Sleep functioning in adults with trichotillomania (hair-pulling disorder), excoriation (skin-picking) disorder, and a non-affected comparison sample

Impact of sleep disruption on BDD symptoms and treatment response

BACKGROUND

Body dysmorphic disorder (BDD) is severe, undertreated, and relatively common. Although gold-standard cognitive behavioral therapy (CBT) for BDD has strong empirical support, a significant number of patients do not respond. More work is needed to understand BDD's etiology and modifiable barriers to treatment response. Given its high prevalence and impact on the development, maintenance, and treatment of related, frequently comorbid disorders, sleep disruption is a compelling, but not-yet studied factor.

METHODS

Data were drawn from a randomized controlled trial of guided smartphone app-based CBT for BDD. Included participants were offered 12-weeks of treatment, immediately (n = 40) or after a 12-week waitlist (n = 37). Sleep disruption and BDD symptom severity were assessed at baseline, week-6, and week-12.

RESULTS

Hypotheses and analysis plan were pre-registered. Two-thirds of patients reported significant insomnia symptoms at baseline. Baseline severity of sleep disruption and BDD symptoms were not related (r = 0.02). Pre-treatment sleep disruption did not predict BDD symptom reduction across treatment, nor did early sleep improvements predict greater BDD symptom improvement. Early BDD symptom improvement also did not predict later improvements in sleep.

LIMITATIONS

Limitations include the small sample, restricted ranges of BDD symptom severity and treatment response, and few metrics of sleep disruption.

CONCLUSIONS

Although insomnia was disproportionately high in this sample and both BDD symptoms and sleep improved in treatment, results suggest sleep and BDD symptoms may function largely independent of one another. More work is encouraged to replicate and better understand findings as well as potential challenges and benefits of addressing sleep in BDD.

Clinical Characteristics, Sleep, and Temperament in Infants and Young Children with Problematic Hair Pulling and Skin Picking

Background

This study examined clinical characteristics of problematic hair pulling (HP) and skin picking (SP) in infants and young children and their association with self-soothing, sleep, and temperament.

Methods

An internet survey of parents/caregivers of 0-5-year-olds (n = 384 with data analyzed, of whom 26 experienced HP, 62 experienced SP, and 302 were controls free of HP and SP) assessed demographics and medical history, HP and SP characteristics, contextual factors, self-soothing, sleep patterns, and temperament. Participants were recruited through both HP and SP advocacy and support webpages and general webpages (e.g., parenting groups). Descriptive statistics, chi-square tests of independence, independent samples t-test clinically characterized HP, SP, and control groups. Logistic regression and one-way analysis of covariance controlled for sex and age in analyses.

Results

HP and SP rates were 6.1% (n = 26) and 14.5% (n = 62), respectively. SP presented in 23.1% of children with HP, and HP presented in 9.7% of children with SP. Mean HP and SP onset occurred at 12.2 (SD = 11.2) and 24.1 (SD = 15.8) months, respectively. Contextual factors, including boredom, upset, and awake-in-bed were common in HP and SP. Common caregiver responses included distracting the child, moving the hand away, and telling the child to stop. Few caregivers sought professional help for the child. Children with HP engaged in more hair twirling than controls, and children with SP engaged in more nail biting than controls. Children with HP, but not SP, had more sleep disturbance than controls. In terms of temperament, children with HP displayed sensitivity to stimuli, children with SP exhibited low persistence, and both HP and SP groups displayed serious, observant mood relative to controls.

Conclusions

Findings expand clinical understanding of HP and SP in children aged 0-5 and provide targets (contextual factors, sleep, sensory sensitivity, persistence, and mood) for behavioral interventions. Low rates of treatment seeking highlight the need for expansion of clinical guidelines for HP and SP in this age range.

