The Bidirectional Relationship Between Sleep Disturbance and Functional Dyspepsia: A Systematic Review to Understand Mechanisms and Implications on Management

Abstract

Functional dyspepsia (FD) is a prevalent chronic digestive disorder that significantly impacts patients' quality of life. Sleep disturbance (SD) is common among FD patients, yet the relationship between SD and FD remains poorly characterized. This systematic review explores the bidirectional relationship between FD and SD, investigating underlying mechanisms and implications for management. A rigorous and comprehensive systematic search was conducted across PubMed, PubMed Central (PMC), Google Scholar, Cochrane Library, and ScienceDirect using select keywords related to SD and FD. Only studies published in English from the past 10 years that met inclusion and exclusion criteria were included. Quality assessment tools specific to study types were employed to minimize bias. After applying inclusion and exclusion criteria and quality assessments, the review encompassed 30 studies. The key findings reveal that FD is frequently associated with SD, with a significant proportion of FD patients reporting poor sleep quality. The mechanisms linking SD and FD are complex, involving the circadian rhythm, visceral hypersensitivity, immune responses, and psychological factors. Nonpharmacological treatments like cognitive behavioral therapy (CBT), acupuncture, and pharmacological neuromodulators have shown promise in managing FD and SD, offering hope for improved patient outcomes. SD and FD share a significant bidirectional relationship, influenced by a complex interplay of physiological, psychological, and lifestyle factors. Addressing SD in FD patients may improve overall symptom management. Further research is crucial, as it should focus on isolating specific SD causes and their direct impacts on FD and other functional gastrointestinal disorders (FGIDs), opening up new avenues for understanding and treatment.

Keywords: circadian; disturbance; dyspepsia; epigastric pain; functional; functional dyspepsia; indigestion; melatonin; post prandial fullness; sleep.

Figure 1. PRISMA 2020 flowchart of the databases and studies

PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analyses

Figure 2. Gut-brain axis and its bidirectional communication

Gut-brain interaction and bidirectional relationship of SD and FD. SD alters the circadian rhythm, affecting the release of neuromodulators and hormones such as melatonin, causing altered gut motility, visceral hypersensitivity, and immune dysregulation. Altered gut motility causing early satiety and abdominal discomfort is called PDS. Visceral hypersensitivity and immune dysregulation are associated with epigastric pain and are referred to as EPS. Sometimes with overlap (PDS-EPS). Symptoms of FD may cause waking or increased sleep latency, causing SD. Created with Biorender.com SD: sleep disturbance; FD: functional dyspepsia; PDS: postprandial distress syndrome; EPS: epigastric pain syndrome

Figure 3. Lifestyle factors associated with SD and FD

Common lifestyle factors affecting circadian rhythm and ultimately leading to SD. SD, in turn, has multiple effects on the gastrointestinal tract, which may cause or enhance symptoms of FD. Created with Biorender.com SD: sleep disturbance; FD: functional dyspepsia