Self-reported sleep impairment in functional dyspepsia and irritable bowel syndrome

Background/Aims Sleep impairment is a common complaint among patients with irritable bowel syndrome (IBS) and functional dyspepsia (FD). This study aimed to evaluate the prevalence of sleep impairment in FD or IBS patients, and to determine whether IBS-FD overlap induced more sleep disturbance than FD or IBS alone. Methods A population-based cohort in South Korea including 2251 subjects was asked about gastrointestinal symptoms including IBS and dyspepsia-related symptoms. In addition, sleep disturbance was measured using the Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale questionnaires. One-way ANOVA and logistic regression were used to assess differences among the 4 groups (healthy subjects, IBS alone, FD alone, and IBS-FD overlap). Results Of 2251 subjects who were surveyed by questionnaire, 2031 responded (92.5% response rate) and were analyzed. The prevalence of IBS, FD, and IBS-FD overlap was 8.0% (95% confidence interval [CI], 6.8-9.2%), 4.8% (95% CI, 3.9-5.8%), and 1.8% (95% CI, 1.2-2.4%), respectively. FD alone, but not IBS alone, was significantly associated with a poorer sleep quality index (OR, 2.68; 95% CI, 1.43-5.01) and more daytime sleepiness (OR, 2.21; 95% CI, 1.14-4.30), compared to healthy subjects. IBS-FD overlap had the greatest likelihood of a poorer sleep quality index (OR, 3.88; 95% CI, 1.83-8.19), daytime sleepiness (OR, 2.47; 95% CI, 1.01-5.67), and insomnia (OR, 2.84; 95% CI, 1.39-5.82), compared to healthy subjects. Conclusion A correlation between functional gastrointestinal disorders and sleep disturbance was demonstrated, which was significantly pronounced in the context of IBS-FD overlap.