Background Body dysmorphic disorder (BDD) is a common psychiatric disorder associated with high costs for healthcare systems as patients may repeatedly ask for different, often not effective interventions. BDD symptoms are more prevalent in patients with dermatological conditions than the general population, but there are no large sample studies comparing the prevalence of BDD symptoms between patients with dermatological conditions and healthy skin controls. Objectives To compare the prevalence of BDD symptoms between patients with different dermatological conditions and healthy skin controls and to describe sociodemographic, physical and psychological factors associated with BDD symptoms to identify patients who may have a particularly high chance of having this condition. Methods This observational cross-sectional, comparative multi-centre study included 8295 participants: 5487 consecutive patients with different skin diseases (56% female) recruited among dermatological out-patients at 22 clinics in 17 European countries and 2808 healthy skin controls (66% female). All patients were examined by a dermatologist. BDD symptoms were assessed by the Dysmorphic Concern Questionnaire (DCQ). Sociodemographic data, information on psychological factors and physical conditions were collected. Each patient was given a dermatological diagnosis according to ICD-10 by a dermatologist. Results The participation rate of invited dermatological patients was 82.4% on average across all centres. BDD symptoms were five times more prevalent in patients with dermatological conditions than in healthy skin controls (10.5% vs. 2.1%). Patients with hyperhidrosis, alopecia and vitiligo had a more than eleven-fold increased chance (adjusted Odds Ratio (OR) > 11) of having BDD symptoms compared to healthy skin controls, and patients with atopic dermatitis, psoriasis, acne, hidradenitis suppurativa, prurigo and bullous diseases had a more than six-fold increased chance (adjusted OR > 6) of having BDD symptoms. Using a logistic regression model, BDD symptoms were significantly related to lower age, female sex, higher psychological stress and feelings of stigmatisation. Conclusions This study reveals that clinical BDD symptoms are significantly associated with common dermatological diseases. As such symptoms are associated with higher levels of psychological distress and multiple unhelpful consultations, general practitioners and dermatologists should consider BDD and refer patients when identified to an appropriate service for BDD screening and management.

The boundary between Dermatology and Psychiatry has increasing recognition. Psoriasis is a common psychophysiological skin disease with a major impact on patient's quality of life and a paradigmatic example of a pathology in that boundary. Studies are needed to exactly point out the prevalence of specific psychopathology and mental disorders associated with psoriasis. This work intends to analyse the prevalence of psychopathology and psychiatric comorbidities in patients with psoriasis. A systematic review of the literature was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the "5S" model proposed by Haynes. From all the papers retrieved by this search, a total of 34 papers met the inclusion criteria and were then deeply analysed. The most prevalent mental disorders in these patients are sleep disorders (average prevalence: 62.0%), sexual dysfunction (45.6%), personality (35.0%), anxiety (30.4%), adjustment (29.0%), depressive (27.6%) and substance-related and addictive disorders (24.8%). Other mental disorders have been less described, namely somatic symptoms and related disorders, schizophrenia and other psychoses, bipolar disorder and eating disorders. This updated research shows that the prevalence of psychiatric conditions in psoriasis may range from 24% to 90%. The study of the mind-skin connection in psoriasis may improve the knowledge about psoriasis and its psychiatric comorbidities. The link between psoriasis and associated mental disorders is frequently forgotten or not considered in the clinical practice. Psychiatric disorders in patients with psoriasis may be underdiagnosed. These patients would really benefit from psychiatric assessment, with therapeutic relevance.

Introduction: Several classifications of psychodermatology disorders have been proposed, with most of them based on two to four main disorder category groups. However, there is, to date, no classification that has resulted from a consensus established by psychodermatology experts. The DSM‐5‐TR (Diagnostic and statistical manual of mental disorders (5th ed.), Text Revision) and the ICD‐11 (International classification of diseases (11th revision)) also do not provide a systematized approach of psychodermatology disorders. Taking into consideration that classifications are a key pillar for a comprehensive approach to the pathologies of each branch of medicine, the proposal of a classification in psychodermatology appeared as a central need for the recognition of psychodermatological disorders, in an attempt to improve their recognition and, in that sense, to find a common language for the development of this subspecialty that crosses dermatology and psychiatry.Methods: Previously published classifications in psychodermatology were critically reviewed and discussed by expert opinion from an international multidisciplinary panel of 16 experts in psychodermatology and a new classification system is proposed, considering classical concepts in general dermatology and psychopathology.Results: Two main categories of disorders are presented (a main group related to primary mental health disorders and another main group related to primary skin disorders), which are subsequently subdivided into subgroups considering pathophysiological and phenomenological similarities, including key aspects of dermatological examination, namely the presence of visible skin lesions (primary and secondary skin lesions) and psychopathological correlates.Conclusion: This new classification aims to unify previous classifications, systematize the disorders that belong to psychodermatology and highlight their tenuous boundaries, to improve their management. It has been built and approved by the Psychodermatology Task Force of the European Academy of Dermatology and Venereology (EADV), the European Society for Dermatology and Psychiatry (ESDaP) and the Association for Psychoneurocutaneous Medicine of North America (APMNA).