Sleep Disturbances in Pediatric Body-Focused Repetitive Behaviors: A Preliminary Investigation

Body-focused repetitive behaviors (BFRBs) are repeated actions to one's body resulting in physical damage. Limited research has examined sleep, a known factor in psychological health, within the context of pediatric BFRBs. The current study sought to explore the connection between disordered sleep and BFRBs in a community sample. Aim 1 of the study was to determine the predictive power of group membership [control group (no BFRB symptoms reported), subthreshold BFRB group (mild BFRB symptoms reported; severity score of 2 or less out of 9), and those with symptoms characteristic of BFRBs (more than mild BFRB symptoms reported; severity score of 3 or higher out of 9)] for level of sleep disturbance. A hierarchical regression revealed that there was a significant effect of group membership after controlling for anxiety (F (3, 410) = 152.976, p < .001). Aim 2 of the study was to test whether there was a relationship between sleep disturbance and BFRB severity. The hierarchical regression revealed that at Step 1, anxiety accounted for 23.1% of the variance in BFRB severity (β = 0.48, t = 8.87, p < 0.001). At Step 2, sleep disturbance total score accounted for an additional 7.2% of the variance, suggesting this variable makes a unique contribution to overall BFRB severity (SDSC: β = 0.40, t = 5.18, p < 0.001). The findings of this study suggest that sleep could be a clinical factor to consider when conceptualizing a child with BFRBs.

Sleep quality and its clinical associations in trichotillomania and skin picking disorder

BACKGROUND

Trichotillomania (TTM) is characterized by recurrent hair pulling and associated hair loss. Skin picking disorder (SPD) is characterized by recurrent skin picking and associated scarring or tissue damage. Both disorders are also accompanied by psychological distress and poor sleep. Very little, however, is known about lifestyle variables that may contribute to symptom severity in these disorders.

METHODS

We recruited 87 adults as part of a cross-sectional study of 3 groups (TTM, SPD, and non-affected). Clinical subjects (n=69) were compared with controls (n=18) on sleep quality as measured by Pittsburgh Sleep Quality Index (PSQI). We used partial least squares regression to identify which variables were significantly associated with poor sleep quality among those participants with TTM or SPD.

RESULTS

Clinical subjects had significantly poorer sleep quality than controls. Sleep quality was significantly related to older age, worse perceived stress, lower distress tolerance and greater impulsivity in adults with BFRBs. Poor sleep quality was associated with worse hair pulling symptom severity but not skin picking severity. Higher levels of comorbid mental disorders was also associated with worse sleep, above and beyond the impact of these other variables.

CONCLSUIONS

Poor sleep quality appears to be related to multiple variables. Further research is needed to determine causality and to tailor treatment to specific patient needs.

Should skin picking disorder be considered a diagnostic category? A systematic review of the evidence

OBJECTIVES

The aim of this study was to conduct a systematic review of the literature to collect, analyse and synthesise the evidence on skin picking disorder as defined by Arnold's criteria or the Diagnostic and Statistical Manual of Mental Disorders - fifth edition (DSM-5) and to examine whether skin picking disorder warrants inclusion in the DSM-5 as a distinct disorder.

METHOD

The databases CINAHL, Medline, Embase and PsycINFO were searched for articles published between January 2008 and May 2018. Eligible articles were empirical studies that used Arnold's or DSM-5 criteria to diagnose skin picking disorder, published in English, with participants aged 18 years or older. The methodological quality of included studies was assessed according to the National Health and Medical Research Council's guidelines and suggested nosological classification of skin picking disorder were summarised. Eligible studies were assessed against the five criteria proposed by Blashfield and colleagues to determine the validity of the inclusion of skin picking disorder in the DSM-5.

RESULTS

A total of 20 studies were considered eligible out of 1554. Most of the papers were case-control studies with small clinical samples. Only one out of Blashfield's five criteria was met; there were commonly accepted diagnostic criteria and assessment scales present in the literature. However, at the time of review, the criterion of 50 published articles (25 of which are required to be empirical) was not met; there had been no publication specifically assessing the clinical utility or validity of skin picking disorder and no studies addressing the differentiation of skin picking disorder from other obsessive-compulsive and related disorders.

CONCLUSION

Only a small proportion of published studies on skin picking disorder have employed validated criteria. The current literature fulfills only one of Blashfield's five criteria for the inclusion of skin picking disorder as a specific entity in psychiatric diagnostic manuals. Further empirical studies on skin picking disorder are needed in order to substantiate skin picking disorder as a disorder distinct from related disorders under the obsessive-compulsive and related disorders category.

