Tourette syndrome, co-morbidities and quality of life

Circulating retinol and 25(OH)D contents and their association with symptoms in children with chronic tic disorders

The present study measured serum levels of vitamin A (VA) and vitamin D (VD) in children with chronic tic disorders (CTD) and investigated their potential association with CTD and comorbidity of attention deficit hyperactivity disorder (ADHD) and the association of their co-insufficiencies or deficiencies with CTD symptoms. A total of 176 children (131 boys and 45 girls, median age of 9 years) with CTD were recruited as the CTD group. During the same period, 154 healthy children were selected as the healthy control (HC) cohort. Circulating retinol and 25-hydroxyvitamin D (25[OH]D) levels were measured for all participants using high-performance liquid chromatography (HPLC) and tandem mass spectrometry. The Yale Global Tic Severity Scale (YGTSS) was employed for the assessment of tic status and CTD impairment. The Swanson, Nolan, and Pelham Rating Scale (SNAP-IV) and the Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) were used to evaluate comorbidity symptoms. CTD pediatric participants exhibited markedly diminished circulating retinol and 25(OH)D levels compared to HCs. Moreover, VA and VD deficiencies and their co-insufficiencies/deficiencies were more prevalent in CTD participants than HCs. Circulating 25(OH)D levels were inversely proportional to the YGTSS motor tic scores. YGTSS scores in CTD children with only VA or VD insufficiency or deficiency or with VA and VD co-insufficiency/deficiency did not differ from those in CTD children with normal VA and VD. CTD children with comorbid ADHD displayed reduced circulating retinol and 25(OH)D concentrations and elevated prevalence of VD deficiency compared to CTD participants without comorbid ADHD. Lower serum retinol content was intricately linked to the presence of elevated CTD and comorbid ADHD. VA and VD deficiencies and their co-insufficiencies/deficiencies were markedly enhanced in CTD pediatric participants compared to HCs. Lower VA concentration was linked to the presence of enhanced CTD and comorbid ADHD. Therefore, children with CTD, especially with comorbid ADHD, may be at a higher risk of VA or VD deficiency, which may prompt the clinicians to consider whether blood tests for VA and VD in CTD children would be helpful for clinical care.

Predictors of Health-Related Quality of Life in Neurodivergent Children: A Systematic Review

Health-related Quality of Life (HRQoL) is a multi-faceted construct influenced by a myriad of environmental, demographic, and individual characteristics. Our understanding of these influencers remains highly limited in neurodevelopmental conditions. Existing research in this area is sparse, highly siloed by diagnosis labels, and focused on symptoms. This review synthesized the evidence in this area using a multi-dimensional model of HRQoL and trans-diagnostically across neurodevelopmental conditions. The systematic review, conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Checklist, was completed in June 2023 using Medline, PsycInfo, Embase, PubMed, and Cochrane Library. Our search revealed 78 studies that examined predictors of HRQoL in neurodevelopmental conditions. The majority of these studies focused on autism and ADHD with a paucity of literature in other conditions. Cross-diagnosis investigations were limited despite the fact that many of the examined predictors transcend diagnostic boundaries. Significant gaps were revealed in domains of biology/physiology, functioning, health perceptions, and environmental factors. Very preliminary evidence suggested potentially shared predictors of HRQoL across conditions including positive associations between HRQoL and adaptive functioning, male sex/gender, positive self-perception, physical activity, resources, and positive family context, and negative associations with diagnostic features and mental health symptoms. Studies of transdiagnostic predictors across neurodevelopmental conditions are critically needed to enable care models that address shared needs of neurodivergent individuals beyond diagnostic boundaries. Further understanding of HRQoL from the perspective of neurodivergent communities is a critical area of future work.

Use of Medical Cannabis in Patients with Gilles de la Tourette's Syndrome in a Real-World Setting

Objective: Tourette's syndrome (TS) is a neurodevelopmental disorder characterized by vocal and motor tics and other comorbidities. Clinical recommendations for the use of medical cannabis are established, yet further guidance is needed. The aim of this study was to describe the experience of patients with TS with medical cannabis. Materials and Methods: TS patients were recruited from a registry of patients ("Tikun Olam" company). Questionnaires were answered before and after 6 months of treatment. Patients were divided into two groups: (A) patients who responded and (B) patients who did not respond to the follow-up questionnaire. In group A, an analysis was made to evaluate the presence and frequency of motor and vocal tics. The patients' general mood, employment status, quality of life, and comorbidities were also included in the analysis. Results: Seventy patients were identified. The tetrahydrocannabinol and cannabidiol mean daily dose was 123 and 50.5 mg, respectively. In group A, a statistically significant improvement was identified in quality of life (p<0.005), employment status (p=0.027), and in the reduction of the number of medications (p<0.005). Sixty-seven percent and 89% of patients with obsessive-compulsive disorder and anxiety comorbidities, respectively, reported an improvement. No statistically significant improvement was identified in motor tics (p=0.375), vocal tics (p>0.999), tics frequency (p=0.062), or general mood (p=0.129). The most frequent adverse effects were dizziness (n=4) and increased appetite (n=3). Conclusion: Subjective reports from TS patients suggest that medical cannabis may improve their quality of life and comorbidities. More studies are needed to evaluate the efficacy and safety of medical cannabis. Registry in the MOH: https://www.moh.gov.sg/ (Trial number: 0185-19-ASF).

Premonitory Urge and Tic Severity, Comorbidities, and Quality of Life in Chronic Tic Disorders

BACKGROUND

Tics are intimately associated with premonitory urges (PU) but knowledge about urges is still limited, with small sample sizes often limiting the generalizability of findings.

OBJECTIVES

This study addressed the following open questions: (1) is tic severity associated with urge severity, (2) how common is relief, (3) which comorbidities are associated with urges, (4) are urges, tics, and comorbidities associated with lower quality of life, and (5) can complex and simple, motor and vocal tics be differentiated based on PU?

