Introduction and objective: Psoriasis is a chronic skin disease with a high impact on self-esteem and patients' health-related quality of life. In the last decades some studies have pointed out mental disorders associated with psoriasis and the etiopathogenic mechanisms behind that co-existence. This work compiles psychopathology associated with psoriasis and further analyzes the etiopathogenesis of psoriasis and mental disorders.
Methods: A systematic review of the literature was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and using the "5S" levels of organization of evidence from healthcare research, as previously described.
Results: Psoriasis is linked with many mental disorders, both in the psychotic and neurotic sprectrum. Chronic stress diminishes hypothalamic-pituitary-adrenal axis and upregulates sympathetic-adrenal-medullary responses, stimulating pro-inflammatory cytokines. Then, it maintains and exacerbates psoriasis and some of its mental disorders. High levels of pro-inflammatory cytokines connect psoriasis, psychiatric conditions, and other comorbidities of psoriasis (such as atherosclerosis) within a vicious cycle. Furthermore, the etiopathogenesis of the link between each psychiatric comorbidity and psoriasis has its own subtleties, including the cooccurrence of other comorbidities, the parts of the body affected by psoriasis, treatments, and biological and psychosocial factors.
Conclusion: The study of psychopathology can amplify our understanding about the etiopathogenesis of psoriasis and associated mental disorders. Patients would benefit from a psychodermatologic approach. The adequate treatment should take into account the mental disorders associated with psoriasis as well as the circumstances under which they occur.