LONG-TERM OUTCOME IN PEDIATRIC TRICHOTILLOMANIA

The genetics of trichotillomania and excoriation disorder: A systematic review

BACKGROUND

Trichotillomania (TTM) and excoriation disorder (ED) are impairing obsessive-compulsive related disorders that are common in the general population and for which there are no clear first-line medications, highlighting the need to better understand the underlying biology of these disorders to inform treatments. Given the importance of genetics in obsessive-compulsive disorder (OCD), evaluating genetic factors underlying TTM and ED may advance knowledge about the pathophysiology of these body-focused repetitive behaviors.

AIM

In this systematic review, we summarize the available evidence on the genetics of TTM and ED and highlight gaps in the field warranting further research.

METHOD

We systematically searched Embase, PsycInfo, PubMed, Medline, Scopus, and Web of Science for original studies in genetic epidemiology (family or twin studies) and molecular genetics (candidate gene and genome-wide) published up to June 2023.

RESULTS

Of the 3536 records identified, 109 studies were included in this review. These studies indicated that genetic factors play an important role in the development of TTM and ED, some of which may be shared across the OCD spectrum, but there are no known high-confidence specific genetic risk factors for either TTM or ED.

CONCLUSIONS

Our review underscores the need for additional genome-wide research conducted on the genetics of TTM and ED, for instance, genome-wide association and whole-genome/whole-exome DNA sequencing studies. Recent advances in genomics have led to the discovery of risk genes in several psychiatric disorders, including related conditions such as OCD, but to date, TTM and ED have remained understudied.

The association between trichotillomania symptoms and emotion regulation difficulties: A systematic review and meta-analysis

BACKGROUND

Emotion regulation is postulated to play an important role in Trichotillomania (TTM). Whilst a growing number of studies have examined the relationship between emotion regulation difficulties and TTM symptoms, there have been no attempts to evaluate the overall strength of this association or the quality of the evidence base.

METHOD

This systematic review and meta-analysis aimed to synthesise findings from studies that have examined the relationship between emotion regulation difficulties and TTM symptoms, to inform future TTM treatment targets. We identified 17 studies that met inclusion criteria. From these studies, 32 correlation coefficients were extracted for meta-analysis. The Joanna Briggs Institute Checklist for Analytical Cross Sectional Studies was used to assess risk of bias amongst the included studies.

RESULTS

There was a moderately sized association between TTM symptoms and ER difficulties, (r adjusted = 0.32, 95 % CI [0.28, 0.37], t = 15.58 (df = 11.86), p < 0.0001) that was moderated by sample size (F(df1 = 1, df2 = 30) = 4.597, b = -0.0001, SE = 0.0001, 95 % CI [-0.0002; 0.0000], p = 0.040) and differences between types of emotion regulation measures (Q(df = 1) = 4.06, p = 0.044).

LIMITATIONS

The data analysed was correlational, therefore causality was unable to be determined. Comorbidities were not able to be examined as a moderator.

CONCLUSION

This study provided a preliminary integration of the evidence and demonstrated that individuals with higher levels of TTM severity appear to exhibit decreased overall emotion regulation abilities and strategies.

Characteristics of trichotillomania and excoriation disorder across the lifespan

Trichotillomania (hair-pulling disorder) and excoriation (skin-picking) disorder are body-focused repetitive behaviors, which often first present in adolescence and cause distress and impairment into adulthood. Few studies have examined the clinical characteristics of the co-occurrence of these conditions across the lifespan. We examined cross-sectional survey responses collected from April 2018-February 2020 to evaluate the relationship between trichotillomania, excoriation disorder, and their co-occurrence. Responses from individuals with trichotillomania (n = 50), excoriation disorder (n = 52), and both conditions (n = 50) ages 4-67 years old were compared for co-occurring conditions and current symptoms. Self-report measures of hair-pulling and skin-picking severity and subtypes were assessed. Gender, race, and co-occurring conditions were generally similarly distributed across the three groups with high rates of self-reported anxiety (63-82%), depression (34-50%), obsessive-compulsive disorder (16-29%), and attention-deficit/hyperactivity disorder (12-32%). Among individuals with both trichotillomania and excoriation disorder, significant positive correlations were observed between hair-pulling and skin-picking severity scores as well as hair-pulling and skin-picking subtypes. Hair-pulling and skin-picking severity peaked at the transition from adolescence to adulthood and hair-pulling/skin-picking styles appeared to shift across the lifespan. Our results support several similarities between trichotillomania and excoriation disorder, providing new insight into the clinical characteristics of these conditions.

Sociodemographic variables, clinical characteristics, and treatments in children with trichotillomania in terms of age and gender: a multicenter study

OBJECTIVE

Although trichotillomania (TTM) is a common, typically pediatric-onset disorder, data on the phenomenology of TTM in children, accompanying comorbid psychiatric disorders, and treatment options are extremely limited. In our study, it was aimed to investigate these variables and related factors in patients undergoing psychiatric evaluation and follow-up.

