FGID symptoms and definition
Main features of FGID
Physiological aspects of FGID
Physiological aspects of FGID
Clinical evaluation of FGID
Integrated management of FGID
References
References

Functional gastrointestinal disorders (FGIDs) are common disorders associated with persistent and recurrent gastrointestinal (GI) symptoms.¹ Several studies have shown that stress and psychological difficulties worsen FGID. This article focuses on the physiological and psychological aspects of FGID.

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FGID symptoms and definition

FGID is caused by abnormal functioning of the gastrointestinal tract. Recent studies have shown that approximately 40% of the world’s population is affected by her FGID.² Compared to men, women are more commonly affected by FGID. Symptoms usually decrease with age.

Some digestive system-related symptoms such as dysphagia, bloating, and abdominal distention Abdominal pain, constipation, indigestion, and diarrhea are classified as FGIDs.³ FGID was previously defined as an essentially unfounded condition, but this definition has evolved as our understanding of the issue has improved. According to the current definition, changes in brain-gut communication may be the main mechanism behind the expression of FGID.^Four

The Rome Foundation was founded in the late 1980s, when little information about the pathophysiology of FGID was available. The foundation has played an important role in conducting research and disseminating knowledge about these diseases. FGID’s current ROME IV classification system classifies 33 adult and 20 childhood disorders.^Five

Irritable bowel syndrome (IBS) has been found to be the most common form of FGID, followed by functional dyspepsia (FD). IBS causes abdominal discomfort, bloating, and changes in bowel habits, while FD causes epigastric pain and discomfort.

Main features of FGID

The three main features of FGID are motor, sensory, and cerebral-intestinal dysfunction. Motility is related to muscle activity in the gastrointestinal tract, which is essentially a hollow muscular tube. The normal movement of the gastrointestinal tract is peristalsis, which is a regular series of muscle contractions that start at the top and end at the bottom. Abnormal gastrointestinal motility is present in patients with FGID. Spasms of the muscles of the gastrointestinal tract can be very fast, slow, or disorganized and cause pain.

Sensation is determined by how the digestive tract responds to stimuli, such as digesting food. In some cases, the nerves leading to the gastrointestinal tract are so sensitive that even normal muscle contractions can cause significant discomfort and pain. Brain-gut axis disharmony greatly affects communication between the brain and the digestive system. The regulatory functions that maintain the brain-gut axis were found to be impaired in FGID patients.⁶

Physiological aspects of FGID

Several abnormal physiological features have been identified in people diagnosed with FGID, including low-grade immune infiltrates, altered gastrointestinal motility, dysbiosis, and increased intestinal permeability. Additionally, FGID patients showed visceral hypersensitivity and altered central nervous system (CNS) sensory input processing.⁷

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Gastroparesis is a movement disorder caused by delayed gastric emptying. Common symptoms associated with this condition include vomiting and nausea. Gastroparesis is thought to be associated with abnormal morphology of enteric nerve cells. Patients with IBS and FD have inflammatory cells in the lamina propria of the intestine and impaired motility.

Physiological aspects of FGID

Some symptoms of anxiety are similar to FGID, including nausea, abdominal pain, vomiting, and diarrhea. Gastrointestinal-specific anxiety is assessed using the Visceral Sensitivity Index (VSI), which helps predict the severity of IBS symptoms. Low mood and depression significantly contribute to gastrointestinal symptoms.⁸

Although FGIDs are not directly related to eating disorders, the consumption of certain foods associated with gastrointestinal symptoms can lead to eating disorders. In some cases, food phobias can occur due to a conditional combination of certain foods/meals and unpleasant gastrointestinal symptoms.

Clinical evaluation of FGID

Diagnosis of FGID usually involves a comprehensive approach in which the patient’s detailed medical history is considered, including weight loss, anemia, nocturnal symptoms, family history of cancer, and gastrointestinal bleeding. Clinicians will ask questions about your diet, psychological state, and lifestyle. All this information will be used to develop the patient’s FGID management plan.

A physical exam, including a rectal exam, is performed to determine the condition and function of the hemorrhoids and anus. Anal hypotonia can cause constipation. Patients with symptoms of IBS undergo blood and stool tests to determine if they have the condition. Helicobacter pylori, C-reactive protein, urea, electrolytes, and other biological markers. These patients also undergo endoscopy and abdominal ultrasound to confirm the presence of abnormalities.⁹

Integrated management of FGID

The heterogeneity of FGID makes it difficult to design a treatment that fits all patients. A biopsychosocial approach is designed to help clinicians identify the factors that cause symptoms. Altering these trigger points may reduce symptoms of the disease.

Once FGID is diagnosed, biopsychosocial factors are addressed to cure the condition. Appropriate lifestyle changes such as healthy eating, exercise, sleep, and limiting caffeine and alcohol intake can reduce multiple FGID symptoms. In addition to lifestyle changes, psychological factors such as stress, low mood, anxiety, and eating disorders should be evaluated and corrected.many drugs and Psychotherapy has been shown to be effective in treating FGID.^Ten

A recent meta-analysis confirmed that psychotherapies such as gut-directed hypnotherapy, cognitive behavioral therapy (CBT), relaxation and mindfulness therapy, and dynamic psychotherapy are effective for FGID. Of all psychotherapies, CBT is the simplest therapy to show significant reduction in his FGID symptoms. It should be noted that the success of psychotherapy depends on the expertise of the therapist. Interestingly, the use of antidepressants has also been shown to be effective in treating her IBS. However, most antidepressants have gastrointestinal side effects, such as constipation and diarrhea.

Biological management of FGID involves treatment of symptoms or underlying pathophysiology. Symptomatic treatment includes antiemetics for nausea and laxatives for constipation. The use of opiates to relieve pain should be avoided as it can lead to the development of narcotic bowel syndrome, which causes nausea, bloating, and constipation.

Antispasmodics are used to treat colicky abdominal pain in IBS. These drugs cause anticholinergic side effects such as constipation and dry eyes. To reduce the symptoms of FGID, it is important to choose medications or antidepressants wisely, taking side effects into account.