Cognitive training in patients with Trichotillomania (Hair-pulling Disorder)

Louw, Derine (2019-04)

Thesis (PhD)--Stellenbosch University, 2019.

Thesis

ENGLISH SUMMARY : Background: Hair-pulling disorder (HPD), also known as trichotillomania, is a psychiatric condition characterized by recurrent pulling of hair, resulting in hair loss. Patients report repeated but unsuccessful attempts to reduce or stop the behaviour, leading to significant distress, and in some cases, functional impairment. HPD is characterized by impairments in executive functioning including working memory (WM), impulse control (IC) and emotional regulation (ER). Current interventions include Habit Reversal Therapy (HRT) and pharmacotherapy, but a large proportion of patients do not have access to these treatments or do not respond favourably. An easily accessible strategy in the context of scant resources would be particularly welcome. Based on the efficacy of WM training in improving executive functioning, it was hypothesized that this intervention would 1) be efficacious for reducing the symptoms of HPD, 2) improve compromised neurocognitive functions, 3) and be experienced by patients as an acceptable and feasible method of intervention. Methods: A single-blind, randomized, 5-week, 25-session cognitive working memory training (CWMT) program versus a control condition was conducted in 30 participants with a primary diagnosis of HPD. The primary outcome measure was the Massachusetts General Hospital Hair-Pulling Scale (MGH-HPS). The control condition required puzzle building, i.e. the Jigsaw Puzzles program available on the Internet, following the same 5-week protocol as the CWMT, commercially known as the Cogmed Working Memory Training. Assessments at baseline, immediate post-intervention, and at 3-month follow-up, provided information on clinical and neurocognitive data. Both quantitative and qualitative methods were employed. The quantitative data addressed hypotheses relating to treatment intervention outcomes and were analysed using Statistica 13.3. The qualitative data investigated the experience of living with HPD and addressed the acceptability and feasibility of the intervention and were analysed using Atlas.ti 8.1.30. Statistical analysis of the primary outcome and the neurocognitive data were conducted using mixed model repeated measures analysis of variance (ANOVA). The qualitative data were analyzed using a thematic approach. Results: CWMT significantly decreased hair-pulling severity compared to the control condition at 5 weeks and 3 months. Although participants did not demonstrate notable impairments in WM compared with norms, WM improved immediately post-training. Although gains in symptoms and WM were maintained at 3 months, there was no longer a significant difference between the cognitive training and control group. There were no impairments in IC and ER at baseline, and CWMT did not have greater impact on IC and ER than the control condition. Qualitatively, participants indicated that CWMT was feasible and acceptable; furthermore, participation in the study was associated with greater openness about symptoms at home, feeling less isolated, and feeling more supported. Conclusions: This is the first study of CWMT in HPD and demonstrates not only the feasibility and acceptability of this intervention, but also its efficacy. Further work is needed to study the relevant mechanisms, and to assess the effectiveness and cost-efficiency of this intervention in larger pragmatic trials aimed at scaling-up the intervention.

AFRIKAANSE OPSOMMING : Agtergrond: Haar-uittreksteuring (HUS), ook bekend as trichotillomanie, is ‘n psigiatriese toestand gekenmerk deur die herhaaldelike uittrek van hare, gepaardgaande met haarverlies. Pasiënte rapporteer herhaaldelike maar onsuksesvolle pogings om die gedrag te verminder of te stop, wat lei tot beduidende distres en, in sommige gevalle, funksionele inperking. HUS word gekenmerk deur probleme in uitvoerende funksies, insluitend werksgeheue (WG), impulsbeheer (IB) en emosie-regulering (ER). Huidige intervensies sluit in “Habit Reversal Therapy” (HRT) en farmakoterapie, maar ‘n groot hoeveelheid pasiënte het nie toegang tot hierdie behandelings, of reageer nie gunstig daarop nie. ‘n Maklik toeganklike strategie in die konteks van beperkte bronne sal verwelkom word. Gebaseer op die doeltreffenheid van WG-opleiding in die verbetering van uitvoerende funksies, is die hipoteses gestel dat hierdie intervensie 1) doeltreffend sal wees vir die vermindering van simptome in HUS, 2) spesifieke neurokognitiewe funksies sal verbeter, en 3) deur pasiënte ervaar sal word as ‘n aanvaarbare en haalbare intervensie-metode. Metodes: ‘n Enkel-blinde, ewekansige, 5-week, 25 sessie kognitiewe werksgeheue-opleidingsprogram (KWGO) versus ‘n kontrole-intervensie, is uitgevoer met 30 deelnemers met ‘n primêre diagnose van HUS. Die primêre uitkoms-instrument was die “Massachusetts General Hospital Hair-Pulling Scale” (MGH-HPS). Die kontrole-intervensie het legkaartbou naamlik die “Jigsaw Puzzles” program, beskikbaar op die Internet, behels, wat dieselfde 5-weke protokol gevolg het as die KWGO, kommersieël bekend as “Cogmed Working Memory Training”. Evaluering by basislyn, onmiddellik post-intervensie, en tydens 3-maande-opvolg het inligting oor kliniese en neurokognitiewe data voorsien. Beide kwantitatiewe en kwalitatiewe metodes is gebruik. Die kwantitatiewe data het die hipoteses verwant aan die behandelingsuitkomstes aangespreek, en is geanaliseer met behulp van Statistica 13.3. Die kwalitatiewe data het die ervaring van om te lewe met HUS ondersoek en die aanvaarbaarheid en haalbaarheid van die intervensie aangespreek en is geanaliseer met behulp van Atlas.ti 8.1.30. Statistiese analise van die primêre uitkoms en die neurokognitiewe data is uitgevoer deur gebruik te maak van die gemengde-model herhaalde metings “analysis of covariance” (ANOVA). Die kwalitatiewe data is geanaliseer deur gebruik te maak van die tematiese benadering. Resultate: KWGO het haar-uittrek-simptome beduidend verminder in vergelyking met die kontrole-intervensie by 5 weke en 3 maande. Alhoewel deelnemers nie merkbare probleme in WG demonstreer het in vergelyking met die norm nie, het WG onmiddellik post-opleiding verbeter. Alhoewel verbetering in haar-uittrek-simptome en WG behou is by 3 maande, was daar nie meer ‘n beduidende verskil tussen die opleidingsgroep en die kontrolegroep se prestasie nie. Daar was geen probleme met IB en ER by basislyn nie, en KWGO het nie ‘n groter impak op IB en ER as die kontrole-intervensie gehad nie. Kwalitatief geassosieer, het deelnemers aangedui dat KWGO aanvaarbaar en haalbaar was en ook dat die deelname aan die studie geassosieer was met meer openlikheid tuis oor simptome, en het gevoelens van verminderde isolasie en verhoogde ondersteuning teweeg gebring. Gevolgtrekkings: Hierdie is die eerste studie van KWGO in HUS en demonstreer nie net die aanvaarbaarheid en haalbaarheid van die intervensie nie, maar ook die doeltreffendheid daarvan. Verdere werk word benodig om die relevante meganismes hiervan te bestudeer, en om die doeltreffendheid en koste-effektiwiteit van hierdie intervensie te assesseer met groter pragmatiese studies wat verbetering van die intervensie ten doel het.

Please refer to this item in SUNScholar by using the following persistent URL: http://hdl.handle.net/10019.1/105796
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