The Prevalence of Tic Disorders and Clinical Characteristics in Children

Diffusion indices alteration in major white matter tracts of children with tic disorder using TRACULA

BACKGROUND

Tic disorder is a neuropsychiatric disorder characterized by involuntary movements or vocalizations. Previous studies utilizing diffusion-weighted imaging to explore white-matter alterations in tic disorders have reported inconsistent results regarding the affected tracts. We aimed to address this gap by employing a novel tractography technique for more detailed analysis.

METHODS

We analyzed MRI data from 23 children with tic disorders and 23 healthy controls using TRActs Constrained by UnderLying Anatomy (TRACULA), an advanced automated probabilistic tractography method. We examined fractional anisotropy (FA), radial diffusivity (RD), axial diffusivity, and mean diffusivity in 42 specific significant white matter tracts.

RESULTS

Our findings revealed notable differences in the children with tic disorders compared to the control group. Specifically, there was a significant reduction in FA in the parietal part and splenium of the corpus callosum and the left corticospinal tract. Increased RD was observed in the temporal and splenium areas of the corpus callosum, the left corticospinal tract, and the left acoustic radiation. A higher mean diffusivity was also noted in the left middle longitudinal fasciculus. A significant correlation emerged between the severity of motor symptoms, measured by the Yale Global Tic Severity Scale, and FA in the parietal part of the corpus callosum, as well as RD in the left acoustic radiation.

CONCLUSION

These results indicate a pattern of reduced interhemispheric connectivity in the corpus callosum, aligning with previous studies and novel findings in the diffusion indices changes in the left corticospinal tract, left acoustic radiation, and left middle longitudinal fasciculus. Tic disorders might involve structural abnormalities in key white matter tracts, offering new insights into their pathogenesis.

Sex differences in the distribution and density of regulatory interneurons in the striatum

Introduction

Dysfunction of the cortico-basal circuitry - including its primary input nucleus, the striatum - contributes to neuropsychiatric disorders, such as autism and Tourette Syndrome (TS). These conditions show marked sex differences, occurring more often in males than in females. Regulatory interneurons, such as cholinergic interneurons (CINs) and parvalbumin-expressing GABAergic fast spiking interneurons (FSIs), are implicated in human neuropsychiatric disorders such as TS, and ablation of these interneurons produces relevant behavioral pathology in male mice, but not in females. Here we investigate sex differences in the density and distribution of striatal interneurons.

Methods

We use stereological quantification of CINs, FSIs, and somatostatin-expressing (SOM) GABAergic interneurons in the dorsal striatum (caudate-putamen) and the ventral striatum (nucleus accumbens) in male and female mice.

Results

Males have a higher density of CINs than females, especially in the dorsal striatum; females have equal distribution between dorsal and ventral striatum. FSIs showed similar distributions, with a greater dorsal-ventral density gradient in males than in females. SOM interneurons were denser in the ventral than in the dorsal striatum, with no sex differences.

Discussion

These sex differences in the density and distribution of FSIs and CINs may contribute to sex differences in basal ganglia function, particularly in the context of psychopathology.

Addressing co-occurring conditions in behavioural therapy for tic disorders: a review and guideline

Co-occurring psychiatric conditions are very common in tic disorders and Tourette syndrome. These additional symptoms are often detrimental to quality of life and may impact upon the implementation and efficacy of evidence-based behavioural therapies (BT) for tics. Combining a review of the available literature, relevant theory, and expert clinical practice, we present a guideline for implementing behavioural and psychosocial interventions when common comorbidities are present. These include attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), anxiety, disruptive behaviour, autism spectrum disorder (ASD) and depression. Practical recommendations are provided for assessment, formulation and management of specific and multiple comorbidities in BT for both children and adults. Despite comorbidities being common in tic disorders, few studies have comprehensively addressed how they may influence the efficacy or implementation of existing therapies or how such treatments may need to be modified or sequenced. We outline recommendations for future research, including randomised control trials of BT for those with specific or multiple comorbidities, as well as adequately powered sub-group analyses within larger scale trials or naturalistic study designs. Transdiagnostic models of psychiatric disorders and treatment, including modular cross-diagnostic therapies, which recognise the dimensionality of psychiatric disorders are also highlighted as an important focus in treatment development in tic disorders.

A review of common influencing factors and possible mechanisms associated with allergic diseases complicating tic disorders in children

Over the past few decades, the incidence of childhood allergic diseases has increased globally, and their impact on the affected child extends beyond the allergy itself. There is evidence of an association between childhood allergic diseases and the development of neurological disorders. Several studies have shown a correlation between allergic diseases and tic disorders (TD), and allergic diseases may be an important risk factor for TD. Possible factors influencing the development of these disorders include neurotransmitter imbalance, maternal anxiety or depression, gut microbial disorders, sleep disturbances, maternal allergic status, exposure to tobacco, and environmental factors. Moreover, gut microbial disturbances, altered immunological profiles, and DNA methylation in patients with allergic diseases may be potential mechanisms contributing to the development of TD. An in-depth investigation of the relationship between allergic diseases and TD in children will be important for preventing and treating TD.

The role of neuroactive steroids in tic disorders

Tics are sudden, repetitive movements or vocalizations. Tic disorders, such as Tourette syndrome (TS), are contributed by the interplay of genetic risk factors and environmental variables, leading to abnormalities in the functioning of the cortico-striatal-thalamo-cortical (CSTC) circuitry. Various neurotransmitter systems, such as gamma-aminobutyric acid (GABA) and dopamine, are implicated in the pathophysiology of these disorders. Building on the evidence that tic disorders are predominant in males and exacerbated by stress, emerging research is focusing on the involvement of neuroactive steroids, including dehydroepiandrosterone sulfate (DHEAS) and allopregnanolone, in the ontogeny of tics and other phenotypes associated with TS. Emerging evidence indicates that DHEAS levels are significantly elevated in the plasma of TS-affected boys, and the clinical onset of this disorder coincides with the period of adrenarche, the developmental stage characterized by a surge in DHEAS synthesis. On the other hand, allopregnanolone has garnered particular attention for its potential to mediate the adverse effects of acute stress on the exacerbation of tic severity and frequency. Notably, both neurosteroids act as key modulators of GABA-A receptors, suggesting a pivotal role of these targets in the pathophysiology of various clinical manifestations of tic disorders. This review explores the potential mechanisms by which these and other neuroactive steroids may influence tic disorders and discusses the emerging therapeutic strategies that target neuroactive steroids for the management of tic disorders.

Sex Differences in Youth with Chronic Tic Disorder and Tourette Syndrome: Evaluation of Tic Severity, Psychological Profiles, and Quality of Life

Background: Tourette syndrome (TS) and Chronic Tic Disorder (CT) are neurodevelopmental conditions involving motor and/or phonic tics. Youth with tics may encounter feelings of isolation, diminished self-esteem and quality of life, and academic difficulties. A growing body of scientific literature suggests sex differences in youth with tics, but findings have been mixed so far. Because symptom severity peaks around puberty, understanding sex differences in tic manifestations and associated symptoms during this critical period is essential. Therefore, we aimed to assess sex differences related to tic symptoms, action planning styles, quality of life, and externalizing/internalizing symptoms in youth with tics. Methods: Our sample consisted of 66 youths with tics (19 girls) aged 7-14 (mean = 10 years). Youths were assessed with clinical interviews, as well as self- and parent-reported inventories evaluating tic symptoms, psychological profiles, and quality of life. Results: While no differences in tic symptoms were found, girls exhibited lower functional inflexibility, reduced overall functional planning effectiveness, and higher impairment in the psychological well-being subscale than boys. Additionally, girls had reduced general life satisfaction and social self-esteem. Boys reported more explosive outbursts, higher levels of hyperactivity, and more difficulties with self-concept. Conclusions: Our analyses suggested differences in several manifestations associated with tics. This introduces new perspectives that refine our understanding of sex differences. A better understanding of sex differences in tic disorders may eventually improve outcomes for all individuals living with these conditions.

