Frequency of Primary Torsion Dystonia for the Population of Bulgaria – A Service-Based Survey

Abstract

Background: According to the majority of epidemiological studies for primary torsion dystonia (PTD), it is a rare disease, although there are some controversial data, showing much higher figures. Because the need of clarification in this field, the aim of this study is to estimate the frequency of primary torsion dystonia in the Bulgarian population. Materials and Methods: We made an official inquiry to the National Center for Health Information, and to the National Health-Insurance Fund for the total count of all the patients, registered with the diagnose of PTD for a period of a year. Simultaneously we examined the archive of the University Multidisciplinary Hospital for Active Treatment of Neurology and Psychiatry - UMHATNP “St. Naum” in Sofia, with a specialized department of Movement Disorders, for the period of 01.01.2008-01.01.2012. Results: Crude annual prevalence of primary torsion dystonia estimated in this study is significantly lower than most reported epidemiological findings on prevalence. Probably the actual prevalence is higher than that calculated in the current study, but this could be demonstrated by improving the collection of data and methods for screening and diagnosis. Conclusions: The downside of this study, as with most studies in this area worldwide, is that it is based on the demand of medical care. Thus remain not estimated all undiagnosed and and incorrectly diagnosed cases and patients that have not sought medical attention. The majority of the patients in our sample came from the South-Western Region of the country. According to distribution by form of dystonia, age, gender and time to diagnose our results with some exceptions are similar to those, reported in the literature.