Many of the symptoms associated with GTS are believed to be aggravated by anxiety, stress, tiredness, worry, excitement. Whilst activities like sleep, relaxation, or concentrating on an enjoyable task will often alleviate the symptoms temporarily.
Characteristically, over a GTS patients lifetime the types of tic's they experience will change, old tic behaviour will be replace by a new one. Despite the fact that GTS has been classified as an "involuntary" movement disorder often a patient can suppress the symptoms during an interview or while at school. This ability to suppress the tic's at the expense of inner tension is a characteristic of the disorder.
ASSOCIATED FEATURES
Other associated behaviours which have have been reported to occur in patients with GTS can include one or more of the following; Attention Deficit Disorders and hyperactivity (ADHD), impulsivity, irritability, aggressiveness, immaturity, anxiety, depression, and in rare cases self injurious behaviour. Other psychiatric disorders include, habit disorders, phobic gestures and in some cases obsessional and compulsive behaviours (OCD) have been reported, these include counting ritual, concern with symmetry, elaborate checking routines, touching and arranging. It is believed that some of these associated disorders may be an integral part of GTS, but others may be reactions to social stresses associated with coping with a chronic disorder.
Finally, normal intelligence has been found in most of GTS patients, however, a discrepancy has been found between verbal and performance IQ scores (Shapiro et al 1978).
FAMILY PSYCHOPATHOLOGY
It has been argued that there is a clear association with GTS and OCD, recent findings have reported a high incidence of OCD in the first degree relatives of GTS patients, (Montgomery et al 1982) which suggests that GTS and some types of OCD may be aetiologically or genetically related.
Further studies into the family history of GTS patients have reported to find some evidence of tic's and GTS plus other forms of Psychiatric illnesses especially unipolor depression and OCD in relatives of Tourette's patients. Although the incidence of these appear to be very small, Hajal & Leach (1981) suggest that relatives are very reluctant to reveal their own history of tic's or psychiatric problems and therefore studies of family prevalence may represent an underestimation.
Genetics
Many recent investigations have addressed the question of a genetic predisposition in GTS and at the present time the evidence is mostly in support of a major autosomal dominant gene, but to date no positive results have been published. However research into a possible genetic link is continuing in the UK the USA and the Netherlands.
DIAGNOSIS
In the past a problem with diagnosis has arisen because some clinicians mistakenly believed that the symptoms exhibited by GTS patients have to be of a very severe nature, or that swearing and shouting obscenities is an essential feature of the illness. But for every severe case of head jerks, noises and swearing there are many subtle cases which may go unnoticed.
Many of the GTS patients are referred to clinics having been misdiagnosed as having behavioural problems, personality disorders or even epilepsy. One of the problems clinicians are faced with when making a diagnosis is having to differentiate between GTS and tic's in childhood which commence between the ages of 5 and 10 years but may remit spontaneously or improve with age. Other conditions which have to be considered in the differential diagnosis of GTS include sydenham - chorea, spasmodic torticollis, Wilson's disease, dystonia muscularum deformans, encephalitis lethargica, Huntington's chorea, plus several other conditions. If in any doubt about diagnosis the best course of action for any clinician would be to refer the patient to a consultant or a centre which specialises in movement and GTS.
PROGNOSIS
When Gilles De La Tourette's (1885, 1899) first reported cases of fully developed symptoms of the syndrome the prognosis was not very good, with the majority of cases requiring long-term hospitalisation. However, recent reports suggest a more favourable outcome. For example, Corbett et al (1969) studied 73 GTS patients referred to the Maudsley hospital. These patients were followed up from 1 - 18 years after their first attendance. It was reported that none of the patients showed any signs of deterioration, 6% were unchanged, half had improved to some degree and two-thirds of these were completely recovered. However, it appears that reports of complete remission of GTS is the exception. Despite a reduction in the severity of the symptoms in adulthood most of the literature, case reports and clinical experience suggest that GTS is a life long illness.
WHAT MIGHT BE THE CAUSE OF TOURETTE'S SYNDROME?
Since tic's are a characteristic feature of GTS scientists have chosen to look at certain areas of the brain involved in movement. In recent years attention has focused on a set of structures lying deep within the brain which are collectively known as the Basel Ganglia. These structures appear to be involved in the initiation and coordination of body movements and have been implicated in other movement disorders such as Parkinson's disease. They are connected via complex sets of circuits to other regions of the brain involved in sensation and movement.
Studies of the electrical activity within the brain have as yet revealed no consistent picture of any large scale abnormalities. However, the leading theory today about the cause of GTS lies with the naturally occurring chemicals in the brain, one of which is called Dopamine.
Dopamine is produced in the region of the mid-brain called the substantia nigra, neurons use Dopamine as a transmitter. Neurotransmitters are important in the transmission of messages between one brain cell and another. Dopamine is involved in the regulation of emotional responses and in the subconscious movement of skeletal muscles. Therefore it is believed that Dopamine is the most important neurotransmitter which is not working properly, but it is also likely that there may be other other such chemicals involved in causing the symptoms of GTS.
Another is Serotonin which is produced mainly in the brain stem but exerts it's effect in wide spread areas of the Hypothalamus and Cerebral Cortex, it is involved in sensory perception and the control of moods both of which are effected in GTS. Then there is Noradenealin which is also produced in the brain stem, cerebral cortex, hypothalamus, and cerebellum and acts in the same way as Serotonin. It may be related to arousal and mood which influences the severity of the tics.
Finally, there are also substances called Opioids which are found in various parts of the brain e.g brain stem, hypothalamus and thalamus, these play a role in emotion and the perception of pain, they have recently been implicated in GTS. The possible involvement of several neural transmitters in GTS arises because there are other features associated with the condition.