Sex differences in the distribution and density of regulatory interneurons in the striatum

Dysfunction of the cortico-basal circuitry - including its primary input nucleus, the striatum - contributes to neuropsychiatric disorders, including autism and Tourette Syndrome (TS). These conditions show marked sex differences, occurring more often in males than in females. Regulatory interneurons, including cholinergic interneurons (CINs) and parvalbumin-expressing GABAergic fast spiking interneurons (FSIs), are implicated in human neuropsychiatric disorders such as TS, and ablation of these interneurons produces relevant behavioral pathology in male mice, but not in females. Here we investigate sex differences in the density and distribution of striatal interneurons, using stereological quantification of CINs, FSIs, and somatostatin-expressing (SOM) GABAergic interneurons in the dorsal striatum (caudate-putamen) and the ventral striatum (nucleus accumbens) in male and female mice. Males have a higher density of CINs than females, especially in the dorsal striatum; females have equal distribution between dorsal and ventral striatum. FSIs showed similar effects, with a greater dorsal-ventral density gradient in males than in females. SOM interneurons were denser in the ventral than in the dorsal striatum, with no sex differences. These sex differences in the density and distribution of FSIs and CINs may contribute to sex differences in basal ganglia function, including in the context of psychopathology.

Treating Tourette Together: An Agenda for Patient-Centered Research Focused on Comprehensive Behavioral Intervention for Tics

To establish a patient-centered agenda for research that will lead to effective, widespread availability, adoption, and utilization of evidence-based behavioral treatment of Tourette syndrome and other tic disorders (TDs), we planned and executed a multistage, collaborative "Treating Tourette Together" research planning project with researchers, clinicians, patients, families, and other interested parties. Priorities for future behavioral treatment research were solicited from these parties via anonymous community surveys, a 2-day research planning summit with 46 individuals representing key stakeholder groups, and community response to summit reports. Four high-priority research domains were identified: (a) expanding treatment access, (b) improving treatment outcomes, (c) optimizing treatment within a broader care model, and (d) evaluating outcomes beyond tic severity. Community-engaged participatory research models can efficiently delineate clear and actionable priorities for clinical research. This approach holds promise for improving the impact of clinical research in TDs and other neuropsychiatric disorders.

Assessment and Treatment of Abnormal Involuntary Movements: A Clinically Focused Narrative Review

LEARNING OBJECTIVES

After participating in this CME activity, the psychiatrist should be better able to:• Categorize and describe different types of abnormal involuntary movements (AIMs).• Identify assessment tools and treatment options for AIMs.

ABSTRACT

Abnormal involuntary movements (AIMs) comprise a diverse group of movement disorders characterized by uncontrolled and unintended movements (e.g., tremors, tics, dystonia). AIMs can occur at any stage of life and pose significant challenges for clinicians. It is difficult to determine their underlying causes due to the complex neurobiological mechanisms involved. Therefore, it is crucial to quantify the severity and progression of AIMs using well-validated measurement scales, such as the Abnormal Involuntary Movement Scale (AIMS). By employing reliable assessment approaches, clinicians can objectively evaluate the motoric manifestations of AIMs and track them over time. Treatment of AIMs varies depending on their nature and etiology. While AIMs often respond to treatment, serious side effects can undermine treatment efficacy. In this clinically focused narrative review, we categorize different types of AIMs and discuss their neurobiological aspects. Further, we emphasize the importance of using well-validated measurement scales for accurate assessment and discuss available treatment modalities that target the specific AIMs manifestations. Additionally, we cover the need for comprehensive care to address the multifaceted nature of AIMs, accounting for their physical manifestations as well as their psychological, social, and functional toll on patients. By embracing a multidisciplinary approach, health care professionals can provide patient-centered care that promotes overall well-being and enhances the lives of patients coping with AIMs. Regular follow-up assessments are necessary to monitor treatment response, adjust medications when needed, and provide ongoing support for individuals affected by AIMs.

Sex Differences in People with Tourette Syndrome and Persistent Motor or Vocal Tic Disorder in the Tourette Association of America International Consortium for Genetics Database

Background and Objective

Tourette Syndrome (TS) and Persistent Motor or Vocal Tic Disorders (PMVT) are more prevalent in males (vs. females). Females with TS may have a delay in diagnosis, and more complex tic features (vs. males). With respect to comorbidities, obsessive-compulsive disorder (OCD) is more prevalent in females; attention-deficit hyperactivity disorder (ADHD) is more prevalent in males. Less is known about sex differences in PMVT. This study analyzes sex differences in outcomes among individuals with TS and PMVT in the Tourette Association of America International Consortium for Genetics dataset (TAAICG).

Design/Methods

Data from 2403 individuals (N=2109 TS; N=294 PMVT) from the TAAICG were analyzed to explore the relationship between sex and TS or PMVT outcomes: age at tic onset; age at diagnosis; time-to-diagnosis; tic severity; and comorbidity rates. Regression models were adjusted for age and family relationships to examine the impact of sex on outcomes.

Results

Females with TS (25.5% of the sample) had a later age of symptom onset (6.5±2.8 vs. 6.0±2.7; p=0.001), later age at diagnosis (13.3±11.2 vs. 10.7±8.1; p=0.0001), and a longer time-to-diagnosis [3 (1,7) vs. 2 (1,5), p=0.01] than males. The total Yale-Global Tic Severity Scale (YGTSS) was lower in females with TS (28.4±9.1 vs. 30.7±8.7); p<0.0001); OCD was slightly more prevalent in females (55% vs. 48.7%; p=0.01) although OCD severity did not differ by sex; ADHD was more prevalent in males (55.7% vs 38.9%; p<0.001). Females with TS had 0.46 lower odds of being diagnosed with TS (p<0.00001). Females with PMVT (42.9% of the sample) had an earlier age of symptom onset (7.9±3.3 vs. 8.9±3.7; p=0.05). Motor or vocal tic severity (YGTSS) was not significantly different. OCD, but not ADHD, was more prevalent in females (OCD: 41.9% vs. 22.2%; p<0.001: ADHD:16.5% vs 21.0%; p=0.4).

Conclusion

Females with TS are less likely to be formally diagnosed and have a later age of symptom onset, later age at diagnosis, longer time-to-diagnosis, higher prevalence of OCD, and lower prevalence of ADHD (vs. males). Females with PMVT have an earlier age of symptom onset, higher prevalence of OCD, but similar ADHD prevalence rates (vs. males). Females with TS and PMVT may be clinically different than males with TS. Future research is needed to understand differences longitudinally in TS and PMVT.

Additive and Interactive Effects of Attention-Deficit/Hyperactivity Disorder and Tic Disorder on Brain Connectivity

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) and persistent tic disorder (PTD) are two neurodevelopmental disorders that frequently co-occur. Contributions of each disorder to cognitive and behavioral deficits have been reported. In this paper, we tested 3 models of pathophysiology for the two disorders (additive, interactive, and phenotypic) using resting-state connectivity associated with each disorder separately and together.

METHODS

Participants were 148 children (55 with ADHD only, 33 with ADHD and PTD, 27 with PTD only, and 33 healthy control subjects) at ages 8 to 12 years. Following diagnostic interviews and behavioral assessment, participants underwent a 128-channel electroencephalography recording. Resting-state, cortical source-level effective connectivity was analyzed across the 4 groups using a 2 × 2 factorial design with factors of ADHD (with/without) and PTD (with/without).

RESULTS

ADHD diagnosis was the primary driver of cognitive and behavioral deficits, while deficits associated with PTD were primarily with thought problems and internalizing problems when compared with controls. Subadditive effects were observed in co-occurring ADHD+PTD for parent-rated behavioral problems and cognitive functions. Aberrant effective connectivity was primarily associated with ADHD, more specifically with lower posterior and occipital-frontal connectivity, while children with PTD exhibited greater left postcentral to precuneus connectivity. Weaker ADHD-related connectivity was associated with more severe behavioral problems, including internalizing behaviors, thought problems, and working memory deficits.

CONCLUSIONS

Similar to general behavioral deficits, aberrant resting-state neural connectivity in pediatric ADHD and PTD combines additively in co-occurring cases. The findings of this study support ADHD as a focus of treatment in comorbid cases, given the driving role of ADHD in both behavioral and neurophysiological deficits.

Direct additive genetics and maternal effect contribute to the risk of Tourette disorder

BACKGROUND

Risk for Tourette disorder, and chronic motor or vocal tic disorders (referenced here inclusively as CTD), arise from a combination of genetic and environmental factors. While multiple studies have demonstrated the importance of direct additive genetic variation for CTD risk, little is known about the role of cross-generational transmission of genetic risk, such as maternal effect, which is not transmitted via the inherited parental genomes. Here, we partition sources of variation on CTD risk into direct additive genetic effect (narrow-sense heritability) and maternal effect.

METHODS

The study population consists of 2 522 677 individuals from the Swedish Medical Birth Register, who were born in Sweden between 1 January 1973 and 31 December 2000, and followed for a diagnosis of CTD through 31 December, 2013. We used generalised linear mixed models to partition the liability of CTD into: direct additive genetic effect, genetic maternal effect and environmental maternal effect.

