The syndrome irritable bowel (IBS) is also called irritable bowel syndrome. In France, the term “functional colopathy ” is also used. It is a digestive disorder that is characterized by discomfort or painful sensations in the stomach.
These discomforts are associated with the change in the rate of passage of food in the colon, also called the large intestine (see diagram). Passing speeds that are too fast or, on the other hand, too slow will cause different symptoms. Thus, when the phases of contraction and relaxation of intestinal muscles are faster or stronger than normal, the colon does not have time to absorb the water contained in food. This causes diarrhea.
When contractions are slower and weaker than normal, the colon absorbs too many fluids, resulting in constipation. The stools are then hard and dry.
Generally, there are 3 subcategories of the syndrome according to the type of main symptoms.
- Syndrome with pain and diarrhea.
- Syndrome with pain and constipation.
- Syndrome with pain, diarrhea and constipation.
Who is affected?
The irritable bowel syndrome is a common disorder: it is the cause of 30% to 50% of visits to a gastroenterologist .
This syndrome affects 10% to 20% of the population of Western countries; it is mostly women. However, it should be noted that this is an estimate because it is difficult to obtain reliable statistics. On the one hand, it seems that only 15% of affected people consult their doctor about it. On the other hand, there are 2 different diagnostic grids (Manning and Rome III), which influence the number of people considered to be suffering from irritable bowel syndrome.
This disorder appears gradually in adolescents and young adults. In most cases, irritable bowel syndrome is chronic. However, those affected may experience longer or shorter periods of remission. Their discomfort can appear every day for 1 week or 1 month, then disappear, or even last a lifetime. Only a minority of patients have very uncomfortable symptoms.
Unlike more serious intestinal diseases, such as ulcerative colitis and Crohn’s disease, irritable bowel syndrome does not cause inflammation, does not alter the structure of the intestinal mucosa and does not increase risk of colorectal cancer. This is why irritable bowel syndrome is considered a functional disorder rather than a disease.
On the other hand, the pain, diarrhea and constipation it causes can become very bothersome.
The syndrome irritable bowel can also seriously hinder the professional and social activities of those who suffer, impoverish their quality of life and lead to anxiety and depression.
Finally, other disorders have been found to be associated with this syndrome, such as painful menstruation, chronic fatigue syndrome and fibromyalgia. For now, we do not know the reason.
When to consult?
If the discomfort is new, very bothersome or disturbing, it may be helpful to consult a doctor. Indeed, other health problems can give similar symptoms.
A medical consultation is necessary in case of blood in the stool, fever, significant weight loss or uncontrollable diarrhea, especially if it also occurs at night.
Causes of syndrome irritable bowel
The causes of this disorder are still unknown and are the subject of much research. Two basic hypotheses are proposed: either sufferers suffer from abnormal and painful contractions of the intestine, or they are more sensitive than normal to movements of the colon and rectum, usually imperceptible.
As women are more affected than men and their discomfort worsens during menstruation, some researchers believe that hormonal changes play a role.
According to some data, up to 25% of cases of irritable bowel syndrome occur after a gastrointestinal infection. The hypothesis of an imbalance of the intestinal flora is also explored.
In addition, some researchers believe that an abnormal level of serotonin in the digestive tract could be the cause of the syndrome. This could explain why many affected patients suffer from anxiety and depression. It should be noted that serotonin has a significant effect on mood and bowel movements.
It is also possible that there is a link between irritable bowel syndrome and sexual or physical abuse experienced during childhood.
It has been thought that stress is a cause of this disorder, but it is not. On the other hand, it generally increases the symptoms (especially the pain).