Disentangling Reward Processing in Trichotillomania: 'Wanting' and 'Liking' Hair Pulling Have Distinct Clinical Correlates

Trichotillomania (TTM; hair-pulling disorder) is characterized by an irresistible urge or desire to pull out one's own hair, and a sense of pleasure when hair is pulled out. Evidence from translational neuroscience has shown that 'wanting' (motivation to seek a reward) and 'liking' (enjoyment when reward is received) are each mediated by overlapping but distinct neural circuitry, and that 'wanting' contributes to addictive/compulsive behaviors more so than 'liking'. In the present study, we developed the Hair Pulling Reward Scale (HPRS), a self-report measure that consists of two subscales designed to assess (a) cue-triggered urges and appetitive motivation to pull hair (i.e., putative correlates of 'wanting'), and (b) momentary pleasure and gratification during pulling episodes (i.e., putative correlates of 'liking'). We administered the HPRS to 259 individuals with TTM and examined its psychometric properties. Confirmatory factor analysis supported a two-factor model reflecting correlated Wanting and Liking scales. Consistent with predictions, Wanting, much more than Liking, had robust correlations with TTM severity, impulsiveness, difficulties in emotion regulation, psychiatric symptoms, and sleep dysfunction. The results suggest that the HPRS is a psychometrically sound instrument that can be used as a symptom-level measure of reward processing in TTM.

Confirmatory factor analysis of the SLEEP-50 Questionnaire in Trichotillomania (Hair-Pulling Disorder) and Excoriation (Skin-Picking) Disorder

The study objective was to perform a confirmatory factor analysis of the SLEEP-50 Questionnaire (SLEEP-50) in Trichotillomania (Hair-Pulling Disorder) and Excoriation (Skin-Picking) Disorder and compare sleep complaints in adults with Trichotillomania, Excoriation Disorder and non-affected controls. Participants were 234 adults with Trichotillomania, 170 with Excoriation Disorder, and 146 non-affected controls. Participants rated sleep using the SLEEP-50 and Pittsburgh Sleep Quality Index (PSQI). Confirmatory factor analysis was used to assess fit of the originally-proposed SLEEP-50 factors within Trichotillomania and Excoriation Disorder. Findings revealed acceptable to good fit of the original factors. Internal consistency was excellent in Trichotillomania and good in Excoriation Disorder for the total score and poor to good for subscales. Convergent validity was strong for the total and weak to strong for subscales in both groups. Findings suggest greater sleep complaints in Trichotillomania and Excoriation Disorder than in the general population. Trichotillomania and Excoriation Disorder groups reported greater rates of sleep apnea, narcolepsy, restless leg syndrome/periodic limb movement disorder, circadian rhythms sleep disorder, and sleep-related affective disorder relative to controls. There were no significant differences for insomnia, sleep state misperception, sleepwalking, nightmares, or hypersomnia. Results underscore the importance of clinical assessment of sleep disorders in Trichotillomania and Excoriation Disorder.

Sensory over-responsivity in trichotillomania (hair-pulling disorder)

OBJECTIVE

This study was an initial investigation of sensory-over responsivity (SOR) to external sensations among individuals with trichotillomania (TTM).

METHODS

Adults endorsing DSM-5 TTM criteria (N = 609) and a non-affected comparison sample (N = 268) completed a self-report survey.

RESULTS

The majority of the TTM group endorsed SOR symptoms; three-quarters endorsed at least mild tactile and auditory SOR. About 15% endorsed SOR symptoms in the severe to extreme range. TTM participants had significantly higher mean scores in both auditory (t (652.89) = -6.51, p < .001, d = .45) and tactile (t (655.24) = -8.38, p < .001, d = .58) modalities than comparison participants, with medium effect sizes. Greater levels of SOR were related to greater levels of perfectionism and by-proxy pulling urges. SOR was significantly and positively correlated with functional impairment when controlling for TTM severity.

CONCLUSION

This study expands prior work in obsessive-compulsive related disorders by contributing the first data about associations between TTM and over-responsivity to external sensations. Findings collectively suggest SOR may be related to maladaptive emotion regulation processes in TTM. A novel measure of SOR was developed and administered in this study.