Irritable bowel syndrome among Norwegian nurses – associations with insomnia, excessive sleepiness, shift work disorder and shift work schedule

BACKGROUND: The present study aims to investigate the prevalence of irritable bowel syndrome (IBS) among nurses, and its associations with sleep- and sleepiness problems and shift work, as both shift work and poor sleep have been linked to high prevalence of gastrointestinal symptoms and IBS. METHODS: The data stem from 1335 Norwegian experienced nurses participating in the cohort “SUrvey of Shift work, Sleep and Health” (SUSSH). Results are based on cross-sectional data collected in the 10th wave (2018) of SUSSH. The nurses responded to a questionnaire that assessed symptoms of IBS according to the Rome IV diagnostic criteria, symptoms of insomnia measured with the Bergen Insomnia Scale (BIS), excessive sleepiness measured with the Epworth Sleepiness Scale (ESS), shift work disorder (SWD) and shift work schedule such as day vs. night work, number of nights and number of quick returns (less than 11 h between two shifts) worked the last year. Chi-square tests were used to compare categorical variables and crude and adjusted (for sex and age) logistic regression analyses were conducted with IBS as dependent variable. RESULTS: A total of 6.3% of the nurses reported IBS, 30.9% insomnia, 25.6% excessive sleepiness and 33.6% shift work disorder, respectively. In total 59.8% were working daytime schedules, while 40.2% had a work schedule that included night work. IBS was more prevalent among nurses with insomnia (no/yes) (4.8% vs. 9.7%, p