Tourette's syndrome - a review

Tourette's syndrome (TS) is a neuropsychiatric disorder characterised by the occurrence of chronic motor and vocal tics that usually begin in childhood. A prevalence of 4-5/10.000 individuals is estimated. Tourette's syndrome patients frequently show comorbidity with other psychiatric disorders such as obsessive compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD), anxiety, and affective disorders. Some forms of OCD seem to share a common genetic etiology with TS and to be a facultative part of the TS phenotypic spectrum. Based on MRI, positron emission tomography (PET), and single photon emission computed tomography (SPECT), data alterations in the cortico-striato-pallido-thalamo-cortical functional systems have been discussed. Within these systems, dopaminergic neurotransmission is thought to play an important role in the pathophysiology of TS. Autoimmunological mechanisms seem to be important in some subtypes of TS and OCD that are triggered or exacerbated by infections with hemolytic streptococci. In these cases, immune modulatory therapy proved to be efficient. To date, there is no established treatment regimen for TS. The medications used most frequently are antipsychotics.     

Tic disorders: neural circuits, neurochemistry, and neuroimmunology

The neuroanatomy and neurochemistry underlying tic disorders are thought to involve corticostriatothalamocortical circuits and dysregulation of their component neurotransmitter systems. Tourette syndrome is a tic disorder that begins in childhood and follows a waxing and waning course of tic severity. Although it is generally believed to have a genetic component, its etiology has not been fully elucidated. The clinical entity pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection (PANDAS) has led some to suggest that the pathophysiology of tics in some individuals might involve a postinfectious autoimmune component. We review the neural circuits and neurochemistry of Tourette syndrome and evaluate the evidence for and against a role for autoimmunity in the expression of tics.     

Promising avenues of therapeutics for bipolar illness

Basic scientific advances in understanding the neuropsychobiology of bipolar disorder have given us a multitude of opportunities to explore and exploit new avenues of therapeutics. Pharmacotherapeutic approaches include: neuropeptides (agonists such as thyrotropin-releasing hormone and antagonists such as corticotropin-releasing hormone), neurotrophic factors (especially brain-derived neurotrophic factor), and glutamatergic mechanisms (such as riluzole, ketamine, and antagonists of the NR-2B subunit of the glutamate receptor). Physiological interventions that would offer alternatives to electroconvulsive therapy include: repeated transcranial magnetic stimulation, especially at more intense stimulation parameters; magnetic stimulation therapy (seizures induced more focally by magnetic rather than electrical stimulation with resulting reduced meaning loss); vagal nerve stimulation, and deep brain stimulation. However, these, as well as the panoply of existing treatments, require further intensive investigation to place each of them in the proper therapeutic sequence and combination for the individual patient, based on development of better clinical and biological predictors of response. Large clinical trial networks and development of systematic research in clinical practice settings, such as that featured by the National Cancer Institute for cancer chemotherapy, would greatly accelerate the progress in incorporating new, as well as existing, agents into the best treatment strategies. The bipolar disorders, which are increasingly recognized as complex, highly comorbid conditions with a high morbidity and mortality, of which the majority start in childhood and adolescence, are not likely to respond completely to any single new treatment agent, and new public health initiatives and research strategies are needed as much as any new single treatment advance.     

Behavioral disturbances in Parkinson's disease

Treatment of Parkinson's disease (PD) is complex and often involves addressing behavioral changes in addition to the movement disorder. Patients with PD are susceptible to any psychiatric condition seen in the general population; some disorders, such as depression and anxiety, may result from PD-related neuropathological changes. Medicationrelated hallucinations are seen in many PD patients who are treated with dopaminergic agents for motor symptoms. Cognitive impairment is also seen and can be multifactorial. Treatment of behavioral symptoms in PD can greatly improve patients" overall function and quality of life. As surgical interventions to treat motor symptoms, such as deep brain stimulation of the subthalamic nucleus of the substantia nigra, become more prevalent, the behavioral effects of these procedures must also be addressed.     

