10 Facts About Irritable Bowel Syndrome (IBS)

Irritable bowel syndrome (IBS) is a widely known bowel condition but there is still widespread misconceptions about the condition. All too often people label chronic bowel diseases as irritable bowel syndrome without fully understanding the extent of the syndrome. However, the symptoms of IBS may be seen with a host of other bowel diseases, some of which may have life-threatening consequences if left untreated. It is therefore important to know the basic facts about IBS and clear up the confusion and misconceptions between IBS and other chronic bowel conditions like inflammatory bowel disease (IBD).

IBS is not a disease

More correctly, irritable bowel syndrome does not occur due to any pathology. This simply means that there is no specific disease process that can be identified in the bowel and usually there are no severe consequences with progression of the condition. Why IBS arises and what exactly is “wrong” with the body for IBS to be present is unknown. Irritable bowel syndrome is therefore said to be a functional bowel disorder meaning that there is an abnormality in the bowel function but it is not a pathological process.

IBS has many names

Irritable bowel syndrome or IBS for short is the accepted name for the collection of symptoms that characterizes the condition. However, it is also known by several other names. The still widely used spastic colon is one such name which has been deemed outdated. It is also known as irritable colon but this may be inaccurate in that the disturbance may not lie solely in the colon. Another name for IBS is nervous colon as the condition seems to be aggravated by stress and is more likely due to over- or underactivity of the nerves controlling the lower bowel.

Constipation or diarrhea

Irritable bowel syndrome is often portrayed in popular media as a diarrheal condition entirely. However, this is untrue. Constipation can be the predominant symptom of IBS in some cases, just as much as diarrhea is the hallmark in other instances. At times there is an alternation of constipation and diarrhea. The fact is that the bowel habit is altered in IBS but this can be at either end of the spectrum. Part of the criteria related to the diagnosis as outlined by the Rome III criteria for IBS diagnosis states that two or more of the following should be present :

  • Frequency of stool is altered.
  • Form of stool is altered.
  • The passage of stool is abnormal with straining or an urging to defecate.
  • Mucus in the stools.
  • Abdominal bloating or the patient reports distention of the abdomen.

Four different types of IBS

Given the difference in bowel habit that can be the predominant feature of IBS at certain times, the condition can be classified into four different types.

  • Diarrhea-predominant irritable bowel syndrome (IBS-D) where diarrhea is the main alteration in bowel habit.
  • Constipation-predominant irritable bowel syndrome (IBS-C) where the patient mainly suffers with constipation.
  • Combination of diarrhea and constipation known as mixed irritable bowel syndrome (IBS-M).
  • Alternating diarrhea and constipation in irritable bowel syndrome (IBS-A).

Foods trigger but do not cause IBS

Most IBS patients will complain of foods that trigger attacks or exacerbate the symptoms of irritable bowel syndrome. It is important to note that food does not cause the condition although certain food intolerances, like gluten intolerance, have been associated with IBS in some studies. Food is so much of a factor in IBS that dietary measures are considered as part of the treatment approach. However, there are no specific foods that can be isolated. Sensitivity to different foods are high individualistic, varying from one IBS patient to another. Instead patients should identify and avoid specific foods that exacerbate their IBS. A high fiber diet and abstaining from gluten and coffee may be a starting point.

Stress, smoking and alcohol

Certain factors are known to exacerbate IBS in the majority of patients. The worst offenders appear to be psychological stress, alcohol consumption and cigarette smoking. However, not every patient associates these factors with the severity of their IBS. It is only when these factors are removed and with the subsequent improvement of IBS that it correlation with the condition is identified. Therefore IBS patients need to consider stress management, smoking cessation and moderation in alcohol use as part of the management of the condition.

IBS comes and goes

Most patients with IBS report periods where the symptoms resolve completely. These remission periods can last for weeks or months and in rare cases, even for years. However, the symptoms tend to recur in time. Similarly patients may have periods where the symptoms exacerbate to the extent that it severely affects the quality of life. These attacks are usually short-lived and prompt patients to seek medical attention. Between periods of remission and acute attacks, symptoms are present but usually mild and tolerable.

IBS is common

It is estimated that IBS affects as much as 10% to 20% of the population. This means that between 1 in 5 to 1 in 10 people suffer with some degree of irritable bowel syndrome. It makes IBS one of the most common bowel disorders. However, the exact prevalence is difficult to estimate as most IBS patients do not seek medical care. In fact it is believed that only about 10% to 20% of the IBS patients (not the general population) seek medical care for their condition. In Western nations, women are 2 to 3 times more likely to suffer with IBS and over half of all patients report symptoms starting before 35 years of age.

IBS link to bowel cancer

Irritable bowel syndrome is not associated with bowel cancer. However, the symptoms of IBS and bowel cancer are very similar and there are cases of bowel cancer being misdiagnosed as IBS at the outset. Inflammatory bowel disease (IBD) is another bowel condition that is sometimes confused with IBS. There is a link between inflammatory bowel disease (IBD) and bowel cancer, particularly colorectal cancer. Although IBS patients are not at a greater risk of developing bowel cancer, regular screening is nevertheless advisable as often other conditions are misdiagnosed as IBS.

Criteria for IBS diagnosis

IBS is a functional bowel disorder where that is not associated with any disease process. A diagnosis of IBS is therefore reached by excluding other possible bowel conditions that may present with similar symptoms. This requires a different investigations such as a colonoscopy. The lack of pathology thereby excluding a host of bowel diseases with symptoms similar to IBS is not sufficient for diagnosing irritable bowel syndrome. The Rome III criteria states that IBS can be diagnosed if a patient has abdominal pain or discomfort for at least 3 days per month for the past 3 months that is associated with 2 or more of the following characteristics :

  • Abdominal pain that is relieved with defecation.
  • Abdominal pain associated with a change in stool frequency.
  • Abdominal pain associated with changes in stool form or appearance.

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