POSSIBLE TREATMENTS
For many of the sufferers of GTS a clinical diagnosis, learning that there is a name for the illness they are suffering from plus an improved understanding of the disorder is often sufficient to help the individual adapt and cope with their problems without the use of medication. Therefore, for many of the patients who suffer from a mild form of GTS a clinician might only have to see the patient once or twice more after the initial appointment to give the patient some feedback about the investigations that they had performed; and to give further information about the condition both to the patient, their relatives and perhaps advice to teachers about how to cope with a child who has been diagnosed as being a GTS sufferer.
However, there are those patients for whom the symptoms of GTS are quite disabling and who may also be suffering from associated features like OCD who may require more specialist intervention and medication.
Chemotherapy is at present the mainstay of treatment for the motor and vocal tic symptoms of GTS. Drugs which act as dopamine blockers such as, haloperidol, pimozide, sulpiride are again prescribed for the motor and vocal tic's. Clonidine and serotonin are antidepressant drugs which are often given to children who suffer from ADHD as well as GTS. Others include, fluoxetine, clomipramine, fluvoamine, paroxetine for patients whose symptoms are accompanied by OCD.
All of the drugs listed above have possible long and short term side effects therefore when prescribing drugs such as these a balance must be struck between the beneficial effect of the drugs and the side effects that accompany them. Also as with other drugs the dosage always has to be tailored to the needs of the individual.
But there are other approaches to dealing with the impact of GTS. Behavioural therapy has helped both individuals with GTS and their families to cope with the social and psychological problems that inevitably arise. In collaboration with the therapist they can develop strategies for coping with specific aspects or accompanying features of GTS, such as OCD. For instance, techniques which reduce the anxiety levels like using anxiety check lists to rate their anxiety and learning relaxation techniques to reduce their anxiety levels. Reactive intervention techniques could be used to reduce compulsive behaviour in children. Redirective behaviour techniques can be taught to the GTS patient's to try to help them to overcome their habit of shouting obscenities.
CONCLUSION
Although I started this essay by saying that 'not many people have heard of GTS' it would appear that GTS is no longer the rarity it was once considered to be and although it's still not common it's believed that the prevalence of the syndrome is far higher than the figures quoted from the reported cases in Britain.
Recent research has indicated that genetic factors might be involved and although the precise aetiology is unknown several possible anatomical sites and neurotransmitter abnormalities have been implicated as a possible cause of GTS.
Finally, in reviewing the contents of this essay it appears that GTS brings together many strands of understanding, it's clinical aspect, for instance, brain biochemistry, the use of drugs and lastly behavioural approaches to help control some of the features associated with GTS. However, for the person who has to live with GTS and their families it can be a life long companion with, as yet, no foreseeable cure.
BIBLIOGRAPHY
American Psychiatric Association (1980) Diagnostic & Statistical Manual of Mental Disorders. DSM-III (3rd edition) American Psychiatric Association; Washington.
Cooper, J.R., Bloom, F.E. & Roth, R.H. (1986) The Biochemical Basis of Neuropharmacology. University Press: Oxford.
Halgin, R.P. & Whitbourne, S.K. (1993) Abnormal Psychology. Harcourt Brace Jovanovich College Inc.: U.S.A.
Gomez, J. (1991) Psychological & Psychiatric Problems in Men. Routledge; London.
Rutter, M. & Hersov, L. (1985) Child & Adolescent Psychiatry, Modern Approaches. 2nd Edition. Blackwell Scientific Publications;London.
Robertson, M.M. (1989) The Gilles de la Tourette Syndrome: The current status. British Journal of Psychiatry, 154. pp 147-169.
Thompson, R.F. (1985) The Brain. W.H. Freeman and Company; New York.
REFERENCES
Abuzzahab, F.S. & Anderson, F.O. (1976) Gilles de la Tourette's Syndrome. Vol.1. Mason, St. Paul; Minnesota.
Corbett, J.A., Matthews, A.M., Connell, P.H. & Shapiro, D.A. (1969) Tic's & Gilles de la Tourette's Syndrome: a follow-up study and critical review. British Journal of Psychiatry 115, pp 1229-1241.
Eldridge, R., Sweet, R., Lake, C.R., Ziegler, M. & Shapiro, A.K. (1977) Gilles de la Tourette's syndrome: Clinical,genetic,psychologic and biochemical aspects of 21 selected families. Neurology 27, pp 115-124.
Golden, G.S.(1977) Tourette's syndrome: the paediatric perspective. American Journal Dis. Child. 131, pp 531-534.
Golden, G.S. (1978) Tic's and Tourette's: a continuum of symptoms. Annals of Neurology 4, pp 145-148.
Hajal F. & Leach , A.M. (1981) Familial aspects of Gilles de la Tourette's syndrome. American Journal of Psychiatry. 138, pp 90-92.
Montgomery. M.A., Clayton, P.J. & Friedhoff, A.J. (1982) Psychiatric illness in Tourette syndrome patients and first degree relatives. In Friedhoff A.J. & Chase, T.N. (eds) Gilles de la Tourette's syndrome, pp 335-340. Raven Press, New York.
Shapiro, A.K., Shapiro,E.S., Bruun, R.D. & Sweet, T.R.D. (1978) Gilles de la Tourette syndrome. Raven Press; New York.
Wassman, E.R., Elderidge, R., Abuzzahab, F.S. & Nee, L. (1978) Gilles de la Tourette syndrome: Clinical and genetic studies in a midwestern city. Neurology 28, pp 304-307
