Irritable bowel syndrome (IBS) symptoms have been linked to high rates of anxiety and depression. Due to the high rates of anxiety and depression among IBS patients it sparked researchers to believe there may be a casual relationship between psychological factors and IBS symptoms.
A study presented at the 22nd United European Gastroenterology Week (UEG Week 2014) in Vienna, Austria found that depression contributes to the pain processing experienced in IBS. Professor Sigrid Elsenbruch said, “Our study has shown that patients with IBS are less able to suppress pain signals in the brain coming from the bowel and that depression plays a role herein. This study confirms the complex relationship between the gut and the brain and shows that affective disorders may contribute to the development or maintenance of disturbed pain processing in IBS.”
IBS is characterized by abdominal pain, severe bloating, and altered bowel habits and it has been observed that depression and anxiety commonly co-exist alongside IBS. Prof. Elsenbruch added, “The fact that so many people with IBS have anxiety and depression has led many to speculate that IBS is primarily a psychological, not a physical, disorder. However, the condition is complex and most likely results from an interplay between psychological and biological factors. In fact, we don’t really know whether anxiety and depression result from having IBS or whether they contribute to the development or maintenance of symptoms. In many patients, both possibilities may be true at the same time.”
Neuroimaging has revealed that in patients with IBS they possess a lower pain threshold. In Prof. Elsenbruch’s study, she performed pressure-controlled barostat system in 17 IBS patients’ ad 17 control persons. MRI scans were used to assess pain-related brain areas while the patients received a placebo intravenous but were told was an anti-spasmolytic drug. This was in order to observe activation patterns during a placebo response.
In healthy individuals there was a reduction in neural activation in pain-related areas of the brain during the placebo and saline treatment. The same was not found in IBS patients revealing a deficiency in central pain inhibitory mechanisms in IBS. Furthermore, researchers found that those with higher depression scores on the Hospital Anxiety and Depression Scale (HADS) were also associated with lower central pain inhibition.
Prof. Elsenbruh concluded, “Our findings suggest that patients with IBS do not process visceral pain signals in the same way as healthy people and are unable to suppress pain signals in the brain and, as a result, experience more pain from the same stimuli. The fact that the presence of depression was associated with altered brain responses suggests that depression may contribute to these abnormal pain processes in IBS patients.”
In an alternative study researchers found using psychological therapy to treat symptoms of IBS may be beneficial. Additionally, the effects of psychological therapy were found to last six to 12 weeks after the therapy was completed.
Senior author Lynn S. Walker said, “Our study is the first one that has looked at long-term effects. We found that the moderate benefit that psychological therapies confer in the short term continue over the long term. This is significant because IBS is a chronic, intermittent condition for which there is no good medical treatment.”
Researchers reviewed numerous studies which explored different forms of psychological therapy and found that not one therapy was more successful than the other but rather they all offered similar levels of success.
First author Kelsey Laird concluded, “In this study we looked at the effect of psychological therapies on gastrointestinal symptoms. In a follow-up study I am investigating the effect that they have on patients’ ability to function: go to work, go to school, participate in social activities and so on.”
The findings were published in Clinical Gastroenterology and Hepatology.