METHODS

N = 291 patients who reported a confirmed diagnosis of chronic primary tic disorder (age = 18-65, 24% female) filled out an online survey assessing demographic data, comorbid conditions, location, quality and intensity of PU, as well as quality of life. Every tic was recorded, and whether the patient experienced a PU, the frequency, intensity, and quality of that urge.

RESULTS

PU and tic severity were significantly associated, and 85% of urge-related tics were followed by relief. A diagnosis of attention deficit/hyperactivity disorder (ADHD) or depression, female gender, and older age increased the likelihood of experiencing PU, while more obsessive compulsive (OCD) symptoms and younger age were associated with higher urge intensities. PU, complex vocal tics, ADHD, OCD, anxiety, and depression were related to lower quality of life. Motor and vocal, complex and simple tics did not differ regarding PU intensity, frequency, and quality, or relief.

CONCLUSIONS

The results shed light on the relationship between PU, tics, comorbidities, age, gender, and quality of life in tic disorders.

Validation of the Diagnostic Interview Schedule for Children (DISC-5) Tic Disorder and Attention-Deficit/Hyperactivity Disorder Modules

Effective methods to assess mental disorders in children are necessary for accurate prevalence estimates and to monitor prevalence over time. This study assessed updates of the tic disorder and attention-deficit/hyperactivity disorder (ADHD) modules of the Diagnostic Interview Schedule for Children, Version 5 (DISC-5) that reflect changes in diagnostic criteria in the Diagnostic and Statistical Manual of Mental Disorders (Fifth edition, DSM-5). The DISC-5 tic disorder and ADHD parent- and child-report modules were compared to expert clinical assessment for 100 children aged 6-17 years (40 with tic disorder alone, 17 with tic disorder and ADHD, 9 with ADHD alone, and 34 with neither) for validation. For the tic disorder module, parent-report had high (>90%) sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy, while the youth-report had high specificity and PPV, moderate accuracy (81.4%), and lower sensitivity (69.8%) and NPV (67.3%). The ADHD module performed less well: parent-report had high NPV (91.4%), moderate sensitivity (80.8%), and lower specificity (71.6%), PPV (50.0%), and accuracy (74.0%); youth-report had moderate specificity (82.8%) and NPV (88.3%), and lower sensitivity (65.0%), PPV (54.2%), and accuracy (78.6%). Adding teacher-report of ADHD symptoms to DISC-5 parent-report of ADHD increased sensitivity (94.7%) and NPV (97.1%), but decreased specificity (64.2%), PPV (48.7%), and accuracy (72.2%). These findings support using the parent-report tic disorder module alone or in combination with the child report module in future research and epidemiologic studies; additional validation studies are warranted for the ADHD module.

Fine Motor Skills in Children with Tourette Syndrome and their Unaffected First-degree Siblings

Background

The exact etiology of Tourette Syndrome (TS) remains unclear, making the search for impaired neuropsychological functions possibly connected to the underlying cause of TS as important as it is challenging. One neuropsychological domain of interest is fine motor skills.

Method

This study compared fine motor skill performance on the Purdue Pegboard Task (PPT) in 18 children with TS, 24 unaffected first-degree siblings and 20 controls. A set of screening questionnaires was administered to determine comorbid psychiatric illness.

Results

Children with TS, their siblings and controls did not differ significantly in fine motor skills as measured with the PPT. Performance on the PPT was not correlated with tic severity; however, we found an inverse correlation with severity of attention-deficit/hyperactivity disorder (ADHD) symptoms, as assessed by parent reported ADHD symptoms. Children with TS were found to have significantly higher parent reported ADHD symptoms compared to controls, yet only two out of the 18 participants had been diagnosed with ADHD.

Conclusion

This study suggests that fine motor skill impairment in children with TS may be more strongly correlated with comorbid ADHD than to TS and tics.

Long-term efficacy, prognostic factors, and safety of deep brain stimulation in patients with refractory Tourette syndrome: A single center, single target, retrospective study

BACKGROUND

To evaluate the long-term efficacy, prognostic factors, and safety of posteroventral globus pallidus internus deep brain stimulation (DBS) in patients with refractory Tourette syndrome (RTS).

METHODS

This retrospective study recruited 61 patients with RTS who underwent posteroventral globus pallidus internus (GPi) DBS from January 2010 to December 2020 at the Chinese People's Liberation Army General Hospital. The Yale Global Tic Severity Scale (YGTSS), Yale-Brown Obsessive-Compulsive Scale (YBOCS), Beck Depression Inventory (BDI), Gilles de la Tourette Syndrome Quality-of-Life Scale (GTS-QOL) were used to evaluate the preoperative and postoperative clinical condition in all patients. Prognostic factors and adverse events following surgery were analyzed.

RESULTS

Patient follow up was conducted for an average of 73.33 ± 28.44 months. The final postoperative YGTSS (32.39 ± 22.34 vs 76.61 ± 17.07), YBOCS (11.26 ± 5.57 vs 18.31 ± 8.55), BDI (14.36 ± 8.16 vs 24.79 ± 11.03) and GTS-QOL (39.69 ± 18.29 vs 78.08 ± 14.52) scores at the end of the follow-up period were significantly lower than those before the surgery (p < 0.05). While age and the duration of follow-up were closely related to prognosis, the disease duration and gender were not. No serious adverse events were observed and only one patient exhibited symptomatic deterioration.

CONCLUSIONS

Posteroventral-GPI DBS provides long-term effectiveness, acceptable safety and can improve the quality of life in RTS patients. Moreover, DBS is more successful among younger patients and with longer treatment duration.

