Inflammatory bowel disease versus irritable bowel syndrome:: a hospital-based, case-control study of disease impact on quality of life

Background: Inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) are intestinal diseases perceived differently by patients and doctors: the former is considered essentially as an 'organic' disease (i.e. an illness in which the role of stress or psychological factors is at best secondary to the disease itself), whereas the latter is acknowledged as a 'functional' disorder (i.e. illness thought to be more in the 'mind' than in the body of the patient). Accordingly, the respective impact of the two diseases on patients' health-related quality of life (HRQOL) is perceived to be very different. We aimed to compare the relative impact of the disease on HRQOL, psychological profile and perceived burden of stressful life events in two groups of outpatients suffering from IBS and IBD and attending our outpatient department at an Italian university hospital. Eighty patients with IBD ( 26 with ulcerative colitis and 54 with Crohn disease) and 85 controls with IBS formed the patient samples of the study. Methods: Three questionnaires were given to the patients while they were attending the outpatient department because of their previously diagnosed disease, namely the SF-36 ( a generic well-validated tool for measuring HRQOL), the SCL-90 ( for assessing the psychological profile of patients), and the Holmes & Rahe schedule ( for the assessment of stressful life experiences). The results were then compared by means of analysis of variance ( ANOVA) and Bonferroni-adjusted t test, when appropriate. Results: HRQOL appeared to be similarly reduced in both disease groups (SF-36 overall mean value: 58.2 +/- 16.1 in IBS patients versus 56.4 +/- 22.3 in IBD patients; P > 0.05) in comparison with normative Italian data. Furthermore, the overall severity of psychological symptoms was not statistically different between patients suffering from IBD versus IBS, as shown by SCL-90 mean scores of 0.89 +/- 0.45 versus 0.83 +/- 0.48, respectively ( P > 0.05). On the contrary, the severity of recent stressful life experiences was perceived to be higher by IBS than by IBD patients (mean SRE score: 110.8 +/- 110.2 versus 61.6 +/- 78.8; P < 0.05). Conclusion: Our study supports the notion that, at least in referral centres, patients with IBS show health-related quality of life, psychological distress and recent occurrence of stressful life events of severity at least comparable with age-matched IBD patients.