Treatment of Tourette Syndrome

Tourette’s syndrome (TS) consists of chronic motor and phonic tics and characteristically begins in childhood. The tics can be disabling and commonly associated behavioral comorbities such as attention deficit hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD), can also cause problems in daily functioning. The underlying etiology and neurobiology of TS remain unknown although genetic factors appear to be important, cortical control of basal ganglia motor function appears to be disturbed and neurochemical abnormalities, particularly involving dopamine neurotransmission, are likely present. The treatment of TS involves appropriate education and support. Tics can be treated with habit reversal cognitive behavioral therapy, medications (most commonly alpha agonists and antipsychotics), local intramuscular injections of botulinum toxin and some severe, refractory cases have responded to deep brain stimulation surgery (DBS). It is important to appropriately diagnose and treat comorbid behavioral disorders that are disrupting function. OCD can be treated with cognitive behavioral therapy, selective serotonin reuptake inhibitors, and atypical antipsychotics. DBS has become a treatment option for patients with disabling OCD despite other therapies. ADHD is treated with appropriate classroom accommodations, behavioral therapy, alpha agonists, atomoxetine or methylphenidate-containing stimulant drugs.     

PANDAS: current status and directions for research

The recognition of the five criteria for PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections) by Swedo et al established a homogenous subgroup of children with childhood onset obsessive-compulsive disorder (OCD) and/or tic disorders. The five clinical characteristics that define the PANDAS subgroup are the presence of OCD and/or tic disorder, prepubertal age of onset, abrupt onset and relapsing-remitting symptom course, association with neurological abnormalities during exacerbations (adventitious movements or motoric hyperactivity), and a temporal association between symptom exacerbations and a Group-A beta-hemolytic streptococcal (GAS) infection. These five criteria have been used for the purpose of systematic research on the phenomenology and unique therapies for the PANDAS subgroup as well as studies of the pathophysiology of post-streptococcal OCD and tic disorders. The etiology of OCD and tics in the PANDAS subgroup is unknown, but is theorized to occur as a result of post-streptococcal autoimmunity in a manner similar to that of Sydenham's chorea. The working hypothesis for the pathophysiology begins with a GAS infection in a susceptible host that incites the production of antibodies to GAS that crossreact with the cellular components of the basal ganglia, particularly in the caudate nucleus and putamen. The obsessions, compulsions, tics, and other neuropsychiatric symptoms seen in these children are postulated to arise from an interaction of these antibodies with neurons of the basal ganglia.     

Autoimmune neuropsychiatric disorders associated with streptococcal infection: Sydenham chorea, PANDAS, and PANDAS variants

Streptococcal infection in children is usually benign and self-limited. In a small percentage of children, prominent neurologic and/or psychiatric sequelae can occur. Sydenham chorea is the best defined and best recognized. PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection) is a well-defined syndrome in which tics (motor and/or vocal) and/or obsessive-compulsive disorder consistently exacerbate in temporal correlation to a group A beta-hemolytic streptococcal infection. PANDAS constitutes a subset of children with tics, Tourette syndrome, and obsessive-compulsive disorder. In addition to strictly defined PANDAS, we and others have recognized several PANDAS variants, including adult-onset variant, a dystonic variant, a myoclonic variant, and a "chronic" PANDAS variant. The nosology and classification of these entities are rapidly evolving. The recognition that some pediatric neurobehavioral syndromes have infectious and/or immunologic triggers points to important new avenues of disease treatment. In this review, we summarize this complex and rapidly evolving area of clinical research.     

Tourette's syndrome in adults

Tourette's syndrome (TS) is defined as motor and phonic tics starting before age 18 years, and therefore most studies have focused on childhood TS, whereas the disorder in adults has not been well characterized. We reviewed medical records of all new TS patients referred to our Movement Disorders Clinic over the past 5 years, 19 years or older on initial evaluation and compared them with 100 TS patients 18 years or younger. The mean age at initial visit of 43 adult TS patients was 58.8 ± 6.7 years, whereas the mean age at initial visit of children with TS was 12.9 ± 2.0 years. Of the adult TS patients, 35 (81.4%) had a history of tics with onset before the age of 18 years (mean age at onset: 8.5 ± 3.4 years), with 8 (18.6%) reporting first occurrence of tics after the age of 18 years (mean age at onset: 37.8 ± 13.2 years). Only two (4.7%) patients reported tic onset after the age of 50 years. Adult patients with TS had significantly more facial and truncal tics, and a greater prevalence of substance abuse and mood disorders, but fewer phonic tics, and lower rates of attention‐deficit hyperactivity disorder and oppositional behavior than children with TS. Adult TS largely represents reemergence or exacerbation of childhood‐onset TS. During the course of TS, phonic and complex motor tics, self‐injurious behaviors, and attention‐deficit hyperactivity disorder tend to improve, but facial, neck, and trunk tics dominate the adult TS phenotype. In addition, adults with TS are more likely to exhibit substance abuse and mood disorders compared with children with TS. © 2010 Movement Disorder Society     

