Relationship between peripheral blood dopamine level and internet addiction disorder in adolescents: a pilot study

Objectives: To explore the association between peripheral blood dopamine level and internet addiction disorder (IAD) in adolescents, this could be used to explain the neurobiological mechanism of Internet addiction disorder. Methods: 33 adolescents with IAD diagnosed by Young's Internet Addiction Test (IAT) and 33 healthy controls matched by gender and age were investigated in the present study. Peripheral blood dopamine levels of the all subjects were determined by Enzyme Linked Immunosorbent Assay (ELISA). Results: The difference of peripheral blood dopamine level between adolescents with IAD and their controls had reached significant level (t = 2.722, P < 0.05). Furthermore, the plasma dopamine level was significantly correlated with the Internet Addiction Test score (r = 0.457, P < 0.001). The result of rank correlation analysis showed a significant positive correlation between the plasma dopamine level and the weekly online time (r = 0.380, P < 0.01) and there was no significant correlation between the duration of Internet use and the plasma dopamine level (r = 0.222, P > 0.05). Binary logistic regression analysis showed that DA level and weekly online time were significant variables which contribute to internet addiction. Conclusions: The peripheral blood dopamine level is associated with adolescents' internet addiction. The present study provided new evidence in favor of the hypothesis that dopamine played an important role in IAD.