Serum levels of brain-derived neurotrophic factor in patients with internet use disorder.

Internet use disorder (IUD) is characterised by excessive internet gaming use and has temporarily been conceptualised as a behavioural addiction. Since brain-derived neurotrophic factor (BDNF) has been hypothesised to be involved in the development and maintenance of addictive disorders, we investigated BDNF expression in IUD. We measured BDNF serum levels in male patients with IUD (n=11) and individually matched healthy controls (n=10). There was no significant difference in BDNF serum levels of patients with IUD in comparison to control subjects. Serum levels of BDNF were not correlated with severity of IUD or clinical and demographic variables in our study. These preliminary findings possibly suggest a different underlying pathophysiology in IUD compared to addictive disorders. Thus, further studies are needed to clarify, whether IUD represents an addictive spectrum disorder, an impulse control disorder or finally an individual diagnostic entity that overlaps with both disease categories.