Tourette's syndrome in Taiwan: an epidemiological study of tic disorders in an elementary school at Taipei County

We've all been wrong about provisional tic disorder

BACKGROUND

Provisional Tic Disorder (PTD) is common in childhood. The received wisdom among clinicians is that PTD is short-lived and mild, with at most a few tics, and rarely includes complex tics, premonitory phenomena or comorbid illnesses. However, such conclusions come from clinical experience, with biased ascertainment and limited follow-up.

METHODS

Prospective study of 89 children with tics starting 0-9 months ago (median 4 months), fewer than half from clinical sources. Follow-up at 12 (± 24, 36, 48) months after the first tic.

RESULTS

At study entry, many children had ADHD (39), an anxiety disorder (27), OCD (9) or enuresis (17). All had at least two current tics, with a mean total since onset of 6.9 motor and 2.0 phonic tics. Forty-one had experienced a complex tic, and 69 could suppress some tics. Tics were clinically meaningful: 64 had tics severe enough for a clinical trial, and 76 families sought medical attention for the tics. At 12 months, 79 returned, and 78 still had tics. Of these, 29 manifested no tics during history and extended examination, but only via audio-visual monitoring when the child was seated alone. Only 12/70 now had plans to see a doctor for tics. Most who returned at 2-4 years still had tics known to the child and family, but medical impact was low.

CONCLUSIONS

Our results do not contradict previous data, but overturn clinical lore. The data strongly argue against the longstanding but arbitrary tradition of separating tic disorders into recent-onset versus chronic.

Psychosocial experiences in youth with Tourette syndrome: a systematic review and meta-synthesis

Suffering from Tourette syndrome (TS) disrupts the daily lives and interpersonal relationships of patients. The psychosocial experiences of young people with TS are not yet clear. The aim of the systematic review is to identify and synthesize the psychosocial experiences of young people with TS. A meta-synthesis was conducted. PubMed, EMBASE, Cumulative Index to Nursing and Allied Health Literature, Web of Science, and Chinese Electronic Periodical Services databases were searched for articles published from their inception to February 2023. This review followed the Joanna Briggs Institute's Guidelines for Systematic Reviews according to a previously developed protocol. We used the confidence of synthesized qualitative findings (ConQual) approach to evaluate the credibility and dependability of the synthesized findings. This review included 12 qualitative studies from Western and Asian countries published between 2005 and 2019, representing 190 young people with TS. We identified five synthesized findings: affliction by intractable TS, TS was negatively perceived in the social and cultural context, self-adjustment in response to social interaction, response to receiving various interventions, and positivity in promoting self-acceptance. The ConQual grade for each generated synthesized finding ranged from low to moderate. The psychosocial experiences of youths living with TS are unique and are influenced by their interpersonal relationships, social context, and cultural framework. The findings recommend that healthcare providers assist young people in developing personalized symptom management strategies and provide guidance and care that meets the needs of each individual.

Treatment of Tourette syndrome by acupuncture combined with Chinese medicine based on syndrome differentiation: A review

Tourette syndrome (TS) is a chronic neurodevelopmental disorder characterized by involuntary motor and speech tics, which can greatly reduce the quality of life of patients. The pathophysiology of TS involves both genetic and environmental factors. Assessing TS pathogenesis is complex, and its underlying pathophysiology is not fully understood. It is gratifying that the research in the past 5 years has brought new research progress on the genetic, neurophysiological and brain network changes of TS. However, despite the progress of research, the treatment methods and drugs of modern medicine are still unsatisfactory, and it is difficult to achieve satisfactory results. Traditional Chinese medicine, as a part of complementary and alternative medicine, has unique efficacy in the treatment of TS, and the safety of its treatment is also worthy of attention. Based on the latest achievements in the pathophysiology of TS, this article will discuss the treatment of TS by acupuncture combined with medicine.

Prenatal and postnatal exposure to PM2 .5 and the risk of tic disorders

BACKGROUND

Tic disorders are common neurodevelopmental disorders during childhood. Whether prenatal and postnatal exposure to particulate matter with an aerodynamic diameter less than 2.5 μm (PM_2.5 ) plays a role in the development of tic disorders remains unexplored.

OBJECTIVES

To investigate the association of exposure between PM_2.5 during the pregnancy and infancy periods and the risk of tic disorders.

METHODS

This birth cohort study recruited singleton live births at term gestations in central Taiwan from the Taiwan Maternal and Child Health Database between 2004 and 2012 and followed up to the end of 2017. New cases of tic disorders were defined using the ICD-9-CM (307.2) and ICD-10-CM (F95), which include all tic spectrum disorders. We assigned daily PM_2.5 concentrations derived from a satellite-based model to individuals based on maternal residential addresses at delivery. We fit Cox proportional hazard model and distributed lag non-linear model to estimate the associations between PM_2.5 and tic disorders, with hazard ratio (HR) with 95% confidence interval (CI) as the effect measure.

RESULTS

Of the 309,376 singleton live births at term gestations, we identified 5902 (1.9%) tic disorder cases. The HR of tic disorders was positively associated with a 10 μg/m³ increase in PM_2.5 : during pregnancy HR 1.09, 95% CI 1.04, 1.15 and during infancy HR 1.12, 95% CI 1.06, 1.18. The vulnerable time window for infants with increased risk of tic disorders was 6-52 weeks after birth. We observed a nonlinear relationship between PM_2.5 and the risk of tic disorders, with exposure to PM_2.5 between 16 and 64 μg/m³ being associated with the risk of tic disorders. The association was restricted to Tourette's disorder group. Infant sex did not modify these associations.

CONCLUSIONS

Infants delivered at term and exposed to PM2.5 are associated with an increased risk of tic disorders (6-52 weeks). Further studies are needed to confirm these associations.

Systematic Review and Meta-Analysis of Tourette Syndrome Prevalence; 1986 to 2022

BACKGROUND

Tourette syndrome (TS) is a disorder characterized by a history of multiple motor tics and the emergence of at least one vocal tic during a period of the disorder. The current investigation sought to clarify the prevalence statistics for TS using a systematic review and meta-analysis.

METHODS

This systematic review and meta-analysis covered the period between 1986 and 2022. Embase, Scopus, PubMed, Web of Science, and Google Scholar were searched to locate articles pertinent to the study topic. The I² index was used to examine the heterogeneity of the studies, and a comprehensive meta-analysis was employed to analyze the data.

RESULTS

Ultimately, 30 studies (39 outcomes) were included in the meta-analysis and systematic review. The results showed the global prevalence of TS to be 0.5% (95% confidence interval [CI], 0.3% to 0.8%), with the highest rate of spread observed in the Americas at 0.6% (95% CI, 0.2% to 1.6 %). Analyzing the subgroups of the sample revealed that the highest prevalence was associated with the population of children and adolescents at 0.7% (95% CI, 0.4% to 1.4%) and males at 0.5% (95% CI, 0.2% to 1.0%).

CONCLUSIONS

This comprehensive review and meta-analysis revealed that the prevalence of TS worldwide is sufficiently high, such that attention of medical specialists and health policy makers is warranted.

