High prevalence of irritable bowel syndrome-type symptoms in microscopic colitis: implications for treatment.

Background: Patients with microscopic colitis (MC) often present with abdominal pain and diarrhoea, and previous data suggest that there may be overlap between MC and irritable bowel syndrome (IBS). We evaluated the prevalence of IBS-type symptoms in patients with MC, and assess the impact of these symptoms on psychological health and quality of life.

Methods: We conducted a cross-sectional survey of individuals with a histological diagnosis of MC, collecting demographic data, Rome III IBS-type symptoms, and mood, somatization, and quality of life data.

Results: In total, 151 (31.6%) of 478 individuals with a new diagnosis of MC completed questionnaires, 52 (34.4%) of whom reported IBS-type symptoms. The commonest histological subtype was collagenous colitis (51.7%, n = 78), followed by lymphocytic colitis (39.1%, n = 59). Individuals with IBS-type symptoms had significantly higher levels of anxiety [Hospital Anxiety and Depression Scale (HADS) anxiety score 8.6 versus 5.1, p < 0.001], depression (HADS depression score 6.2 versus 3.6, p = 0.001), and somatoform-type behaviour (Patient Health Questionnaire 15 score 12.7 versus 8.0, p < 0.001) compared with individuals who did not. Those with IBS-type symptoms scored significantly worse across all domains of the 36-item Short Form questionnaire, except for physical functioning.

Conclusions: More than one third of individuals with MC reported IBS-type symptoms, although whether this is due to ongoing inflammation is unclear. These individuals had higher levels of anxiety, depression, and somatization, and impaired quality of life. Identifying concomitant IBS in individuals with MC may have important implications for management decisions.