This study used a sample of Korean adolescents to evaluate: (a) associations between problematic internet use and depression, bipolar disorder symptoms and suicidal ideation; and (b) whether mood disorders mediate the relationship between problematic internet use and suicidal ideation. A total of 795 middle and high school students were recruited (538 girls; mean age, 13.87 ± 1.51 years). The Internet Addiction Proneness Scale for Youth–Short Form (KS-scale) was used to evaluate the presence and severity of problematic internet use. The frequencies of depression, suicidal ideation and probable bipolar disorder were compared between adolescents with and without internet addiction. The associations between the severity of problematic internet use and the severity of depressive symptoms, bipolar symptoms and suicidal ideation were also analyzed. Seventy-five adolescents (9.4%) met the criteria for problematic internet use. The presence of problematic internet use was significantly associated with suicidal ideation (OR = 5.82, 95% CI = 3.30–10.26, p < 0.001) as well as depression (OR = 5.00, 95% CI = 2.88–8.66, p < 0.001). There was a marginally significant association between problematic internet use and probable bipolar disorder (OR = 3.05, 95% CI = 0.96–9.69, p = 0.059). In the path model, problematic internet use significantly predicted depressive symptoms (β = 0.296, 95% CI = 0.214–0.367, p = 0.005), which predicted suicidal ideation (β = 0.699, 95% CI = 0.631–0.751, p = 0.009). Problematic internet use also predicted suicidal ideation directly (β = 0.115, 95% CI = 0.052–0.193, p = 0.006). Conversely, depressive symptoms (β = 0.119, 95% CI = −0.005–0.219, p = 0.040) and suicidal ideation (β = 0.215, 95% CI = 0.089–0.346, p = 0.005) predicted problematic internet use. There is a complex transactional relationship between problematic internet use, depressive symptoms, bipolar symptoms and suicidal ideation, so these conditions must be assessed together during the evaluation of adolescents. Prospective studies are warranted to elucidate the causal relationships between problematic internet use, mood symptoms and suicidal ideation.

Heejeong Yoo. Exp Neurobiol 2015;24:257-72. https://doi.org/10.5607/en.2015.24.4.257

Background: The purpose of this study was to investigate the association between the ionotropic and glutamate receptors, N-methyl D-asparate 2A (GRIN2A) and 2B (GRIN2B), and the metabotropic glutamate receptor mGluR7 (GRM7) gene polymorphisms and attention-deficit hyperactivity disorder (ADHD) in Korean population. Methods: We conducted a case–control analysis of 202 ADHD subjects and 159 controls, performed a transmission disequilibrium test (TDT) on 149 trios, and compared scores from the continuous performance test (CPT), the Children’s Depression Inventory (CDI), and the State-Trait Anxiety Inventory for Children (STAIC) according to the genotype of the glutamate receptor genes. Results: There were no significant differences in the genotype or allele frequencies of the GRIN2A rs8049651, GRIN2B rs2284411, or GRM7 rs37952452 polymorphisms between the ADHD and control groups. For 148 ADHD trios, the TDT analysis also showed no preferential transmission of the GRIN2A rs8049651 or GRIN2B rs2284411 polymorphisms. However, the TDT analysis of the GRM7 rs3792452 polymorphism showed biased transmission of the G allele (χ2 = 4.67, p = 0.031). In the ADHD probands, the subjects with GG genotype in the GRM7 rs37952452 polymorphism had higher mean T-scores for omission errors on the CPT than did those with the GA or AA genotype (t = 3.38, p = 0.001). In addition, the ADHD subjects who were homozygous for the G allele in the GRM7 rs37952452 polymorphism had higher STAIC-T (t = 5.52, p < 0.001) and STAIC-S (t = 2.74, p = 0.007) scores than did those with the GA or AA genotype. Conclusions: These results provide preliminary evidence of an association between the GRM7 rs37952452 polymorphism and selective attention deficit and anxiety found within the Korean ADHD population.

Da-Yea Song, So Yoon Kim, Guiyoung Bong, Jong Myeong Kim, and Hee Jeong Yoo. J Korean Acad Child Adolesc Psychiatry 2019;30:145-52. https://doi.org/10.5765/jkacap.190027