Salivary cortisol/DHEA ratio response to acute academic stress and its association with performance in middle-to-late adolescents.

Objectives: Neuroendocrine coupling across adolescent transition conditions a stage of heightened variability in hypothalamic-pituitary-adrenal axis stress reactivity, likely impacting the adaptive physiological response to psychological stressors during adolescence. This study aimed to assess the salivary cortisol, DHEA, and cortisol/DHEA ratio variation in response to acute academic stress and its association with academic performance.

Methods: A longitudinal observational study with a combined event- and time-based protocol was conducted. Twenty-two middle-to-late adolescents (mean age 17.6 ± 0.3 years) performed a 60-minute written examination in which saliva samples for cortisol and DHEA determination were collected at four points: before the examination and after its completion, and at the same time points on a control day. Academic performance was assessed based on the examination score determined by the number of marks awarded for each correct response.

Results: Salivary cortisol (p = 0.012) and cortisol/DHEA ratio (p = 0.004) were significantly higher at pre-examination. When compared to students with low academic performance, high-achieving students exhibited higher cortisol levels (p = 0.026) and a higher cortisol/DHEA ratio (p = 0.017) at post-examination. Bivariate analysis showed a moderate positive correlation between academic performance and the post-examination cortisol/DHEA ratio (rs(20) = 0.44, p = 0.039), which significantly predicted academic performance (F(1,20) = 4.63, β = 0.09, CI 95% [0.003, 0.171], p = 0.044).

Conclusion: In middle-to-late adolescents, the salivary cortisol/DHEA ratio response to acute academic stress is positively associated with academic performance. The findings of this study provide evidence of the neuroendocrine response to a cognitive demanding stressor as an adaptive mechanism likely mediated by the effect of an acute cortisol surge in cognition enhancement.