Increased Risk of Tourette Syndrome with Leukotriene Modifier Use in Children with Allergic Diseases and Asthma: A Nationwide Population-Based Study

(1) Background: Cysteinyl leukotriene receptor antagonists (LTRAs), including montelukast and zafirlukast, are FDA-approved for treating pediatric asthma and allergic diseases. Tourette syndrome (TS), a common neuropsychiatric disorder in children, is associated with allergic diseases and asthma. In this study, we investigated the risk of TS following an LTRA prescription for pediatric allergic diseases. (2) Methods: Children younger than 18 years of age who were newly diagnosed with asthma, allergic rhinitis, or atopic dermatitis between 1 January 2005 and 31 December 2018 and who were registered in the Taiwan National Health Insurance Research Database, which comprises the medical records of nearly 23 million Taiwanese population, were enrolled. LTRA users were matched with randomly selected LTRA non-users by sex, age, asthma-diagnosis year, and urbanization level. In total, 26,984 participants with allergic disease and TS were enrolled and included in the Cox proportional hazards model analysis. (3) Results: Children with allergic disease and asthma treated with LTRAs had a higher risk for TS than LTRA non-users (adjusted hazard ratio 1.376 [95% CI: 1.232−1.536], p < 0.001). LTRA users had a significantly higher risk for TS than LTRA non-users with allergic disease. The cumulative incidence of TS was significantly higher in LTRA users than in non-users with allergic diseases and asthma (log-rank test, p < 0.0001). (4) Conclusion: A prescription of LTRAs, mainly montelukast, increased the risk of TS among children with asthma, allergic rhinitis, or atopic dermatitis. The mechanism underlying the neuropsychiatric effect of LTRAs needs further investigation.

Prevalence of nail biting and its chronological relationship with tics in child and adolescent outpatients with Tourette syndrome: a single-centre, retrospective observational study

OBJECTIVE

To evaluate the prevalence of nail biting in child and adolescent outpatients at a single institution and the chronological relationship between nail biting and tics in patients with Tourette syndrome (TS) with or without attention-deficit hyperactivity disorder (ADHD).

DESIGN

Retrospective observational study.

SETTING

Teaching hospital in Taiwan.

PARTICIPANTS

All participants were aged 4-18 years, including 535 patients with TS, 230 patients with provisional tic disorder and 1460 patients without neurological or psychiatric disorders (controls).

OUTCOME MEASURES

Presence of nail biting, starting age for nail biting and starting age for motor and/or vocal tics.

RESULTS

Nail biting was more commonly observed in patients with TS (56.6%) than in patients with provisional tic disorder (27.4%) or controls (15.0%), regardless of sex (all p<0.020). Nail biting was also more common in patients with TS with ADHD than in those without (75.0% vs 47.6%; p<0.001), but the starting age was significantly later in those with concomitant ADHD than without (5.3 vs 3.8 years; p<0.001). In patients with TS, the onset of nail biting occurred earlier than that of tics, regardless of ADHD status.

CONCLUSION

Nail biting was more prevalent and occurred earlier than tics in patients with TS, regardless of ADHD status, in the study population.

Incidence and prevalence of Tourette syndrome and chronic tic disorders in Taiwan: a nationwide population-based study

PURPOSE

The incidence of Tourette syndrome and chronic tic disorders has seldom been evaluated in Asia.

METHODS

Using the National Taiwan Insurance Research Database, the annual standardized incidence and prevalence of Tourette syndrome (TS) and chronic tic disorders were estimated from 2007 to 2015. The pre-existing comorbidity at disease diagnosis was also evaluated.

RESULTS

From 2007 to 2015, the age- and sex-standardized incidence increased from 5.34 (95% confidence interval [CI] 5.06-5.62) per 100,000 person-years to 6.87 (95% CI 6.53-7.21) per 100,000 person-years. In children and adolescents, the age- and sex-standardized incidence increased from 19.58 (95% CI 18.42-20.75) per 100,000 person-years to 31.79 (95% CI 30.09-33.49) per 100,000 person-years. In adults, the age- and sex-standardized incidence decreased from 2.01 (95% CI 1.79-2.23) per 100,000 person-years to 1.24 (95% CI 1.07-1.42) per 100,000 person-years. The incidence rate ratio (IRR) between males and females was 3.74 (95% CI 3.32-4.22). The age- and sex-standardized prevalence increased from 37.51 (95% CI 36.75-38.27) per 100,000 people in 2007 to 84.18 (95% CI 83.02-85.35) per 100,000 people in 2015. The rate risk (RR) between males and females was 3.65 (95% CI 3.53-3.78).

CONCLUSION

The annual incidence rates of TS and chronic tic disorders increased in childhood and adolescence but decreased in adulthood from 2007 to 2015. The prevalence rates increased over the same period.

Classification of tic disorders based on functional MRI by machine learning: a study protocol

INTRODUCTION

Tic disorder (TD) is a common neurodevelopmental disorder in children, and it can be categorised into three subtypes: provisional tic disorder (PTD), chronic motor or vocal TD (CMT or CVT), and Tourette syndrome (TS). An early diagnostic classification among these subtypes is not possible based on a new-onset tic symptom. Machine learning tools have been widely used for early diagnostic classification based on functional MRI (fMRI). However, few machine learning models have been built for the diagnostic classification of patients with TD. Therefore, in the present study, we will provide a study protocol that uses the machine learning model to make early classifications of the three different types of TD.

METHODS AND ANALYSIS

We planned to recruit 200 children aged 6-9 years with new-onset tic symptoms and 100 age-matched and sex-matched healthy controls under resting-state MRI scanning. Based on the neuroimaging data of resting-state fMRI, the support vector machine (SVM) model will be built. We planned to construct an SVM model based on functional connectivity for the early diagnosis classification of TD subtypes (including PTD, CMT/CVT, TS).

ETHICS AND DISSEMINATION

This study was approved by the ethics committee of Beijing Children's Hospital. The trial results will be submitted to peer-reviewed journals for publication.

TRIAL REGISTRATION NUMBER

ChiCTR2000033257.

Psychosocial stress, self-esteem, and social adjustment: A moderated mediation analysis in Taiwanese adolescents with Tourette syndrome

PURPOSE

Recent studies have shown that tics and related comorbidities can cause poorer social adjustment, lower self-esteem, and higher psychosocial stress among adolescents with Tourette syndrome. This study explored the role of self-esteem in mediating the relationship between psychosocial stress and social adjustment among adolescents with Tourette syndrome, and the role of comorbidities in moderating the relationship between self-esteem and social adjustment.

DESIGN AND METHODS

In this descriptive cross-sectional study, 118 Taiwanese adolescents with Tourette syndrome aged between 12 and 20 years old were recruited via convenience sampling. Their demographic information, Yale Global Tic Severity Scale, stress index for children and adolescents with Tourette syndrome, social adjustment scale for adolescents with Tourette syndrome, and Self-Esteem Scale results were collected. Moderated mediation analysis of the study data was performed with the Hayes's PROCESS macro.

RESULTS

Our results revealed that the self-esteem of adolescents with Tourette syndrome fully mediates the relationship between their psychosocial stress and social adjustment (B = -0.0703, 95% CI, [-0.0176, -0.001]), while comorbidities moderates the relationship between their self-esteem and social adjustment (B = -0.8416, 95% CI, [-1.4529, -0.2302]). The relationship between self-esteem and social adjustment was more pronounced in adolescents without comorbidities than those with comorbidities.

CONCLUSIONS

Psychosocial stress correlates negatively with social adjustment and self-esteem, and indirectly influences social adjustment through self-esteem, while comorbidities (particularly their absence) moderates the relationship between self-esteem and social adjustment.

PRACTICE IMPLICATIONS

Different self-esteem strengthening programs to enhance social adjustment for adolescents with Tourette syndrome may be developed in future studies.

Living with tics: Nursing Care of Pediatric Tourette Syndrome

Tourette syndrome (TS) is a neurodevelopmental movement characterized by abrupt, rapid, repetitive, and non-rhythmic tics. While TS is not life-threatening, such tics and comorbidities affect a children's physical and mental health and social interactions. Treatment is necessary when the children experience physical discomfort, functional dysfunction, and poor interpersonal interaction and mental health. Common management strategies for TS include psychological interventions and pharmacological treatment. Additionally, it is important to consider the individual needs of youths with TS and reassess the treatment outcomes and the need to receive continuous treatment regularly. This review summarizes the symptom management and nursing care measures for youths with TS. Understanding and listening to the healthcare problems of youths with TS can help providers develop healthcare interventions tailored to the youths' needs. Providing the youths with strategies to reduce the tics' interference with their learning outcomes and helping them develop strategies to cope with diverse interpersonal interactions at school are also important. Further, enhancing acceptance given by parents, teachers, and peers, as well as improving the general public's understanding of TS are important measures that promote the youths' social adjustment as well as their ability to coexist with TS.