RESULTS

We identified 6227 (0.2%) individuals in the birth cohort with a CTD diagnosis. A study of half-siblings showed that maternal half-siblings had twice higher risk of developing a CTD compared with paternal ones. We estimated 60.7% direct additive genetic effect (95% credible interval, 58.5% to 62.4%), 4.8% genetic maternal effect (95% credible interval, 4.4% to 5.1%) and 0.5% environmental maternal effect (95% credible interval, 0.2% to 7%).

CONCLUSIONS

Our results demonstrate genetic maternal effect contributes to the risk of CTD. Failure to account for maternal effect results in an incomplete understanding of the genetic risk architecture of CTD, as the risk for CTD is impacted by maternal effect which is above and beyond the risk from transmitted genetic effect.

Patients' experience of accessing support for tics from primary care in the UK: an online mixed-methods survey

BACKGROUND

Tics are common in children and young people and may persist into adulthood. Tics can cause challenges with social, occupational, physical, and academic functioning. The current study explores the perceptions of adults with tics and parents/carers of young people with tics regarding their experience of accessing support from professionals in primary care in the UK.

METHODS

Two online cross-sectional surveys were completed by 33 adults with tics and 94 parents/carers of children with tics. Participants were recruited across three online tic support groups. Tic specialist psychologists, academic researchers, and people with lived experience of tics provided feedback on the surveys before they were made available online. Mixed-method analyses were conducted on the surveys. Qualitative data from the free-text responses were analysed using thematic analysis and triangulated with quantitative findings where appropriate.

RESULTS

While some participants felt supported by general practitioners (GPs), many felt dismissed. The impact of tics was not always explored, nor information on tics provided, during the consultation. Although 78.7% of participants were referred to secondary care for their tics, some struggled to get the referral. Within secondary care, most adult respondents were assessed by neurologists whilst young people were typically assessed by paediatricians or psychiatrists. Most of these secondary care clinicians did not specialise in tic disorders, with only 27.9% of participants being assessed by tic specialists. Mode waitlist time was 3-6 months for young people and longer for adult respondents. Some participants were referred to multiple secondary care services, spanning neurology, paediatrics, and psychiatry, with each stating that they do not provide support for tics. 21% of participants mentioned being discharged from secondary care with no ongoing support. Almost one-third of respondents accessed support within private healthcare.

CONCLUSIONS

Generally, more negative than positive experiences were reported. Possible contributing factors included a lack of clear tic referral pathways, long waitlists, a lack of information about tics provided in primary care appointments and a lack of support offered following diagnosis by secondary care services, together with poor access to tic specialist clinicians. This study highlights areas where improvements to UK services for tics can be made.

Improvement of Tourette syndrome symptoms after intractable temporal lobe epileptic surgery: a case report

BACKGROUND

The comorbidities of either epilepsy or Tourette syndrome (TS) are heterogeneous. However, the co-occurrence of epilepsy and TS conditions is rarely encountered, let alone effective treatments that address both neurologic disorders at the same time.

METHODS

We report a 24-year-old female patient who was diagnosed with TLE and TS. She presented for seizure control. After evaluation with stereo-electroencephalography and electrocorticography monitoring, the patient underwent a resective surgery treatment and was followed for 9 months.

RESULTS

At the last follow-up, the patient remained seizure free and unexpectedly showed great improvement in TS symptoms and its psychiatric comorbidities.

CONCLUSION

This anecdotal case highlights the close association between TLE and TS and we suggest that epilepsy and TS share some common pathophysiologic mechanisms.

Power of combined modern technology: Multitouch-multiuser tabletops and virtual reality platforms (PowerVR) in social communication skills training for children with neurological disorders: A pilot study

New technologies such as multitouch-multiuser tabletops (MMT) and virtual reality (VR) provide modern neurorehabilitation options. The aim was to describe the structure of acquired social communication deficits in children with neurological disorders (ND) and implement a new PowerVR method- combined MMT/VR interfaces, into social neurorehabilitation. The study was designed based on the Structured Social Rehabilitation Model. Sixty children with ND aged 8-13 years participated: 28 with epilepsy, 10 with traumatic brain injury (TBI), 3 with tic disorders, 3 with stroke, 16 with other ND. A total of 16 patients (M = 10.5 years, SD = 1.8) completed trainings with pre- and post-intervention assessments. Forty-four patients participated in base-level assessment (M = 10.2 years, SD = 1.6). Two age-matched patients practiced in pairs on MMT and individually in VR. The most impaired components in patients were theory of mind (ToM) skills. A total of 64% of children presented behavioral problems related to executive dysfunctions. Patients lacked conflict resolution (median 38% out of 100%) and empathy skills (25%). After trainings, communication and cooperation, pragmatics, social attention, conflict resolution, and empathy skills improved. Patients' general verbal ToM and understanding false beliefs (p < .005) increased. Children's ability to start conversations improved; they experienced less bullying. Findings suggest that the combined technology-based intervention PowerVR offers increased power for multicomponent training of socio-emotional skills.

Teacher Knowledge of Tourette Syndrome and Associated Factors

BACKGROUND

TS is associated with learning disabilities and educational impairment. Teacher knowledge about TS may have a positive impact on students with TS, but factors associated with teacher knowledge of TS are not known.

METHODS

In this cross-sectional study, teachers of youth with TS and of a community control group completed a Teacher Understanding of Tourette Syndrome Survey (TUTS), a pilot questionnaire enquiring about self-perceived understanding, teacher knowledge, and sources of information. We compared TUTS scores between TS and control groups and between those who did and did not use specific sources of information about TS using Wilcoxon rank-sum tests. Bivariate correlation analyses were used to evaluate associations between teacher knowledge and potential contributing factors.

RESULTS

Data from 114 teachers of children with TS and 78 teachers of control subjects were included. Teachers of youth with TS had significantly more knowledge, had higher self-perceived understanding, and used more sources of information than teachers of the control group. Teachers who knew of the Tourette Association of America and who gathered information themselves had higher knowledge about TS than those who did not.

CONCLUSION

Teachers of children with TS know more about TS and use more sources to learn about TS than teachers of children without TS.

Behavioral Interventions for Children and Adults with Tic Disorder

Over the past decade, behavioral interventions have become increasingly recognized and recommended as effective first-line therapies for treating individuals with tic disorders. In this article, we describe a basic theoretical and conceptual framework through which the reader can understand the application of these interventions for treating tics. The three primary behavioral interventions for tics with the strongest empirical support (habit reversal, Comprehensive Behavioral Intervention for Tics, and exposure and response prevention) are described. Research on the efficacy and effectiveness of these treatments is summarized along with a discussion of the research evaluating the delivery of these treatments in different formats and modalities. The article closes with a review of the possible mechanisms of change underlying behavioral interventions for tics and areas for future research.

Brief youth self-report screener for tics: Can a subscale of the Motor tic, Obsession and compulsion, and Vocal tic Evaluation Survey (MOVES) identify tic disorders in youth?

Tics are unwanted, repetitive movements and sounds that frequently present during childhood. They are typically brief and purposeless, but can create significant distress for individuals, and often co-occur with other neuropsychiatric conditions. Thus, early identification of tics is warranted. Unfortunately, tics are often misdiagnosed, and because tics may wax and wane, identification can be difficult, especially in the context of routine clinical visits. There are limited tools that can be used to reliably identify tics in clinical practice, especially in non-specialty settings. The purpose of the current study was to evaluate the performance of the Motor tic, Obsession and compulsion, and Vocal tic Evaluation Survey (MOVES), a self-report scale with some support as a screening tool. In addition, the performance of a subset of questions (the MOVES-6) was evaluated for rapid screening. Participants were recruited across two study sites and included children and adolescents diagnosed with Tourette syndrome (n = 151) or another persistent tic disorder (n = 10) and community controls (n = 74). Results suggest both the MOVES and the MOVES-6 have high sensitivity (90% and 88%, respectively) and at least acceptable specificity (77% and 86%, respectively) compared with expert assessment of tic disorders, suggesting that both versions can identify tic disorders without high proportions of false negatives. Both versions were highly sensitive with acceptable specificity regardless of sex, race/ethnicity, and age. The MOVES and MOVES-6 show promise as a screener for tics or tic disorders, but additional research is needed, particularly in a general population setting.

