title: Tremor in primary adult-onset dystonia: prevalence and associated clinical features.
abstract: OBJECTIVE
  To investigate the frequency and the main clinical features of tremor in primary adult-onset dystonia (PAOD).
  
  
  METHODS
  This cross-sectional study was conducted on 429 patients with PAOD from eight Italian movement disorder centres.
  
  
  RESULTS
  Of the 429 dystonic patients, 72 (16.7%) had tremor. Although sex and age at dystonia onset were similar in dystonic patients who had tremor and those who did not, patients who had tremor were affected more often by focal cervical dystonia and less often by focal blepharospasm. Dystonia had a greater tendency to spread in patients with tremor. According to the Movement Disorder Society Consensus Statement, tremor was classified as dystonic tremor (DT) in 43 patients and tremor associated with dystonia (TAWD) in 23 patients. Six patients had both types of tremor. Taking into account potential confounding by age at onset and body distribution of the corresponding dystonia type, all the clinical features in patients with DT and in those with TAWD were comparable except the tendency of dystonia to spread, which was greater in patients with DT.
  
  
  CONCLUSIONS
  Tremor is a relatively common feature occurring in about 17% of patients with primary late-onset dystonia. The association between tremor and dystonia spread suggests that this form of tremor may be a dystonic manifestation. Similarities in phenotypic features of DT and TAWD predominated over differences, suggesting that the two forms of tremor may be manifestations of the same disease. Differences in gender and body distribution of tremor between patients with dystonia and tremor and those of patients with essential tremor also suggest that tremor in dystonia and essential tremor are different entities.
authors.affiliation: Department of Neuroscience and Sensory Organs, 'Aldo Moro' University of Bari, Piazza Giulio Cesare, Bari 2-70124, Italy. gdefazio@neurol.uniba.it
authors.forename: Giovanni
authors.initials: G
authors.lastname: Defazio
authors.forename: Angelo Fabio
authors.initials: AF
authors.lastname: Gigante
authors.forename: Giovanni
authors.initials: G
authors.lastname: Abbruzzese
authors.forename: Anna Rita
authors.initials: AR
authors.lastname: Bentivoglio
authors.forename: Carlo
authors.initials: C
authors.lastname: Colosimo
authors.forename: Marcello
authors.initials: M
authors.lastname: Esposito
authors.forename: Giovanni
authors.initials: G
authors.lastname: Fabbrini
authors.forename: Arianna
authors.initials: A
authors.lastname: Guidubaldi
authors.forename: Paolo
authors.initials: P
authors.lastname: Girlanda
authors.forename: Rocco
authors.initials: R
authors.lastname: Liguori
authors.forename: Lucio
authors.initials: L
authors.lastname: Marinelli
authors.forename: Francesca
authors.initials: F
authors.lastname: Morgante
authors.forename: Lucio
authors.initials: L
authors.lastname: Santoro
authors.forename: Michele
authors.initials: M
authors.lastname: Tinazzi
authors.forename: Paolo
authors.initials: P
authors.lastname: Livrea
authors.forename: Alfredo
authors.initials: A
authors.lastname: Berardelli
mesh_terms: D017668:Age of Onset; D000368:Aged; D003430:Cross-Sectional Studies; D018450:Disease Progression; D004421:Dystonia / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D012737:Sex Factors; D014202:Tremor / Q000453:epidemiology / Q000209:etiology*