Glutamate also may lead to the production of detrimental calcium, which can churn out its own supply of DNA-harming free radicals. Abnormalities can lead to an accumulation of the toxic calcium. Typically in ALS, the sensory system and bladder, bowel and sexual function are not affected. In addition, the mental faculties usually remain intact. Targeted at adults in their prime years of life, the average age of onset is the mid-fifties, although adults of all ages can be affected.
Men get the disease slightly more often than women.
Worldwide, the incidence of ALS is 0.5 to 2.4 cases per 100,000, with a prevalence of 2.5 to 7 cases per 100,000 population. The prevalence of AL'S in the United States will -probably increase dramatically as the baby boomer generation ages. ALS is not contagious but may be hereditarily transmitted. Five to ten percent of all ALS occurs more than once in the family line, called Familial ALS, and is inherited as an autosomal dominant trait with high penetrance after the sixth decade. Until the 1990's, the incidence of sporadic ALS was thought to be uniform throughout the Western World.