Document resource
Objective In recent years, more research has been devoted to examining whether night-shift work negatively impacts immune system functioning and increases infection risk. However, an overview of the available evidence was lacking. Therefore, this review summarizes the evidence on the association between night-shift work and susceptibility to infectious diseases.Methods A systematic search was conducted in Embase and PsycINFO for studies published until September 2024. Eligible studies included a working population, a comparison between night-shift and non-shift workers, and an infectious disease outcome. The findings were descriptively summarized for common respiratory infections (flu and common cold), SARS-CoV-2 infection, and other infections. Random-effects meta-analysis was used to pool effect estimates.Results A total of 16 articles, covering 14 unique studies and involving 191,320 workers, met the inclusion criteria. Night-shift work was not statistically significantly associated with common respiratory infections (OR=1.11, 95% CI= 0.97–1.27; I²=65.8%, 4 studies). In contrast, night-shift workers had a higher risk of SARS-CoV-2 infection compared to non-shift workers (OR=1.31, 95% CI=1.09–1.58; I²=92.2%, 10 studies). For other types of infections, the number of available studies was insufficient to perform a meta-analysis. Overall, the certainty of the evidence was graded very low, mainly due to the limited number of prospective cohort studies and high heterogeneity between studies.Conclusion The findings of this systematic review and meta-analysis suggest that while night-shift workers are not at higher risk of common respiratory infections, they are at increased risk of SARS-CoV-2 infection. Given the very low certainty of the evidence, future research is needed that employs prospective designs, adjusts for confounding factors, and assesses night-shift work exposure more comprehensively.