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bioRxiv · 10.1101/2021.02.23.432585

Acute and chronic effects of exams week on cortisol production in undergraduate students

Borghi, F.·da Silva, P. C.·Canova, F.·Souza, A. L.·Barbedo Arouca, A.·Grassi-Kassisse, D. M.
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Abstract

University students often experience heightened stress during exam periods, which can trigger psychosocial stress and increase cortisol production. This study aims to investigate both the short- and long-term effects of exam-related stress on the hypothalamic-pituitary-adrenal (HPA) axis, focusing on cortisol production and rhythmicity. Twenty-seven undergraduate students (18-24 years) from a biological sciences program participated in this study. Hair cortisol was measured for two months (October and November), while salivary cortisol was collected during final exams in November to assess cortisol rhythmicity. Saliva samples were taken five times per day across three consecutive days. Hair cortisol levels were significantly higher in November, reflecting increased chronic stress during exam periods. However, salivary cortisol maintained a normal circadian rhythm and preserved cortisol awakening response (CAR), despite elevated stress levels. The rhythmicity of cortisol production remained stable across the exam period, though an increase in cortisol before bedtime on the second and third days suggests heightened stress or anticipatory anxiety. Although university exams induce psychosocial stress, students demonstrated resilience in maintaining cortisol rhythmicity and CAR. These findings suggest adaptive stress responses in students, mitigating the risk of stress-related mental health issues. Further research using hair cortisol analysis could provide insights into cumulative stress exposure and aid in developing preventive mental health strategies for university students.

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Borghi, F., da Silva, P. C., Canova, F., Souza, A. L., Barbedo Arouca, A., Grassi-Kassisse, D. M.. 2021-02-24. Acute and chronic effects of exams week on cortisol production in undergraduate students. https://doi.org/10.1101/2021.02.23.432585

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