ALS
![Parts of the [[nervous system]] affected by ALS, causing progressive symptoms in [[skeletal muscles]] throughout the body<ref name="Masrori-2020" />](https://upload.wikimedia.org/wikipedia/commons/1/16/ALS_Affected_neurons_and_muscles.png)
Most cases of ALS (about 90–95%) have no known cause, and are known as ''sporadic ALS''. However, both genetic and environmental factors are believed to be involved. The remaining 5–10% of cases have a genetic cause, often linked to a family history of the disease, and these are known as ''familial ALS'' (hereditary). About half of these genetic cases are due to disease-causing variants in one of four specific genes. The diagnosis is based on a person's signs and symptoms, with testing conducted to rule out other potential causes.
There is no known cure for ALS. The goal of treatment is to slow the disease progression, and improve symptoms. FDA-approved treatments that slow the progression of ALS include riluzole and edaravone. Non-invasive ventilation may result in both improved quality and length of life. Mechanical ventilation can prolong survival but does not stop disease progression. A feeding tube may help maintain weight and nutrition. Death is usually caused by respiratory failure. The disease can affect people of any age, but usually starts around the age of 60. The average survival from onset to death is two to four years, though this can vary, and about 10% of those affected survive longer than ten years.
Descriptions of the disease date back to at least 1824 by Charles Bell. In 1869, the connection between the symptoms and the underlying neurological problems was first described by French neurologist Jean-Martin Charcot, who in 1874 began using the term ''amyotrophic lateral sclerosis''. Provided by Wikipedia