Pharmacological therapy for Tourette syndrome: What medicine can do and cannot do

Tourette syndrome (TS) is a frequently observed developmental neuropsychological disorder occurring in children. The pathophysiology involves both genetic and environmental factors. In this review, clinical characteristics, pathophysiology, and treatment approaches based on the pathophysiology of TS are presented. The pathophysiology is the acceleration of developmental decrement of dopamine (DA) activity at the terminal of nigro-striatal (NS)-DA system causing DA D2 receptor up-ward regulation. Serotonergic neurons involving in development of the biphasic sleep-wake-rhythm, and locomotion may be involved. Pharmacological treatments constitute an important part in managing TS. Small dose of levodopa and aripiprazole showed the good effect controlling the tics, without side effects. Intervention with enhancing the day time activity and keeping the regular sleep-wake-rhythm, and encouraging locomotion are important. The data from Yoshiko Nomura Neurological Clinic for Children regarding the clinical features and outcomes, medication effects, and OCD and outcomes are shown. To discuss about the environmental factor, how the COVID-19 pandemic affected the TS patients is also presented.

The association between tic medication therapy and psychiatric comorbidities among patients with Tourette syndrome: A national population-based study in Taiwan

BACKGROUND

Tourette syndrome (TS) is often comorbid with attention deficit hyperactivity disorder, obsessive-compulsive disorder, and depression. Medications are the main treatment for TS. Relationships between TS medication therapy and psychiatric comorbidities remain unclear. This study explored the impacts of TS medication on the risk of psychiatric comorbidities using a nationally representative sample of TS in Taiwan.

METHODS

Data from National Health Insurance Research Database in Taiwan was used to identify 997,213 children and adolescents aged 6-18 years who had received a diagnosis of TS based on ICD-9-CM codes in 2000-2010. Cox's proportional hazard regression analysis was conducted to estimate the risk of comorbidities among subjects with and without tic medication therapy.

RESULTS

We found that in TS patients, a lower risk of psychiatric comorbidities occurred in the tic medication therapy group (p = 0.012) and the crude hazard ratio (HR) was 0.6 (95% confidence interval (CI) = 0.4-0.8, p < 0.001). After adjusting for potential confounders of gender, age, income, level of care, department visited, brain injury, and the number of suicide attempts, the risk of comorbidities was still significantly lower in the tic medication therapy group (adjusted HR = 0.5, 95% CI = 0.3-0.6, p < 0.001).

DISCUSSION

One limitation was that we did not include all mediations used to treat psychiatric comorbidities among TS patients. This study found the effectiveness of TS medications on improving psychiatric comorbidities.

CONCLUSIONS

Compared to those without medication, medication therapy appears to have a benefit of decreasing the risk of psychiatric comorbidities. Strategies to improve medication regimens should be considered in clinical settings.

Effectiveness of a modified comprehensive behavioral intervention for tics for children and adolescents with tourette's syndrome: A randomized controlled trial

AIM

To evaluate the effectiveness of a modified four-session Comprehensive Behavioral Intervention for Tics programme for decreasing tics in children and adolescents with Tourette's syndrome.

BACKGROUND

Comprehensive Behavioral Intervention for Tics programme has been shown to decrease tic severity. However, the lack of behaviour therapists in countries, such as in Taiwan, may preclude application of the standard eight-session, 10-week programme.

DESIGN

Randomized controlled study.

METHODS

Participants aged 6-18 years diagnosed with Tourette's syndrome or chronic tic disorder were recruited from February 2015 through September 2016. Participants in the control and intervention groups (N = 23 each) received the routine care (daily pyridoxine [50 mg] and psychoeducation). The intervention group received additional four behavioural intervention sessions over a 3-month period that included psychoeducation, habit reversal training, relaxation training, and education on tic relapse prevention. The outcome measures, Yale Global Tic Severity Scale scores, were assessed at before and after the completion of programme for both groups and again at 3 months follow-up for the intervention group. The effect of the intervention on severity scores was assessed using a generalized estimated equation.

RESULTS

Comparison of scores before and after intervention showed that the intervention significantly decreased the severity of total motor tics (B = -3.28, p < .01) and total tics (B = -5.86, p < .01) as compared with control treatment. YGTSS scores for the intervention group were lower at 3-month follow-up as compared with before treatment or immediately after treatment completion (total tics, p < .001).

CONCLUSION

The modified four-session Comprehensive Behavioral Intervention for Tics programme was more effective than routine care for decreasing tic severity in our cohort of 6- to 18-year olds. This improvement was maintained 3 months after intervention.

IMPACT

Healthcare providers, including nurses, in countries currently not adopting Comprehensive Behavioral Intervention for Tics programme should be made aware of the positive effects of this modified intervention for Tourette's syndrome.

Heterogeneous neurodevelopmental disorders in children with Kawasaki disease: what is new today?

BACKGROUND

Kawasaki disease (KD) is a common vasculitis of childhood in East Asia. The complications of KD ascribed to long-term cardiovascular sequelae are considerably diverse. Although studies have investigated neurodevelopmental problems following KD in the past few decades, they have reported inconsistent conclusions. This study investigated potential epilepsy and associated neurodevelopmental disorders (NDDs) following KD in Taiwanese children.

METHODS

We retrospectively analyzed the data of children aged < 18 years with clinically diagnosed KD from January 1, 2005, to December 31, 2015. These patients were followed up to estimate the prevalence of epilepsy and associated NDDs in comparison with the prevalence in general pediatric population in Taiwan and worldwide.

RESULTS

A total of 612 patients with an average age of 1.6 years were included. The prevalence of associated NDDs was 16.8% (n = 103/612) in the study group, which consisted of epilepsy, intellectual disability (ID), autism spectrum disorders, Tourette syndrome (TS), attention deficit hyperactivity disorder, (ADHD), and others. Moreover, children with KD had a higher prevalence of epilepsy and TS in both Taiwan and worldwide (epilepsy: 2.61% in the KD group vs 0.33% in Taiwan and 0.05-0.8% in worldwide, p < 0.05; TS: 2.77% in the KD group vs 0.56% in Taiwan and 0.3-1% in worldwide, p < 0.05). The prevalence of ID, ADHD, and developmental language disorders was not significantly different between our study patients and those in Taiwan or worldwide.

CONCLUSIONS

Results revealed a higher prevalence rate of NDDs, especially epilepsy and TS, in Taiwanese children with KD than in the general pediatric population in Taiwan. However, these NDDs could be heterogeneous. Children diagnosed with KD were followed up because they had a higher risk of heterogeneous NDDs.

Tourette's syndrome is associated with an increased risk of traumatic brain injury: A nationwide population-based cohort study

INTRODUCTION

Violent motor tics or severe self-harm behaviors have been reported in patients with Tourette's syndrome (TS) and leading to traumatic brain injury (TBI). The study aimed to determine the risk of TBI in TS patients, the effects associated with concurrent psychiatric disorders (attention-deficit/hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), or depressive disorder), and the effects of medication treatment (antipsychotics, antidepressants, or clonidine) on the risk of TBI.

METHODS

Using the National Health Insurance Research Database of Taiwan, 2261 TS patients and 20349 non-TS controls matched by gender and age were enrolled between 2000 and 2012, and followed until the end of 2013. Participants who developed TBI during the follow-up period were identified. Cox regression analysis was performed to examine the risk of TBI between TS patients and non-TS controls.

