[Pruritus and stress: psychoneuroimmunological mechanisms, assessment of psychosocial stress, and therapeutic implications].

BACKGROUND

Chronic pruritus (CP) represents one of the most common and therapeutically challenging symptoms in dermatological care. Its relationship with psychosocial and symptom-related stress is bidirectional and clinically highly relevant: pruritus is significantly associated with psychosocial stress via the brain-skin axis and can be simultaneously exacerbated by psychosocial stress. At the behavioral level, scratching perpetuates this cycle.

METHODS

This overview summarizes the current state of knowledge on psychoneuroimmunology in the context of pruritus, presents validated assessment instruments, and describes stress-modulating treatment approaches.

RESULTS

Psychosocial and symptom-related stress influence the activation of mast cells and other inflammatory target cells via the hypothalamic-pituitary-adrenal axis (HPA) and the sympathetic nervous system as well as through the release of neuropeptides and neurotrophins (e.g., SP, CGRP, CRH, NGF). This leads to disturbances of the epidermal barrier function, neurogenic inflammation, and cytokine imbalances in the skin. Validated instruments such as the Perceived Stress Scale (PSS) are suitable to assess chronic psychosocial stress. In addition to the widely used ItchyQoL scale to assess symptom-specific stress, transsymptomatic instruments and the Pruritus-associated Stress Scale (PASS) which was specifically developed to measure pruritus-related stress are suitable. Given that symptom relief is often insufficient under purely pharmacological treatment, interventions aimed to improve the management of psychosocial stressors serve as an effective adjunct to dermatological care and improve treatment outcomes and patient satisfaction.

CONCLUSION

In the biopsychosocial understanding of disease, stress plays an important role in the development and persistence of pruritus. Depending on the individual patient, psychosocial stressors, symptom-specific stressors, or a combination of both may predominate. The differential diagnostic assessment of stressors allows an individualized evaluation and recommendation of appropriate psychosocial interventions as a part of integrated psychodermatological care for CP.