title: Long-term follow-up of botulinum toxin therapy for focal hand dystonia: outcome at 10 years or more.
abstract: BACKGROUND
  Previous studies have explored the efficacy and safety of botulinum neurotoxin (BoNT) treatment for Focal hand dystonia (FHD), but none have followed a large number of patients for 10 years or more.
  
  
  METHODS
  Retrospective study, with benefit and weakness assessed on a 0 to 4 subjective scale. Demographic, clinical and treatment characteristics were analyzed using t tests and Pearson correlations.
  
  
  RESULTS
  Twenty FHD patients had 10 years or longer treatment. Interinjection intervals were variable. Musicians were more likely to wait longer between injections and had less complex dystonia. There was a trend for larger benefit in women and with shorter intervals. The dose increased over time. Dystonia characteristics did not predict response or side-effects, but benefit magnitude predicted longer compliance. No serious side-effects or antibody-mediated resistance occurred.
  
  
  CONCLUSIONS
  This is the longest reported period of BoNT treatment in the largest FHD cohort. BoNT therapy for FHD remains safe and effective after more than a decade of treatment.
authors.affiliation: Medical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Codrin
authors.initials: C
authors.lastname: Lungu
authors.forename: Barbara I
authors.initials: BI
authors.lastname: Karp
authors.forename: Katharine
authors.initials: K
authors.lastname: Alter
authors.forename: Regina
authors.initials: R
authors.lastname: Zolbrod
authors.forename: Mark
authors.initials: M
authors.lastname: Hallett
mesh_terms: D000328:Adult; D018726:Anti-Dyskinesia Agents / Q000627:therapeutic use*; D001905:Botulinum Toxins / Q000627:therapeutic use*; D004185:Disability Evaluation; D020821:Dystonic Disorders / Q000188:drug therapy* / Q000473:pathology*; D005260:Female; D006225:Hand / Q000503:physiopathology*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D018726:Anti-Dyskinesia Agents; D001905:Botulinum Toxins