Many researchers have published different studies regarding treatment of irritable bowel syndrome (IBS) symptoms with antidepressant medications and psychological therapies, with varying degrees of success. To evaluate if there were common themes, a panel of researchers at McMaster University Medical Centre analyzed and tallied 32 of these published studies in a meta-analysis.
IBS is a common debilitating functional gastrointestinal disorder, affecting as many as 20% of Canadians. The symptoms include abdominal pain, bloating, constipation, and/or diarrhea. A significant number of IBS patients also report higher levels of depression, anxiety, or neuroticism than the general population. Many also report a low quality of life.
Although physicians prescribe antidepressant medications often to treat conditions of the central nervous system, which controls the brain and spinal cord, researchers recognize their role in treating a similar system, the enteric nervous system. As part of the autonomic nervous system, the enteric nervous system is responsible for regulating the movement of food through the gastrointestinal tract and for secreting the enzymes required for digestion. Since antidepressant medications modify pain perception, physicians have found these drugs helpful in treating patients who have other types of chronic pain and use them to help IBS patients suffering from abdominal pain.
The researchers also evaluated three psychological therapies:
Cognitive behavioural therapy (CBT) focuses on using your own thoughts and behaviour to help you through a situation, rather than focusing on changing the circumstances that are usually beyond your control. Patients who undergo CBT learn a new skill set to help manage their symptoms, which may help avert the need for medications. CBT is not a type of therapy that you can show up for once a week, as the success of CBT depends on how much the patient is willing to practice the skills they have learned in their day-to-day life, and to continue this thought process throughout the duration of the illness.
Hypnotherapy is a treatment wherein a therapist suggests new patterns of thinking and new physical responses to a patient who is undergoing hypnosis.
Relaxation therapy helps the patient focus on breathing and muscle relaxation.
The results, published in the journal, Gut, were quite promising. Antidepressants, such as selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs) were significantly better than the placebo at preventing IBS symptoms. In addition, psychological therapies were more effective than control therapy or a physician’s usual management routine. The studies show that for every four patients treated with antidepressants or a specific psychological therapy, one patient’s symptoms ceased.
The type or brand of antidepressant used did not affect the outcome, as all seemed to reduce abdominal pain effectively. However, there were more inconsistencies with psychological therapies. Cognitive behavioural therapy appeared to work the best. Although hypnotherapy provided some relief, relaxation therapy did not offer any symptom relief.