[Chronic fatigue syndrome--a functional somatic syndrome]

Area of Science:

• Medical Psychology
• Psychosomatic Medicine
• Neuroimmunology

Background:

• Chronic fatigue is classified as a functional somatic syndrome (FSS), sharing preconditions, triggers, and maintaining factors with other FSS disorders.
• Subsyndromal chronic fatigue episodes are frequent and clinically similar to neurasthenia and chronic fatigue syndrome.
• While a single cause is absent, characteristic patterns in neurohumoral and immunological interactions, including HPA-axis dysfunction and neurocognitive sensitization, are observed in chronic fatigue syndrome.

Purpose of the Study:

• To explore the nature of chronic fatigue as a medical-psychiatric interface disorder.
• To identify key pathophysiological mechanisms and maintaining factors in chronic fatigue.
• To evaluate evidence-based therapeutic strategies for chronic fatigue management.

Main Methods:

• Review of existing literature on functional somatic syndromes and chronic fatigue.
• Analysis of neurohumoral, immunological, and neurocognitive findings.
• Evaluation of therapeutic intervention evidence.

Main Results:

• Chronic fatigue involves complex interactions within the HPA-axis and other regulatory systems, alongside heightened neuronal and neurocognitive sensitization.
• Increased critical appraisal of somatic functions and dysfunctional coping strategies are significant maintaining factors.
• Therapeutic approaches emphasizing patient activation, such as cognitive behavioral therapy and graduated activation, demonstrate good evidence for efficacy.

Conclusions:

• Chronic fatigue is a multifactorial condition best understood as a medical-psychiatric interface disorder.
• Effective management requires addressing neurobiological underpinnings and psychological maintaining factors.
• Patient-centered, active therapies are crucial for successful treatment outcomes, with antidepressants offering limited adjunctive benefits.