Interactions between sleep, inflammation, immunity and infections: A narrative review

BackgroundOver the past decades, it has become increasingly evident that sleep disturbance contributes to inflammation-mediated disease, including depression, mainly through activation of the innate immune system and to an increased risk of infections.MethodsA comprehensive literature search was performed in PubMed to identify relevant research findings in the field of immunity, inflammation and infections, with a focus on translational research findings from the past 5 years.ResultsPhysiological sleep is characterized by a dynamic interplay between the immune system and sleep architecture, marked by increased innate immunity and T helper 1 (Th1) -mediated inflammation in the early phase, transitioning to a T helper 2 (Th2) response dominating in late sleep. Chronic sleep disturbances are associated with enhanced inflammation and an elevated risk of infections, while other inflammatory diseases may also be affected. Conversely, inflammation in response to infection can also disrupt sleep patterns and architecture. This narrative review summarizes current data on the complex relationships between sleep, immunity, inflammation and infections, while highlighting translational aspects. The bidirectional nature of these interactions are addressed within specific conditions such as sleep apnea, HIV, and other infections. Furthermore, technical developments with the potential to accelerate our understanding of these interactions are identified, including advances in wearable devices, artificial intelligence, and omics technology. By integrating these tools, novel biomarkers and therapeutic targets for sleep-related immune dysregulation may be identified.ConclusionThe review underscores the importance of understanding and addressing immune imbalance related to sleep disturbances to improve disease outcomes.