While it has been considered common knowledge that stress affects irritable bowel syndrome, scientific data in patients has been lacking until recently. At the MBDC, Drs. Mary-Joan and Charles Gerson have recently found a correlation between perception of stress — how overwhelmed versus how much in control patients felt — and their level of symptoms.

Many years ago, it was noted that the lining of the rectum can become reddened and swollen if a person is placed under acute mental stress. We now know that stress causes the brain to release hormones and activate nerve pathways. The end result of this process is the release of chemicals called neurotransmitters in the lining of the colon that can alter colonic motility and sensitivity to pain.

The following research article summaries deal with IBS and stress.

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A Study of Stress and IBS: Level of Chronic Life Stress Predicts Clinical Outcome in IBS

Introduction & Methods

• This study examined the relationship between chronic life stress and the clinical course of IBS. A group of IBS patients were followed for 16 months.

Results

• 41% of patients improved significantly during their clinical course. None of these improved patients had suffered a significant chronic stressor, defined as divorce, relationship difficulties, serious illness (of self or others), lawsuits, business failures, housing difficulties and caring for a family member with significant physical and/or emotional problems.
• Presence of at least one threatening chronic difficulty during the first 6 months highly predicted symptom intensity even after a time lag of 10 or more months.

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Effects of Stressful Life Events on Bowel Symptoms: Subjects with Irritable Bowel Syndrome Compared to Subjects without Bowel Dysfunction

Introduction & Methods

• A group of IBS patients were followed over the course of a year, during which they filled out a stress questionnaire and a bowel symptom scale at three month intervals. A record of medical visits and days absent from work was also gathered. These patients were accessed through a community questionnaire, not through doctors' offices, so they represent people not necessarily seeking medical care.

Results

• IBS patients reported significantly more stress than non-IBS individuals.
• There was a significant correlation between stress and GI symptoms for individuals with and without IBS. However, the IBS patients were more affected by stress, as they experienced more severe symptoms.
• There were also significant correlations between sick days and physician visits and levels of stress. Stress is clearly not the only determinant of IBS symptoms, but statistical evaluation showed that stress accounted for 11% of all contributing factors.

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The Relationship between Daily Stress and Symptoms of Irritable Bowel: A Time-Series Approach

Introduction & Methods

• This study investigated the link between every day stress, or “hassles,” and GI symptoms in IBS patients. Specifically, it was determined whether IBS symptoms were related to stress during the preceding days, the day that stress occurred, or the days following a particularly stressful day.

Results

• For over half the patients, there was a temporal relationship between stress and symptoms. Symptoms were found to be most severe two days before hassles and on the day of the stress itself.

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The Relationship between Daily Life Stress and GI Symptoms in Women with IBS

Introduction & Methods

• This study examined the relationship between daily stress and GI symptoms in women. Three groups of women were studied: (1) patients with IBS that caused them to visit a physician, (2) patients with IBS who did not seek medical help, and (3) a control group.
• Daily health diaries that monitored symptoms and stress were filled out over two menstrual cycles.

Results

• There was a significant relationship between daily stress and daily symptoms for both IBS groups, but not in the control group.
  Stress levels were higher in both IBS groups than controls.
• Whether the women were pre-menstrual or menstruating did not affect the results.
• In some IBS patients, symptoms worsen months after a stressful situation has occurred. In others, the time relationship may be a matter of days or even on the same day.

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The Role of Stress in Symptom Exacerbation among IBS Patients

Introduction & Methods

• Researchers conducted a study to determine the inter-relationship between past and present stress and the occurrence and severity of IBS symptoms.
• IBS patients and control participants completed a survey measuring self-reported stress within the past 12 months. IBS patients also received psychiatric evaluations.
• In a 4 week diary, IBS patients rated the severity of eight GI symptoms (abdominal pain, abdominal tenderness, diarrhea, constipation, bloating, flatulence, belching, and nausea). Additionally, they completed a survey to evaluate the daily occurrence and impact of various potentially stressful events.

Results

• Stress and symptoms tended to occur at the same time; one did not appear to cause the other.
• Stress and symptoms appear to have a circular effect on each other. The best predictor of future stress is current stress, and the best predictor of future symptoms is current symptoms. Thus, stress reduction may not be as effective in the treatment of future IBS symptoms as a treatment aimed at reducing stress with more direct attention to reduction of symptoms themselves.

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