title: Epidemiologic features of Guillain-Barré syndrome in São Paulo, Brazil.
abstract: BACKGROUND
  There are few epidemiologic studies concerning Guillain-Barré syndrome (GBS). Due to difficulties with definition and lack of a standard diagnostic test of reference, GBS is not easy to study epidemiologically. We evaluate some epidemiological features of GBS in a sample of cases treated at a tertiary hospital in São Paulo, Brazil.
  
  
  METHODS
  We retrospectively reviewed all cases of GBS with hospitalization in Santa Marcelina hospital, over the period of January 1995 through December 2002.
  
  
  RESULTS
  Ninety-five cases were included in this study. Fifty-five were men and forty women, with a proportion of 1.4 men to 1 woman. The age ranged from 1 to 83 years with a mean age at onset of 34 years. GBS was less frequently observed below 15 years (18.9%) and above 60 years (16.9%). The highest frequency was observed in patients aged 15 to 60 years old (66.2%). The annual incidence rate was 0.6 cases/100,000 people. There was a highest frequency of cases during the months of September through March (62.1%).
  
  
  CONCLUSIONS
  Our data differs from that of other epidemiological studies in that we did not observe a bimodal distribution in age and found a seasonal pattern in hotter months.
authors.affiliation: Serviço de Neurologia Clínica, Hospital Santa Marcelina, Sao Paulo, Sp, Brazil. msrocha@uol.com.br
authors.forename: Maria Sheila Guimarães
authors.initials: MS
authors.lastname: Rocha
authors.forename: Sônia Maria Dozzi
authors.initials: SM
authors.lastname: Brucki
authors.forename: Alzira Alves de Siqueira
authors.initials: AA
authors.lastname: Carvalho
authors.forename: Ursula Waleska Poti
authors.initials: UW
authors.lastname: Lima
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D020275:Guillain-Barre Syndrome / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012621:Seasons