Abstract

Functional somatic syndrome is a term used to refer to physical symptoms that are poorly explained. It encompass disorders such as chronic fatigue syndrome, fibromyalgia, chronic widespread pain, temporomandibular disorder, irritable bowel syndrome, lower back pain, tension headache, atypical face pain, non-cardiac chest pain, insomnia, palpitation, dyspepsia, and dizziness. General overlap exists between this term, somatization, and somatoform.

Signs and symptoms

Functional somatic syndrome is characterized by ambiguous, non-specific symptoms that appear in otherwise-healthy populations. Overlap exists in different syndromes, including gastrointestinal issues, pain, fatigue, cognitive difficulties, and sleep difficulties. Some have proposed to group symptoms into clusters or into one general functional somatic disorder given the finding of correlations between symptoms and underlying etiologies.

Cause and pathophysiology

Psychological trauma or stress appears to predispose persons to a functional somatic syndrome. HPA axis, autonomic nervous system, and immune response to stress has been proposed as a mediating mechanism. Upper airway resistance syndrome may also be implicated.

Treatment

Treatment may involve investigation, reassurance and explanation, and possibly specialist treatment such as antidepressants or cognitive behavioral therapy.

Epidemiology

Functional somatic syndromes may occur in 6 to 36% of the population.