METHOD

The study included 79 children and adolescents between the ages of 4 and 17 who were diagnosed with TTM and followed up in four different Child and Adolescent Psychiatry outpatient clinics between 2015 and 2020. The sociodemographic characteristics of these patients, clinical features of the disease, comorbid psychiatric disorders, and treatment approaches have been studied.

RESULTS

Our results showed that TTM was more common in girls, hair and eyebrow plucking was the most common, and symptoms and features accompanying TTM changed with age, but not with gender. Again, 79.7% of these children had at least one psychiatric comorbid disorder (most common being anxiety disorders and Attention Deficit/Hyperactivity Disorder), comorbidity was closely related to TTM severity, 93.7% used at least one pharmacotherapeutic agent, and positive response rates to treatment were found to be low. Moreover, TTM severity was found to increase with age and disease duration.

CONCLUSION

Study findings support that clinical presentation, disease severity and comorbidity rates may change with age in children and adolescents with TTM, and early intervention is important to prevent clinical progression/worsening and mental health sequela.

Mitochondrial modulators for obsessive-compulsive and related disorders: a systematic review and meta-analysis

It remains unclear whether mitochondrial modulators (MMs) are beneficial in the treatment of obsessive-compulsive and related disorders. Thus, in an attempt to answer this clinical question, we performed a systematic review and a random-effects meta-analysis of double-blind, randomized, placebo-controlled trials. The primary outcome was change in overall symptoms as measured using standardized rating scales. Other outcomes were response to treatment; improvement in anxiety-related scales scores, depression-related scale scores, Clinical Global Impression Severity Scale (CGI-S) scores, and Sheehan Disability Scale (SDS) scores; all-cause discontinuation; and individual adverse events. We calculated the standardized mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confidence intervals. We reviewed 17 studies (n = 629, 72.62% female; duration = 2-20 weeks; mean age = 30.47 years) of MMs: eicosapentaenoic acid (K = 1), folic acid (K = 1), lithium (K = 1), N-acetylcysteine (K = 10), inositol (K = 3), and silymarin (K = 1). MMs outperformed placebo in overall improvement in symptoms (p < 0.01) and in improving anxiety-related scale scores (p = 0.05). Subgroup analysis of individual MMs revealed that although overall symptoms were better improved by N-acetylcysteine (p < 0.01) and lithium (p = 0.04), no MMs outperformed placebo in terms of improving anxiety-related scale scores. Neither pooled nor individual MMs outperformed placebo in improving response to treatment, depression-related scale scores, CGI-S scores, SDS scores, or all-cause discontinuation. N-acetylcysteine was no more associated with a higher incidence of individual adverse events including gastrointestinal symptoms, than placebo. In conclusion, N-acetylcysteine was beneficial in the treatment of obsessive-compulsive and related disorders. However, further study with larger samples is necessary to confirm this finding.

The Potential of N-Acetylcysteine for Treatment of Trichotillomania, Excoriation Disorder, Onychophagia, and Onychotillomania: An Updated Literature Review

BACKGROUND

Trichotillomania (TTM), excoriation disorder, onychophagia, and onychotillomania are categorized as body focused repetitive behavior (BFRB) disorders, causing damage to the skin, hair, and/or nails with clinically significant psychosocial consequences. Currently, there are no standardized treatments for these compulsive, self-induced disorders. Studies on treatment of these disorders using psychotropic drugs (i.e., selective serotonin reuptake inhibitors, tricyclic antidepressants, anticonvulsants) have shown variable efficacy. Recently, there is a growing interest in N-acetylcysteine (NAC) for treating BFRBs. NAC is a glutamate modulator that has shown promise in successfully reducing the compulsive behaviors in BFRB disorders. This article provides an updated review of the literature on the use of NAC in TTM, excoriation disorder, onychophagia, and onychotillomania.

METHODS

Relevant articles were searched in the PubMed/MEDLINE database.

RESULTS

Twenty-four clinical trials, retrospective cohort studies, and case reports assessing the efficacy of NAC in TTM, excoriation disorder, and onychophagia were included. No studies for onychotillomania were found in our search.

CONCLUSIONS

Although NAC has proven successful for treatment of BFRB disorders, data is derived from few clinical trials and case reports assessing small numbers of patients. Larger studies with longer durations are needed to fully establish the efficacy of NAC in these disorders.

