Salivary biomarkers associated with academic assessment stress among dental undergraduates

This study aims to assess the difference in self-perceived stress before and after an academic assessment and its association with the marks scored and to study the association of salivary cortisol, Immunoglobulin A (IgA), and chromogranin A (CgA) with stress levels before and after the assessment. Thirty-one third-year dental undergraduates indicated how stressed they felt on a 5-point rating scale just prior to and immediately after a one-hour written test. Five-minute unstimulated whole saliva samples were also collected at those times to measure salivary cortisol, IgA, and CgA. Students rated significantly higher stress scores before (median [inter quartile range]: 3[1]), compared to after the test (2[2]) (p = 0.015). Higher cortisol levels (mean: 6.32 nmol/l) were observed before than after the exam (mean: 5.16 nmol/l) (p = 0.015). No significant differences were noted between the pre- and post-test saliva samples for salivary IgA and CgA levels. A negative correlation was seen between post-test stress scores and test marks (Spearman's r = -0.325, p = 0.07). Dental students perceived a higher level of stress prior to the test, which declined after that. Pre-test stress scores were associated with raised salivary cortisol, but not IgA or CgA. Students who perceived higher levels of stress after the test generally had poorer results.