Modified Comprehensive Behavioral Intervention for Tics: Treating Children With Tic Disorders, Co-Occurring ADHD, and Psychosocial Impairment

Our objective was to evaluate the feasibility and acceptability, and preliminary efficacy of a modified comprehensive behavioral intervention for tics (MCBIT) therapy for youth with chronic tic disorders (CTDs), co-occurring attention-deficit hyperactivity disorder (ADHD), and associated psychosocial impairment. Seventeen youth ages 10-17 with CTD and co-occurring ADHD were randomly assigned to the MCBIT group (n = 9) or to a control group where they received traditional comprehensive behavioral intervention for tics (CBIT) therapy (n = 8). Both groups received ten 55-minute weekly treatment sessions, and two 55-minute biweekly relapse prevention sessions. Sixteen of the 17 participants completed the study, and acceptability ratings in both treatment groups were high with no significant differences in expectation of improvement. The MCBIT and CBIT groups in combination showed significant improvement in tic severity, ADHD symptom severity, and tic-related impairment. Group differences were not significant. The results indicate that MCBIT treatment is feasible and acceptable for youth with CTD and ADHD, and is similarly well tolerated relative to traditional CBIT. Results were not sufficiently superior to recommend MCBIT over CBIT for this population. However, given the demonstrated benefit of behavioral treatments that target co-occurring conditions concurrently, continuing to examine novel behavioral approaches that can target tics and related conditions simultaneously and successfully is recommended.

Proof of Concept Study of an Oral Orthotic in Reducing Tic Severity in Tourette Syndrome

The use of an oral orthotic, called an occlusal splint, has gained recognition for the potential to reduce the frequency of tics for individuals with Persistent Tic Disorders. The purpose of this study was to assess the feasibility of a fully blinded, randomized controlled trial (RCT) to assess the safety, tolerability and initial efficacy of the oral orthotic in youth with chronic tics. Thirteen youth were randomly assigned to wear an active or sham orthotic in a two week double-blind RCT, with a 4-6 week unblinded follow up period. A statistically significant difference was found for change in tic severity between participants wearing the active and sham orthotic. However, this difference was not replicated during the follow up period. The oral orthotic is a promising intervention for the reduction of tics in youth with Tourette's Syndrome and is worthy of continued study to establish intervention efficacy and mechanism of action.

Lifetime Prevalence, Predictors and Comorbidities of Tic Disorders: A Population-Based Survey of Children and Adolescents in Iran

In this population-based survey, we have evaluated the lifetime prevalence of tic disorders and related sociodemographic factors and comorbidities of them. The data obtained from face-to-face interviews with 29,885 children and adolescents aged 6-18 years. We used the multistage cluster sampling method and a cross-sectional design. Tic disorders and other psychiatric disorders were assessed using the Persian version of the Kiddie Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version (K-SADS-PL). The lifetime prevalence of tic disorders was 1.5% (95% CI  (1.3-1.7%)). The highest prevalence was in the age range of 15-18 years old with 1.9% (95% CI  (1.6-2.3%)).57.7% (95% CI 51.8-63.3%) of patients with tic disorders had comorbidity with other psychiatric disorders. Increasing the prevalence of tic disorder with increasing age among Iranian children and adolescents, emphasizes the need to pay more attention to use of pharmacological and non-pharmacological treatments and increase education to families in this regard.

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.

Mitochondrial DNA variants spectrum and the association with chronic Tic disorders

BACKGROUND

Tic disorders (TD) are childhood-onset neuropsychiatric disorders characterized by single or multiple sudden, rapid, recurrent, and motor tics and/or vocal tics. Several nuclear genes that involved in mitochondrial functions suggest potential role of mitochondria in tic deficit.

METHODS

To evaluate the association of mitochondrial DNA (mtDNA) variants with Tic disorders, we screened the whole mitochondrial genomes in 493 TD patients and 109 age- and sex matched healthy controls using next-generation sequencing technology.

RESULTS

A total of 1918 mtDNA variants including 1220 variants in patients only, 154 variants in controls only, and 544 variants shared by both cases and controls were identified. We found higher number of overall mtDNA variants in TD patients (P =0.00028). The variant density in MT-ATP6/8 and MT-CYB coding regions had significant difference between TD patients and controls (P=0.0025 and P=0.003, respectively). Furthermore, we observed a significant association of 15 common variants with TD based on additive model, including m.14766C>T, m.14783T>C, m.14905G>A, and m.15301G>A in MT-CYB; m.4769A>G, m.10398A>G, m.12705C>T, and m.12850A>G in MT-ND genes; m.7028C>T in MT-CO1; m.8701A>G in MT-ATP6; two noncoding variants with m.16223C>T, m.5580T>C; and three rRNA variants with m.1438A>G and m.750A>G in RNR1, and m.2352T>C in RNR2.

CONCLUSIONS

Our data provide the evidence of mtDNA variants associated with tic disorders. The accumulation of the heteroplasmic levels may increase the risk of TD. Replication studies with larger samples are necessary to understand the pathogenesis of TD.

Profiles of Proinflammatory Cytokines and T Cells in Patients With Tourette Syndrome: A Meta-Analysis

Background

Tic disorder is a neurodevelopmental disorder characterized by motor and phonic tic symptoms. Tourette syndrome (TS) is a subtype of tic disorder that shows more persistent tic symptoms. The etiological mechanism of TS concerning immune dysfunction remains unclear due to limited evidence, especially for pediatric TS patients.

Method

In the present study, a meta-analysis was performed to confirm the identified changes in proinflammatory cytokines and T cells of pediatric TS patients. A total of five databases, including PubMed, Web of Science, PsycINFO, Google Scholar and the China National Knowledge Infrastructure (CNKI), were used for the literature search. The standardized mean difference (SMD) and mean difference (MD) with a 95% confidence interval (CI) were used to present the effect size of each type of proinflammatory cytokine and T cell. Sensitivity analysis, subgroup analysis and meta-regression analysis were used to explore the heterogeneity of the meta-analysis. This meta-analysis was registered in the International Platform of Registered Systematic Review and Meta-analysis Protocols (number: INPLASY2021110079).

Results

In the 25 studies included in this meta-analysis, thirteen studies focused on the levels of T cells, and twelve studies focused on the levels of proinflammatory cytokines. Based on the random-effects model, the pooled MDs are -1.45 (95% CI: -3.44, 0.54) for CD3 cells, -4.44 (95% CI: -6.80, -2.08) for CD4 cells, and 1.94 (95% CI: -0.08, 3.97) for CD8 cells. The pooled SMDs are1.36 for IL-6 (95% CI: 0.00, 2.72) and 2.39 for tumor necrosis factor alpha (TNF-α) (95% CI: 0.93, 3.84).

Conclusion

We provided evidence of immune dysfunction in pediatric TS patients, with elevated levels of particular proinflammatory cytokines and disproportionate changes in T-cell subpopulations. Small to large effect sizes were identified for increased IL-6 levels as well as a reduced number of T helper cells, while a large effect size was identified for increased TNF-α levels. These results indicate a close association between peripheral immune activation and TS. However, the most direct and meaningful interaction between peripheral immune status and microglial activation in the central nervous system in TS patients requires further exploration.

The Prevalence and Comorbidity of Tic Disorders and Obsessive-Compulsive Disorder in Chinese School Students Aged 6-16: A National Survey

Background: Obsessive-compulsive disorder (OCD) and tic disorders (TDs) are closely related and considered to etiologically overlap. Both disorders are characterized by repetitive behaviors. TD and OCD often co-occur. The high comorbidity between OCD and TD individuals suggests that we also need to pay more attention to the homogeneity and heterogeneity between TS and OCD. To date, there has been no systematic nationwide epidemiological survey of the mental health (including tic disorders and obsessive-compulsive disorder) of children and adolescents in China. Methods: A two-stage epidemiological study of psychiatric point prevalence was conducted. We used the multistage cluster stratified random sampling strategy to assess five provinces of China. The Child Behavior Checklist was used to identify behavioral problems among the enrolled students in the first stage. The results from the Mini-International Neuropsychiatric Interview for Children and Adolescents and evaluations from two psychiatrists based on the Diagnostic and Statistical Manual-IV were used to make a diagnosis. Point weighted prevalence for TD and OCD was estimated. We adjusted prevalence estimates with the product of sampling weights and poststratification weights. Standard error values and 95% confidential intervals were generated with Taylor series linearization. Rao−Scott adjusted chi-square (χ2) tests were employed to compare the prevalence estimates of different age and sex groups. Results: In the first stage, 73,992 participants aged 6−16 years old were selected. The prevalence rates of OCD and TDs were 1.37% (95% CI: 1.28−1.45) and 2.46% (95% CI: 2.35−2.57), respectively. The prevalence of OCD was found to be higher in girls (p < 0.001) and higher in boys with transient tic disorder (TTD) (p < 0.001) and Tourette’s syndrome (TS) (p < 0.001). The most common comorbidity of TS was OCD (40.73%), and for OCD, it was TS (11.36%). Conclusions: Our study is the first nationwide survey on the prevalence of TD (2.46%) and OCD (1.37%) in school students aged 6−16 years old in China. The high comorbidity between OCD and TD individuals suggested overlap based on the prevalence dimensions, which might be influenced by age and sex. This result suggested that we also need to pay more attention to the homogeneity and heterogeneity between TS and OCD.