RESULTS

TS patients were associated with an increased risk of TBI compared to non-TS controls (hazard ratio (HR): 1.59, 95% confidence interval (95% CI): 1.37-1.85). Also, this study revealed TS patients with ADHD, OCD, or depressive disorder predicted a higher TBI incidence rate than those who did not, but the estimate was not statistically significant. Moreover, this study found that TS patients with frequent use of antipsychotics were associated with a lower risk of TBI than infrequent users (HR: 0.76, 95% CI: 0.57-0.99).

CONCLUSIONS

This study highlights the need to pay more attention to the risk of TBI in TS patients, and the importance of adequate antipsychotic medication may reduce the risk of TBI.

Social adjustment experiences of adolescents with Tourette syndrome

AIMS AND OBJECTIVES

To explore and describe the experience of social adjustment of adolescents with Tourette syndrome in Taiwan.

BACKGROUND

Although Tourette syndrome is a non-life-threatening disease, the inherent difficulties in controlling tics and comorbidities can cause long-term physical and psychological issues, as well as social maladjustment among adolescents. Good social adjustment can promote mental health among adolescents. Currently, it is not clear how adolescents with Tourette syndrome can self-adjust and maintain harmonious social interaction with others.

DESIGN

Descriptive phenomenological approach was used in this study. Four criteria were applied to establish the trustworthiness or methodological rigour.

METHODS

Sixteen adolescents with Tourette syndrome were recruited by purposive sampling from a medical centre in Northern Taiwan. Semistructured one-on-one interviews were performed from March 2014-April 2015 for data collection. Every participant was interviewed once or twice, and each interview lasted for duration of around 60-90 min. Data were analysed with Giorgi's phenomenological method for data analysis.

RESULTS

Three themes were identified from the adolescent' interviews. The themes were included visible and invisible destitution, moulding a socially acceptable self and coexisting friends and foes.

CONCLUSIONS

Adolescents with Tourette syndrome experienced that tics are often not understood nor accepted during social interactions with others. However, with age and autonomy of adolescents, they were able to adjust and develop a socially acceptable body image and maintain amicable social interactions with others. Accompanied by positive thinking, support from friends and families, the adolescents could achieve good social adjustments for living with Tourette syndrome.

RELEVANCE TO CLINICAL PRACTICE

The experiences and feelings highlighted in this study can bring awareness to nurses and healthcare professionals for developing interventions that promote healthy social adjustment and mental health for adolescents with Tourette syndrome.

Tourette syndrome and other neurodevelopmental disorders: a comprehensive review

Gilles de la Tourette syndrome (TS) is a complex developmental neuropsychiatric condition in which motor manifestations are often accompanied by comorbid conditions that impact the patient's quality of life. In the DSM-5, TS belongs to the "neurodevelopmental disorders" group, together with other neurodevelopmental conditions, frequently co-occurring. In this study, we searched the PubMed database using a combination of keywords associating TS and all neurodevelopmental diagnoses. From 1009 original reports, we identified 36 studies addressing TS and neurodevelopmental comorbidities. The available evidence suggests the following: (1) neurodevelopmental comorbidities in TS are the rule, rather than the exception; (2) attention deficit/hyperactivity disorder (ADHD) is the most frequent; (3) there is a continuum from a simple (TS + ADHD or/and learning disorder) to a more complex phenotype (TS + autism spectrum disorder). We conclude that a prompt diagnosis and a detailed description of TS comorbidities are necessary not only to understand the aetiological basis of neurodevelopmental disorders but also to address specific rehabilitative and therapeutic approaches.

Neuroimmunology and neuroepigenetics in the establishment of sex differences in the brain

The study of sex differences in the brain is a topic of neuroscientific study that has broad reaching implications for culture, society and biomedical science. Recent research in rodent models has led to dramatic shifts in our views of the mechanisms underlying the sexual differentiation of the brain. These include the surprising discoveries of a role for immune cells and inflammatory mediators in brain masculinization and a role for epigenetic suppression in brain feminization. How and to what degree these findings will translate to human brain development will be questions of central importance in future research in this field.

Gilles de la Tourette syndrome

Gilles de la Tourette syndrome (GTS) is a childhood-onset neurodevelopmental disorder that is characterized by several motor and phonic tics. Tics usually develop before 10 years of age, exhibit a waxing and waning course and typically improve with increasing age. A prevalence of approximately 1% is estimated in children and adolescents. The condition can result in considerable social stigma and poor quality of life, especially when tics are severe (for example, with coprolalia (swearing tics) and self-injurious behaviours) or when GTS is accompanied by attention-deficit/hyperactivity disorder, obsessive-compulsive disorder or another neuropsychiatric disorder. The aetiology is complex and multifactorial. GTS is considered to be polygenic, involving multiple common risk variants combined with rare, inherited or de novo mutations. These as well as non-genetic factors (such as perinatal events and immunological factors) are likely to contribute to the heterogeneity of the clinical phenotype, the structural and functional brain anomalies and the neural circuitry involvement. Management usually includes psychoeducation and reassurance, behavioural methods, pharmacotherapy and, rarely, functional neurosurgery. Future research that integrates clinical and neurobiological data, including neuroimaging and genetics, is expected to reveal the pathogenesis of GTS at the neural circuit level, which may lead to targeted interventions.

Tics and Tourette syndrome in autism spectrum disorders

Autism spectrum disorders (ASDs) are more frequently associated with tic disorders than expected by chance. Variable rates of comorbidity have been reported and common genetic and neurobiological factors are probably involved. The aim of this study was to determine the rate of tic disorders in a clinical sample ( n = 105) of children and adolescents with ASDs and to describe the clinical characteristics of a group with comorbid ASDs and tics ( n = 24). The overlap between tics and other repetitive movements and behaviors in ASDs was carefully assessed. Among individuals with ASDs, 22 percent presented tic disorders: 11 percent with Tourette disorder (TD), and 11 percent with chronic motor tics. All had various degrees of cognitive impairment. An association between the level of mental retardation and tic severity was found. It is concluded that the occurrence of tics in ASDs should not be overlooked and should be carefully evaluated.

VISIT-TS: A multimedia tool for population studies on tic disorders

Population-based assessment of Tourette syndrome (TS) and other tic disorders produces a paradox. On one hand, ideally diagnosis of tic disorders requires expert observation. In fact, diagnostic criteria for TS explicitly require expert assessment of tics for a definite diagnosis. On the other hand, large-scale population surveys with expert assessment of every subject are impracticable. True, several published studies have successfully used expert assessment to find tic prevalence in a representative population (e.g. all students in a school district). However, extending these studies to larger populations is daunting.

We created a multimedia tool to demonstrate tics to a lay audience, discuss their defining and common attributes, and address features that differentiate tics from other movements and vocalizations. A first version was modified to improve clarity and to include a more diverse group in terms of age and ethnicity. The result is a tool intended for epidemiological research. It may also provide additional benefits, such as more representative minority recruitment for other TS studies and increased community awareness of TS.

Provisional Tic Disorder: What to tell parents when their child first starts ticcing

The child with recent onset of tics is a common patient in a pediatrics or child neurology practice. If the child’s first tic was less than a year in the past, the diagnosis is usually Provisional Tic Disorder (PTD). Published reviews by experts reveal substantial consensus on prognosis in this situation: the tics will almost always disappear in a few months, having remained mild while they lasted. Surprisingly, however, the sparse existing data may not support these opinions.

PTD may have just as much importance for science as for clinical care. It provides an opportunity to prospectively observe the spontaneous remission of tics. Such prospective studies may aid identification of genes or biomarkers specifically associated with remission rather than onset of tics. A better understanding of tic remission may also suggest novel treatment strategies for Tourette syndrome, or may lead to secondary prevention of tic disorders.

