Definition
- IBS is defined as abdominal discomfort or pain associated with altered bowel habits for at least three days per month in the previous three months, with the absence of organic disease.
Irritable Bowel Syndrome
- First described in 1771.
- 50% of patients present <35 years old.
- 70% of sufferers are symptom-free after 5 years.
- Family physician (FPs) will diagnose one new case per week.
- FPs will see 4-5 patients a week with IBS.
- Point prevalence of 40-50 patients per 2000 patients.
What Is IBS?
- A syndrome.
- One man’s constipation is another man’s diarrhoea.
- Cause unknown.
- 20% seem to start after an episode of gastroenteritis.
Epidemiology
- IBS: chronic, relapsing and often life-long disorder.
- Characterized by the presence of abdominal pain or discomfort.
- People with IBS present to primary care with a wide range of symptoms.
- Usually between 20 and 30 years of age.
- Twice as common in women as in men.
- IBS diagnosis should be a consideration when an older person presents with unexplained abdominal symptoms.
Causes
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The exact cause of IBS is not known.
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Faulty communication between the brain and the intestinal tract is one cause of symptoms.
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Miscommunication causes abnormal muscle contractions or spasms, which often cause cramping pain.
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Many people who have IBS seem to have unusually sensitive intestines.
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It isn’t known why their intestines are more likely to react strongly to the elements that contribute to IBS.
Contributing Factors:
- Eating (though no particular foods).
- Stress and psychological issues, such as anxiety and depression.
- Hormonal changes, such as during the menstrual cycle.
- Some medicines, such as antibiotics.
- Infection of the digestive tract, such as salmonella.
- Genetics: IBS may be more likely to occur in people who have a family history of the disorder.
Pathophysiology
- Gastrointestinal motility
- Visceral hypersensitivity
- Intestinal inflammation
- Post-infectious
- Bacterial overgrowth
- Food sensitivity