Timing matters: A meta-analysis on the dynamic effect of stress on salivary immunoglobulin

Abstract

The impact of psychological stress on physiological systems has been a focus of extensive research, particularly in understanding its diverse effects on immune system activity and disease risk. This meta-analysis explores the dynamic effect of acute stress on salivary immunoglobulin-A (S-IgA) levels, a key biomarker for secretory immunity within the oral environment. Analyzing data from 34 samples comprising 87 effect sizes and a total of 1,025 subjects, a multi-level approach is employed to account for the temporal variability in measuring the stress response. The results reveal a significant increase in S-IgA levels peaking around 10 minutes after stress exposure, followed by a return to baseline levels approximately 30 minutes later. In addition, the meta-analysis identified several research gaps of the extant literature, such as limitations in the considered time lag after stress. In conclusion, the findings emphasize the temporal nuances of the stress-induced S-IgA response, which can help to infer potential biological pathways and guide sampling designs in future studies. Further, we highlight the use of a multi-level meta-analysis approach to investigate the temporal dependencies of the interplay between stress and immune functioning.

The influence of everyday emotions on mucosal immunity: An intensive longitudinal modeling approach

“…This effect was moderated on a between-subject level by the individual emotion regulation skills with higher regulation competencies corresponding to a less positive association between negative emotions and S-IgA. These results fit to previous studies that found (i) acute psychosocial stress to lead to increased S-IgA levels (Seizer, Stasielowicz, et al, 2024), (ii) that this immunological response covaries with the level of negative emotions in response to adverse events (Aschbacher et al, 2012;Carroll et al, 2011;Puterman et al, 2014), and (iii) that the psychophysiological stress response may be moderated by emotion regulation skills (Jentsch & Wolf, 2020;Krkovic et al, 2018;Mikolajczak et al, 2007).…”

“…An explanation is that evolutionarily such states of adversity were often associated with potential injuries to the body and an anticipatory upregulation of immune function can help with wound healing and to battle infections (Marsland et al, 2017). Similarly, it has been shown that mucosal immunity is influenced by stress and emotions such as disgust or fear, for example, salivary immunoglobulin-A levels increase in response to acute stress and from the visual perception of disease-related content (persons sneezing and rotten food) (Keller et al, 2022;Schaller & Park, 2011;Seizer, Stasielowicz, & et al, 2024). A better understanding of the connection between emotions and immune responses is essential because it could point to modifiable mechanisms via which psychosocial influences regulate immune system activity (Graham- Engeland et al, 2018;Khandaker et al, 2021).…”