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.

-Lipid-lowering drugs have been occasionally associated with neuromuscular symptoms and muscle biopsy changes. We reported the clinical course and the muscle biopsy in eight patients with hyperlipoproteinemia, treated with lipid -lowering drugs (statins/fibrates). Five patients had myalgias while; in two cases there was proximal muscle weakness. All patients became asymptomatic after the withdrawal of the drug, although creatine kinase remained elevated. We performed muscle biopsy in six cases from three months to two years after suspension of the drug. We found variation in fibers diameters in all cases, with necrosis of fibers in five cases, inflammatory infiltration in one case, the presence of vacuolated fiber in one patient and ragged-red fibers in three subjects. We concluded that although the muscle biopsy findings were not specific, the prolonged use of statins and or fibrates might induce a chronic myopathy even in the absence of symptoms.KEY WORDS: statins, fibrates, myopathy, muscle biopsy, creatine kinase. Miopatia associada a estatina e fibrato: estudo de oito pacientesRESUMO -As drogas redutoras de colesterol são ocasionalmente associadas a sintomas neuromusculares e alterações morfológ-icas observadas na biopsia muscular. Relatamos o curso clínico e achado da biopsia muscular em oito pacientes com hiperlipoproteinemia tratados com drogas redutoras de colesterol (estatinas/fibratos). Cinco pacientes tiveram mialgia e em dois havia fraqueza muscular proximal.Todos os pacientes ficaram assintomáticos após retirada da medicação embora a creatinoquinase permanecesse elevada. Analisamos a biopsia muscular em seis casos realizados entre três meses e dois anos após a suspensão da droga. Encontramos variação no calibre das fibras em todos os casos com necrose de fibras em cinco, infiltrado inflamatório em um caso, presença de vacúolos em um e "ragged red fiber" em três deles. Concluímos que, embora os achados da biopsia muscular não fossem específicos, o uso prolongado de estatinas e/ou fibratos pode induzir a uma miopatia crônica até mesmo na ausência de sintomas.