Ataxia unit of the Federal University of São Paulo: 16 years of experience and a description of frequency and etiology

Abstract

Introduction: Cerebellar ataxias are a heterogeneous group of diseases comprising genetic and non-genetic etiologies. Sporadic ataxias are a group of neurological disorders with no family history for ataxia or its related symptoms and signs. Hereditary cerebellar ataxias and hereditary spastic paraplegias (HSP) are rare genetic neurodegenerative disorders with considerable clinical overlap. Objectives: To report a descriptive analysis of the frequency of different forms of cerebellar ataxias evaluated over 16 years in the Ataxia Unit, Federal University of São Paulo, Brazil. Methods: We reviewed charts of patients who were being followed at the Ataxia Unit at Federal University of São Paulo, from January 2007 to December 2022. We used descriptive statistics to present our results as frequencies and percentages of the overall analysis. Patients were classified into the following 8 groups: sporadic ataxias, autosomal dominant cerebellar ataxias, autosomal recessive cerebellar ataxias (ARCA), mitochondrial ataxias, congenital ataxias, X-linked ataxias, HSP, and others. Results: Overall, 1225 Brazilian patients with ataxias or spastic paraplegias. There were 683 patients with a definite diagnosis, which 89 were sporadic ataxias, 322 autosomal dominant cerebellar ataxias, 169 ARCA, 4 congenital ataxias, 6 X-linked ataxias, 16 autosomal dominant HSP, and 35 autosomal recessive HSP. Conclusion: This study describes the frequency of cerebellar ataxias