Keywords
Immune System
Systematic Review
How to Cite
Abstract
Introduction: Anxiety is a disorder characterized by intense feelings of fear, worry, nervousness, and distress, typically associated with the anticipation of a perceived threat. Scientific evidence indicates that elevated levels of anxiety can impair immune function by altering physiological parameters and increasing susceptibility to immune-related diseases.
Objective: This study aimed to investigate the effects of anxiety on the immune system through a systematic literature review.
Methods: Searches were conducted in the PubMed, ScienceDirect, and Scopus databases, including original studies published within the last ten years, in Portuguese or English, conducted in humans and evaluating immunological parameters associated with anxiety. Methodological quality and risk of bias were assessed using the Joanna Briggs Institute (JBI) critical appraisal tools according to study design.
Results: After applying the eligibility criteria, 16 studies were included. The analysis demonstrated that anxiety is associated with adverse changes in immunological and hormonal parameters. Specifically, the findings indicated increased levels of inflammatory cytokines, elevated circulating lymphocytes, and higher cortisol and adrenocorticotropic hormone (ACTH) levels, suggesting activation of the hypothalamic–pituitary–adrenal (HPA) axis. Additionally, an association between anxiety and increased C-reactive protein (CRP) levels was observed, indicating a potential link with chronic inflammatory processes.
Conclusion: Most studies presented a moderate risk of bias. Overall, the evidence suggests that anxiety disorders exert a significant impact on immune function, highlighting the importance of effective anxiety management strategies to promote immune health and quality of life.
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