The influence of baseline sleep on responses to new stressors: A systematic review.

BACKGROUND

The way we process and memorize stressors has been repeatedly shown to be affected by following sleep periods, particularly rapid eye movement (REM) sleep, but far fewer studies have examined how baseline sleep prior to stressor exposure might shape our stress response after exposure. In this systematic review, we explored how subjectively and objectively measured baseline sleep, including REM sleep, contributes to future stress responses.

METHODS

We identified relevant publications from Web of Science, PubMed, EMBASE, and PsychInfo through August 2024. Human and animal studies were included if they assessed baseline sleep prior to stress exposure, incorporated a stressor, and statistically analyzed stress outcomes in relation to baseline sleep. Studies that only incorporated populations with existing sleep or stress abnormalities were excluded.

RESULTS

Fifty-one independent studies (39 human, 12 animal), consisting of both real-life and experimental stressors met the inclusion criteria. Overall, a majority of studies (n = 34) showed that worse baseline sleep predicted stronger stress responses - a result that was most consistent in human studies measuring sleep subjectively. Animal studies showed varying effects, with sleep disruption often predicting reduced physiological stress response (n = 6). REM sleep yielded varying stress outcomes as well, across species.

CONCLUSIONS

Baseline sleep prior to stressor exposure often acts as a predictor of subsequent stress response. Factors like species, stressor type, the sleep assessment tool, and the stress response measure can influence the direction of the effect. Perceived sleep quality might predict stress coping capabilities more than objective measures like REM levels.