To Örebro University

Introduction: In the general population, many people are affected by both insomnia and irritable bowel syndrome (IBS). In this study, we aimed to explore the prevalence of insomnia in patients with IBS and its association with the severity of gastrointestinal and extra-intestinal symptoms.

Methods: Patients with IBS according to Rome IV criteria, referred to the Physiology Unit of Rouen University Hospital (France) between September 2022 and February 2025, who completed various validated questionnaires during their visit to assess insomnia (Insomnia Severity Index (ISI)), IBS severity (IBS-SSS), anxiety and depressive symptoms (HAD-S), quality of life (IBS-QOL), upper gastrointestinal symptom severity (PAGI-SYM), and somatic symptom severity (PHQ-15), were prospectively included in our study. Patients were considered insomniacs when their ISI score was >= 15.

Results: Among 700 patients with IBS included in our analysis, 270 (38.6%) were insomniac. The presence of insomnia was associated with more severe gastrointestinal symptoms (IBS severity, IBS-SSS, p < 0.001) and somatic symptom severity (PHQ-15, p < 0.001). The hierarchical linear regression analysis showed that the ISI score was associated with higher scores of anxiety and depressive symptoms, the presence of functional dyspepsia and fibromyalgia, and, to a lesser extent, older age and higher IBS severity scores (Adjusted R-2 = 0.265).

Discussion: Our findings suggest that in patients with IBS, insomnia is linked with psychological and somatic symptom burden, and the presence of comorbidities such as functional dyspepsia, but causality cannot be inferred. Future studies using objective sleep assessments, such as polysomnography, are needed to confirm these associations.