Objectives: To study the intensity and variation of pain and its temporal relation to eating and defaecation. Furthermore, what irritable bowel (IBS) patients mean by constipation and diarrhea and how bowel symptoms vary.
Design: Prospective daily symptom recording over 6 weeks.
Setting: The primary catchment area of University Hospital of Linköping.
Participants: Eighty consecutive patients fulfilling the Rome criteria; 63 finished the study.
Results: Fifty-nine of 63 patients recorded an average of 29 pain periods and 24 days with pain during the 6 weeks. Over-all pain burden decreased slightly over the study period. At inclusion 38 (64%) patients claimed that pain was relieved by defaecation. However, on average, only 10% of each patient's recorded pain periods were relieved by defaecation. At inclusion 29 (49%) patients claimed postprandial worsening of pain. On average, 50% of each patient's recorded pain periods worsened postprandially. The patients defined constipation as hard stools and diarrhea as loose stools and urgency. Stool frequency did not differ. Bowel symptoms varied within, but not between, fortnightly periods.
Conclusions: Postprandial worsening of pain should be included as a criterion in the clinical definition of IBS while the criterion 'pain relieved by defaecation' should be re-evaluated. IBS patients can probably be divided into subgroups based on stool consistency, not frequency. Daily records are superior to structured clinical interviews or questionnaires for a detailed study of symptoms in IBS.