What is chronic functional abdominal (CFAP) pain?
Chronic abdominal pain is persistent pain of the abdomen. It is thought to occur because of altered sensitivity to nerve impulses in the gut and brain or is pain that remains long after an initial process (e.g. surgery or disease) has resolved. It is not associated with any altered function of the intestinal system.
What causes chronic functional abdominal pain?
Nerve impulses are carried from the abdomen to the spinal cord and then to the brain. There are many connected regions of the brain responsible for the sensation of abdominal pain. One of these regions is responsible for the location and intensity of abdominal pain while another connected region is concerned with emotions and memory. Because of this connection, pain perception can be influenced by a person’s emotions or life experiences.
While the symptoms of CFAP may occur without any apparent cause they can occur following a traumatic life event such as a divorce, death of a loved one or a history of physical or sexual abuse. People may find that the symptoms become worse during stressful periods in their life.
Repeated injury to the abdomen such as multiple abdominal surgeries or infection can cause the abdominal nerve receptors to become overly sensitive. This means that a later painful incident is perceived as more painful than before. Even normal abdominal activity can cause pain. This is called ‘visceral hypersensitivity’ which means that there is increased sensitivity of the intestines.
Symptoms of chronic functional abdominal pain
- continuous or nearly continuous abdominal pain that lasts for six months or longer
- no relationship between pain and intestinal function
Diagnosis of chronic functional abdominal pain
CFAP is a difficult condition to diagnose. Firstly, the doctor will take a full detailed history and perform a physical examination to rule out other chronic abdominal issues such as Irritable Bowel Syndrome (a long-term disorder affecting the digestive system) or chronic dyspepsia (chronic or recurrent pain in the upper abdomen). They may order tests to discount any other conditions. However, CFAP is usually diagnosed based on the fact that it is not related to gut function unlike IBS which causes a change in bowel function or dyspepsia which causes pain after eating.
What causes chronic functional abdominal pain?
It is not usually possible to totally eliminate the symptoms of CFAP. The aim of treatment is to try and help people gain control over their symptoms and improve daily function.
It is often useful to keep a diary to record the abdominal pain and possible events or emotions which generate symptom flare-ups. This information can be used by a person and their doctor to gain a better understanding of what exacerbates (makes worse) their symptoms in order to develop appropriate strategies to better control them.
Psychological treatments may also be helpful especially for people whose symptoms are generated by periods of stress, anxiety or depression (particularly after a traumatic life event). Therapies can include relaxation techniques, imagery and hypnosis. Pain management programmes and cognitive behavioural therapy (CBT) can also be effective.
Medication can also be used in the treatment of chronic functional abdominal pain. An antidepressant may be prescribed with severe pain as this has been shown to help with the pain (it is usually given in a lower dose than when taken for depression). A tricyclic antidepressant drug such as Amitriptyline may partly help with the pain of CFAP and assist with sleep. This medication may cause side effects such as a dry mouth, drowsiness, constipation or nausea. It is usually started at a low dose and increased slowly so that side effects can be minimised. Another type of antidepressant that might be used is a selective serotonin reuptake inhibitor (SSRI). They may cause side effects such as agitation, sleep disturbances, vivid dreams and diarrhoea.
Opioid type drugs such as morphine and oxycodone are not recommended for the treatment of this condition and may prove harmful if taken over a long period of time. Taking opioids for CFAP may cause a condition known as Narcotic Bowel Syndrome.
It is important that people with CFAP work with their doctor to gain the best outcome for controlling the symptoms of the condition by utilising the strategies that are the most helpful in relieving the pain of chronic functional abdominal pain.
Chronic Pain Australia offers support and advice to people and their families with persistent pain (chronicpainaustralia.org.au).
