Epidemiologic features of Guillain-Barré syndrome in São Paulo, Brazil

Abstract

Introduction: 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. Method: 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%). Conclusion: 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.