Tic disorders: from pathophysiology to treatment

Tic disorders are stereotypic behaviours,more frequent than once believed, and therefore likely to be encountered by primary care physicians. Tics usually begin in childhood and are the clinical hallmark of Tourette Syndrome (TS), the most common cause of tics. TS is a relatively common neurobehavioural disorder with a spectrum of manifestations that wax and wane during its natural course. The pathophysiology of tics, at molecular and cellular level, is still unknown,whereas structural and functional neuroimaging studies have shown the involvement of the basal ganglia and related cortico–striato–thalamo–cortical circuits, and the dopaminergic neuronal system. Moreover, TS has a strong genetic background. The management of TS is often complicated by the presence of attention–deficit/hyperactivity disorder, obsessivecompulsive disorder, and other behaviour disorders. The correct diagnosis is a fundamental step for a proper management of these disorders, and a multimodal treatment is usually indicated. This approach includes educational and supportive interventions, as well as pharmacological treatments when tics are at their worst.     

Tics and its disorders

Tourette syndrome (TS) is familial neuropsychiatric disorder that is characterized by motor and phonic tics that begin in childhood. Once thought of as a rare and debilitating disorder, in the last decade new scientific knowledge suggests that TS and related tic disorders are more common and less debilitating for the majority of individuals. Evidence points toward a spectrum of TS symptomatology that extends beyond the tics disorder to probably include obsessive-compulsive disorder, attention deficit hyperactivity disorder, and mood disorders. Tourette syndrome and its differential diagnosis are discussed in this article with a focus on new developments in classification, etiology, epidemiology, genetics, pathophysiology, and clinical management.     

Sleep and anxiety disorders

Sleep disturbances-particularly insomnia - are highly prevalent in anxiety disorders and complaints such as insomnia or nightmares have even been incorporated in some anxiety disorder definitions, such as generalized anxiety disorder and posttraumatic stress disorder. In the first part of this review, the relationship between sleep and anxiety is discussed in terms of adaptive response to stress. Recent studies suggested that the corticotropin-releasing hormone system and the locus ceruleus-autonomic nervous system may play major roles in the arousal response to stress. It has been suggested that these systems may be particularly vulnerable to prolonged or repeated stress, further leading to a dysfunctional arousal state and pathological anxiety states, Polysomnographic studies documented limited alteration of sleep in anxiety disorders. There is some indication for alteration in sleep maintenance in generalized anxiety disorder and for both sleep initiation and maintenance in panic disorder; no clear picture emerges for obsessive-compulsive disorder or posttraumatic stress disorder. Finally, an unequivocal sleep architecture profile that could specifically relate to a particular anxiety disorder could not be evidenced; in contrast, conflicting results are often found for the same disorder. Discrepancies between studies could have been related to illness severity, diagnostic comorbidity, and duration of illness. A brief treatment approach for each anxiety disorder is also suggested with a special focus on sleep.     

