deep Dive Into Amyotrophic Lateral Sclerosis (ALS)

Defining Amyotrophic Lateral Sclerosis

Amyotrophic Lateral Sclerosis (ALS) is a progressive, lethal neurodegenerative disease characterized by voluntary muscle deterioration and paralysis. It is also known as Lou Gehrig’s disease, named after the famous baseball player who was diagnosed with it in 1939. The disease negatively impacts nerve cells in the brain and the spinal cord, initially resulting in muscle twitching, arm or leg weakness, falling/tripping, slurred speech, and difficulty swallowing (i.e., dysphagia). These early symptoms occur because ALS first targets motor neurons in our arms, legs, and feet. However, over time, the disease spreads to other body parts, worsening symptoms. As a result, the motor neurons responsible for breathing, eating, speaking, and moving gradually deteriorate, rendering the muscles incapable of functioning. The cause for the majority of cases remains a mystery, as only 10% of patients are believed to have inherited the illness; the people in this category are classified as “familial/hereditary ALS.” The remaining 90% of patients have no established genetic mutation or family history connecting them to the disease; this group is called “sporadic ALS.”

Further demonstrating how limited our knowledge is concerning ALS, there is currently no cure for this fatal disease. This is important to consider, as the average life expectancy for patients after receiving a diagnosis is three to five years. Approximately 30% of patients have lived past five years, and 10%-20% have survived for 10 years. Therefore, it is crucial for individuals who suspect they may have ALS to contact their medical provider as soon as possible. That way, they can discuss treatment options to slow down the disease’s progression before it continues to damage more nerve cells.

Risk Factors

Aside from genetics, there are several other risk factors correlated with ALS. The first one is age. ALS is most common in patients aged 40-70, with the mean age of diagnosis being 55. With that being said, it can still impact anyone at any age, including those in their 20s and 30s. Another risk factor is gender. Before age 65, men are at a slightly higher risk (60%) of developing ALS compared to women (40%). By age 70, this gender difference disappears. Ethnicity and race are additional risk factors for ALS. Caucasian patients make up 93% of ALS cases; nevertheless, like age, anyone of any race or ethnicity can still develop ALS. Other risk factors in our environment include smoking, toxin exposure, and military service. Menopausal women who smoke are at a particularly higher risk compared to their nonsmoking counterparts. With regard to toxin exposure, some speculate that lead and mercury are linked to ALS; however, there is no substance that has been consistently associated with the development of ALS. In relation to military service, it is unclear why there is this relationship. Some researchers conjecture that this correlation exists because veterans might be exposed to particular chemicals, metals, pesticides, traumatic injuries, viral infections, and/or extreme duress.

Diagnostic Process

Before receiving an ALS diagnosis, patients will need to frequently visit their physician to discuss their symptoms. In these appointments, providers will order a series of tests to confirm an ALS diagnosis, including blood work, urine tests, an electromyography (EMG) to check muscle activity, a nerve conduction study to test nerve cell signaling, and magnetic resonance imaging (MRI) to scan the brain and spinal cord for damage. Other tests in the evaluation include a spinal tap, an X-ray, a CT scan of the cervical spine, and a muscle and/or nerve biopsy. In addition to these assessments, a healthcare provider will also conduct thorough physical and neurological exams on their patients. There are so many assessments because we do not have a single diagnostic test for ALS. Furthermore, because a lot of neurological conditions have similar symptoms to ALS, such as chronic inflammatory demyelinating polyneuropathy (CIDP), physicians need to first rule out other possible ailments to ensure they are making an accurate diagnosis.

Available Treatment Options

Although there is no cure for ALS, practitioners can still recommend treatment options for their patients to delay the onset of certain symptoms. One suggested treatment is medication. Presently, there are several medications that are FDA approved, such as Riluzole, Edaravone, and Tofersen; these drugs work by reducing/slowing down motor neuronal damage to extend their viability. Additionally, a physician could refer their patients to therapies or rehabilitation practices, including physical therapy, occupational therapy, and speech therapy. These services could support patients with strengthening their muscles, learning how to use assistive devices (e.g., wheelchairs), and practicing safe swallowing and communication habits with minimal exhaustion. Other than a speech therapist, a dietician could see ALS patients to help establish a meal plan that consists of easy-to-eat foods that are rich in calories, fiber, and fluids. Such dietary services are crucial for ALS patients, as their impaired swallowing and communication abilities can lead to severe weight loss. Aside from a dietician, patients may be recommended to use a feeding tube to avoid the risk of choking or pneumonia in case food or liquid enters the lungs. A final treatment device physicians could use is a ventilator to help inflate their patients’ lungs with air, especially if they have trouble breathing. Patients could use either a noninvasive ventilator or a mechanical ventilator, depending on their needs.

Steps Moving Forward

Based on the current literature, it is clear that not much is known about ALS. This might be due to multiple factors, such as how rare it is compared to other well-known neurodegenerative diseases, such as dementia. In fact, in the US alone, more than 5,600 patients are diagnosed with this condition per year, which equates to 15 new cases per day. Even though it is not a common disease, that does not take away from its severity and the need for more clinical trials to be conducted. For that reason, many organizations encourage patients with ALS to join clinical trials to improve upon and expand our understanding of this disease to provide better treatment options for patients. Furthermore, education about life-threatening illness is strongly advisable, especially as anyone is susceptible to ALS, and early detection is beneficial.

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