This review summarizes the limited existing data on the epidemiology, phenomenology, and outcome of PTD, highlights areas in which prospective study is sorely needed, and proposes that tic disorders may completely remit much less often than is generally believed.

Deficits in sensory organization for postural stability in children with Tourette syndrome

Tourette syndrome (TS) is a childhood-onset developmental disorder characterized by involuntary motor and vocal tics. Previous studies have indicated that children with TS demonstrate postural control anomalies when standing. The aim of this study was to compare postural stability under normal and altered sensory conditions in children with TS and healthy control (HC) children. A convenience sample of twelve children with TS (9 boys and 3 girls; 9.4 ± 1.1 yr) and 12 HC age- and gender-matched children (9.2 ± 1.1 yr) participated in this study. The Sensory Organization Test (SOT) was used to assess postural stability under six altered sensory conditions (1. normal vision, fixed support; 2. eyes closed, fixed support; 3. vision sway-referenced, fixed support; 4. normal vision, support sway-referenced; 5. eyes closed, support surface sway-referenced; 6. both vision and support surface sway-referenced) using the SMART Balance Master® 8.2 (NeuroCom® International, Inc, Clackamas, OR, USA). The results showed significant differences between the two groups in conditions 5 and 6 (p=0.003 and 0.002, respectively). The mean composite equilibrium score in children with TS was significantly lower than that of HC children (p<0.000). The results suggested that children with TS had greater difficulty in maintaining postural stability, especially when vestibular information was challenged. The results of this study provide supporting evidence for possible deficits in impaired access to vestibular information and sensorimotor integration of postural control in children with TS.

The effectiveness and safety of plum-blossom needle therapy for Tourette syndrome: study protocol for a randomized controlled trial

Background

Previous studies have indicated that acupuncture can alleviate the symptoms of Tourette syndrome (TS), but the evidence is insufficient. So far, there have been no reports on plum-blossom needle therapy for TS. Here we present a protocol for a randomized controlled trial using plum-blossom needle therapy to treat TS.

Methods/design

Sixty patients will be randomly allocated into either the plum-blossom needle therapy group or the habit reversal training (HRT) group. All patients in each group will be given 12 weeks of treatment, with follow-up at the 24th week. The primary outcome measure will be the mean change from baseline in the total tic score on the Yale Global Tic Severity Scale (YGTSS) at the 12th week. Secondary outcome measures will include the scores on the TS Clinical Global Impression Scale (CGI) and the mean changes from baseline in the YGTSS score and the Children and Adolescents’ Quality of Life Scale (CAQOL) at other time points. Safety will also be evaluated.

Discussion

This trial will evaluate the effectiveness and safety of plum-blossom needle therapy for TS compared with HRT. A limitation of this trial is that patients and acupuncturists cannot be blinded.

Trial registration

ClinicalTrials.gov Identifier: NCT02403258 (Date of registration: March 31, 2015).

A personal 35 year perspective on Gilles de la Tourette syndrome: prevalence, phenomenology, comorbidities, and coexistent psychopathologies

This Series is a personal narrative of my experience with patients with Gilles de la Tourette syndrome and covers its definition and history since the first description in 1825. Controversy entered the prevalence debate early. Although originally considered very rare, in the 1980s, Tourette's syndrome was reported to be common. However, Tourette's syndrome has been shown to occur at a prevalence of about 0·85% to 1%. Tourette's syndrome is more common in the male population, more prominent during childhood, and usually improves, but does not disappear with age. Tourette's syndrome is considered less common in people of sub-Saharan black African, African-American, and American Hispanic ethnic origin. The phenomenology is similar worldwide, indicating a biological basis. The hallmark characteristics are multiple motor and one or more vocal/phonic tics. Other associated features include premonitory urges, a waxing and waning course, and to a much lesser degree, coprolalia. Comorbid disorders are common and are suggested to include obsessive-compulsive disorder and behaviours, attention deficit hyperactivity disorder, and autistic spectrum disorder. Coexistent psychopathologies are suggested to include depression and conduct and personality disorders. Importantly, I argue that Tourette's syndrome is not a unitary condition. Finally, I offer suggestions for future research.

Population prevalence of Tourette syndrome: a systematic review and meta-analysis

The aim of this study was to refine the population prevalence estimate of Tourette Syndrome (TS) in children and to investigate potential sources of heterogeneity in previously published studies. A systematic review was conducted and all qualifying published studies of TS prevalence were examined. Extracted data were subjected to a random-effects meta-analysis weighted by sample size; meta-regressions were performed to examine covariates that have previously been proposed as potential sources of heterogeneity. Twenty-six articles met study inclusion criteria. Studies derived from clinically referred cases had prevalence estimates that were significantly lower than those derived from population-based samples (P = 0.004). Among the 21 population-based prevalence studies, the pooled TS population prevalence estimate was 0.52% (95% confidence interval CI: 0.32-0.85). In univariable meta-regression analysis, study sample size (P = 0.002) and study date (P = 0.03) were significant predictors of TS prevalence. In the final multivariable model including sample size, study date, age, and diagnostic criteria, only sample size (P < 0.001) and diagnostic criteria (omnibus P = 0.003; Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision [DSM-IV-TR]: P = 0.005) were independently associated with variation in TS population prevalence across studies. This study refines the population prevalence estimate of TS in children to be 0.3% to 0.9%. Study sample size, which is likely a proxy for case assessment method, and the use of DSM-IV-TR diagnostic criteria are the major sources of heterogeneity across studies. The true TS population prevalence rate is likely at the higher end of these estimates, given the methodological limitations of most studies. Further studies in large, well-characterized samples will be helpful to determine the burden of disease in the general population.

The prevalence of tic disorders in children and adolescents in Brazil

Tourette syndrome (TS) and tic disorders represent events of familiar magnitude characterized by involuntary movements and/or vocalization. To determine the prevalence of TS/tic disorders we studied a sample of 762 subjects (388 M, 374 F), between 1992 and 1997, age 6 to 43 years old, taken out of a population of 10,155 subjects (4,918 M, 5,237 F; age: 3-56 years old). A structured 4-item questionnaire, direct interview (multistaged), >1 yr follow-up, were used. 9,565 subjects (4,614 M, 4,951 F) sent back the questionnaires, 3,354 of these (1,671 M, 1,683 F) with positive answers to tics. 42 subjects (31 M, 11 F, age: 7-21 years old, mean: 11 years old) met the DSM-III-R criteria. The total minimal prevalence of TS is 0.43%, with a 3:1 ratio male/female. The minimal prevalence of chronic tic disorder is 2.27%. The total minimal prevalence for tic disorders at all is 2.91%. No special education students participation.

The Prevalence of Tic Disorders and Clinical Characteristics in Children

BACKGROUND

Prevalence is a simple statement about the frequency of a disease in the population. For many medical conditions, including Tourette syndrome, there are true cases that have not been previously diagnosed due to problems of access to appropriate clinical services. Therefore, to obtain a trustworthy estimate of prevalence, it is necessary to go beyond cases identified in clinical settings and evaluate community samples.

METHOD

We reviewed 11 community surveys in children with Tourette syndrome (TS) published since 2000. We also examined the frequency of co-occurring psychiatric conditions in community samples and large clinically-ascertained samples.

RESULTS

Transient tics are relatively common affecting as many as 20% of school-age children. The 11 studies reviewed here offer a wide range of estimates from 2.6 to 38 per 1000 children for TS. Six studies provide estimates in a narrower range from 4.3 to 7.6 per 1000, but the confidence interval around this narrower range remains wide. Six studies provided results on chronic tic disorders ranging from 3 to 50 per 1000 for Chronic Motor Tic Disorder and 2.5 to 9.4 per 1000 for Chronic Vocal Tic Disorder. Community samples and large clinically-ascertained samples consistently show high rates of ADHD, disruptive behavior and anxiety disorders in children with TS.

