title: Classification of essential tremor.
abstract: Classification of essential tremor was attempted using tremor frequency; tremor duration; family history of tremor; responsiveness to alcohol, propranolol, and primidone; muscle contraction pattern; and long-latency reflexes. Sixty-one patients were evaluated. The majority of patients had a tremor frequency less than 7.0 Hz, a positive family history, and a positive response to alcohol. Approximately 46% of patients had a beneficial response with propranolol and 71% with primidone. Tremor frequency was inversely correlated with age and directly correlated with an antagonist pattern of muscle contraction. Enhanced long-latency reflexes were not found. Other characteristics of essential tremor were not significantly correlated. It is concluded that essential tremor can not be classified into subtypes.
authors.affiliation: Department of Neurology, University of Kansas Medical Center, Kansas City 66103.
authors.forename: W C
authors.initials: WC
authors.lastname: Koller
authors.forename: K
authors.initials: K
authors.lastname: Busenbark
authors.forename: C
authors.initials: C
authors.lastname: Gray
authors.forename: R S
authors.initials: RS
authors.lastname: Hassanein
authors.forename: R
authors.initials: R
authors.lastname: Dubinsky
mesh_terms: D000368:Aged; D004594:Electrophysiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology; D014202:Tremor / Q000145:classification* / Q000503:physiopathology