There are three forms of ALS, the most common, sporadic ALS (sALS); familial ALS (fALS), which is genetically present in only 149 patients from 53 families worldwide (including a rare juvenile form); and an endemic focus of ALS in the western Pacific.1 The worldwide annual incidence rate for sALS is 0.6 to 2.0 per 100,000, and the prevalence is 4 to 6 per 100,000.2 The mean age of onset for sALS is 56 years, with no gender differences noted. The incidence of fALS is only 10 percent of that of sALS, with a 1.5-fold higher disease rate for men. There are no race differences with either form of ALS. There is a higher prevalence of ALS in individuals older than 60 years, and the annual worldwide ALS mortality rate is 1 per 100,000.
Was this article helpful?
This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.