Sleep Quality as a Modulator of Immune Response and Infectious Recovery: An Integrative Review

Sleep quality and duration play a central role in regulating the immune response and individual well-being, influencing recovery from infections and maintaining physiological homeostasis.The objective of this study was to analyze, through an integrative review of the literature, the influence of sleep on innate and adaptive immunity, as well as its impacts on susceptibility to infections, vaccine efficacy, and psychophysiological balance.Studies published between 2002 and 2025 were selected from the PubMed/MEDLINE, Scopus, Web of Science, ScienceDirect, and Google Scholar databases.The results show that sleeping less than six hours per night is associated with up to a fourfold increase in the risk of respiratory infections and up to a 50% reduction in antibody titers after vaccination against influenza, hepatitis, and COVID-19.Sleep deprivation and fragmentation raise levels of pro-inflammatory cytokines, such as IL-6 and TNF-α, reduce natural killer cell activity, and impair T and B lymphocyte differentiation, compromising immune memory.In addition, inadequate sleep patterns are associated with worse clinical outcomes, greater severity of viral infections, and reduced quality of life, with a higher prevalence of anxiety and depressive symptoms.It can be concluded that sleep acts as a physiological modulator that determines immunocompetence and well-being, constituting a relevant non-pharmacological strategy for the prevention of infectious diseases and the optimization of the vaccine response.