Stimulant Induced Movement Disorders in Attention Deficit Hyperactivity Disorder

Stimulants, such as amphetamine and methylphenidate, are one of the most effective treatment modalities for attention deficit hyperactivity disorder (ADHD) and may cause various movement disorders. This review discusses various movement disorders related to stimulant use in the treatment of ADHD. We reviewed the current knowledge on various movement disorders that may be related to the therapeutic use of stimulants in patients with ADHD. Recent findings suggest that the use of stimulants and the onset/aggravation of tics are more likely to be coincidental. In rare cases, stimulants may cause stereotypies, chorea, and dyskinesia, in addition to tics. Some epidemiological studies have suggested that stimulants used for the treatment of ADHD may cause Parkinson’s disease (PD) after adulthood. However, there is still a lack of evidence that the use of stimulants in patients with ADHD may cause PD, and related studies are only in the early stages. As stimulants are one of the most commonly used medications in children and adolescents, close observations and studies are necessary to assess the effects of stimulants on various movement disorders, including tic disorders and Parkinson’s disease.

A prospective clinical cohort-based study of the prevalence of OCD, obsessive compulsive and related disorders, and tics in families of patients with OCD

BACKGROUND

The lifetime prevalence of obsessive - compulsive disorder (OCD) is currently estimated at 2 - 3% and the prevalence in first-degree family members is estimated to range between 10 and 11%. Separating OCD from other anxiety disorders and including it into the new "obsessive - compulsive and related disorders" (OCRDs) category has had a dramatic impact on the diagnosis, while also contributing to the better understanding of the genetics of these disorders. Indeed, grouping OCD with body dysmorphic disorder (BDD), and body-focused repetitive behaviors such as trichotillomania (hair pulling), onychophagia (nail biting), and excoriation (skin picking) into the same diagnostic family has resulted in a much greater lifetime prevalence (> 9%). These diagnostic changes necessitate an updated epidemiological study, thus motivating this investigation.

METHODS

The study sample comprised of 457 patient's cases from an Israeli and an Australian OCD center. Interviews were completed as a part of the intake or during treatment in each of the centers. Prevalence of OCD, OCRDs, tics, and other psychiatric comorbidities in first- and second-degree relatives was assessed by interviewing the OCD patients. Interviews were conducted by at least two researchers (LC, OBA, JZ) and only family information on which the interviewers have reached consensus was considered.

RESULTS

Initial analyses revealed an increase of OCD and OCRD prevalence in first- and second-degree family members as compared to the current literature due to reclassification of these disorders in DSM-5.

CONCLUSION

The new category of OCRD has changed the landscape of epidemiological studies in OCD. Further and broader studies are needed in order to better understand the lifetime prevalence of OCRD in first- and second-degrees family member.

Cognitive control processes in behavior therapy for youth with Tourette's disorder

BACKGROUND

Cognitive control processes are implicated in the behavioral treatment of Tourette's disorder (TD). However, the influence of these processes on treatment outcomes has received minimal attention. This study examined whether cognitive control processes and/or tic suppression predicted reductions in tic severity and treatment response to behavior therapy.

METHOD

Fifty-three youth with TD or a pervasive tic disorder participated in a randomized wait list-controlled trial of behavior therapy. Following a baseline assessment to evaluate psychiatric diagnoses, tic severity, and cognitive control processes (e.g., response selection, inhibition, and suppression), youth were randomly assigned to receive eight sessions of behavior therapy (n = 23) or a wait list of equal duration (n = 28). Youth receiving immediate treatment completed a post-treatment assessment to determine improvement in tic severity. Meanwhile, youth in the wait list condition completed another assessment to re-evaluate tic severity and cognitive control processes, and subsequently received 8 sessions of behavior therapy followed by a post-treatment assessment to determine improvement.

RESULTS

A multiple linear regression model found that pretreatment inhibition/switching on the Delis-Kaplan Executive Function System Color-Word Interference Test predicted reductions in tic severity after behavior therapy (β = -.36, t = -2.35, p = .025, ƞ2  = .15). However, other cognitive control processes and tic suppression did not predict treatment response and/or reductions in tic severity. Small nonsignificant effects were observed in cognitive control processes after behavior therapy.

CONCLUSION

Cognitive control processes may influence tic severity reductions in behavior therapy. Notably, even when other cognitive control processes are impaired and youth are initially unable to voluntarily suppress their tics, youth with TD can still benefit from behavior therapy. Findings offer implications for clinical practice and research for TD.

Meta-Analysis: Efficacy and Tolerability of Vesicular Monoamine Transporter Type 2 Inhibitors in the Treatment of Tic Disorders

Vesicular monoamine transporter type 2 (VMAT2) inhibitors may be an effective therapy for chronic tic disorders (CTD), including Tourette syndrome (TS), but there has not been a meta-analysis compiling available evidence from randomized controlled trials (RCTs). We performed a systematic review and meta-analysis to evaluate the efficacy, acceptability, and tolerability of VMAT2 inhibitors for CTD/TS. PubMed, CENTRAL, and Embase were searched for double-blinded RCTs of VMAT2 inhibitors versus placebo for the treatment of CTD/TS. Change in tic severity measured by the Yale Global Tic Severity Scale (efficacy) and rates of discontinuation attributed to adverse effects (tolerability) or all causes (acceptability) were extracted closest to 12 weeks. Mean difference (MD) and odds ratio (OR) were the effect size indexes for efficacy and acceptability/tolerability, respectively. Data were pooled through random-effects meta-analysis weighted by inverse variance. Five RCTs involving eight comparisons were included. Meta-analysis found a nonsignificant effect on efficacy (k = 8; N = 583; MD = -0.71; 95% confidence interval [CI], -1.93 to 0.50; P = 0.24), and there was certainty that the true effect is nonclinically meaningful (high quality of evidence). Meta-analysis found decreased tolerability (k = 7; N = 626; OR = 2.67; 95% CI, 1.21-5.92; P = 0.01) and decreased acceptability (k = 8; N = 626; OR = 1.90; 95% CI, 1.14-3.18; P = 0.01), although those comparisons were limited because of the relatively small number of events across trials. Meta-analyses did not support the efficacy of VMAT2 inhibitors in the short-term treatment of tic disorders and suggested no clinically meaningful effect of these agents on tic symptoms. © 2022 International Parkinson and Movement Disorder Society.

Sex differences in patients with Tourette syndrome

BACKGROUND

Tourette syndrome (TS) is a neurodevelopmental disorder characterized by the presence of motor and phonic tics. It is at least three times more common in males compared with females; however, the clinical phenomenology between sexes has not been fully examined. We aimed to contrast the clinical features between males and females with TS and chronic tic disorder.

METHODS

We studied 201 consecutive patients fulfilling the diagnostic criteria for TS, persistent (or chronic) motor and vocal tic disorder and provisional tic disorder that were considered within the TS spectrum disorder. We performed blinded evaluations of video-recordings and retrospectively reviewed the clinical charts of all patients.

RESULTS

Age ranges between 4 and 65 years. Males represented 77.6% of patients in the cohort. Overall, no differences were observed in the frequency, distribution and complexity of tics between sexes, except for a higher frequency of attention-deficit/hyperactivity disorder (ADHD) (P = .003) among males. Patients younger than 18-years old, in addition to a higher frequency of ADHD (P = .026), males had a statistically higher frequency of complex motor tics (P = .049) and earlier age at onset (P = .072) than females in the multivariate regression analysis. However, these differences were lost in patients older than 18 years, due to increased complexity of tics in females with aging.

CONCLUSIONS

A sexual dimorphism was observed between patients with TS mainly before age of 18 years, suggesting an earlier onset of some types of tics and ADHD in males compared to females.

