title: Onset, natural history and outcome in idiopathic adult motor neuron disease.
abstract: Cases of adult-onset idiopathic motor neuron disease (MND) identified from January 1970 through December 1986 were studied in a defined area of California. The patients were followed prospectively throughout the illness in 99% of cases. Among 708 cases aged 25-74 years at onset, the most common type (86%) was typical, sporadic amyotrophic lateral sclerosis (SporALS). The risk of bulbar onset and shorter survival times increased with age in both men and women. About 4%, mainly younger men, experienced unusually long courses with milder paralysis, but could not be identified early in the illness. They probably represent one extreme of the ALS spectrum rather than a distinct subtype. Familial ALS (FamALS) was diagnosed in 7%. It developed earlier in life but ran a slightly longer course, which suggests a different disease process. Overall there was a statistically significant predominance of males, especially in 17 cases (2%) of progressive muscular atrophy (PMA). There were 26 cases (4%) classified as primary lateral sclerosis (PLS). Progressive bulbar palsy was not found; that diagnosis usually denotes merely the bulbar onset of ALS.
authors.affiliation: ALS Research Foundation, California Pacific Medical Center, San Francisco.
authors.forename: F
authors.initials: F
authors.lastname: Norris
authors.forename: R
authors.initials: R
authors.lastname: Shepherd
authors.forename: E
authors.initials: E
authors.lastname: Denys
authors.forename: K
authors.initials: K
authors.lastname: U
authors.forename: E
authors.initials: E
authors.lastname: Mukai
authors.forename: L
authors.initials: L
authors.lastname: Elias
authors.forename: D
authors.initials: D
authors.lastname: Holden
authors.forename: H
authors.initials: H
authors.lastname: Norris
mesh_terms: D000328:Adult; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D000690:Amyotrophic Lateral Sclerosis / Q000453:epidemiology; D002140:California; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016472:Motor Neuron Disease / Q000453:epidemiology*; D009133:Muscular Atrophy / Q000453:epidemiology; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012727:Sex Characteristics; D013534:Survival