title: The spread of primary late-onset focal dystonia in a long-term follow up study.
abstract: OBJECTIVE
  To determine spread of primary late-onset focal dystonia at a long-term follow up study.
  
  
  METHODS
  Available patients not lost to follow up from the initial cohort were reexamined to access course and spread of dystonia. In this prolonged follow-up (13.71 ± 5.6 years), it was possible to contact and include 66 out of 132 consecutive patients (50%) who had been diagnosed as primary focal dystonia at the Clinic of Neurology (Belgrade) from January 1990 to January 2000.
  
  
  RESULTS
  Recalculation after inclusion of the new data for 66 patients revealed that the latency from the disease onset to dystonia spreading to the first new region was 4.9 ± 4.9 years, and to the second region 5.9 ± 8.8 years. An average time to disease progression was 12.39 ± 1.58, 6.34 ± 1.55 and 15.95 ± 1.43 for patients with torticollis, blepharospasm, and those with hand dystonia, respectively. The spread of dystonia in patients with the initial blepharospasm was faster, while patients with the writer's cramp could expect further progression even after longer periods of time. Older age at onset (p = 0.061), family history (p = 0.028) and the presence of tremor in the region affected by dystonia (p = 0.047) were the most powerful predictors of disease spreading. The majority of spreading events occurred during the first years of the disease and they appeared to be rare in later period.
  
  
  CONCLUSIONS
  These findings may be valuable for prognostic information on the disorder.
authors.affiliation: Neurology Clinic, Faculty of Medicine, Clinical Centre of Serbia, University of Belgrade, Dr. Subotica Starijeg 6, 11129 Belgrade, Serbia.
authors.forename: Marina
authors.initials: M
authors.lastname: Svetel
authors.affiliation: Institute of Epidemiology, Faculty of Medicine, University of Belgrade, Visegradska 26A, 11129 Belgrade, Serbia.
authors.forename: Tatjana
authors.initials: T
authors.lastname: Pekmezovic
authors.affiliation: Neurology Clinic, Faculty of Medicine, Clinical Centre of Serbia, University of Belgrade, Dr. Subotica Starijeg 6, 11129 Belgrade, Serbia.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Tomic
authors.affiliation: Neurology Clinic, Faculty of Medicine, Clinical Centre of Serbia, University of Belgrade, Dr. Subotica Starijeg 6, 11129 Belgrade, Serbia.
authors.forename: Nikola
authors.initials: N
authors.lastname: Kresojevic
authors.affiliation: Neurology Clinic, Faculty of Medicine, Clinical Centre of Serbia, University of Belgrade, Dr. Subotica Starijeg 6, 11129 Belgrade, Serbia. Electronic address: vladimir.s.kostic@gmail.com.
authors.forename: Vladimir S
authors.initials: VS
authors.lastname: Kostic
mesh_terms: D000328:Adult; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D001764:Blepharospasm / Q000209:etiology; D015331:Cohort Studies; D018450:Disease Progression; D020821:Dystonic Disorders / Q000150:complications / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D006225:Hand; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016019:Survival Analysis; D014103:Torticollis / Q000209:etiology
keywords: Disease progression; Dystonia; Follow-up studies; Retrospective studies