Changes in positive affect and mindfulness predict changes in cortisol response and psychiatric symptoms: a latent change score modelling approach.

Objective: This study examined whether and how changes in positive affect and mindfulness predicted changes in cortisol secretion and psychological distress in adaptation to examination stress.

Design: A sample of 105 college students completed a questionnaire set and provided salivary samples before (T1), during (T2) and after (T3) an examination period.

Results: Latent change score modelling revealed that T1-T2 and T2-T3 increases in mindfulness were associated with larger T2-T3 decrease in area-under-the-curve ground of cortisol awakening response (CARg), whereas T2-T3 increases in both positive affect and mindfulness were associated with larger T2-T3 decrease in anxiety symptoms (comparative fit index = .96; Tucker-Lewis index = .93-.95; root-mean-square error of approximation = .04-.08; standardised root-mean-square residual = .08-.10). T1-T2 and T2-T3 increases in positive affect were not associated T2-T3 decrease in CARg, whereas T1-T2 increases in positive affect and mindfulness were not associated with T2-T3 decrease in anxiety symptoms.

Conclusion: The levels of post-stress recovery from anxiety symptoms could depend on concurrent increases in positive affect and mindfulness, whereas the levels of post-stress decline in cortisol secretion could depend on increases in mindfulness both during and after stress. Directions for translating the present findings into stress management programmes in college settings are discussed.