Stress-Related Diseases and Functional Somatic Syndromes

Due to changes in social and medical structures, the structure of diseases is also changing. Somatic symptoms persist, but no abnormalities are found in regular medical examinations, and medical approaches are difficult to be effective. Functional somatic diseases are one of the so-called “stress-related diseases”, but the characteristic is that there are problems with function (activity) rather than visible morphological abnormalities. Such diseases are called
functional somatic syndrome (FSS).

Functional Somatic Syndrome

“Functional somatic syndrome refers to several related syndromes that are characterized more by symptoms, suffering, and disability than by disease-specific, demonstrable abnormalities of structure or function.”
(Barsky, A. J. & Borus, J. F. , Ann Intern Med. 130, 1999)

For example, you continue to suffer from stomach pain and heartburn, so you get tested at a hospital, but the gastroscopy shows “no abnormalities”. However, the symptoms persist, and although they improve somewhat with medication, they soon return. You are told everywhere you go that there is “no abnormality” or it’s “just in your mind”.

This is the case where there are no organic abnormalities such as ulcers or gastritis, but there is a problem with the function (activity) of the stomach, causing symptoms similar to those of gastritis. For example, poor movement of the stomach causing a feeling of heaviness, or excessive secretion of gastric acid causing heartburn. This is called “functional dyspepsia”.

Core Diseases

Functional somatic syndrome is said to include the following “core diseases”.

  • Functional Dyspepsia
  • Irritable Bowel Syndrome
  • Fibromyalgia
  • Chronic Fatigue Syndrome

In gastroenterology, cardiology, dermatology, gynecology, and other fields, there are certain proportions of such diseases.
Of course, the specific symptoms and pathologies differ depending on the field, but there are common points in their characteristics and responses, such as large fluctuations due to stress and anxiety, and certain effects of antidepressants.

Examples of Functional Somatic Syndrome in Various Fields

Below are examples of functional somatic syndrome in various fields, as cited in the literature.

Functional somatic syndromes by speciality

  • Gastroenterology: Irritable bowel syndrome, functional dyspepsia
  • Gynaecology: Premenstrual syndrome, chronic pelvic pain
  • Rheumatology: Fibromyalgia
  • Cardiology: Atypical or non-cardiac chest pain
  • Respiratory: Hyperventilation syndrome
  • Infectious diseases: Chronic (postviral) fatigue syndrome
  • Neurology:Tension headache
  • Dentistry: Temporomandibular joint dysfunction, atypical facial pain
  • Ear, nose, and throat: Globus syndrome
  • Allergy: Multiple chemical sensitivity
(Wessely S, Nimnuan C, Sharpe M. Functional somatic syndromes: one or many? Lancet. 1999 Sep 11;354(9182):936-9.)

Characteristics and Issues of Functional Diseases

In these diseases, subjective (self-aware) symptoms often do not match objective (medical) assessments, causing various problems. For example, undergoing unnecessary medical examinations, miscommunication with medical personnel, and stress from not being understood by those around you.

Below are summarized the characteristics and issues.

  • Various secondary problems due to the “gap” between subjective bodily symptoms and disabilities and medical explanations, leading to chronicity and complexity of symptoms, confusion including surrounding systems, and a vicious cycle.
  • A pathological state is formed by the interaction of both physical factors (functional pathology) and psychological/social factors.
  • Although diagnostic names are given in various specialized areas, there are overlaps in symptoms and diagnostic criteria, and symptom migration, combining individual pathologies with common pathologies.
  • In physiological processes, abnormalities in autonomic nervous/thalamo-pituitary system functions, and stress response system functions are involved in the pathology.
  • Anxiety and depression are involved as psychological/social factors, but only partially.
    Other factors such as amplification of bodily sensations, lack of support from family and others, illness behavior, and stigma are involved.

Given such characteristics and issues, more appropriate understanding and responses to the pathology are required.
Therefore, we are examining psychosomatic evaluation and therapeutic methods for functional somatic syndrome and stress-related diseases from various angles.