RESUMEN
OBJECTIVES: "Internet-addiction" came into common use not only in clinical setting but also in everyday life. But, pathophysiology and diagnostic criteria of the internet addiction remain unknown. Because adolescents are in developing period, they might be vulnerable to the internet addiction, depression and sleep-related problem. The objectives of this study were to investigate the characteristics of internet addiction and its association with sleep pattern and depression in Korean adolescence. METHODS: Subjects were 799 middle and high school students in Seoul, Korea. We administered a self-reported questionnaire including socio-demographic data, Korean versions of Young's Internet Addiction Scale (YIAS), Pittsburgh Sleep Quality Index (PSQI), the Center for Epidemiologic Studies for Depression Scale (CES-D) and questions about internet using patterns. Data of 696 subjects were included in analysis. Chi-square tests were used to analyze proportional differences, and ANOVA with post-hoc tests were used to analyze differences among groups. Partial correlation analyses were performed to analyze the correlation of internet addiction with other variables (two-tailed, p<0.05). RESULTS: Of the 696 participants (grade 2 of middle school;M2 135 vs. grade 1 of high school;H1 238 vs. grade 2 of high school;H2 323), 2.0% (n=14) were internet-addicted (IA), 27.7% (n=193) were over-using (OU) and 70.3% (n=489) were not-addicted (NA). The mean scores of YIAS, PSQI and CES-D scores were 35.24+/-12.78, 5.53+/-3.04 and 16.72+/-8.69, respectively. In higher grade students, average total sleep time was shorter (M2 426.20+/-67.68 min. vs. H1 380.47+/-62.57 min. vs. H2 354.67+/-73.37 min., F=51.909, p<0.001), and PSQI (4.69+/-3.14 vs. 5.42+/-3.15 vs. 5.97+/-2.83, F=8.871, p<0.001) CES-D (13.53+/-8.37 vs. 16.96+/-8.24 vs. 17.87+/-8.84, F=12.373, p<0.001) scores were higher than those of lower grade students. Comparing variables among IA, OU and NA groups, computer using time not for study (96.36+/-63.31 min. vs. 134.92+/-86.79 min. vs. 213.57+/-136.87 min., F=34.287, p<0.001) and portable device using time not for study (84.22+/-79.11 min. vs. 96.97+/-91.89 min. vs. 152.31+/- 93.64 min., F=5.400, p=0.005) were different among groups. PSQI (5.26+/-2.97 vs. 6.08+/-2.97 vs. 7.50+/-4.41, F=8.218, p<0.001) and CES-D scores (15.40+/-8.08 vs. 19.05+/-8.42 vs. 30.43+/-13.69, F=32.692, p<0.001) were also different among groups. YIAS score were correlated with computer using time not for study (r=0.356, p<0.001) and portable device using time not for study (r=0.136, p<0.001). PSQI score (r=0.237, p<0.001) and CES-D score (r=0.332, p<0.001). YIAS score and PSQI score (r=0.131, p=0.001), YIAS and CES-D score (r=0.265, p<0.001), PSQI score and CES-D score (r=0.357, p<0.001) were correlated each other. CONCLUSION: These results suggested that adolescents' internet-addiction was correlated with not only computer and portable device using time not for study but also depression and sleep-related problems. We should pay attention to depression and sleep-related problems, when evaluating internet-addiction in adolescents.