Have you heard of Tourette syndrome? In Spain, it is still considered a rare disease based on its prevalence in the population. However, studies at the international level indicate that the disorder is actually much more common than previously thought [1,2].
Given that , June 7, is European Tourette Syndrome Awareness Day, today’s post is dedicated to debunking common myths and misconceptions about Tourette’s.
Let’s deconstruct Tourette syndrome.
WHAT IS TOURETTE SYNDROME?
According to international diagnostic criteria, Tourette syndrome (TS) is a primary motor disorder with the chronic presence of tics as a core feature [3,4], and is often associated with other conditions such as ADHD and OCD .
WHAT DEFINES A TIC?
The word tic derives from the Italian ticchio  meaning caprice as synonym of whim and extravagance [6,7]; however, far from being a whim or caprice of the individual who manifests them, tics are involuntary movements or vocalizations, although they may be extravagant because they appear repetitively with an inappropriate intensity and frequency, and are decontextualized or unrelated to situations since they are not goal-directed behaviors like voluntary movements  or the voluntary emission of words or sounds.
- More than a syndrome, it is a spectrum disorder. Different subtypes of Tourette’s have been described [1,9], which is why it is currently considered more appropriate to speak of the spectrum of Tourette disorder rather than of Tourette syndrome .
- Blurting out obscenities is a rare symptom of Tourette’s. Coprolalia (inappropriate involuntary uttering of obscenities without offensive intent [1,10]) is one of the most popular symptoms of TS, partly due to its diffusion through cinema and media. Although coprolalia might certainly be one of the most significant features, it only occurs in less than one fifth of affected individuals .
- Special creativity for music. Although there is no linear relationship between excess of dopamine and creativity, the scientific literature emphasizes an association between Tourette’s disorder and musical creativity .
- Its origin is not psychological. The idea that the aetiology of Tourette syndrome was psychological has now been discredited  since aetiological suggestions include genetic factors and environmental influences .
A month ago, a study published in Neuron estimated that there are approximately 400 genes that contribute risk in 12% of clinical cases .
- Its pathophysiology is not limited to the basal ganglia. The anatomo-functional alterations involved in TS comprise multiple cortical and subcortical structures and not only the basal nuclei , which are associated with the automatization of voluntary behavior. Concerning tics, different cortico-striato-thalamo-cortical circuits are involved and are of four modalities: sensorimotor, orbitofrontal, limbic and associative loops , and may be altered at varying degrees in individuals with Tourette syndrome.
- Is much more common than previously thought. The European Commission on public health determines that rare diseases are conditions with prevalence below 0.05% , however, different studies suggest that the overall international prevalence of Tourette syndrome is 1% in the majority of cultures of the world 2],which is similar to the prevalence of schizophrenia.
- In Spain, it is likely that the current estimate is well below the real one. The overall international prevalence of 1%  suggests that in Spain, the classification of Tourette syndrome as a rare disease based on a low prevalence (below 0.05%) may be an underestimation. A fact that supports this hypothesis is that the current number of individuals diagnosed with TS recorded on the National Registry of Rare Diseases in Spain is 33 people , which is much less than 1% of Spain’s population, now at 46,468,102 according to the most recent figures reported by the National Statistics Institute .
By: Lidia García Pérez
- Robertson, M.M. (2012). The Gilles De LaTourette syndrome: the current status. Archives of Disease in Childhood: Education & Practice, 97(5), 166-175. http://dx.doi.org/10.1136/archdischild-2011-300585
- Robertson, M.M., Eapen, V., &Cavanna, A. E. (2009). The international prevalence, epidemiology, and clinical phenomenology of Tourette syndrome: A cross-cultural perspective. Journal of Psychosomatic Research, 67(6), 475-483. http://dx.doi.org/10.1016/j.jpsychores.2009.07.010
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- Accademia dellaCrusca(27May2017).http://www.accademiadellacrusca.it/it/link-utili/dizionari-sincronici
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- Robertson, M.M. (2000). Tourette syndrome, associated conditions and the complexities of treatment. Brain, 123(3), 425-462. http://dx.doi.org/10.1093/brain/123.3.425
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- Freeman, R.D., Zinner, S.H., Muller-Vahl, K.R., Fast, D.K., Burd, L.J., Kano, Y., Rothenberger, A., Roessner, V., Kerbeshian, J., Stern, J.S., Jankovic, J., Loughin, T., Janik, P., Shady, G., Robertson, M.M., Lang, A.E., Budman, C., Magor, A., Bruun, R., and Berlin, C.M. Jr. (2009) Coprophenomena in Tourettesyndrome. Med. ChildNeurol,51: 218–227.DOI:10.1111/j.1469-8749.2008.03135.x
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- Comisión Europea (27May2017). Las enfermedades raras: un desafío para Europa. http://ec.europa.eu/health/ph_threats/non_com/docs/raredis_comm_es.pdf
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