The epidemiology of anxiety disorders: a review

Epidemiological studies show that anxiety disorders are highly prevalent and an important cause of functional impairment; they constitute the most frequent menial disorders in the community. Phobias are the most common with the highest rates for simple phobia and agoraphobia. Panic disorder (PD) and obsessive-compulsive disorder (OCD) are less frequent (2% lifetime prevalence), and there are discordant results for social phobia (SP) (2%-16%) and generalized anxiety disorder (GAD) (3%-30%). These studies underline the importance of an accurate definition of disorders using unambiguous diagnostic and assessment criteria. The boundaries between anxiety disorders are often ill defined and cases may vary widely according to the definition applied. Simple phobia, agoraphobia, and GAD are more common in vmrnen, while there is no gender différence for SP, PD, and OCD, Anxiety disorders are more common in separated, divorced, and widowed subjects; their prevalence is highest in subjects aged 25 to 44 years and lowest in subjects aged >65 years. The age of onset of the different types of anxiety disorders varies widely: phobic disorders begin early in life, whereas PD occurs in young adulthood. Clinical - rather than epidemiological - studies have examined risk factors such as life events, childhood experiences, and familial factors. Anxiety disorders have a chronic and persistent course, and are frequently comorbid with other anxiety disorders, depressive disorders, and substance abuse. Anxiety disorders most frequently precede depressive disorders or substance abuse, Comorbid diagnoses may influence risk factors like functional impairment and quality of life. It remains unclear whether certain anxiety disorders (eg, PD) are risk factors for suicide. The comorbidity of anxiety disorders has important implications for assessment and treatment and the risk factors should be explored. The etiology, natural history, and outcome of these disorders need to be further addressed in epidemiological studies.     

A lifespan view of anxiety disorders

Neurodevelopmental changes over the lifespan, from childhood through adulthood into old age, have important implications for the onset, presentation, course, and treatment of anxiety disorders. This article presents data on anxiety disorders as they appear in older adults, as compared with earlier in life. In this article, we focus on aging-related changes in the epidemiology, presentation, and treatment of anxiety disorders. Also, this article describes some of the gaps and limitations in our understanding and suggests research directions that may elucidate the mechanisms of anxiety disorder development later in life. Finally we describe optimal management of anxiety disorders across the lifespan, in "eight simple steps" for practitioners.     

Childhood trauma and psychosis - what is the evidence?

In the last decade, a substantial number of population-based studies have suggested that childhood trauma is a risk factor for psychosis. In several studies, the effects held after adjusting for a wide range of potentially confounding variables, including genetic liability for psychosis. Less is known about the mechanisms underlying the association between childhood trauma and psychosis. Possible pathways include relationships between negative perceptions of the self, negative affect, and psychotic symptoms, as well as biological mechanisms such as dysregulated cortisol and increased sensitivity to stress. Psychotic patients with a history of childhood trauma tend to present with a variety of additional problems, including post-traumatic stress disorder, greater substance abuse, higher levels of depression and anxiety, and more frequent suicide attempts. Initial studies suggest that trauma-specific treatments are as beneficial for these patients as for other diagnostic groups.     

Inhibition of the reward system by antipsychotic treatment

The mesolimbic dopaminergic reward system is responsible for the negative affective symptomatology of schizophrenia, which may be related to a low dopamine tonus within the ventral striatum. The monetary incentive delay (MID) task can be used to study the response of the ventral striatum to incentive stimuli. We show that activation of the ventral striatum is low in patients with schizophrenia, and that this low activation is related to primary and secondary negative symptoms induced by neuroleptics, also known as antipsychotics. Switching from first-(typical) to second-generation (atypical) antipsychotics increased activation of the ventral striatum due to less blocking of dopamine D2 receptors. This and similar studies show that functional magnetic resonance imaging (fMRI) tasks are suitable to investigate important aspects of antipsychotic mechanisms.     

Obsessive-compulsive spectrum disorders

The obsessive-compulsive spectrum is an important concept referring to a number of disorders drawn from several diagnostic categories that share core obsessive-compulsive features. These disorders can be grouped by the focus of their symptoms: bodily preoccupation, impulse control, or neurological disorders. Although the disorders are clearly distinct from one another, they have intriguing similarities in phenomenology, etiology, pathophysiology, patient characteristics, and treatment response. In combination with the knowledge gained through many years of research on obsessive-compulsive disorder (OCD), the concept of a spectrum has generated much fruitful research on the spectrum disorders. It has become apparent that these disorders can also be viewed as being on a continuum of compulsivity to impulsivity, characterized by harm avoidance at the compulsive end and risk seeking at the impulsive end. The compulsive and impulsive disorders differ in systematic ways that are just beginning to be understood. Here, we review these concepts and several representative obsessive-compulsive spectrum disorders including both compulsive and impulsive disorders, as well as the three different symptom clusters: OCD, body dysmorphic disorder, pathological gambling, sexual compulsivity, and autism spectrum disorders.     

