[2][13] Specifically in children and adolescents, anxiety and depression may present as FGID-associated somatic complaints, such as nausea, vomiting, and abdominal pain.
[14] Similarly, anxiety in individuals with FGIDs is linked to greater pain severity, frequency, duration, chronicity, and disabling effects.
[15] This is because psychological stress can impact the gut's mucosal barrier functions, allowing bacteria and bacterial products to migrate and cause pain, diarrhea, and other GI symptoms.
Conversely, since the brain-gut axis is bidirectional, GI inflammation and injury can amplify pain signals to the brain and contribute to worsened mental status, including anxiety and depression symptoms.
Due to the nature of the disease, individuals with an FGID may have difficulty with regular school or work attendance and participation in extracurricular activities, leading to isolation and a lack of peer support.
As such, stressful situations which influence socialization (seen as either a lack thereof or negative experiences) may lead to an impaired functioning in patients with FGIDs.
[18][19] The physiology of FGID is characterized by abnormal motility, visceral hypersensitivity as well as dysregulation of the immune system and barrier function of the GI tract as well as inflammatory changes.
In addition, neurotransmitters send signals related to thoughts, feelings, and pain regulation from the brain to the GI tract.
The brain-gut axis influences the entire body through a variety of pathways; it regulates sensory, motor, endocrine, autonomic, immune, and inflammatory reactions.
Within the physical and psychological interactions of FGIDs specifically, psychiatric disorders such as anxiety, depression, and even autism are well-linked to GI dysfunction.
[29] Negative emotions such as fear, anxiety, anger, stress, and pain may delay gastric emptying, decrease intestinal and colonic transit time, and induce defecation and diarrhea.
[1] Because FGIDs are known to be multifactorial with external stressors and environmental factors playing a role in their development, current research demonstrates that psychological treatments may be effective in relieving some symptoms of the disease.
Interventions such as cognitive behavioral therapy (CBT), hypnotherapy, and biofeedback-assisted relaxation training (BART) each show promise in symptom reduction.
TCAs, specifically amitriptyline, show promising results when examining common FGIDs symptoms such as pain and poor quality of life.