Plain English Science: Sleep Functioning in Adults with Trichotillomania or Excoriation Disorder by Joseph Toles

A first-of-its-kind study conducted by researchers at the UCLA and the University of Wisconsin was released this January a study analyzing relationship between sleep functioning and trichotillomania (TTM) and excoriation disorder (ExD). The study, Sleep functioning in adults with trichotillomania (hair-pulling disorder), excoriation (skin-picking) disorder, and a non-affected comparison sample, published in the Journal of Obsessive-Compulsive and Related Disorders, compared trends in over four hundred people with TTM or ExD and nearly 150 healthy control subjects, making it possibly the largest study of BFRBs and sleep to date.

The study recruited participants online, screened for eligibility, then administered a battery of sleep TTM/ExD-related questions. While online self-reporting can potentially result in selection and self-diagnosis biases as compared to surveys conducted clinically, such marvels of the internet age like SurveyMonkey have undoubtedly contributed to humanity’s ability to do science at a 21st century pace. ​

TTM and ExD groups reported similar sleep impairment scores, which were both higher than the comparison group.

It is unclear whether skin picking/hair pulling leads directly to sleep disturbance or if these behaviors cause anxiety and depression, which in turn lead to sleep disturbance.

Similarly, it is possible that insufficient sleep contributes to the development or maintenance of BFRBD symptoms in vulnerable individuals

One quarter (24.1%) of hair pullers reported that more than half of daily pulling episodes occurred during sleep.

On average, 29.31% of daily hair pulling episodes and 18.19% of daily skin picking episodes occurred during sleep

When asked, “What makes it hard to stop pulling out your hair (picking your skin) after getting into bed but before falling asleep? In both groups, the most frequent response was “I zone out and pull my hair (pick my skin) without thinking about what I am doing.”

80% of the TTM group and 82% of the ExD group engaged in hair pulling and skin picking before sleep.

Skin picking during sleep appears more problematic than hair pulling during sleep. Picking in this context may be associated with increased nocturnal itching, thought to be related to circadian patterns of body temperature regulation.

The findings conclude that comprehensive treatment for TTM and ExD should include assessments for contributing sleep-related factors. Current assessment tools for BFRBs do not include items regarding sleep and clinicians should explicitly inquire about sleep patterns and address triggering environmental factors.The authors suggest wearing protective clothing like gloves or long sleeves to sleep if necessary and in severe cases of sleep-related BFRBD, undergoing polysomnography to assess underlying dysregulation in sleep maintenance processes. Patients can also receivemedication or behavioral interventions to address sleep disturbance or anxiety.Like many other psychology fields, BFRB research is becoming more cross-disciplinary as evidence emerges linking conditions in different fields. While this study only produced correlations between TTM, ExD, and sleep, correlation is the first step toward discovering causation and then treatments. Encouragingly, this study has given clear evidence that assessment of sleep disturbances should be included in comprehensive BFRB assessments in order to give a more complete view of the condition’s effect on patents’ quality of life and general well-being.