Digital and remote behavioral therapies for treating tic disorders: Recent advances and next steps

The rapid expansion of access to and engagement with digital technology over the past 15 years has transformed the potential for remote delivery of evidence-based digital health interventions (DHIs). Digital and remote behavioral interventions have the potential to address current gaps in the provision of evidence-based therapies in healthcare services. As the lack of access to behavioral treatments for people with tic disorders is a pressing issue across the world, there is great potential for DHIs to close this treatment gap. Here, we present a critical synthesis of the recent key advances in the field of digitally delivered, remote therapy for tics, outlining the research evidence for the clinical and cost-effectiveness and acceptability of digital or remotely delivered therapy. We found five trials aimed at reducing tic severity in children and young people and one trial for adults. The evidence supports the clinical utility of DHIs to deliver tic therapies, which shows promise in being clinically efficacious compared to an active control. Furthermore, DHIs in trials show good adherence and engagement and are acceptable to patients. The role of human support (including therapists and parents for young people) is likely to be important to encourage adherence. DHIs, where the main therapeutic content is delivered via web-based chapters, are likely to reduce clinical time, and maintain intervention fidelity, but further research is required to understand cost-effectiveness. Despite utilizing randomized controlled trials, only two trials were sufficiently powered to address efficacy and only one trial explored contextual factors that may influence engagement. Moreover, only one trial followed patients for >12 months, thus further long-term follow-ups are required. Specifically, we note that despite an emerging evidence base, DHIs for tics are yet to be routinely implemented in healthcare provision in any country. Drawing on the existing evidence, we conclude by proposing a stepped care model, in which digital therapy is implemented as a widely accessible first-line treatment using a purely online or therapist-supported approach.

Urge intolerance predicts tic severity and impairment among adults with Tourette syndrome and chronic tic disorders

BACKGROUND

Individuals with Tourette Syndrome and Persistent Tic Disorders (collectively TS) often experience premonitory urges-aversive physical sensations that precede tics and are temporarily relieved by tic expression. The relationship between tics and premonitory urges plays a key role in the neurobehavioral treatment model of TS, which underlies first-line treatments such as the Comprehensive Behavioral Intervention for Tics (CBIT). Despite the efficacy of CBIT and related behavioral therapies, less than 40% of adults with TS respond to these treatments. Further examination of the relationship between premonitory urges, tic severity, and tic impairment can provide new insights into therapeutic targets to optimize behavioral treatment outcomes. This study examined whether urge intolerance-difficulty tolerating premonitory urges-predicted tic severity and tic-related impairment among adults with TS.

METHODS

Participants were 80 adults with TS. Assessments characterized premonitory urge, distress tolerance, tic severity, and tic impairment. We used structural equation modeling (SEM) to examine the construct of urge intolerance-comprised of premonitory urge ratings and distress tolerance ratings. We first evaluated a measurement model of urge intolerance through bifactor modeling, including tests of the incremental value of subfactors that reflect premonitory urge severity and distress tolerance within the model. We then evaluated a structural model where we predicted clinician-rated tic severity and tic impairment by the latent variable of urge intolerance established in our measurement model.

RESULTS

Analyses supported a bifactor measurement model of urge intolerance among adults with TS. Consistent with theoretical models, higher levels of urge intolerance predicted greater levels of clinician-rated tic severity and tic impairment.

CONCLUSION

This investigation supports the construct of urge intolerance among adults with TS and distinguishes it from subcomponents of urge severity and distress tolerance. Given its predictive relationship with tic severity and tic impairment, urge intolerance represents a promising treatment target to improve therapeutic outcomes in adults with TS.

European clinical guidelines for Tourette syndrome and other tic disorders-version 2.0. Part II: psychological interventions

Part II of the European clinical guidelines for Tourette syndrome and other tic disorders (ECAP journal, 2011) provides updated information and recommendations for psychological interventions for individuals with tic disorders, created by a working group of the European Society for the Study of Tourette Syndrome (ESSTS). A systematic literature search was conducted to obtain original studies of psychological interventions for tic disorders, published since the initial European clinical guidelines were issued. Relevant studies were identified using computerized searches of the MEDLINE and PsycINFO databases for the years 2011-2019 and a manual search for the years 2019-2021. Based on clinical consensus, psychoeducation is recommended as an initial intervention regardless of symptom severity. According to a systematic literature search, most evidence was found for Habit Reversal Training (HRT), primarily the expanded package Comprehensive Behavioral Intervention for Tics (CBIT). Evidence was also found for Exposure and Response Prevention (ERP), but to a lesser degree of certainty than HRT/CBIT due to fewer studies. Currently, cognitive interventions and third-wave interventions are not recommended as stand-alone treatments for tic disorders. Several novel treatment delivery formats are currently being evaluated, of which videoconference delivery of HRT/CBIT has the most evidence to date. To summarize, when psychoeducation alone is insufficient, both HRT/CBIT and ERP are recommended as first-line interventions for tic disorders. As part of the development of the clinical guidelines, a survey is reported from ESSTS members and other tic disorder experts on preference, use and availability of psychological interventions for tic disorders.

The effectiveness of Chinese herbal medicine for tic disorders in children and adolescents: A protocol for systematic review and meta analysis

BACKGROUND

The tic disorders are common neuropsychiatric disorders that affects the growth and development of children and adolescents. Chinese herbal medicine is commonly used for the treatment of tic disorders. However, there is no consensus on the difference in clinical efficacy compared with routine treatment. Therefore, we plan to perform a systematic review and meta-analysis to review the clinical efficacy of Chinese herbal medicine for tic disorders.

METHODS

Cochrane Central Register of Controlled Trials, PubMed, EMBASE, Chinese National Knowledge Infrastructure, Chinese Bio-medical Database, and Wanfang database will be searched from their inception until March 31, 2021. The meta-analysis will be conducted with Review Manager 5.3 software to systematically review the clinical efficacy and safety of Chinese herbal medicine for tic disorders. The primary outcome will include the improvement rate (amount) of tic symptoms using related scales or methods, and the secondary outcome will include adverse events.

RESULTS

This analysis will provide useful information about clinical efficacy and safety of Chinese herbal medicine for tic disorders.

CONCLUSIONS

Our study will generate strong evidence of Chinese herbal medicine for patients with tic disorders and provide suggestions for clinical practice.

Acute and Long-Term Effects of an Internet-Based, Self-Help Comprehensive Behavioral Intervention for Children and Teens with Tic Disorders with Comorbid Attention Deficit Hyperactivity Disorder, or Obsessive Compulsive Disorder: A Reanalysis of Data from a Randomized Controlled Trial

Attention deficit hyperactivity disorder (ADHD), obsessive compulsive disorder (OCD) and tic disorders (TD) commonly co-occur. In addition, specific inattention difficulties and poor impulse control are related to TD in the absence of comorbid ADHD. In this study we reanalyzed data from a recently completed study comparing internet-delivered, self-help comprehensive behavioral intervention for tics (ICBIT) with a waiting-list control group. The current study describes the effects of an (ICBIT) in children and adolescents with TD with and without comorbid diagnoses of ADHD or OCD at post intervention and over three- and six-month follow-up periods. Thirty-eight 7 to 18-year-olds completed the ICBIT. Of these, 16 were diagnosed with comorbid ADHD and 11 were diagnosed with OCD. A significant improvement in tic measures was found in all groups. Both the TD + ADHD and the TD − ADHD groups were similar in the magnitude of tic reduction from baseline to post-treatment, and at the three and six-month follow-up assessments. However, the TD + OCD group benefitted less from intervention than the TD—OCD group. There were meaningful reductions in parental reports of inattention, as well as hyperactive and impulsive symptoms at post intervention and over the 6-month follow-up period. Thus, ICBIT can be effectively delivered in the presence of comorbid ADHD or OCD symptomatology and may reduce symptoms of inattention and impulsivity. Larger studies of ICBIT in children and teens with TD and comorbid ADHD and OCD are needed to optimize responses to ICBIT.

Tic Detection in Tourette Syndrome Patients Based on Unsupervised Visual Feature Learning

A clinical diagnosis of tic disorder involves several complex processes, among which observation and evaluation of patient behavior usually require considerable time and effective cooperation between the doctor and the patient. The existing assessment scale has been simplified into qualitative and quantitative assessments of movements and sound twitches over a certain period, but it must still be completed manually. Therefore, we attempt to find an automatic method for detecting tic movement to assist in diagnosis and evaluation. Based on real clinical data, we propose a deep learning architecture that combines both unsupervised and supervised learning methods and learns features from videos for tic motion detection. The model is trained using leave-one-subject-out cross-validation for both binary and multiclass classification tasks. For these tasks, the model reaches average recognition precisions of 86.33% and 86.26% and recalls of 77.07% and 78.78%, respectively. The visualization of features learned from the unsupervised stage indicates the distinguishability of the two types of tics and the nontic. Further evaluation results suggest its potential clinical application for auxiliary diagnoses and evaluations of treatment effects.

