Supplementary Material for: Diurnal profiles of the endocrine stress response in internet gaming disorder

Background: Differences in subjective stress perception and acute response of the hypothalamic-pituitary-adrenal (HPA) axis have been reported in internet gaming disorder (IGD). The present study aimed to further investigate alterations in diurnal profiles of the endocrine stress response system in IGD compared to healthy controls (HC).

Methods: The diurnal course of endocrine markers (salivary cortisol and α-amylase) was investigated in a clinical sample of n = 29 adolescents with IGD compared to n = 26 HC. Further, the effect of unrestricted gaming versus restricted gaming was examined within the IGD group.

Results: No significant differences in salivary cortisol and α-amylase were observed comparing adolescents with IGD and HC. In addition, in the IGD group, there were no significant differences in salivary cortisol and α-amylase between conditions of unrestricted gaming versus restricted gaming. Compared to the HC group, the IGD group showed a significantly higher body mass index (BMI).

Conclusions: Our results indicate no alteration in diurnal profiles of the endocrine stress response in IGD.