title: Gabapentin can improve postural stability and quality of life in primary orthostatic tremor.
abstract: Primary orthostatic tremor (OT) is characterized by leg tremor and instability on standing. High frequency (13-18 Hz) tremor bursting is present in leg muscles during stance, and posturography has shown greater than normal sway. We report on an open-label add-on study of gabapentin in 6 patients with OT. Six patients were studied with surface electromyography, force platform posturography, and a modified Parkinson's disease questionnaire (PDQ-39) quality of life (QOL) scale before and during treatment with gabapentin 300 mg t.d.s. If on other medications for OT, these were continued unchanged. Of the 6 patients, 4 reported a subjective benefit of 50 to 75% with gabapentin, 3 of whom showed reduced tremor amplitude and postural sway of up to 70%. Dynamic balance improved in all 3 patients who completed the protocol. QOL data from 5 patients showed improvement in all cases. No adverse effects were noted. Gabapentin may improve tremor, stability, and QOL in patients with OT, and symptomatic response correlated with a reduction in tremor amplitude and postural sway. The findings confirm previous reports of symptomatic benefit with gabapentin and provide justification for larger controlled clinical trials. Further work is required to establish the optimal dosage and to validate the methods used to quantify the response to treatment.
authors.affiliation: Australian Neuromuscular Research Institute, Centre for Neuromuscular and Neurological Disorders, University of Western Australia, Perth, WA, Australia. jrod@cyllene.uwa.edu.au
authors.forename: Julian P
authors.initials: JP
authors.lastname: Rodrigues
authors.forename: Dylan J
authors.initials: DJ
authors.lastname: Edwards
authors.forename: Susan E
authors.initials: SE
authors.lastname: Walters
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Byrnes
authors.forename: Gary
authors.initials: G
authors.lastname: Thickbroom
authors.forename: Rick
authors.initials: R
authors.lastname: Stell
authors.forename: Frank L
authors.initials: FL
authors.lastname: Mastaglia
mesh_terms: D000368:Aged; D000588:Amines / Q000627:therapeutic use*; D000927:Anticonvulsants / Q000627:therapeutic use*; D003509:Cyclohexanecarboxylic Acids / Q000627:therapeutic use*; D004576:Electromyography / Q000379:methods; D005260:Female; D000077206:Gabapentin; D006801:Humans; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000187:drug effects; D018482:Muscle, Skeletal / Q000187:drug effects; D011187:Posture / Q000502:physiology*; D011312:Pressure; D011788:Quality of Life; D011795:Surveys and Questionnaires; D014202:Tremor / Q000188:drug therapy* / Q000503:physiopathology / Q000523:psychology; D005680:gamma-Aminobutyric Acid / Q000627:therapeutic use*
chemical_list: D000588:Amines; D000927:Anticonvulsants; D003509:Cyclohexanecarboxylic Acids; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin