Amyotrophic Lateral Sclerosis (Lou Gherig's Disease) Amyotrophic Lateral Sclerosis is a deadly disease of the nervous system. Also known as Lou Gehrig’s disease, ALS at this time affects 25,000 people in the U.S. today. One in 50,000 people will be affected in any one year. The average age for diagnosis of ALS is between 30 and 70, although there have been cases of teenagers contracting it.The average life span after diagnosis are three to 10 years, although 20 percent of those affected will outlive their prognosis by a number of years. ALS affects more men than women. Approximately 60 percent of those affected are mal