CONCLUSIONS

The wide range of prevalence estimates for TS and chronic tic disorders is likely due to differences in sample size and assessment methods. The best estimate of prevalence for TS in school-age children is likely to fall between 4 and 8 cases per 1000. Clinical assessment of children with chronic tic disorders warrants examination of other problems such as ADHD, disruptive behavior and anxiety.

Health care needs of children with Tourette syndrome

To document the impact of Tourette syndrome on the health care needs of children and access to health care among youth with Tourette syndrome, parent-reported data from the 2007-2008 National Survey of Children's Health were analyzed. Children with Tourette syndrome had more co-occurring mental disorders than children with asthma or children without Tourette syndrome or asthma and had health care needs that were equal to or greater than children with asthma (no Tourette syndrome) or children with neither asthma nor Tourette syndrome. Health care needs were greatest among children with Tourette syndrome and co-occurring mental disorders, and these children were least likely to receive effective care coordination. Addressing co-occurring conditions may improve the health and well-being of children with Tourette syndrome. Strategies such as integration of behavioral health and primary care may be needed to improve care coordination.

Partitioning the heritability of Tourette syndrome and obsessive compulsive disorder reveals differences in genetic architecture

The direct estimation of heritability from genome-wide common variant data as implemented in the program Genome-wide Complex Trait Analysis (GCTA) has provided a means to quantify heritability attributable to all interrogated variants. We have quantified the variance in liability to disease explained by all SNPs for two phenotypically-related neurobehavioral disorders, obsessive-compulsive disorder (OCD) and Tourette Syndrome (TS), using GCTA. Our analysis yielded a heritability point estimate of 0.58 (se = 0.09, p = 5.64e-12) for TS, and 0.37 (se = 0.07, p = 1.5e-07) for OCD. In addition, we conducted multiple genomic partitioning analyses to identify genomic elements that concentrate this heritability. We examined genomic architectures of TS and OCD by chromosome, MAF bin, and functional annotations. In addition, we assessed heritability for early onset and adult onset OCD. Among other notable results, we found that SNPs with a minor allele frequency of less than 5% accounted for 21% of the TS heritability and 0% of the OCD heritability. Additionally, we identified a significant contribution to TS and OCD heritability by variants significantly associated with gene expression in two regions of the brain (parietal cortex and cerebellum) for which we had available expression quantitative trait loci (eQTLs). Finally we analyzed the genetic correlation between TS and OCD, revealing a genetic correlation of 0.41 (se = 0.15, p = 0.002). These results are very close to previous heritability estimates for TS and OCD based on twin and family studies, suggesting that very little, if any, heritability is truly missing (i.e., unassayed) from TS and OCD GWAS studies of common variation. The results also indicate that there is some genetic overlap between these two phenotypically-related neuropsychiatric disorders, but suggest that the two disorders have distinct genetic architectures.

Impact of sex and gonadal steroids on neonatal brain structure

There are numerous reports of sexual dimorphism in brain structure in children and adults, but data on sex differences in infancy are extremely limited. Our primary goal was to identify sex differences in neonatal brain structure. Our secondary goal was to explore whether brain structure was related to androgen exposure or sensitivity. Two hundred and ninety-three neonates (149 males) received high-resolution structural magnetic resonance imaging scans. Sensitivity to androgen was measured using the number of cytosine, adenine, guanine (CAG) triplets in the androgen receptor gene and the ratio of the second to fourth digit, provided a proxy measure of prenatal androgen exposure. There was a significant sex difference in intracranial volume of 5.87%, which was not related to CAG triplets or digit ratios. Tensor-based morphometry identified extensive areas of local sexual dimorphism. Males had larger volumes in medial temporal cortex and rolandic operculum, and females had larger volumes in dorsolateral prefrontal, motor, and visual cortices. Androgen exposure and sensitivity had minor sex-specific effects on local gray matter volume, but did not appear to be the primary determinant of sexual dimorphism at this age. Comparing our study with the existing literature suggests that sex differences in cortical structure vary in a complex and highly dynamic way across the human lifespan.

Tourette syndrome and risk of depression: a population-based cohort study in Taiwan

OBJECTIVE

The temporal relationship between Tourette syndrome (TS) and depression is unclear. This cohort study evaluates the relationship between TS and depression in Taiwan.

METHODS

Claims data from the Taiwan National Health Insurance database were used to conduct retrospective cohort analyses. The study cohort contained 1337 TS patients who were frequency matched by sex, age, urbanization of residence area, parental occupation, and baseline year with 10 individuals without TS. Cox's proportional hazard regression analysis was conducted to estimate the effects of TS on depression risk.

RESULTS

In patients with TS, the risk of developing depression was significantly higher than in patients without TS (p value for log-rank test < .0001). After adjusting for potential confounding, the TS cohort was 4.85 times more likely to develop depression than the control cohort (HR = 4.85, 95% CI = 3.46-6.79).

CONCLUSIONS

In Taiwan, patients with TS have a higher risk of developing depression. The findings of this study are compatible with studies from other countries. This study could provide an evidence to inform the prognosis for a child with TS. The mechanism between TS and increased depression risk requires further investigation.

Cognitive aspects of hyperactivity and overactivity in preadolescents with tourette syndrome

Attention deficit disorder with hyperactivity (ADHD) is a common comorbidity in children with Tourette syndrome (TS). However, motor restlessness and high levels of sensorimotor activation or “overactivity” may be a feature of TS rather than a distinct ADHD comorbidity. The link between overactivity and ADHD in TS has yet to be established and in particular between adult and preadolescent manifestations. The current study furthers this understanding of ADHD features in TS by investigating the relationship between cognitive and behavioral aspects of ADHD and TS. The style of planning (STOP) overactivity scale was compared in preadolescent (n = 17) and adult (n = 17) samples. The STOP overactivity scale measures the characteristic overactive style of planning in everyday life. The aims of the study were twofold as follows: (1) to see if an overactive style was present in adolescents as well as in adults, and (2) to see if this overactive style correlated with hyperactivity, impulsivity, or perfectionism. Results suggest that overactivity may be a better description of the hyperactivity manifestations in TS. Behavioral components of overactivity were present in preadolescents while the cognitive components were more frequent in adults. Overactivity relates at the same time to perfectionism and impulsivity.

Involvement of tryptophan hydroxylase 2 gene polymorphisms in susceptibility to tic disorder in Chinese Han population

Background

Tryptophan hydroxylase-2 (TPH2) is a potential candidate gene for screening tic disorder (TD).

Methods

A case–control study was performed to examine the association between the TPH2 gene and TD. The Sequenom® Mass ARRAY iPLEX GOLD System was used to genotype two single nucleotide polymorphisms (SNPs) of the TPH2 gene in 149 TD children and in 125 normal controls.

Results

For rs4565946, individuals with the TT genotype showed a significantly higher risk of TD than those with TC plus CC genotypes [odds ratio (OR) =3.077, 95% confidence interval (CI): 1.273–7.437; P = 0.009], as did male TD children with the TT genotype (OR = 3.228, 95% CI: 1.153–9.040; P = 0.020). The G allele of rs4570625 was significantly more frequent in TD children with higher levels of tic symptoms (Yale Global Tic Severity Scale, YGTSS) than those in controls among the male children (OR = 1.684, 95%: 1.097–2.583; P = 0.017]. TD children with severe tic symptoms had significantly higher frequencies of rs4546946 TT genotype than did normal controls in boys (OR = 3.292, 95% CI: 1.139–9.513; P = 0.022). We also found that genotype distributions of both SNPs were different between the Asian and European populations.

Conclusions

Our results indicated that the TT genotype of rs4565946 is a potential genetic risk factor for TD, and the allele G of rs4570625 might be associated with the severity of tic symptoms in boys. These polymorphisms might be susceptibility loci for TD in the Chinese Han population. Because of the confounding of co-existing attention deficit hyperactivity disorder (ADHD),these findings need to be confirmed by studies in much larger samples.

