Diurnal trajectories of salivary cortisol, salivary α-amylase and psychological profiles in oral lichen planus patients

Although many reports have been published on the link between oral lichen planus (OLP) and the stress-related neuro-psycho-endocrine clinical features of the disease over the last 20 years, the data still remain controversial. Therefore, the aim of this study was to explore the personality traits of OLP subjects and assess the subjects' capability of coping with stress challenges. Cortisol and alpha-amylase were measured as reliable markers of the hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system (ANS) activities in salivary samples collected by the participants at their home during the sampling day (07:30, 12:00, and 19:30). Compared with the healthy controls, the OLP patients demonstrated a less effective coping ability, had higher scores in stress perception and loneliness, and had no significant variation in their anxiety and depressive symptoms. The OLP patients also showed dysregulation of the HPA axis activity with a significant reduction of diurnal salivary cortisol production, which was particularly significant in the morning hours. No significant variation was found in the OLP salivary alpha-amylase diurnal fluctuation and production, which was measured at the same time point as that for cortisol. In conclusion, we report that OLP subjects had a reduced capability of coping with stress events and presented a dysregulation of HPA axis activity with hypocortisolism detected in the morning hours.