Association of Tourette Syndrome and Chronic Tic Disorder With Violent Assault and Criminal Convictions

Importance

Tic disorders are associated with multiple social adversities, but little is known about the experience of violent assault (including sexual assault) and criminality in this group.

Objective

To establish if Tourette syndrome (TS) and chronic tic disorder (CTD) are associated with an increased risk of experiencing violent assault and criminal convictions.

Design, Setting, and Participants

In this cohort study, all individuals living in Sweden at any time between January 1, 1973, and December 31, 2013, were identified from Swedish nationwide health and administrative registers. Cox proportional hazards regression models were used to estimate the risk of violent assault and criminal convictions among people with TS or CTD, compared with the general population and unaffected full siblings. Data analyses were conducted between September 1 and October 22, 2021.

Exposures

The Swedish version of the International Classification of Diseases, Eighth Revision (ICD-8), ICD-9, and ICD-10 diagnoses of TS or CTD in the Swedish National Patient Register.

Main Outcomes and Measures

Records of sexual and nonsexual violent assault and death due to violent assaults were obtained from the National Patient Register and the Cause of Death Register, respectively. Convictions for violent and nonviolent criminal offenses were obtained from the Crime Register. Covariates included sex and birth year.

Results

The study cohort included 13 819 284 individuals living in Sweden between 1973 and 2013. A total of 7791 individuals with TS or CTD were identified (median [IQR] age at first diagnosis, 13.4 [10.0-21.8] years; 5944 [76%] male). Compared with unaffected individuals from the general population, people with TS or CTD had a 2-fold increased risk of experiencing any violent assault (sexual and nonsexual) (adjusted hazard ratio [aHR], 2.21; 95% CI, 2.00-2.43), a 3-fold increased risk of violent convictions (aHR, 3.13; 95% CI, 2.92-3.36), and a 1.6-fold increased risk of nonviolent crime convictions (aHR, 1.62; 95% CI, 1.54-1.71). Among people with TS or CTD, 37.0% (114 of 308; 95% CI, 31.6%-42.4%) of individuals who had experienced violent assault also had a violent crime conviction, compared with 17.9% (16 067 of 89 920; 95% CI, 17.6%-18.1%) in the general population. Exclusion of individuals with attention-deficit/hyperactivity disorder and substance use disorders partially attenuated the associations. Similarly, within-sibling models attenuated but did not eliminate the associations (any violent assault: aHR, 1.32; 95% CI, 1.08-1.61; violent crime: aHR, 2.23; 95% CI, 1.86-2.67; nonviolent crime: aHR, 1.34; 95% CI, 1.20-1.50).

Conclusions and Relevance

Results of this cohort study suggest that most individuals with TS or CTD are not assaulted nor are perpetrators of crime. However, individuals with TS or CTD diagnosed in specialist settings were more likely to both experience violent assault and be perpetrators of violence compared with the general population. The risk was highest in individuals with comorbid attention-deficit/hyperactivity disorder and substance use disorders. The increased risk found in specialty clinics will need to be better understood in the general population.

Clinical precursors of tics: an EMTICS study

BACKGROUND

Children with Tourette syndrome (TS) often have comorbid disorders, particularly attention-deficit/hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD). While subtle premorbid symptoms have been described in various psychiatric disorders, the presence of clinical precursors that may exist before the onset of tics is unknown. This longitudinal study aimed to find clinical precursors of tics by assessing a range of clinical characteristics prior to tic onset in comparison with children without onset of tics.

METHODS

A sample of 187 3- to 10-year-old first-degree unaffected relatives of children with TS were followed up to 7 years in the European Multicentre Tics in Children Study (EMTICS). We investigated whether clinical characteristics assessed at baseline predicted tic onset, comparing 126 children without tic onset to 61 children who developed tics. We used the least absolute shrinkage and selection operator (LASSO) method, a penalised logistic regression approach. We also explored sex differences and repeated our analyses in an age- and sex-matched subsample.

RESULTS

Children with tic onset were more frequently male (β = -0.36), had higher baseline severity of conduct problems (β = 0.23), autism spectrum disorder symptoms (ASD; β = 0.08), compulsions (β = 0.02) and emotional problems (β = 0.03) compared to children without tic onset. Conduct and ASD problems were male-specific predictors, whereas severity of compulsions and oppositional (β = 0.39) and emotional problems were female-specific predictors.

CONCLUSION

This study supports the presence of clinical precursors prior to tic onset and highlights the need of sex-specific monitoring of children at risk of developing tics. This may aid in the earlier detection of tics, particularly in females. We moreover found that tics most often persisted one year after tic onset, in contrast to the common belief that tics are mostly transient.

Vitamin D levels in children and adolescents with chronic tic disorders: a multicentre study

This study investigated whether vitamin D is associated with the presence or severity of chronic tic disorders and their psychiatric comorbidities. This cross-sectional study compared serum 25-hydroxyvitamin D [25(OH)D] (ng/ml) levels among three groups: children and adolescents (3-16 years) with CTD (n = 327); first-degree relatives (3-10 years) of individuals with CTD who were assessed for a period of up to 7 years for possible onset of tics and developed tics within this period (n = 31); and first-degree relatives who did not develop tics and were ≥ 10 years old at their last assessment (n = 93). The relationship between 25(OH)D and the presence and severity of tics, as well as comorbid obsessive-compulsive disorder (OCD) and attention-deficit/hyperactivity disorder (ADHD), were analysed controlling for age, sex, season, centre, latitude, family relatedness, and comorbidities. When comparing the CTD cohort to the unaffected cohort, the observed result was contrary to the one expected: a 10 ng/ml increase in 25(OH)D was associated with higher odds of having CTD (OR 2.08, 95% CI 1.27-3.42, p < 0.01). There was no association between 25(OH)D and tic severity. However, a 10 ng/ml increase in 25(OH)D was associated with lower odds of having comorbid ADHD within the CTD cohort (OR 0.55, 95% CI 0.36-0.84, p = 0.01) and was inversely associated with ADHD symptom severity (β = - 2.52, 95% CI - 4.16-0.88, p < 0.01). In conclusion, lower vitamin D levels were not associated with a higher presence or severity of tics but were associated with the presence and severity of comorbid ADHD in children and adolescents with CTD.