Review of the diagnosis and management of pediatric psychodermatologic conditions: Part I

Pediatric psychodermatologic conditions encompass both primary dermatologic conditions with psychiatric comorbidities and primary psychiatric conditions with self-induced dermatologic manifestations. Detection, diagnosis, and management of primary psychiatric conditions with dermatologic manifestations are challenging due to patient-perceived stigma and lack of educational opportunities for dermatology providers. This two-part series highlights the most up-to-date evidence-based data and management techniques of some of the more common dermatoses of primary psychiatric conditions in children. Part I includes trichotillomania, skin-picking disorder, and onychophagia, and part II covers dermatitis artefacta, body dysmorphic disorder, and delusions of parasitosis by proxy, with special considerations for family dynamics.

Automatic and focused hair pulling in trichotillomania: Valid and useful subtypes?

Prior work suggested that trichotillomania may have four subtypes based on the extent to which pulling is automatic or focused in nature. 238 adults with trichotillomania undertook clinical and cognitive assessments and were assigned into four subtypes based on k-means clustering of Milwaukee Inventory for Subtypes of Trichotillomania-Adult Version (MIST-A) scores. We examined whether a cluster solution was apparent using conventional metrics. Based on prior literature, we then force-fitted a four subtype model (low-low, low-high, high-low, high-high). Subtypes were compared and validity of the MIST-A subtyping approach was evaluated. A cluster solution did not converge based on conventional metrics. Following force-fitting, subtypes did not differ on demographic variables, age at symptom onset, nor duration of illness. The high-focused high-automatic subtype had worse symptom severity than other subtypes. Co-morbid depression was more common in the low-focused low-automatic and high-focused low-automatic subtypes. This study suggests that MIST-A subtypes may not be valid or clinically useful based on several issues. First, k-means models indicated that the MIST-A data did not generate any cluster solutions. Second, when a forced cluster solution was fitted, the subtypes did not differ on the vast majority of measures. Third, force-fitting four subtypes yielded findings that were logically inconsistent (e.g. worse quality of life in one group, but higher rates of comorbid anxiety/depression in others). Overall, we suggest that both focused and automatic pulling may characterize the same pulling episode, or certainly the same person across episodes. Thus they may be clinically relevant variables, but not forming coherent subtypes.

The Influence of Hair Pulling Styles in the Treatment of Trichotillomania

This report investigated the improvement in Automatic and Focused styles of hair pulling among youth with trichotillomania (TTM). Youth with TTM (N = 40) participated in a clinical trial that compared habit reversal training (HRT) to treatment-as-usual (TAU). Participants completed a baseline assessment to characterize hair pulling severity, self-reported hair pulling styles, and co-occurring psychiatric conditions. Youth were randomly assigned to receive eight weekly sessions of HRT or eight weeks of TAU. Afterward, youth completed a post-treatment assessment of hair pulling severity and hair pulling styles. Youth in the TAU condition then received eight weekly sessions of HRT and completed another post-treatment assessment. Analyses revealed that the Focused pulling style largely improved with HRT (d = 0.73) compared to TAU (d = 0.11). However, there was limited improvement for the Automatic pulling style following either HRT (d = 0.10) or TAU (d = -0.31). This same pattern of effects was also found during open-label treatment with HRT. Although behavior therapies such as HRT are the principle treatment for youth with TTM, the Automatic pulling style exhibited limited improvement to this therapeutic approach. Therefore, therapeutic strategies that enhance awareness to pulling behaviors may produce more robust outcomes to behavior therapy for youth with TTM.

Sensory symptoms in body-focused repetitive behaviors, restless legs syndrome, and Tourette syndrome: An overlap?

Tourette syndrome (TS) is a neurodevelopmental condition characterized by multiple tics. Sensory symptoms play a key role in the clinical phenomenology and pathophysiology of TS, as most patients report premonitory urges driving tic expression. Interestingly, sensory symptoms have also been reported in other conditions characterized by repeated behaviors. This review explores the nature of sensory symptoms reported by patients with body focused repetitive behaviors (BFRBs, especially trichotillomania and skin picking disorder) and restless legs syndrome (RLS) in comparison to TS. A sense of mounting inner tension and reinforcement mechanisms driven by gratification and relief on expression of the tic or repetitive behavior appear to be implicated across all conditions. Subjective urges can be temporarily suppressed by patients with TS and selected BFRBs, whereas patients with RLS tend to report dysesthesia more frequently than a suppressible urge to move. The observed similarities in the phenomenology of sensory symptoms across these conditions raise the possibility of a comparable underlying pathophysiology. Preliminary findings suggest an overlap of neural pathways encompassing the insula, basal ganglia (putamen), and posterior cingulate cortex.

Trichotillomania is more related to Tourette disorder than to obsessive-compulsive disorder

OBJECTIVE

Trichotillomania (TTM) is characterized by the pulling out of one's hair. TTM was classified as an impulse control disorder in DSM-IV, but is now classified in the obsessive-compulsive related disorders section of DSM-5. Classification for TTM remains an open question, especially considering its impact on treatment of the disorder. In this review, we questioned the relation of TTM to tic disorder and obsessive-compulsive disorder (OCD).