Prevalence of tic disorders: a systematic review and meta-analysis

This study evaluated the prevalence of tic disorders. MEDLINE and EMBASE databases were searched, using terms specific to Tourette syndrome and tic disorders, for studies of incidence, prevalence, and epidemiology. Thirty-five studies reporting data from 1985-2011 on the incidence or prevalence of tic disorders in a defined population were included. One reported incidence, and 34 reported prevalence. Meta-analysis of 13 studies of children yielded a prevalence of Tourette syndrome at 0.77% (95% confidence interval, 0.39-1.51%). Prevalence is higher in boys: 1.06% of boys were affected (95% confidence interval, 0.54-2.09%) vs 0.25% of girls (95% confidence interval, 0.05-1.20%). Transient tic disorder comprised the most common tic disorder in children, affecting 2.99% (95% confidence interval, 1.60-5.61%). Meta-analysis of two studies assessing adults for Tourette syndrome revealed a prevalence of 0.05% (95% confidence interval, 0.03-0.08%). The prevalence of tic disorders was higher in all studies performed in special education populations. Tic disorders are more common in children than adults, in boys than girls, and in special education populations. Parents, educators, healthcare professionals, and administrators should be aware of the frequency with which tic disorders occur, and ensure proper access to appropriate care.

Clerodendrum inerme Leaf Extract Alleviates Animal Behaviors, Hyperlocomotion, and Prepulse Inhibition Disruptions, Mimicking Tourette Syndrome and Schizophrenia

Previously, we found a patient with intractable motor tic disorder, a spectrum of Tourette syndrome (TS), responsive to the ground leaf juice of Clerodendrum inerme (CI). Here, we examined the effect of the ethanol extract of CI leaves (CI extract) on animal behaviors mimicking TS, hyperlocomotion, and sensorimotor gating deficit. The latter is also observed in schizophrenic patients and can be reflected by a disruption of prepulse inhibition of acoustic startle response (PPI) in animal models induced by methamphetamine and NMDA channel blockers (ketamine or MK-801), based on hyperdopaminergic and hypoglutamatergic hypotheses, respectively. CI extract (10–300 mg/kg, i.p.) dose-dependently inhibited hyperlocomotion induced by methamphetamine (2 mg/kg, i.p.) and PPI disruptions induced by methamphetamine, ketamine (30 mg/kg, i.p.), and MK-801 (0.3 mg/kg, i.p.) but did not affect spontaneous locomotor activity, rotarod performance, and grip force. These results suggest that CI extract can relieve hyperlocomotion and improve sensorimotor gating deficit, supporting the therapeutic potential of CI for TS and schizophrenia.

Review of prevalence studies of tic disorders: methodological caveats

INTRODUCTION

Tic disorders are neurodevelopmental disorders of childhood associated with psychiatric comorbidity and academic problems. Estimating the prevalence and understanding the epidemiology of tic disorders is more complex than was once thought. Until fairly recently, tic disorders were thought to be rare, but today tics are believed to be the most common movement disorder, with 0.2-46.3% of schoolchildren experiencing tics during their lifetime. Tentative explanations for differing prevalence estimates include the multidimensional nature of tics with a varied and heterogeneous presentation, and the use of different epidemiological methods and study designs.

METHODS

Literature review and analysis of methodological issues pertinent to epidemiological studies of tic disorders.

RESULTS

Epidemiological studies of tic disorders were reviewed, and the main elements of epidemiological studies, including sample selection, case ascertainment strategy, definition of tic disorders, and the degree of coverage of the eligible population (i.e., the response rate) were examined.

DISCUSSION

In order to improve the quality of epidemiological studies of tic disorders, a number of recommendations were made, including but not limited to a review of the diagnostic criteria for tic disorders, and inclusion of new tic disorder categories for those with tics of secondary etiology.

Youths with ADHD with and without tic disorders: comorbid psychopathology, executive function and social adjustment

Attention deficit/hyperactivity disorder (ADHD) and tic disorders (TD) commonly co-occur. Clarifying the psychiatric comorbidities, executive functions and social adjustment difficulties in children and adolescents of ADHD with and without TD is informative to understand the developmental psychopathology and to identify their specific clinical needs. This matched case-control study compared three groups (n=40 each) of youths aged between 8 and 16 years: ADHD with co-occurring TD (ADHD+TD), ADHD without TD (ADHD-TD) and typically developing community controls. Both ADHD groups had more co-occurring oppositional defiant disorder than the control group, and the presence of TD was associated with more anxiety disorders. TD did not impose additional executive function impairments or social adjustment difficulties on ADHD. Interestingly, for youths with ADHD, the presence of TD was associated with less interpersonal difficulties at school, compared to those without TD. The potential various directions of effects from co-occurring TD should be carefully evaluated and investigated for youths with ADHD.

Genetic and Environmental Influences on Stuttering and Tics in Japanese Twin Children

The purpose of this study was to clarify the genetic contribution to stuttering and tics in childhood using the largest databases of Japanese twins. The subjects were 1896 pairs of twin children consisting of 1849 males and 1943 females with a mean age of 11.6 years (3 years to 15 years). All data were gathered by questionnaire. The prevalence of stuttering was 6.7% in males and 3.6% in females (p < .0001). The prevalence of tics was 6.8% in males and 4.1% in females (p = .0021). Concordance rates and polychoric correlations were all higher in monozygotic pairs than in dizygotic pairs irrespective of sex combination. Structural equation modeling showed that the proportion of total phenotypic variance attributable to genetic influences was 80% in males and 85% in females for stuttering, and 28% in males and 29% in females for tics. Moreover, co-occurrence between stuttering and tics was observed in 0.8% of males (tetrachoric correlation: r = .18) and 0.5% of females (r = .31), which was attributed partly (nearly 10% of total genetic variance of each trait) to the common genetic factors, with genetic correlation of r = .32.

Prevalence of Tourette syndrome and chronic tics in the population-based Avon longitudinal study of parents and children cohort

OBJECTIVE

Recent epidemiologic studies have demonstrated that Tourette syndrome (TS) and chronic tic disorder (CT) are more common than previously recognized. However, few population-based studies have examined the prevalence of co-occurring neuropsychiatric conditions such as obsessive-compulsive disorder (OCD) and attention-deficit/hyperactivity disorder (ADHD). We evaluated the prevalence of TS, CT, and their overlap with OCD and ADHD in the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort.

METHOD

A total of 6,768 children were evaluated using longitudinal data from mother-completed questionnaires. DSM-IV-TR diagnoses of TS and CT were derived using three levels of diagnostic stringency (Narrow, Intermediate, and Broad). Validity of the case definitions was assessed by comparing gender ratios and rates of co-occurring OCD and ADHD using heterogeneity analyses.

RESULTS

Age 13 prevalence rates for TS (0.3% for Narrow; 0.7% for Intermediate) and CT (0.5% for Narrow; 1.1% for Intermediate) were consistent with rates from other population-based studies. Rates of co-occurring OCD and ADHD were higher in TS and CT Narrow and Intermediate groups compared with controls but lower than has been previously reported. Only 8.2% of TS Intermediate cases had both OCD and ADHD; 69% of TS Intermediate cases did not have either co-occurring OCD or ADHD.

CONCLUSIONS

This study suggests that co-occurring OCD and ADHD is markedly lower in TS cases derived from population-based samples than has been reported in clinically ascertained TS cases. Further examination of the range of co-occurring neuropsychiatric disorders in population-based TS samples may shed new perspective on the underlying shared pathophysiology of these three neurodevelopmental conditions.