Homework adherence predicts therapeutic improvement from behavior therapy in Tourette's disorder

Behavior therapy is a first-line intervention for Tourette's Disorder (TD), and a key component is the practice of therapeutic skills between treatment visits (i.e., homework). This study examined the relationship between homework adherence during behavior therapy for TD and therapeutic outcomes, and explored baseline predictors of homework adherence during treatment. Participants included 119 individuals with TD (70 youth, 49 adults) who received behavior therapy in a clinical trial. After a baseline assessment of tic severity and clinical characteristics, participants received 8 sessions of behavior therapy. Therapists recorded homework adherence at each therapy session. After treatment, tic severity was re-assessed by independent evaluators masked to treatment condition. Greater overall homework adherence predicted tic severity reductions and treatment response across participants. Early homework adherence predicted therapeutic improvement in youth, whereas late adherence predicted improvement in adults. Baseline predictors of greater homework adherence in youth included lower hyperactivity/impulsivity and caregiver strain. Meanwhile in adults, baseline predictors of increased homework adherence included younger age, lower hyperactivity/impulsivity, obsessive-compulsive severity, anger, and greater work-related disability. Homework adherence is an integral component of behavior therapy and linked to therapeutic improvement. Strategies that improve homework adherence may optimize the efficacy of behavioral treatments and improve treatment outcomes.

Feasibility and acceptability of an online mindfulness-based group intervention for adults with tic disorders

BACKGROUND

Preliminary research suggests that a mindfulness-based treatment approach may be beneficial for adults with tic disorders. In the present study, we report on the feasibility, acceptability, safety, and symptomatic effect of a novel online mindfulness-based group intervention for adults with Tourette syndrome or persistent tic disorder. Data from this study will directly inform the conduct of a funded randomized controlled trial comparing the efficacy of this intervention to another active psychological intervention.

METHODS

One cohort of adults with Tourette syndrome participated in an 8-week online mindfulness-based group intervention. Measures of feasibility, acceptability, and safety were administered throughout and at posttreatment. Self-reported measures of mindfulness and clinician-rated measures of tic severity and impairment were administered at baseline and posttreatment.

RESULTS

Data on refusal, dropout rate, attendance, participant satisfaction, and safety suggest that this is a feasible and acceptable intervention. However, participant adherence to home practice was lower than anticipated. Mindfulness, tic severity, and tic-related impairment only modestly improved from baseline to posttreatment. Qualitative analysis of participant feedback revealed aspects of the intervention that were most helpful and also areas for improvement.

CONCLUSIONS

Data suggest that although this is a feasible and acceptable intervention, it should be modified to enhance participant adherence, more successfully engage the target mechanism, and optimize outcomes.

TRIAL REGISTRATION

Clinicaltrials.gov registration # NCT03525626 . Registered on 24 April 2018.

Clinical features and neuropsychiatric comorbidities in pediatric patients with tic disorders: a retrospective chart review study from South Korea

BACKGROUND

Tic disorders are childhood-onset neuropsychiatric disorders characterized by multiple motor or vocal tics with frequent comorbidities and a broad spectrum of phenotypic presentations. In this study, we aimed to investigate the clinical characteristics and comorbid neuropsychiatric conditions in pediatric patients with tic disorders.

METHODS

We retrospectively reviewed the medical records of 119 pediatric patients (89 males, 30 females) who were diagnosed with tic disorders according to the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) at Uijeongbu St. Mary's Hospital, Republic of Korea, between January 2012 and July 2019.

RESULTS

The mean age of tic onset was 6.9 years (range, 1-14) and the mean age at diagnosis was 8 years (range, 1-17). The mean lag between tic onset and diagnosis was 13.3 months (range, 0.25-132). The most common, first-presenting tics were eye blinking (50.4%), followed by jaw or lip movement (29.4%) and throat clearing (29.4%). Thirty-seven (31.1%) patients had at least one co-occurring neuropsychiatric disorder at the time of tic diagnosis. Subtypes of tic disorders, types of initial tics, and presence of neuropsychiatric comorbidities were not associated with tic severity. Tic severity was associated with greater functional impairment and tic noticeability (p < 0.05). A relatively shorter time to diagnosis was associated with tic severity (Spearman's ρ = - 0.14, p = 0.11).

CONCLUSIONS

The evolving nature of tic expression and severity, high prevalence of neuropsychiatric comorbidities, and associated functional impairments emphasize the importance of comprehensive assessment during the disease course for determining and prioritizing goals of treatment.

Defining tic severity and tic impairment in Tourette Disorder

OBJECTIVE

Treatment guidelines for Tourette's Disorder (TD) are based on patients' degree of tic severity and impairment. However, clear benchmarks for determining tic severity and impairment have not been established. This study examined benchmarks of tic severity and tic impairment using the Yale Global Tic Severity Scale (YGTSS) and the Clinical Global Impression of Severity (CGI-S).

METHOD

Individuals with TD or another Tic Disorder (N = 519) recruited across nine sites were administered a diagnostic interview, the YGTSS, and the CGI-S. Correlations and trend analyses contrasted YGTSS scores across CGI-S ratings. A logistic regression model examined predictive benchmarks for tic severity, tic impairment, and global severity. Model classifications were compared against CGI-S ratings, and agreement was examined using kappa.

RESULTS

Spearman correlations between the CGI-S and YGTSS scores ranged from 0.54 to 0.63 (p < 0.001). Greater CGI-S ratings were associated with a linear stepwise increase in YGTSS Total Tic scores, Impairment scores, and Global Severity scores. Despite moderate-to-strong associations (ρ = 0.45-0.56, p < 0.001) between the CGI-S and predictive logistical regression models, only fair agreement was achieved when applying classification benchmarks (κ = 0.21-0.32, p < 0.001).

CONCLUSIONS

CGI-S ratings are useful to characterize benchmarks for tic severity, tic impairment, and global severity on the YGTSS. Logistic regression model benchmarks had only fair agreement with the CGI-S and underscore the heterogeneity of TD symptoms. Collectively, findings offer guidance on the delineation of tic severity categorizations to apply evidence-based treatment recommendations.

General health and mortality in Tourette syndrome and chronic tic disorder: A mini-review

Current knowledge on the general somatic health and causes of death in Tourette syndrome and chronic tic disorder is very limited. Here, we review the available literature on the topic, while highlighting strengths and weaknesses of the studies conducted to date. These previous works have suggested associations between Tourette syndrome and chronic tic disorder and a range of health conditions, including autoimmune disorders, common allergies and respiratory diseases, sleep difficulties, and metabolic and cardiovascular outcomes. Additionally, the risk of mortality in tic disorders might be higher than that of the general population, but specific causes of death have rarely been studied, except for substance use-related deaths and suicide, which are significantly higher in individuals with Tourette syndrome and chronic tic disorder. Many of these emerging findings require replication and extension but, taken together, they suggest that that it might be sensible to monitor the general health and suicide risk of individuals with Tourette syndrome or chronic tic disorder across the lifespan. We suggest further avenues for research on this topic.

Cohort profile: Epidemiology and Genetics of Obsessive-compulsive disorder and chronic tic disorders in Sweden (EGOS)

PURPOSE

The EGOS study (Epidemiology and Genetics of Obsessive-compulsive disorder and chronic tic disorders in Sweden) is a large-scale, epidemiological, prospective cohort that is used to identify genetic and environmental risk factors in the etiology of obsessive-compulsive disorder (OCD) and chronic tic disorders (CTD).

METHODS

Individuals born between January 1954 and December 1998 with at least two diagnoses of OCD or CTD at different timepoints in the National Patient Register (NPR), and followed between January 1997 and December 2012, represent the EGOS source population (n = 20,374). The Swedish Multi-Generation Registry (MGR) are then used to define family relatedness for all cases and additional phenotypic and demographic data added to the resultant database. To create an epidemiologically valid subset of the source cohort that also includes biospecimens and additional phenotyping, we contact cases from within the source population. To date, 6832 invitations have been sent out and 1853 (27%) have elected to participate in the EGOS biospecimen collection.

RESULTS

To date, 1608 biological samples have been collected, of which 1249 are genotyped and 832 supplementary Obsessive-Compulsive Inventory-Revised (OCI-R) and/or Florida Obsessive-Compulsive Inventory (FOCI) have been completed by individuals with OCD and/or CTD, age 16-64 years. DNA samples are genotyped using Infinium Global Screening Array and will undergo whole-exome sequencing in the future. Detailed information is available for each individual through linkage to the Swedish national registers, e.g., identification of additional psychiatric diagnoses, medical diagnoses, birth-related variables, and relevant demographic and social data.