LRRTM4 Terminal Exon Duplicated in Family with Tourette Syndrome, Autism and ADHD

Tourette syndrome (TS) is a neurodevelopmental disorder characterised by motor and vocal tics and strong association with autistic deficits, obsessive–compulsive disorder (OCD) and attention-deficit/hyperactivity disorder (ADHD). The genetic overlap between TS and autism spectrum disorder (ASD) includes those genes that encode the neurexin trans-synaptic connexus (NTSC) inclusive of the presynaptic neurexins (NRXNs) and postsynaptic neuroligins (NLGNs), cerebellin precursors (CBLNs in complex with the glutamate ionotropic receptor deltas (GRIDs)) and the leucine-rich repeat transmembrane proteins (LRRTMs). In this study, we report the first evidence of a TS and ASD association with yet another NTSC gene family member, namely LRRTM4. Duplication of the terminal exon of LRRTM4 was found in two females with TS from the same family (mother and daughter) in association with autistic traits and ASD.

Emotion regulation and tic disorders in children

Tic disorders (TD) are developmental neuropsychiatric conditions often accompanied by comorbid conditions, and psychosocial hardships for child and family. The etiology of tics is unknown, and is complex and multifactorial. Stress is known to aggravate tic expression as well as associated comorbidities. Consequently, this study focused on possible connections between stress, emotion regulation, tic expression, and related psychopathology. Sixty consecutive admissions were assessed for perceived stress, emotional dysregulation, severity of obsessions and compulsions, anxiety, depression, attention deficit disorder, and tic expression at a TD clinic, in a university affiliated pediatric hospital. The results indicated that stress and emotion dysregulation were significantly related to both tic expression and severity of comorbidities. We discuss the role of emotion regulation dimensions regarding TD and related psychopathology as well as the mediating role of emotion regulation, and how they may contribute to the development of improved therapies for children with TD.

Immunity and Gilles de la Tourette syndrome: A systematic review and meta-analysis of evidence for immune implications in Tourette syndrome

BACKGROUND AND PURPOSE

The neurobiology of Gilles de la Tourette syndrome (GTS) is known to involve corticostriatal loops possibly under genetic control. Less is known about possible environmental triggers of GTS. Specifically, immune-related events following possible environmental inducers have been evoked, but important controversies still exist. In this systematic review and meta-analysis, we looked for evidence in favor of such possibilities.

METHODS

We performed a systematic review and meta-analysis of all immunological data in PubMed.

RESULTS

We found large discrepancies concerning immune dysfunctions in GTS, and meta-analyzing cytokines data did not allow us to conclude there is an involvement of specific cytokines in GTS neurobiology. When looking specifically at pediatric autoimmune neuropsychiatric disorder associated with streptococcus/pediatric acute onset neuropsychiatric syndrome, we found some important evidence of a possible infectious involvement but in a limited number of studies. Our meta-analysis found an increased level of anti-streptolysin O antibodies in GTS patients, but the level of anti-DNase B antibodies was not increased.

CONCLUSIONS

Too many questions still exist to allow us to definitively reach the conclusion that there is an infectious and immunological etiology in GTS. Much work is still needed to elucidate the possible role of immunology in GTS neurobiology and to favor immunological treatment rather than classical treatment.

Comorbid chronic tic disorder and tourette syndrome in children requiring inpatient mental health treatment

OBJECTIVE

Children needing admission to an inpatient mental health unit often present with severe neuropsychiatric disorders characterised by complex psychopathology. We aimed to examine all admitted children with comorbid chronic tic disorder (CTD) and Tourette syndrome (TS) over a 10-year period and determine the clinical significance of these diagnoses.

METHOD

A retrospective, naturalistic study was conducted, comparing children with and without CTD/TS in terms of co-morbid diagnoses, medication use, access to education, aggression contributing to the admission, duration of admission, functional outcomes and satisfaction with treatment. Data were analysed using Chi-square/Fisher's exact test and t-test for categorical and continuous variables, respectively, and subsequently with unadjusted and adjusted linear and logistic regression analyses.

RESULTS

A relatively high proportion of children had co-morbid CTD/TS (19.7%). There was a significant association with co-morbid obsessive-compulsive disorder, intellectual disability and autism spectrum disorder but not attention deficit hyperactivity disorder. CTD/TS were associated with longer admissions even after adjustments for confounding but did not seem to be independently associated with other examined clinical characteristics.

CONCLUSIONS

The prevalence of CTD/TS in children needing inpatient treatment is significant. In our sample, comorbid CTD/TS seem to represent a marker of overall symptom severity as evidenced by longer admissions.

Deep brain stimulation in the management of paediatric neuropsychiatric conditions: Current evidence and future directions

INTRODUCTION

Neurosurgery has provided an alternative option for patients with refractory psychiatric indications. Lesion procedures were the initial techniques used, but deep brain stimulation (DBS) has the advantage of relative reversibility and adjustability. This review sets out to delineate the current evidence for DBS use in psychiatric conditions, with an emphasis on the paediatric population, highlighting pitfalls and opportunities.

METHODS

A systematic review of the literature was conducted on studies reporting the use of DBS in the management of psychiatric disorders. The PRISMA guidelines were employed to structure the review of the literature. Data was discussed focusing on the indications for DBS management of psychiatric conditions in the paediatric age group.

