Self-induced nail disorders (SINDs): What do we know so far?

Self-induced nail disorders are a broad group of different clinical manifestations that share the common trait of being caused more or less voluntarily by the patient. These are distinct conditions within the clinical spectrum of onychotillomania. Most patients diagnosed with these disorders have psychiatric co-morbidities, and a multidisciplinary approach is thus highly recommended. The purpose of this review is to describe the most common clinical features encountered during daily nail consultations and to provide useful diagnostic tools and therapeutic tips for the best approach to these conditions.

Body Focused Repetitive Behavior Disorders: Behavioral Models and Neurobiological Mechanisms. / Beden Odakli Tekrarlayici Davranis Bozukluklari: Davranis Modelleri ve Nörobiyolojik Mekanizmalar.

OBJECTIVE: Body Focused Repetitive Behaviors (BFRB) is an umbrella term for undesirable, repetitive motor activities such as Trichotillomania (TTM), Skin Picking Disorder (SPD), nail biting, cheek chewing, lip biting, finger sucking, finger cracking and teeth grinding. Such behaviors are engaged in to eliminate a part of the body and may result in impaired functionality. The frequency of presentation to clinicians is low since BFRB are defined as harmless, although the number of studies on this condition has increased rapidly recently, including those making a clear determination of epidemiological data, those investigating the etiopathogenesis and those providing treatment guidelines, although they remain inadequate. The present study provides a review of studies investigating the etiology of BFRB to date. METHOD: Articles published between 1992 and 2021 stored in the Pubmed, Medline, Scopus and Web of Science databases were reviewed, and the prominent research studies of the condition identified were included in the evaluation. RESULTS: Studies investigating the etiopathogenesis of BFRB were found in most cases to investigate adult populations, and were hampered by such confounding factors as clinical heterogeneity, high rates of comorbid psychiatric diseases and small sample sizes. The identified studies reveal that attempts have been made to explain BFRB based on behavioral models, and that the condition is inherited at a high rate. Treatment planning is mostly associated with monoamine systems (especially glutamate and dopamine) and interventions were directed to addiction elements. Furthermore, cognitive flexibility and motor inhibition defects in neurocognitive area and cortico-striato-thalamocortical cycle abnormalities in neuroimaging studies have been reported. CONCLUSION: Studies investigating the clinical features, incidence, etiopathogenesis and treatment of BFRB, which holds a controversial place in psychiatric classification systems, would contribute to a better understanding of the disease and a more appropriate definition of the condition.

Emotion regulation deficits in persons with body-focused repetitive behavior disorders.

BACKGROUND: Conceptualizations of emotion dysregulation (ED) and body-focused repetitive behavior disorders (BFRBDs) imply that ED may be a central component of BFRBDs as well as a factor that distinguishes BFRBDs from non-impairing, subclinical body-focused repetitive behaviors (BFRBs). The current study empirically tested these observations. METHODS: One hundred thirty-eight undergraduates (of 1900 who completed a screening survey) completed self-report measures assessing four emotion regulation (ER) deficits hypothesized to underlie ED (alexithymia, maladaptive emotional reactivity, experiential avoidance, and response inhibition when distressed); 34 of these participants had BFRBDs, 64 had subclinical BFRBs, and 42 were unaffected by BFRBs. RESULTS: Results indicated that participants with BFRBDs reported higher levels of maladaptive emotional reactivity, experiential avoidance, and response inhibition when distressed than participants with subclinical BFRBs and participants unaffected by BFRBs. These results held even when controlling for comorbidity and total number of reported BFRBs. Participants did not differ on alexithymia. LIMITATIONS: Limitations of the current study include the BFRB groups' different distributions of BFRB types (e.g., hair pulling versus skin picking), the sample's demographic uniformity, and the fact that negative affectivity was not controlled when exploring BFRB group differences on ER deficits. Future research should improve on these limitations. CONCLUSIONS: The current results suggest that ED is a factor that differentiates BFRBDs from subclinical BFRBs. Such results may be useful for generating hypotheses regarding mechanisms responsible for BFRBs' development into BFRBDs. Furthermore, these results may provide insight into factors that explain the efficacy of more contemporary behavioral treatments for BFRBDs.