LETTERS TO THE EDITORS
On Secondary Tics and Tourettism
Dear Editor,
We kindly thank Drs. Hounie and Sampaio for their interest in our recent paper on "Secondary tics and tourettism".1 As they mentioned, our sample of 155 patients with tics and co-existent disorders included 101 (65.1%) male and 54 female (34.8%) patients. Although a higher prevalence of Tourette syndrome (TS) in males has been well recognized,2 we consider the higher proportion of male patients in our population of patients with secondary tics coincidental and do not believe that our study provides sufficient data to point to a greater susceptibility of males to develop secondary tics. Nonetheless, we believe that the study of risk factors associated with the development of secondary tics, including gender, may play an important role in understanding the physiopathology of tics and TS.
We would also like to clarify that the 16 (10.3%) patients found to develop psychogenic tics in our series of 155 patients were diagnosed using previously published criteria.3 In all our patients, the existence of tics could not be directly attributed to a lesion or dysfunction of the nervous system, and was derived in all cases from psychological or psychiatric causes. We understand Drs. Hounie and Sampaio's concern of the current use of diagnostic criteria for all psychogenic movement disorders, and encourage the scientific community to use the available criteria3-4 as a guide to the clinical assessment of their patients.
Nicte I Mejia, Joseph Jankovic
Parkinson's Disease Center and Movement Disorders
Clinic, Department of Neurology, Baylor College of
Medicine, Houston, Texas, USA
References
1. Mejia NI, Jankovic J. Tiques secundários e touretismo. Rev Bras Psiquiatr. 2005;27(1):11-7.
2. Freeman RD, Fast DK, Burd L, Kerbeshian J, Robertson MM, Sandor P. An international perspective on Tourette syndrome: selected findings from 3,500 individuals in 22 countries. Dev Med Child Neurol. 2000;42(7):436-47.
3. Thomas M, Jankovic J. Psychogenic movement disorders: diagnosis and management. CNS Drugs. 2004;18(7):437-52.
4. Fahn S, Williams DT. Psychogenic dystonia. Adv Neurol. 1998;50:431-55.
Publication Dates
-
Publication in this collection
21 Nov 2005 -
Date of issue
June 2005