RESULTS

A total of seventy-three full-text papers reported the use of DBS surgery for the management of psychiatric conditions matching the inclusion criteria. The main indications were Tourette Syndrome (GTS) (15 studies), Obsessive Compulsive Disorder (OCD) (20), Treatment Resistant Depression (TRD) (27), Eating Disorders (ED) (7) and Aggressive Behaviour and self-harm (AB) (4). Out of these, only 11 studies included patients in the paediatric age group (≤18 years-old). Among the paediatric patients, the indications for surgery included GTS, AB and ED.

CONCLUSIONS

The application of deep brain stimulation for psychiatric indications has progressed at a steady pace in the adult population and at a much slower pace in the paediatric population. Future studies in children should be done in a trial setting with strict and robust criteria. A move towards personalising DBS therapy with new stimulation paradigms will provide new frontiers and possibilities in this growing field.

Phakic intraocular lens implantation in a case of Tourette syndrome exacerbated by wearing glasses and contact lenses

A 25-year-old longsighted woman presented with a history of spectacle and contact lens induced exacerbation of Tourette syndrome symptoms. Preoperatively, she had very poor unaided vision (6/60), achieving good (6/9) vision in both eyes with spectacle correction. The patient underwent bilateral simultaneous implantation of phakic implantable collamer lens (ICL) implants (STAAR, USA) which sit in front of the natural lens. Postoperatively, her uncorrected visual acuity was markedly improved as were her manifestations of Tourette syndrome. She achieved her full potential of unaided vision (6/9). This is the first documented case of Tourette syndrome triggered by glasses and contact lenses in which bilateral phakic toric lens implants were effective in improving vision and controlling motor symptoms. Phakic toric ICL implantation is a reversible technique for the correction of visually significant ametropia in selected patients and has improved this patient's quality of life.

Clinical Correlates of Health-Related Quality of Life in Adults With Chronic Tic Disorder

Tics are the hallmark feature of Tourette syndrome (TS), but psychiatric and sensory symptoms are widely prevalent and increasingly recognized as core manifestations of the disorder. Accumulating evidence suggests that these psychiatric and sensory symptoms exert greater influence on quality of life (QOL) than tics themselves. However, much remains uncertain about determinants of QOL in TS due to the complexity of the clinical presentation. Here, we sought to clarify the association between health-related QOL (HRQOL) and common psychiatric and sensory symptoms in adults with TS and other chronic tic disorders. To do so, we prospectively recruited 52 patients from a tertiary care clinic to complete self-report measures assessing HRQOL (Gilles de la Tourette-Quality of Life Scale, GTS-QOL), depression (Patient Health Questionnaire-9, PHQ-9), anxiety (Generalized Anxiety Disorder Scale-7, GAD-7), obsessive-compulsive symptoms (Dimensional Obsessive-Compulsive Scale, DOCS), attention deficit hyperactivity disorder symptoms (Adult ADHD Self-Report Screening Scale for DSM-5, ASRS-V), and premonitory urge (Premonitory Urge to Tic Scale, PUTS). All participants were also administered the Yale Global Tic Severity Scale (YGTSS) to quantify tic severity. Using correlational analysis and multivariable linear regression modeling, we found that GTS-QOL score was significantly associated with scores from all other rating scales, with the exception of the PUTS. GTS-QOL was most strongly associated with PHQ-9, followed by ASRS-V, GAD-7, DOCS, and YGTSS total tic score. The regression model including these five independent variables, as well as sex, explained 79% of GTS-QOL score variance [F _(6,40) = 29.6, p < 0.001]. Specific psychiatric symptoms differentially impacted physical, psychological, and cognitive HRQOL. Systematic assessment of psychiatric comorbidities is imperative for clinical care and clinical research efforts directed at improving QOL in adults with chronic tic disorders.

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.

Incidence of Autism Spectrum Disorder in Youths Affected by Gilles de la Tourette Syndrome Based on Data from a Large Single Italian Clinical Cohort

Gilles de la Tourette syndrome (GTS) and autism spectrum disorder (ASD) are etiologically related neurodevelopmental disorders with an onset age before 18 years and a reported comorbidity of 2.9–20%. The aim of the present study was to identify the incidence of ASD in a large clinical sample of individuals affected by GTS and to compare our results with previously reported incidences. We retrospectively analyzed clinical data (n = 1200) from January 2010 to March 2019 obtained from the outpatient Catania Tourette Clinic, part of the Child and Adolescent Neurology and Psychiatry of the Medical and Experimental Department of Catania University. We used internationally validated evaluation tools. The neuropsychological evaluation was carried out by an expert and a certificated team of child and adolescent neurologists, supervised by two expert child neurologists (R.R. and M.G.). We investigated 975 GTS-affected individuals of various socioeconomic levels aged 5–18 years, and 8.9% (n = 87) were affected by ASD. The incidence of GTS with ASD was significantly lower (p < 0.001) in children than in adolescents. No statistically significant differences were found in the sex distribution and age of onset of tics between individuals with GTS alone and those with GTS and ASD. The incidence of GTS and ASD comorbidity in this study was high, and this has several implications in terms of treatment and prognosis.

Effect of behavior therapy for Tourette's disorder on psychiatric symptoms and functioning in adults

BACKGROUND

Although behavior therapy reduces tic severity, it is unknown whether it improves co-occurring psychiatric symptoms and functional outcomes for adults with Tourette's disorder (TD). This information is essential for effective treatment planning. This study examined the effects of behavior therapy on psychiatric symptoms and functional outcomes in older adolescents and adults with TD.

METHOD

A total of 122 individuals with TD or a chronic tic disorder participated in a clinical trial comparing behavior therapy to psychoeducation and supportive therapy. At baseline, posttreatment, and follow-up visits, participants completed assessments of tic severity, co-occurring symptoms (inattention, impulsiveness, hyperactivity, anger, anxiety, depression, obsessions, and compulsions), and psychosocial functioning. We compared changes in tic severity, psychiatric symptoms, and functional outcomes using repeated measure and one-way analysis of variance.

