Are some types of ALS worse than others?

There can be a lot of variability in how amyotrophic lateral sclerosis (ALS) manifests and progresses, even among people who are classified as having the same type of ALS. In general, ALS disease progression is faster in bulbar-onset disease, where the first muscles affected are in the mouth and throat, compared with limb-onset disease, in which symptoms initially affect the arms or legs.