Sleep Disturbances, Fatigue and Immune Markers in the Irritable Bowel Syndrome and Inflammatory Bowel Disease, a Systematic Review.

Background: The irritable bowel syndrome (IBS) and inflammatory bowel diseases (IBD) are gastrointestinal (GI) diseases characterized by abdominal pain and altered bowel patterns. Fatigue and sleep disturbances are prevalent in these GI diseases, with a bidirectional relationship suggested between GI symptoms and sleep quality. If poor sleep results in increased GI symptoms, improving sleep quality may alleviate symptoms. However, if GI symptom burden independently drives poor sleep, alleviating symptoms by disease modification rather than targeting sleep should be the goal of management. Therefore, we aimed to determine if there is a relationship between gastrointestinal symptoms that influences sleep disturbances and/or fatigue.

Methods: A systematic literature search in five databases was conducted using PRISMA guidelines to identify studies addressing fatigue, sleep disturbances, and GI diseases until June 2025. Inclusion criteria were original articles with confirmed GI disease diagnosis and healthy control groups. Data extraction included participant demographics, assessment tools, inflammatory findings, medication use, and disease severity. Quality assessment utilized the Newcastle Ottawa Scale.

Key Results: Of 14,664 articles, 18 studies were included: 7 focused on IBS, 9 on IBD, and 2 on both IBS and IBD. Findings revealed increased fatigue and sleep disturbances in GI patients compared to controls, with IBS patients reporting more fatigue and sleep disturbances than IBD. GI disease severity was strongly associated with sleep quality and fatigue levels.

Conclusions & Inferences: This systematic review highlights the strong association between fatigue and sleep disturbances and GI diseases, which are further exacerbated by disease severity.