RESULTS

At posttreatment, participants receiving behavior therapy reported greater reductions in obsessions compared to participants in supportive therapy ($\eta _p^2 $ = 0.04, p = 0.04). Across treatments, a positive treatment response on the Clinical Global Impression of Improvement scale was associated with a reduced disruption in family life ($\eta _p^2 $ = 0.05, p = 0.02) and improved functioning in a parental role ($\eta _p^2 $ = 0.37, p = 0.02). Participants who responded positively to eight sessions of behavior therapy had an improvement in tic severity ($\eta _p^2 $ = 0.75, p < 0.001), inattention ($\eta _p^2 $ = 0.48, p < 0.02), and functioning ($\eta _p^2 $ = 0.39-0.42, p < 0.03-0.04) at the 6-month follow-up.

CONCLUSION

Behavior therapy has a therapeutic benefit for co-occurring obsessive symptoms in the short-term, and reduces tic severity and disability in adults with TD over time. Additional treatments may be necessary to address co-occurring symptoms and improve functional outcomes.

Empiric Recurrence Risk Estimates for Chronic Tic Disorders: Implications for Genetic Counseling

Background: Tourette disorder (TD) and other chronic tic disorders are neurodevelopmental/neuropsychiatric disorders characterized by motor and/or vocal tics. Family studies indicate that TD strongly aggregates within families and that other chronic tic disorders are biologically related such that studies typically combine them into any chronic tic disorder (CTD). Because of stigma, bullying, and comorbidity with other neuropsychiatric disorders, CTDs can severely impact the quality of life of individuals with these disorders. Objectives: The genetic architecture of CTDs is complex and heterogeneous, involving a myriad of genetic variants. Thus, providing familial recurrence risks is based on empirical recurrence risk estimates rather than genetic testing. Because empiric recurrence risks for CTDs have not been published, the purpose of this study is to calculate and report these recurrence risks estimates. Methods: Based on population prevalence and increased risk to different relatives from a large population-based family study, we calculated the empiric recurrent risk estimate for each relative type (full sibling, parents, offspring, all first-degree, and all second-degree). Results: The recurrence risk estimate for CTDs in first-degree relatives is 29.9% [95% confidence interval (CI) = 23.2-38.5%]. The risk is higher in males, 33.7% (95% CI = 26.2-43.3%), than females, 24.3% (95% CI = 18.9-31.3%). Conclusions: Given the complex, heterogeneous genetic architecture of CTDs, individuals concerned about recurrence risk should be referred to genetic counseling. Such counseling should include discussion of the derivation and limitations of these empiric recurrence risk estimates, including the upper and lower limits of the range of risk.

Predictors of the Clinical Course of Tourette Syndrome: A Longitudinal Study

OBJECTIVE

Tourette syndrome (TS) is a chronic childhood neurodevelopmental disorder characterized by motor and vocal tics and frequent comorbidities. The clinical presentation of Tourette syndrome is heterogeneous and the prognosis for each individual child is difficult to define. This large prospective longitudinal study explores predictors in childhood of the clinical course of tics and comorbidities in early adulthood.

METHODS

The cohort was recruited at the Danish National Tourette Clinic. Data were collected at baseline (N = 314; ages, 5-19 years) and follow-up 6 years later (n = 227; ages, 11-26 years) to examine changes in the expression of tics and comorbidities. Childhood clinical factors, represented by 4 binary clinical outcomes, were selected as possible predictors of the clinical course of tics and comorbidities in early adulthood; these were tic severity and diagnoses of obsessive compulsive disorder (OCD), attention-deficit hyperactivity disorder (ADHD), and emotional disorders.

RESULTS

The strongest predictors of high tic scores, OCD, or ADHD diagnoses in early adulthood were the corresponding tic (odds ratio [OR]: 1.09), OCD (OR: 1.08), and ADHD (OR: 1.13) severity scores (per scale point) in childhood. Being female (OR: 3.94) and childhood ADHD severity (OR: 1.11) predicted future emotional disorders. Special education, genetic factors, and psychosocial factors were also predictive for the clinical course of Tourette syndrome.

CONCLUSION

We identified strong clinical predictors of Tourette syndrome-associated outcomes in early adulthood that are directly applicable to clinical Tourette syndrome populations and may help to guide new patients, plan early interventions, and implement preventive measures.

Economic evaluation of deep-brain stimulation for Tourette's syndrome: an initial exploration

BACKGROUND

Deep-brain stimulation (DBS) can be effective in controlling medically intractable symptoms of Tourette's syndrome (TS). There is no evidence to date, though, of the potential cost-effectiveness of DBS for this indication.

OBJECTIVE

To provide the first estimates of the likely cost-effectiveness of DBS in the treatment of severe TS.

METHODS

We conducted a cost-utility analysis using clinical data from 17 Australian patients receiving DBS. Direct medical costs for DBS using non-rechargeable and rechargeable batteries and for the alternative best medical treatment (BMT), and health utilities for BMT were sourced from the literature. Incremental cost-effectiveness ratios (ICERs) were estimated using a Markov models with a 10-year time horizon and 5% discount rate.

RESULTS

DBS increased quality-adjusted life year (QALY) gained from 2.76 to 4.60 over a 10-year time horizon. The ICER for DBS with non-rechargeable (rechargeable) batteries, compared to BMT, was A$33,838 (A$15,859) per QALY. The ICER estimates are sensitive to DBS costs and selected time horizon.

CONCLUSIONS

Our study indicates that DBS may be a cost-effective treatment for severe TS, based on the very limited clinical data available and under particular assumptions. While the limited availability of data presents a challenge, we also conduct sensitivity analyses to test the robustness of the results to the assumptions used in the analysis. We nevertheless recommend the implementation of randomised controlled trials that collect a comprehensive range of costs and the use of a widely accepted health-related quality of life instrument to enable more definitive statements about the cost-effectiveness of DBS for TS.

