Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig's disease or motor neuron disease (MND), is a progressive neuromuscular degenerative disease that is characterized by degeneration of the motor neurons present in the spinal cord and the brain. When the upper and lower motor neurons start dying, the communication link between the brain and the voluntary muscles break. As a result, the muscles start wasting away, which in turn, gives rise to various distressing symptoms.
When the motor neurons that are present in the bulbar region of the brain, are affected by this condition, one is diagnosed with bulbar ALS. The bulbar region comprises pons and medulla oblongata, and muscles that are controlled by motor neurons in this region adversely affects one's ability to swallow, chew or speak. Thus, people affected by this disease are likely to suffer from dysphagia or dysarthria. In this article, we will look into the causes, symptoms and treatment of this medical condition.
Bulbar Onset ALS
While the exact cause of ALS is not known, it is believed that an inherited genetic defect might sometimes be the causative factor. However, only a small percentage of affected individuals suffer from ALS due to genetic defects. In a majority of cases, identifying or diagnosing the exact cause poses great problems. It is believed that prolonged exposure to environmental toxins or certain drugs may act as triggers. Scientists are also conducting studies in order to ascertain if this condition could be triggered as a result of an autoimmune response.
As far as the symptoms are concerned, the degeneration of the upper and the lower motor neurons hamper the brain's ability to control the voluntary muscles, thereby giving rise to muscle weakness and stiffness. The pattern of the progression of the disease may vary from person to person. Limb onset ALS is more common than the bulbar onset ALS, and usually people develop bulbar symptoms as the disease progresses. Development of bulbar symptoms at the onset of ALS are observed in less than one-third of people who have been diagnosed with ALS. While limb ALS onset gives rise to problems associated with manual dexterity and mobility, bulbar onset ALS is characterized by dysarthria (speech disorder).
The degeneration of the motor neurons in the bulbar region usually gives rise to problems associated with the phonation and articulation of speech. The patient is most likely to experience problems in swallowing (dysphagia), chewing or even breathing. Excessive salivation, twitching, drooling, gagging and exaggerated emotional outbreaks such as pathological laughing or crying are some of the other symptoms that are associated with bulbar ALS.
Prognosis and Life Expectancy
Though the rate at which this disease progresses may vary from person to person, given the nature of the symptoms, the management or treatment of this neurodegenerative disease is certainly more complex than the limb onset. Unlike the limb onset ALS, wherein the patient's mobility is adversely impacted, those who suffer from death of the motor neurons in the bulbar region at the onset of ALS, the complications may result from breathing difficulty. Inability to swallow or breathe, can certainly give rise to life-threatening conditions. Excessive salivation can cause spilling of saliva into the air passages, which in turn, may make one susceptible to bronchospasms. The risk of choking is considerably high in those diagnosed with this condition.
While the average life expectancy for limb onset ALS lies within 3 to 5 years, studies have revealed that about 20% of patients may live beyond 5 years, and about 10% of patients may live more than 10 years after being diagnosed with ALS. The studies reveal that prognosis is poor for patients who suffer from bulbar form of ALS. In case of bulbar onset ALS, the life expectancy is less than 3 years.
This is mainly attributed to the respiratory problems associated with this condition. The progression of bulbar form of ALS takes place at a fast rate, and when it comes to treatment, the doctors emphasize on finding out ways to improve the quality of life of the affected individual. Drug therapy mainly involves the use of riluzole, which is a drug that is believed to slow down the progression of ALS disease. The use of this drug helps in preventing damage to the motor neurons from a substance called glutamate.
While this may help in prolonging the survival rate to some extent, the doctors may suggest use of communication devices and dietary modifications as a part of the symptomatic treatment. While augmentative communication devices can help the patients communicate with others, consumption of liquids or pureed foods can help the patients suffering from dysphagia. Dietary guidelines must also be followed to ensure that the body's needs for nutrients are fulfilled. Since there is a risk of choking due to excessive salivation, doctors may also suggest the use of suction devices. If the patient is unable to swallow food despite using special swallowing techniques, the use of drinking or eating aids would be suggested.
On a concluding note, bulbar ALS is a rapidly progressive medical condition that has a low survival rate and can adversely affect the quality of life of the patient. However, if detected at an early stage, drug therapy and other treatment options can help in slowing down the progression of the disease to some extent. While speech therapy, and use of assistive technology can bring about a marked improvement in the quality of life of the patient, the role of palliative care or support from family members cannot be stressed enough.
The information in this article is intended as a supplement to, not as a substitute for medical advice or treatment provided by medical experts. Since medical experts are in a position to assess and analyze an individual's specific needs and his/her medical history, the readers are advised to consult with a medical expert before following aforementioned treatment options.