Worldwide, the annual incidence of ALS is 2.5 new cases per 100,000 people. Clinical Progression of ALS Patients are initially prompted to seek medical attention because of a persistent muscle twitch, muscle fatigue or even muscle wasting. This usually starts in the hands or lower legs, and is usually accompanied by cramps. As the disease progresses, patients lose the ability to dress and feed themselves, sit up, walk or even speak. Generally, patients survive three to five years after diagnosis.
Death usually occurs due to respiratory failure.
A biological test does not exist to help establish the diagnosis. It is difficult to diagnose ALS because it resembles other diseases, such as primary lateral sclerosis, progressive bulbar palsy, progressive muscular atrophy, and progressive pseudo bulbar palsy. Typically, neurologists may see only 3-4 ALS patients in their entire career. General practitioners may see only one patient.