Deep brain stimulation for Gilles de la Tourette syndrome in children and youth: a meta-analysis with individual participant data

Objective

Gilles de la Tourette syndrome (GTS) is a disorder characterized by motor and vocal tics. Although by definition the onset of GTS is before age 18 years, clinical trials of deep brain stimulation (DBS) have been conducted only in adults. Using individual participant data (IPD) meta-analysis methodology, the current study investigated the safety and efficacy of DBS as a treatment for GTS in children and youth.

Methods

A systematic review with no date or language restrictions was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. Three electronic databases were searched: PubMed, EMBASE, and Web of Science. From 843 articles screened, the IPD of 58 children and youth (ages 12–21 years) extracted from 21 articles were collected and analyzed. A mixed-effects univariable analysis followed by multivariable hierarchical regression was performed using change in the Yale Global Tic Severity Scale (YGTSS) score as the primary outcome and reported measures of comorbidities as secondary outcomes.

Results

The authors’ results showed an average improvement of 57.5% ± 24.6% across studies on the YGTSS. They also found that comorbid depression and stimulation pulse width each correlated negatively with outcome (p < 0.05). In patients with less severe GTS, greater improvements were evident following thalamic stimulation. More than one-quarter (n = 16, 27.6%) of participants experienced side effects, the majority of which were minor.

Conclusions

DBS in the pediatric population may be an effective option with a moderate safety profile for treatment of GTS in carefully selected children and youth. Large, prospective studies with long-term follow-up are necessary to understand how DBS influences tic symptoms and may alter the natural course of GTS in children.

Interoceptive Accuracy in Youth with Tic Disorders: Exploring Links with Premonitory Urge, Anxiety and Quality of Life

Aberrant interoceptive accuracy could contribute to the co-occurrence of anxiety and premonitory urge in chronic tic disorders (CTD). If it can be manipulated through intervention, it would offer a transdiagnostic treatment target for tics and anxiety. Interoceptive accuracy was first assessed consistent with previous protocols and then re-assessed following an instruction attempting to experimentally enhance awareness. The CTD group demonstrated lower interoceptive accuracy than controls but, importantly, this group difference was no longer significant following instruction. In the CTD group, better interoceptive accuracy was associated with higher anxiety and lower quality of life, but not with premonitory urge. Aberrant interoceptive accuracy may represent an underlying trait in CTD that can be manipulated, and relates to anxiety and quality of life.

[A review on the management of tic disorders in children: psychoeducation and behavioral intervention]

Tic disorders (TD) are a group of neurodevelopmental disorders that are characterized by motor and/or vocal tics in children and adolescents. The etiology and pathogenesis of TD remain unclear, and it is believed to be caused by a combination of genetic, biological, psychological, and environmental factors. The major treatment for TD includes psychoeducation, behavioral intervention, and drug treatment. To further explore the management of TD, this article reviews the research advances in psychoeducation and behavioral intervention for patients with TD.

Systematic review of co-occurring OCD and TD: Evidence for a tic-related OCD subtype?

OBJECTIVE

The aim of this review is to summarize the current knowledge of associated features of co-occurring obsessive-compulsive disorder (OCD) and tic disorders (TD) and to critically evaluate hypotheses regarding the nature of their comorbidity.

METHOD

We conducted a systematic review following PRISMA guidelines. To this aim, the PubMed, PsychInfo and ISI Web of Knowledge databases were searched up to August 30, 2018. For gender and age-of-onset we additionally conducted meta-analyses.

RESULTS

One hundred eighty-nine studies met inclusion criteria. We substantiate some acknowledged features and report evidence for differential biological mechanisms and treatment response. In general, studies were of limited methodological quality.

CONCLUSIONS

Several specific features are reliable associated with co-occurring OCD + TD. The field lacks methodological sound studies. The review found evidence against and in favor for different hypotheses regarding the nature of comorbidity of OCD and TD. This could indicate the existence of a stepwise model of co-morbidity, or could be an artefact of the low methodological quality of studies.

Disentangling Tourette syndrome heterogeneity through hierarchical ascendant clustering

AIM

To explore the heterogeneity of Tourette syndrome as part of a neurodevelopmental spectrum.

METHOD

Using hierarchical ascendant clustering based on tic symptoms, developmental milestones, and neurodevelopmental comorbidities, we analyzed the heterogeneity of Tourette syndrome phenotypes in a sample of 174 children and adolescents with Tourette syndrome referred to a tertiary university clinic.

RESULTS

The model yielded three distinct clusters characterized as follows. In cluster 1, we found many neurodevelopmental comorbidities (including intellectual disabilities, autism spectrum disorder, attention-deficit-hyperactivity disorder [ADHD], and learning disabilities) and academic impairments. In cluster 2, patients had no other neurodevelopmental comorbidities. In cluster 3, patients had higher intelligence, a high frequency of attentional impairment, school problems related to both ADHD and unspecific attention difficulties, and handwriting problems related to the tics themselves. Interestingly, clusters did not differ in terms of family history or anxious-depressive comorbidities. The only other differences that emerged were related to prenatal or perinatal risk factors (more represented in cluster 1) and treatment profiles (higher rates of stimulants in cluster 1).

INTERPRETATION

We conclude that from a phenotypical perspective, Tourette syndrome is a heterogeneous syndrome with at least three main clusters that may help in addressing the etiological basis of Tourette syndrome and specific rehabilitative and therapeutic approaches.

WHAT THIS PAPER ADDS

The clustering of Tourette syndrome based on comorbidity with other neurodevelopmental conditions reveals three clusters. A group of patients with Tourette syndrome show school difficulties related to non-specific attention and writing problems. Analysing only children and adolescents helps to distinguish between developmental comorbid conditions and coexistent disorders.