Mutation screening of the HDC gene in Chinese Han patients with Tourette syndrome

Tourette Syndrome (TS) is a complex neuropsychiatric disorder characterized by vocal and motor tics. While environmental causes have been proposed to play a role, genetic factors are believed to be the main determinants of the disorder and its clinical manifestations. Recently, a heterozygous W317X mutation in the histidine decarboxylase gene (HDC) was reported to be responsible for TS in a two-generation pedigree. To investigate whether the HDC gene play a role in TS in Chinese Han population, we performed genetic analysis of the coding region of the HDC gene in 100 Chinese Han patients with TS. Three variants were found including a C > T transition (IVS1 + 52C > T), a novel C > A transition (c.426C > A) in exon 4, and a novel G > A transition (c.1743G > A) in exon 12, both predicted with no amino acid change. Extended analysis was conducted in a total of 120 TS patients and 240 sex, age, and ethnicity matched healthy controls. No significant differences in genotypic and allele distribution between patients and controls for these three variants (P = 0.274, P = 1.000 and P = 0.632 for genotypic distribution, respectively; P = 0.143, P = 1.000 and P = 0.582 for allele distribution, respectively) were observed, suggesting variants in the HDC gene may play little or no role in TS susceptibility in Chinese Han population.

Prevalence and clinical correlates of tic disorders in a community sample of school-age children

To examine the prevalence, clinical characteristics and course of children with tics identified in a community sample. This was a three-stage study. At the age of 9 to 11, parents of 8,244 children born at Aarhus University Hospital Skejby between January 1990 and April 1992 were invited to complete a screening questionnaire about tics. One year later participating parents completed the Strengths and Difficulties Questionnaire (SDQ). From December 2004 to June 2005, when the cohort was 13-15 years of age, parents of the children who screened positive for tics were interviewed in detail about tic disorders. The prevalence of Tourette Syndrome (TS) was 0.6 and 0.6% of chronic motor tics (CMT). Approximately one-third of those with a chronic tic disorder [CTD (TS and CMT)] reported remission of tics by age 13-15. On the parent-rated SDQ children with a CTD were five times more likely (OR = 5.0, 95% CI = 2.6-9.2) to fall into the clinical range of hyperactivity, twice as likely (OR = 2.2, 95% CI = 2.1-7.5) to exhibit disruptive and defiant behavior and over four times more likely to have emotional difficulties (OR = 4.7, 95% CI = 2.5-8.6) compared to children without tic disorders. Children with hyperactivity and CTD were more impaired than subjects with CTD only. Children with CTD and hyperactivity show greater symptom severity across several domains of behavior and overall impairment. In the absence of hyperactivity, children with CTD are at increased risk for emotional difficulties, but not disruptive behavior problems.

Turner syndrome and sexual differentiation of the brain: implications for understanding male-biased neurodevelopmental disorders

Turner syndrome (TS) is one of the most common sex chromosome abnormalities. Affected individuals often show a unique pattern of cognitive strengths and weaknesses and are at increased risk for a number of other neurodevelopmental conditions, many of which are more common in typical males than typical females (e.g., autism and attention-deficit hyperactivity disorder). This phenotype may reflect gonadal steroid deficiency, haploinsufficiency of X chromosome genes, failure to express parentally imprinted genes, and the uncovering of X chromosome mutations. Understanding the contribution of these different mechanisms to outcome has the potential to improve clinical care for individuals with TS and to better our understanding of the differential vulnerability to and expression of neurodevelopmental disorders in males and females. In this paper, we review what is currently known about cognition and brain development in individuals with TS, discuss underlying mechanisms and their relevance to understanding male-biased neurodevelopmental conditions, and suggest directions for future research.

Prevalence of tics in schoolchildren in central Spain: a population-based study

Tic disorders constitute a neurodevelopmental disorder of childhood. This study sought to determine the prevalence of tic disorders in a school-based sample. A randomized sample of 1158 schoolchildren, based on clusters (classrooms) in the province of Burgos (Spain), was identified on a stratified sampling frame combining types of educational center and setting (mainstream schools and special education), using a two-phase approach (screening and diagnosis ascertainment by a neurologist). Tics with/without impairment criterion were diagnosed according to Diagnostic and Statistical Manual of Mental Disorders criteria. In mainstream schools, tics were observed in 125/741 students (16.86%; 95% confidence interval, 14.10-19.63), and were more frequent in boys (87/448, 19.42%; 95% confidence interval, 15.64-23.19) compared with girls (38/293, 12.96%; 95% confidence interval, 8.95-16.98; P = 0.03). In special education centers, tics disorders were observed in 11/54 of children (20.37%; 95% confidence interval, 8.70-32.03). Overall, tics with impairment criteria were less frequent than tics without impairment criteria (4.65% vs 11.85%, P < 0.0001). The most frequent diagnoses involved chronic motor tics (6.07%) and Tourette syndrome (5.26%). Tic disorders are common in childhood, and the use or nonuse of impairment criteria exerts a significant impact on tic prevalence estimates.

Validation of screening instruments for neuroepidemiological surveys of tic disorders

BACKGROUND

The main purpose was to validate a multistage protocol to screen tic disorders in mainstream and special education centers and to investigate whether telephone-based interviews were accurate to diagnose tic disorders when compared with in-person neurological interviews.

METHODS

A school-based survey of children and adolescents (6-16 years). A proxy report questionnaire for tic disorders was completed by teachers, observers, and parents. The diagnosis was confirmed by the neurologist based on the Diagnostic and Statistical Manual of Mental disorders (DSM-IV TR) criteria. The sensitivity, specificity, positive and negative predictive values, the likelihood ratio for a positive result (LR+), and the Kappa coefficients (k) for telephone-based interviews reliability were calculated.

RESULTS

One hundred twenty subjects, 57 from special education center and 63 from a mainstream school were studied. The sensitivity of the proxy report questionnaire was 58% and 36% when completed by the observers (mainstream and special education center, respectively), 40 and 73% when completed by the teachers, and 58 and 36% when completed by the parents. Using any of these 3 screening sources, the sensitivity was 92%, the positive predictive value was 38%, and negative predictive value was 97% (mainstream schools), whereas the sensitivity was 82%, the positive predictive value was 20%, and negative predictive value was 82% (special education centers). Parents (mainstream schools) and teachers (special education center) produced the highest LR+ (7.25 and 1.26, respectively) and the intraobserver reliability of the telephone-based interviews versus in-person neurological interviews gave a k coefficient of 0.83.

CONCLUSIONS

The efficiency of different screening instruments for tic disorders seems to vary in different settings. Telephone-based interviews may be a valid and convenient backup to ascertain the diagnosis of tic disorders when face-to-face neurological examination is not possible.

Tourette syndrome in children: an updated review

Tourette syndrome (TS) is a common neuropsychiatric disorder in children characterized by multiple motor and vocal tics that fluctuate in severity and lasting for at least 1 year. Boys are more commonly affected than girls. Symptoms usually begin with simple motor or vocal tics which then evolve into more complex motor and vocal tics over time. Premonitory sensory urges are common in children over the age of 8 years, and these urges help distinguish tics from symptoms of other movement disorders. Common comorbidities of TS include attention deficit hyperactivity disorder, obsessive-compulsive disorder and learning difficulties. Several genes have been assessed as candidate genes for TS; environmental factors such as stress and streptococcal infections might also contribute to its etiology. The pathophysiology of TS mainly involves dysfunction of basal ganglia-related circuits and hyperactive dopaminergic innervations. A thorough history assessment and neurological examination are important for the correct diagnosis and differentiation from other movement disorders. Treatment for TS should focus on improving the patient's social functioning, minimizing the impairment from cormobid disorders, and controlling tics, if they are severe. Commonly used medications for TS include a2-adrenergic agonists and atypical neuroleptics. Habit reversal therapy is an effective option for TS, and repetitive transcranial magnetic stimulation may be a promising approach for severe cases.