METHOD

We reviewed relevant MEDLINE-indexed articles on clinical, neuropsychological, neurobiological, and therapeutic aspects of trichotillomania, OCD, and tic disorders.

RESULTS

Our review found a closer relationship between TTM and tic disorder from neurobiological (especially imaging) and therapeutic standpoints.

CONCLUSION

We sought to challenge the DSM-5 classification of TTM and to compare TTM with both OCD and tic disorder. Some discrepancies between TTM and tic disorders notwithstanding, several arguments are in favor of a closer relationship between these two disorders than between TTM and OCD, especially when considering implications for therapy. This consideration is essential for patients.

Autism and trichotillomania in an adolescent boy

An adolescent with autism spectrum disorder and improperly treated attention deficit hyperactivity disorder presented with recurrent hair pulling. Treatment with selective serotonin reuptake inhibitor and stimulant improved these conditions.

Initial psychometrics, outcomes, and correlates of the Repetitive Body Focused Behavior Scale: Examination in a sample of youth with anxiety and/or obsessive-compulsive disorder

BACKGROUND

Body-Focused Repetitive Behaviors (BFRBs), including skin-picking, hair-pulling, and nail-biting, commonly occur in youth, even at elevated/problematic levels, and are associated with a number of other psychiatric symptoms. The present study examined the internal consistency of a brief screening tool for BFRBs as well as the prevalence, severity, and correlates of BFRBs in a sample of youth with a primary anxiety or obsessive-compulsive disorder (OCD).

METHODS

Ninety-three youth-parent dyads presenting for treatment for anxiety or OCD completed study measures including the Repetitive Body Focused Behavior Scale - Parent (RBFBS), which includes subscales for skin-picking, hair-pulling, and nail-biting, as well as a number of additional clinician-, parent-, and child-rated scales.

RESULTS

The RBFBS demonstrated good to excellent internal consistency. BFRBs were endorsed in 55% of youths, with elevated levels in 27%. Skin-picking was the most common BFRB (38%), followed by nail-biting (34%) and hair-pulling (4%). Youth with BFRBs, as compared to those without, were rated as more avoidant by their parents. Among those with BFRBs, more avoidant tendencies, anxiety sensitivity, and child-rated panic, separation, and generalized anxiety symptoms were associated with elevated BFRB severity. BFRBs were equally common but more likely to be elevated among youth with a primary anxiety, than OCD, diagnosis.

DISCUSSION

Results provide initial support for the RBFBS as a brief screening tool for the three common BFRBs. In addition, the results suggest avoidant tendencies and physical manifestations of distress may be particularly relevant to the escalation of BFRB symptoms in youth.

Preliminary Randomized Controlled Trial of Habit Reversal Training for Treatment of Hair Pulling in Youth

OBJECTIVES

This study evaluated the treatment efficacy of habit reversal training (HRT) relative to treatment as usual (TAU) for children and adolescents aged 7-17 years with a primary diagnosis of trichotillomania (TTM).

METHOD

An initial assessment consisting of semistructured interviews and rating scales was conducted. Participants (N = 40, 85% female) meeting diagnostic criteria for TTM were randomized to either 8 weekly sessions of HRT by trained therapists or 8 weeks of TAU. One week after the final HRT session or final TAU week, patients completed a posttreatment assessment, followed by 1- and 3-month follow-up assessments. All assessments were conducted by a trained rater who was blinded to treatment condition.

RESULTS

The group by time analysis of variance yielded a significant interaction on the National Institute of Mental Health-Trichotillomania Severity Scale Total Score (F_1,38 = 16.47, p < 0.001, η²_p = 0.30). The mean score decreased from 12.67 ± 4.60 at baseline to 5.62 ± 4.38 at posttreatment in the HRT group (t₂₀ = 5.99, p < 0.001, d = 1.31), whereas the TAU group changed from 10.42 ± 4.35 to 9.32 ± 4.11 (t₁₈ = 1.34, p = 0.20, d = 0.31). The Massachusetts General Hospital-Hair Pulling Scale Total Score decreased from 15.14 ± 3.86 at baseline to 7.14 ± 5.54 at posttreatment in the HRT group (t₂₀ = 6.16, p < 0.001, d = 1.34); the TAU group changed from 14.16 ± 4.51 to 12.26 ± 4.34 (t₁₈ = 1.50, p = 0.15, d = 0.34). On the Clinical Global Impressions-Improvement, 16/21 participants (76%) were rated as treatment responders in the HRT group versus 4/19 (21%) in the TAU group (χ² = 12.13, p < 0.001, V = 0.55). At 1-month follow-up, 10-12 treatment responders who completed the assessment maintained improvement. At 3-month follow-up, six of eight maintained improvement.

CONCLUSIONS

HRT can be an effective treatment for TTM in youth.