Behavioral fragmentation in the D1CT-7 mouse model of Tourette's syndrome

AIM

The transgenic D1CT-7 mouse is one of the best-characterized animal models of Tourette's syndrome (TS), exhibiting spontaneous tic-like Head-Body Twitches (HBT) and deficits in sensorimotor gating. This study is aimed at evaluating the behavioral dynamics of these mutants and their potential relevance to TS.

METHODS

The behavior of D1CT-7 and Wild Type littermates was firstly assessed by considering frequencies and durations. To detect recurrent real-time behavioral sequences, the multivariate T-pattern analysis was employed. Analyses of transition probabilities among behaviors further provided an overall picture of the behavioral dynamics.

RESULTS

T-patterns and transition matrices revealed in D1CT-7 mice a clear-cut hyperactivity compared to controls, with a lower behavioral organization and a marked shift from cautious sniffing toward locomotion. Moreover, the behavioral patterns of the transgenic mice were pervasively disturbed by intrusive tic-like HBT leading to a marked fragmentation of the behavior. Novel exposure to open field provoked a transient inhibitory control over the disrupting phenotype.

CONCLUSION

The results of this study show that the D1CT-7 mouse model is subjected to a behavioral fragmentation, with repercussions going beyond the simple tic-like phenomenon. These phenotypes are strikingly akin to behavioral problems observed in patients with TS and further validate the power of this model in summarizing pivotal behavioral aspects of TS.

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.

Phenotype Development in Adolescents With Tourette Syndrome: A Large Clinical Longitudinal Study

Tourette syndrome (TS) is a neurodevelopmental disorder characterized by frequent comorbidities and a wide spectrum of phenotype presentations. This study aimed to describe the development of phenotypes in TS and tic-related impairment in a large longitudinal study of 226 children and adolescents followed up after 6 years. The participants were clinically examined to assess tic severity and impairment, obsessive compulsive disorder (OCD), and attention-deficit/hyperactivity disorder (ADHD). The development in phenotypes changed toward less comorbidity with 40% TS-only (no OCD or ADHD) (TS without OCD or ADHD) at baseline and 55% at follow-up.Tic-related impairment was expected to improve with an age-related tic decline, but surprisingly the impairment score did not reflect the tic decline. Sex, vocal and motor tics, and OCD and ADHD severity were highly significantly correlated to the impairment score. Knowledge of TS phenotype development is used in clinical settings to guide patients and for genetic, etiological, and clinical research purposes.

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.

The English Version of the Gilles de la Tourette Syndrome-Quality of Life Scale for Children and Adolescents (C&A-GTS-QOL)

Gilles de la Tourette syndrome is a chronic neuropsychiatric disorder that can have a detrimental impact on the health-related quality of life of children with the condition. To date no patient-reported health-related quality of life measures have been developed for children and adolescents in the English language. This study validated the first disease-specific scale for the quantitative assessment of health-related quality of life in 118 children and adolescents with Gilles de la Tourette syndrome (C&A-GTS-QOL) following language adaptation from Italian to English in the United Kingdom. Standard statistical methods were used to test the psychometric properties of the rating scale. Principal component factor analyses led to the identification of six health-related quality of life domains (cognitive, copro-phenomena, psychological, physical, obsessive-compulsive, and activities of daily living), explaining 66.7% of the overall variance. The C&A-GTS-QOL demonstrated satisfactory scaling assumptions and acceptability; validity was supported by interscale correlations (range 0.2-0.7), confirmatory factor analysis, and correlation patterns with other rating scales and clinical variables.

"I swear it is Tourette's!": On functional coprolalia and other tic-like vocalizations

Coprolalia in neuropsychiatry is typically associated with tic disorders, in particular Gilles de la Tourette syndrome. To date, there has been no report of functional coprolalia. Here, we provide the clinical characteristics of 13 adolescent and adult patients with coprolalic and other functional tic-like complex vocalizations who, on the basis of these symptoms, were misdiagnosed with a primary tic disorder, most commonly Gilles de la Tourette syndrome. We describe similarities and highlight the differences from primary tic disorders in order to provide a pragmatic list of clinical clues that will facilitate correct diagnostic labeling and thereby treatment. Finally, we emphasize that the distinction between a primary and a functional tic disorder should rely on a combination of neuropsychiatric symptoms and signs and not on the presence of single, however striking, abnormal behaviors, such as coprolalia.

Comorbidities, Social Impact, and Quality of Life in Tourette Syndrome

Tourette syndrome (TS) is more than having motor and vocal tics, and this review will examine the varied comorbidities as well as the social impact and quality of life (QoL) in individuals with TS. The relationship between any individual and his/her environment is complex, and this is further exaggerated in the case of a person with TS. For example, tics may play a significant role in shaping the person's experiences, perceptions, and interactions with the environment. Furthermore, associated clinical features, comorbidities, and coexisting psychopathologies may compound or alter this relationship. In this regard, the common comorbidities include attention-deficit hyperactivity disorder and disruptive behaviors, obsessive compulsive disorder, and autism spectrum disorder, and coexistent problems include anxiety, depression, and low self-esteem, which can all lead to poorer psychosocial functioning and QoL. Thus, the symptoms of TS and the associated comorbid conditions may interact to result in a vicious cycle or a downward spiraling of negative experiences and poor QoL. The stigma and social maladjustment in TS and the social exclusion, bullying, and discrimination are considered to be caused in large part by misperceptions of the disorder by teachers, peers, and the wider community. Improved community and professional awareness about TS and related comorbidities and other psychopathologies as well as the provision of multidisciplinary services to meet the complex needs of this clinical population are critical. Future research to inform the risk and resilience factors for successful long-term outcomes is also warranted.