CONCLUSION

EGOS benefits from a genetically homogeneous sample with epidemiological ascertainment, minimizing the risk of confounding due to population stratification on ascertainment bias. In addition, this study is built upon clinical diagnoses of OCD and CTD in specialized psychiatric care, which reduces further biases and case misclassification.

Rage attacks in Tourette Syndrome and Chronic Tic Disorder: a systematic review

Tourette syndrome (TS) and chronic motor/vocal tic disorder (CTD) are neurodevelopmental conditions defined by the occurrence of multiple tics. Besides the well-known association with attention deficit/hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD), rage attacks (RA) represent common and detrimental symptoms for patients. Inorder to explore prevalence of RA in tic disorders, relation to tic severity/comorbidities and available treatments, we performed a systematic literature review based on PRISMA Guidelines. 32 studies published between January 2008 - December 2019 were deemed suitable for the analysis and provided a prevalence of 20-67 %. Most findings showed a direct correlation with tic severity and a significant impact on psychosocial functioning. Although apparently related to comorbid ADHD, RA also frequently occur as independent manifestations. Association with other comorbidities, such as OCD, impulse control and mood disorders has also been reported, not yet fully established. Behavioral interventions appear to be effective, whereas there is limited evidence concerning the efficacy of medication. In TS/CTD, RA may be regarded as a major comorbidity that requires clinical investigation in order to develop personalized treatments.

Impaired automatic but intact volitional inhibition in primary tic disorders

The defining character of tics is that they can be transiently suppressed by volitional effort of will, and at a behavioural level this has led to the concept that tics result from a failure of inhibition. However, this logic conflates the mechanism responsible for the production of tics with that used in suppressing them. Volitional inhibition of motor output could be increased to prevent the tic from reaching the threshold for expression, although this has been extensively investigated with conflicting results. Alternatively, automatic inhibition could prevent the initial excitation of the striatal tic focus-a hypothesis we have previously introduced. To reconcile these competing hypotheses, we examined different types of motor inhibition in a group of 19 patients with primary tic disorders and 15 healthy volunteers. We probed proactive and reactive inhibition using the conditional stop-signal task, and applied transcranial magnetic stimulation to the motor cortex, to assess movement preparation and execution. We assessed automatic motor inhibition with the masked priming task. We found that volitional movement preparation, execution and inhibition (proactive and reactive) were not impaired in tic disorders. We speculate that these mechanisms are recruited during volitional tic suppression, and that they prevent expression of the tic by inhibiting the nascent excitation released by the tic generator. In contrast, automatic inhibition was abnormal/impaired in patients with tic disorders. In the masked priming task, positive and negative compatibility effects were found for healthy controls, whereas patients with tics exhibited strong positive compatibility effects, but no negative compatibility effect indicative of impaired automatic inhibition. Patients also made more errors on the masked priming task than healthy control subjects and the types of errors were consistent with impaired automatic inhibition. Errors associated with impaired automatic inhibition were positively correlated with tic severity. We conclude that voluntary movement preparation/generation and volitional inhibition are normal in tic disorders, whereas automatic inhibition is impaired-a deficit that correlated with tic severity and thus may constitute a potential mechanism by which tics are generated.

Development and Open Trial of a Psychosocial Intervention for Young Children With Chronic Tics: The CBIT-JR Study

The Comprehensive Behavioral Intervention for Tic Disorders (CBIT) has demonstrated efficacy in large randomized controlled trials for children (≥9 yrs), adolescents and adults with Tourette Syndrome and Chronic Tic Disorders. Given the early age of onset for tic disorders, a large portion of affected individuals with chronic tic disorders are less than 9 years of age and appropriate developmental adaptations of behavioral treatment have not yet been tested. The goal of this study was to adapt and evaluate the acceptability and utility of a family-based adaptation of CBIT for children under 9 years of age. Children 5-8 years of age (N = 15) with chronic tics were recruited from three study sites. CBIT was adapted for use with young children and included habit reversal strategies introduced in a developmentally appropriate game format and function-based interventions to reduce family accommodation of and attention to tic symptoms. Children and parents described high level of treatment satisfaction and study retention rate was 100%. Treatment response rate was 54% (CGI-I = 1 or 2) with a significant decrease in the YGTSS total score (Cohen's d = 0.73) that was largely maintained at 3-month and 1-year follow-up assessments. Treatment was associated with reduction of some symptoms of tic-related comorbid syndromes and with changes in parental accommodation and attention to tics. Future research should determine if parental attention to tics and symptom accommodation are important mediators of treatment outcome, or if participating in this intervention at a younger age may prevent the chronic course of tic symptoms.

Assessment and Management of Tic Disorders in Pediatric Primary Care Settings

Purpose of Review

Pediatricians and other primary care providers are often the first and sole healthcare clinicians of patients who present with tics. However, limited primary care pediatric training in neuropsychiatric concerns, as well as perceived lack of comfort and preparation, make it challenging for these clinicians to confidently identify and manage tic disorders.

Recent Findings

Current empirical findings of tic disorder management relevant to pediatric physicians, including assessment, psychoeducation, behavioral interventions, psychotropic medications, and alternative treatments are reviewed.

Summary

This article discusses neuropsychiatric and medical complexities of tic disorder assessment, with particular emphasis on differential and comorbid diagnoses. Tiered referral recommendations, based on symptom severity, impairment, and consideration of comorbid conditions, are provided. Future directions for tic management, including dissemination of evidence-based treatments of tic disorders and multidisciplinary teams within pediatric primary care settings, are included.

Disentangling Restrictive and Repetitive Behaviors and Social Impairments in Children and Adolescents with Gilles de la Tourette Syndrome and Autism Spectrum Disorder

Gilles de la Tourette syndrome (GTS) and autism spectrum disorder (ASD) are two neurodevelopmental disorders with male predominance, frequently comorbid, that share clinical and behavioral features. The incidence of ASD in patients affected by GTS was reported to be between 2.9% and 22.8%. We hypothesized that higher ASD rates among children affected by GTS previously reported may be due to difficulty in discriminating GTS sub-phenotypes from ASD, and the higher scores in the restrictive and repetitive behaviors in particular may represent at least a “false comorbidity”. We studied a large population of 720 children and adolescents affected by GTS (n = 400) and ASD (n = 320), recruited from a single center. Patients were all assessed with The Yale Global Tic Severity Rating Scale (YGTSS), The Autism Diagnostic Observation Schedule (ADOS), The Autism Diagnostic Interview Revised (ADI-R), The Children’s Yale–Brown Obsessive–Compulsive Scale (CY-BOCS), and The Children’s Yale–Brown Obsessive–Compulsive Scale for autism spectrum disorder (CY-BOCS ASD). Our results showed statistically significant differences in ADOS scores for social aspects between GTS with comorbid attention deficit hyperactivity disorder (ADHD) and obsessive–compulsive disorder (OCD) sub-phenotypes and ASD. No differences were present when we compared GTS with comorbid ASD sub-phenotype to ASD, while repetitive and restrictive behavior scores in ASD did not present statistical differences in the comparison with GTS and comorbid OCD and ASD sub-phenotypes. We also showed that CY-BOCS ASD could be a useful instrument to correctly identify OCD from ASD symptoms.

Heterogeneity and Polygenicity in Psychiatric Disorders: A Genome-Wide Perspective

Genome-wide association studies (GWAS) have been performed for many psychiatric disorders and revealed a complex polygenic architecture linking mental and physical health phenotypes. Psychiatric diagnoses are often heterogeneous, and several layers of trait heterogeneity may contribute to detection of genetic risks per disorder or across multiple disorders. In this review, we discuss these heterogeneities and their consequences on the discovery of risk loci using large-scale genetic data. We primarily highlight the ways in which sex and diagnostic complexity contribute to risk locus discovery in schizophrenia, bipolar disorder, attention deficit hyperactivity disorder, autism spectrum disorder, posttraumatic stress disorder, major depressive disorder, obsessive-compulsive disorder, Tourette’s syndrome and chronic tic disorder, anxiety disorders, suicidality, feeding and eating disorders, and substance use disorders. Genetic data also have facilitated discovery of clinically relevant subphenotypes also described here. Collectively, GWAS of psychiatric disorders revealed that the understanding of heterogeneity, polygenicity, and pleiotropy is critical to translate genetic findings into treatment strategies.