Differing response to antipsychotic therapy in schizophrenia: pharmacogenomic aspects

Treatment-resistance in schizophrenia remains a public health problem: about 20% to 30% of patients do not respond to antipsychotic therapy. Clozapine has been shown to be effective in about one-third of patients, but the medical risks and weekly blood tests limit its broad application. While the heterogeneity of the disease and the duration of untreated psychosis are important, pharmacogenomic aspects must also be considered. Pharmacogenomic investigations offer the opportunity to individualize antipsychotic therapy according to the growing knowledge of the function and effect of the genetic polymorphisms that affect the pharmacokinetics and pharmacodynamics of antipsychotics. On the pharmacokinetic level, polymorphic phase I and II drug-metabolizing enzymes and transport proteins affect drug concentration at the target structure. The cytochrome P450 enzymes, N-acetyltransferase, and multidrug resistance protein (MDR1) particularly influence this parameter. Genetic alterations affecting drug pharmacodynamic properties have an impact on therapeutic outcome that is generally independent of the applied dosage regimen. A combined analysis of genetic polymorphisms in the dopaminergic and serotonergic receptors, neurotransmitter transporters, and other target structures involved in psychiatric disorders is already a powerful predictor of therapeutic outcome. An understanding of other factors influencing gene expression and protein production will facilitate individualized therapy in the future.     

Gilles de la Tourette's syndrome

Tourette's syndrome (TS) is a childhood onset neurological disorder characterized by motor and vocal tics. It may be associated with a number of co-morbidities including attention deficit hyperactivity disorder, obsessive compulsive symptomatology, and behaviour disorders. Prevalence of TS is higher than previously thought, and may be present in up to 2% of the population. Tourette's syndrome has a significant genetic component. Inheritance may involve several mechanisms including autosomal dominant, bilinear, or polygenic mechanisms. Pathophysiology is still unknown, although is thought to involve striatocortical circuits. Treatment begins with modification of the work and home environment. For more severe cases, medications such as tetrabenazine and neuroleptics may be helpful. Treatment of co-morbidities needs to be considered, as these may result in moredisability than the tics themselves.     

Antineuronal antibodies in a group of children with obsessive-compulsive disorder and Tourette syndrome

An autoimmune hypothesis has been suggested for early onset obsessive-compulsive disorder and Tourette syndrome. The term: Paediatric autoimmune neuropsychiatric disorders associated with streptococcal infection (PANDAS) has been proposed as an aetiological subtype of OCD and TS, related to a Group A beta haemolytic streptococcal (GABHS) infection that triggers an autoimmune response. Antineural antibodies have been studied and found in the sera of some patients with these disorders, and they are thought to cross-react with streptococcal and basal ganglia antigens. The present study included 32 prepubertal-onset OCD patients, 21 with TS diagnosis (some of them meeting criteria for PANDAS) and 19 normal children, all aged between 9 and 17 years. Antibodies were assayed by immunohistochemistry and immunoblot. Special attention was paid to the methodology and a high serum dilution was used to minimize non-specific binding. No anti-basal ganglia antibodies were detected by immunohistochemistry in any of the samples. Two proteins, with approximate molecular weights of 86 kDa and 55 kDa, were found in sera from 7 patients. Though the study supports the hypothesis of an autoimmune process underlying OCD or TS in some patients, further research is needed.     

Mechanisms of change in psychosocial interventions for autism spectrum disorders

Research into psychosocial interventions (particularly cognitive-behavior therapies and social skills training) for social-communication deficits among individuals with autism spectrum disorder (ASD) has proliferated over the past decade. While this research has provided some empirical support for the efficacy of these interventions, little work has begun to elucidate therapeutic mechanisms—the when, why, how, for whom, and under what conditions an intervention may produce change, identification of mechanisms underlying these effects should help advance ASD intervention research. This article describes methods for assessing such mechanisms (ie, mediators and moderators) and presents promising candidates for common mechanisms impacting treatment response: behavior modification, therapeutic relationship, social knowledge, social motivation, social information processing, executive functioning, and internalizing comorbidities. Finally, future directions are discussed as a program of psychosocial intervention research designed to identify predictors of individual differences in treatment response (including biomarkers), isolate active therapeutic ingredients, and promote dissemination of optimized interventions.