Understanding the Causes of ALS-Related Death: Importance of Respiratory Function

Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig's disease, is a progressive and ultimately fatal neurological disorder. It affects motor neurons in the brain and spinal cord, damaging the pathways that control voluntary muscle movement. This leaves patients increasingly weaker and eventually unable to breathe on their own.

Pneumonia and Respiratory Failure in ALS Patients

One of the leading causes of death in ALS patients is pneumonia due to poor cough reflex and respiratory muscle weakness. As the disease progresses, the facial and chest muscles, including the diaphragm, weakened. This results in reduced ability to clear mucus from the airways, leaving the airways filled with secretions. The patient's inability to expel air from the lungs effectively leads to a condition called hypoxic and hypercarbic respiratory failure, where there is insufficient oxygen supply and an accumulation of carbon dioxide in the blood, leading to a state where the body is severely deprived of oxygen, making it impossible for the patient to survive.

Why ALS is So Deadly

The deadliness of ALS is inherently linked to the vital necessity of breathing for survival. ALS selectively attacks motor neurons, including the motor neurons that control the diaphragm, which is responsible for breathing. When these motor neurons die off, the diaphragm no longer receives the necessary signals to contract and relax, leading to a cessation of the breathing function. This is why people with ALS require non-invasive ventilation assistance in the mid-stages of the disease and invasive ventilation with a mechanical ventilator in the later stages.

Respiratory Assistance and Mechanical Ventilation

I have been living with ALS since 2008, and I have significantly struggled with the loss of my ability to breathe independently. Non-invasive ventilation assistance is often sufficient in the middle stages of ALS. In later stages, however, a person will need a tracheotomy, which is a surgical procedure that creates a hole in the throat to allow for a tube to be inserted into the trachea. Through this tube, a mechanical ventilator can deliver air into the lungs. This method helps regulate breathing, but it presents its own limitations, such as the inability to perform a cough, an important reflex for clearing mucus from the airways.

Alternative Solutions for Cough Reflex

Designs for internal electric motors that can simulate breathing by directly stimulating the diaphragm show promise. However, these systems do not include cough reflexes, which are vital for clearing phlegm from the trachea. Without the ability to cough, patients would need alternative methods for pulmonary care. Airway suction, either through a built-in catheter or an external one, is a common method to keep the airways clear.

Conclusion

ALS is a devastating disease that robs its victims of basic life functions, starting with the ability to breathe. The respiratory complications caused by this disease make it one of the primary factors leading to death in ALS patients. Understanding the importance of respiratory function in ALS can help in developing more effective treatments and support systems to improve the quality of life for those affected by this condition.