title: Asian over-representation among patients with hemifacial spasm compared to patients with cranial-cervical dystonia.
abstract: OBJECTIVE
  Hemifacial spasm (HFS) is a common movement disorder, but its prevalence in different populations has not been elucidated.
  
  
  METHODS
  We reviewed all patients with HFS currently followed at the Baylor College of Medicine Movement Disorders Clinic and compared their demographic and clinical data with a control group of patients with cranial-cervical dystonia (CD).
  
  
  RESULTS
  In contrast to patients with CD (N=145, mean age 48.64±13.61 years), of whom 117 (80.69%) were Caucasians, 13 (8.97%) Hispanic, 10 (6.90%) African-American, and 5 (3.45%) were of Asian origin, there were 81 (61.36%) Caucasians, 24 (18.18%) Hispanic, 13 (9.85%) African-Americans, and 14 (10.61%) Asians in the HFS group (N=132, mean age 49.33±13.25). Although there was no statistical difference in the age and gender distribution between the two groups, the frequency of Asians in HFS group was 3.1 times higher than that in CD group (P<0.01). Furthermore, the prevalence of Asians among patients with HFS was nearly twice the estimated prevalence of Asians in a general Houston population (5.48%).
  
  
  CONCLUSIONS
  Our results support the observation that HFS is much more common in the Asian population than in other populations. Further epidemiological, genetic, imaging and anatomic studies are needed to understand the apparent difference in the prevalence of this peripherally induced movement disorder.
authors.affiliation: Department of Neurology, Shanghai First People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Yuncheng
authors.initials: Y
authors.lastname: Wu
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Davidson
authors.forename: Tianhong
authors.initials: T
authors.lastname: Pan
authors.forename: Joseph
authors.initials: J
authors.lastname: Jankovic
mesh_terms: D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D000368:Aged; D044466:Asian People; D015897:Comorbidity; D005006:Ethnicity; D005260:Female; D019569:Hemifacial Spasm / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D013781:Texas / Q000453:epidemiology; D014103:Torticollis / Q000453:epidemiology*; D044465:White People