What Is Amyotrophic Lateral Sclerosis?
Amyotrophic Lateral Sclerosis(ALS) is a progressive neurodegenerative disease affecting the central nervous system [2]. It is also known as motor neuron disease.
ALS is defined by the progressive degeneration of both upper and lower motor neurons [3].
Most ALS cases are sporadic, and the causes are not known. It's believed to be a result of a combination of genetic and environmental factors. Some researchers have proposed a link between ALS and the gut microbiome, but more research is needed to understand the causes of ALS.
However, the disease can have a genetic form known as familial ALS, which can be passed down from a family member. The most common genetic form of ALS results in mutations in SOD1, TARDBP, FUS and C9orf72 genes [4, 5]. Interestingly, C9orf72 is one of the genes which may carry a mutation for familial frontotemporal dementia.
ALS can have multiple forms; the bulbar onset and the spinal onset are the most common ones [6]. However, other such as primary lateral sclerosis or progressive muscular atrophy might also appear. Age, sex, and genetics all contribute to the form of ALS present [6].
ALS Symptoms
The symptoms of ALS include predominantly the muscles. However, cognitive and behavioural symptoms have also been attributed to ALS [7, 8].
- Muscle weakness - Patients experiecne progressive weakening of the muscles in the whole body.
- Slurred Speech - Patients affected by ALS have difficulties generating words due to muscle weakening.
- Stiff Muscles - Patiens experience a sensation in the muscles which presents a challenge in moving the muscles and causes the muscles to hurt.
- Decline in Working Memory - Cognitive decline is one of the symptoms of ALS and refers to problems with memory loss. This is especially common in patients manifesting symptoms of Frontotemporal dementia simultaneously with ALS.
- Sleep Disruptions - Patients suffering from ALS can experience sleep disruption due to muscle pain or breathing difficulties.
ALS can sometimes be confused with Parkinson's disease, especially in the early stages. Both conditions can cause difficulties with movement, speech, and swallowing, but there are significant differences between ALS and Parkinson's.
What Are The 7 Stages of Amyotrophic Lateral Sclerosis?
The disease is by its nature a progressive neurodegenerative disorder. This means, that there is a constant and continuous loss of motor neurons, and the disease worsens over time. The median survival in ALS is only 2-4 years. However, in some special cases it can be longer – this is called a slow progressing ALS. [3, 9].
Stages of Amyotrophic Lateral Sclerosis
Stage 1: Mild Symptoms
In the initial stage, it is very hard to recognize. However, we might observe a change in vocal pitch or a slight weakening of muscles.
Stage 2: Symptom Onset
When the symptoms are all set the patient has difficulties with daily activities, such as walking or grasping and holding objects.
Stage 3: Advanced Disease Stage
At this stage, the muscles are very weak. The patient loses the ability to walk or stand and experiences difficulties with swallowing. The need for a carer is apparent in most of their daily activities.
Stage 4: Difficulty with Eating and Talking
The patient starts experiencing difficulties with eating, swallowing, talking, and breathing as the muscles are weakening. Adjusting the diet to more fluid food is recommended, which might help with swallowing and eating. The patient requires 24-hour care.
Stage 5: Severe Muscle Weakness
In this stage, the patient might require a feeding tube and speech-generating device. The patient loses the ability to use arms and legs properly, and breathing becomes very challenging. The patient requires 24-hour care.
Stage 6: Breathing Problems
The breathing problems worsen, and the patient needs a ventilator to assist with breathing. The patient is bedbound and 24-hour care is needed.
Stage 7: Late Stage: The End-stage of ALS
This refers to the end-of-life stage. The patient is in near-total paralysis and does not communicate with their surroundings. Slight movement of the eyes is present and permanent care is needed.
Is there a cure for ALS?
Unfortunately, as is the case for almost all neurodegenerative diseases, there is no cure for the disease. However, some pharmacological treatments can extend the life expectancy of ALS patients. Other treatments include physical or speech therapy.
Pharmacological Treatment
- Riluzole - Historically, riluzole was the first drug to be approved by the FDA (U.S Food and Drug Administration). It has been shown to extend survival by 2-3 months after 12 months of treatment [10].
- Edaravone - Edaravone is a new anti-ALS drug which uses antisense-oligonucleotide therapy. According to the clinical trials, it seems to slow down the functional decline by 33% [11].
Researchers are working on delivering new treatments for ALS patients. This includes gene therapy for ALS targeting specific mutations but also stem cell therapies [12].
Non-pharmacological Treatment
The non-pharmacological treatment for ALS includes physical therapy and speech therapy. Additionally, ventilators and feeding tubes are also considered non-pharmacological interventions to help the patient with nutrition intake and breathing.
