Epidemiological and clinical aspects of a sample of Brazilian patients with primary dystonia and the impact of the new classification on their clinical evaluation

ABSTRACT

Dystonia is a relatively common movement disorder but some of its epidemiological and clinical aspects have not been well characterized in Brazilian patients. Also, a new clinical classification for the disorder has been proposed and its impact on clinical practice is unclear. We aimed to describe the clinical and demographic characteristics of a Brazilian series of patients with primary dystonia, to estimate its local prevalence, and to explore the impact of using a new classification for dystonia. We identified 289 patients with primary dystonia over a 12-month period, of whom235 underwent a detailed evaluation. Patients with primary dystoniamade up one-sixth of all patients evaluated at the service where the study was conducted, with an estimated local prevalence of 19.8/100,000 inhabitants. The clinical and demographic characteristics of the patients were similar to those described elsewhere, with blepharospasm as the most common focal dystonia and most patients using sensory tricks that they judged useful on a day-to-day basis. The application of the new classification was easy and simple, and the systematic approach allowed for a better clinical characterization of our patients. We recognized two dystonic syndromes that were not described in the original article that proposed the classification, and suspected that the arbitrary distinction between generalized and multifocal dystonia seems not to be useful for patients with primary dystonia. In conclusion, the prevalence and clinical characteristics of our patients were not distinct from other studies and the new classification was shown to be practical and useful to characterize patients with dystonia.

RESUMO

A distonia é um distúrbio de movimento relativamente comum e alguns de seus aspectos epidemiológicos e clínicos ainda não foram bem caracterizados em pacientes brasileiros. Além disso, uma nova classificação clínica para o transtorno foi proposta e seu impacto na prática clínica não é claro. Nosso objetivo é descrever as características clínicas e demográficas de uma série brasileira de pacientes com distonia primária, estimar sua prevalência local e explorar o impacto do uso de uma nova classificação para distonia. Foram identificados 289 pacientes com distonia primária (PDYS) durante um período de 12 meses, dos quais 235 foram submetidos a uma avaliação detalhada. Os pacientes com PDYS corresponderam a um sexto de todos os pacientes avaliados no serviço em que o estudo foi realizado, com uma prevalência local estimada de 19,8/100.000 habitantes. As características clínicas e demográficas dos pacientes foram semelhantes àquelas descritas em outros locais, com o blefaroespasmo como distonia focal mais comum e a maioria dos pacientes apresentando truques sensoriais que julgaram úteis no dia-a-dia. A aplicação da nova classificação foi fácil e simples, e a abordagem sistemática permitiu uma melhor caracterização clínica de nossos pacientes. Reconhecemos duas síndromes distçnicas que não foram descritas no artigo original que propçs a classificação e suspeitamos que a distinção arbitrária entre distonia generalizada e multifocal parece não ser útil para pacientes com PDYS. Em conclusão, a prevalência e as características clínicas de nossos pacientes não foram distintas de outras amostras e a nova classificação mostrou-se prática e útil para caracterizar pacientes com distonia.

Keywords:

Dystonic disorder - diagnosis - prevalence

Palavras-chave:

Distúrbios distçnicos - diagnóstico - prevalência

Publication History

Received: 09 May 2018

Accepted: 24 September 2018

Article published online:
22 August 2023

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