Night Work, Sleep Duration and the Immune System

ABSTRACT

Introduction/Objectives: Evidence suggests that night work, short sleep duration and sleep problems are associated with poor long-term health outcomes, including increased risk of infections. In this symposium, epidemiological data from recent studies among (a) patients in general practice in Norway and (b) day and shift/night workers participating in a large international study (ICOSS-2) on COVID-19 and longcovid, will be presented. Method(s) The study in general practice included a total of 1848 unselective patients visiting their general practitioner. The patients completed a one-page questionnaire while waiting for the consultation. The international study included a total of 7182 day and shift workers from 15 different countries around the world. These participants completed an online survey covering several aspects of sleep. Result(s) The study from general practice showed that patients reporting a sleep duration of less than 6 h had significantly higher risk of infection (any type) compared to patients reporting 7-8 h of sleep (Relative Risk (RR) 1.27, confidence interval (CI) 1.11-1.46). Furthermore, the risk of infection was significantly higher in patients with chronic insomnia compared to patients without insomnia (RR 1.15, CI 1.05-1.27). Preliminary data from the ICOSS-2 show that the prevalence of COVID-19 was significantly higher among participants involved in irregular day work (20.7%) and shift/night work (25.3%) compared with participants involved in regular day work (18.9%). Furthermore, the prevalence of long-covid (according to WHO criteria) was significantly higher among irregular day workers (11.4%) and shift/night workers (13.6%) compared with regular day workers (8.4%). Conclusion(s) These data indicate that shift/night work, short sleep duration and sleep problems are associated with an increased risk of infections, including COVID-19. Furthermore, preliminary data suggest that shift/night work also is associated with increased risk of developing long-covid. The possible mechanisms involved will be discussed.