Adolescents with psychiatric symptoms such as attention-deficit\/hyperactivity disorder (ADHD), social phobia, hostility, and depression may be more likely to develop an Internet addiction, according to a report in the October issue of Archives of Pediatrics & Adolescent Medicine. Addiction to the Internet can negatively impact school performance, family relationships, and adolescents' emotional states. Previous studies report that 1.4 percent to 17.9 percent of adolescents are addicted to the Internet in both Western and Eastern societies; therefore, there have been suggestions to add Internet and gaming addictions to the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders. "Identification of the risk factors for Internet addiction is therefore of clinical significance for the prevention of, and early intervention into, Internet addiction in adolescents," the authors write. Science Daily reports that Chih-Hung Ko, M.D., of Kaohsiung Medical University Hospital and Kaohsiung Medical University, Kaohsiung City, Taiwan, and colleagues examined the relationship between psychiatric symptoms such as ADHD, social phobia, and hostility and Internet addiction in 2,293 seventh-graders (1,179 boys and 1,114 girls) from ten junior high schools in southern Taiwan. Researchers also noted differences in the predictive value of these psychiatric symptoms between males and females. Psychiatric symptoms were determined through self-reported questionnaires. Internet addiction was assessed by the Chen Internet Addiction Scale (CIAS) at baseline and at 6, 12, and 24 months with scores ranging from 26 to 104. Participants scoring 64 or higher were classified as being addicted to the Internet. Of all participants, 233 (10.8 percent) were classified as having Internet addiction and 1,929 (89.2 percent) were classified as not having an Internet addiction. The researchers report that although depression, ADHD, social phobia, and hostility were found to predict the occurrence of Internet addiction in the two-year follow-up, depression and social phobia predicted Internet addiction among only female adolescents. Additionally, the most significant predictors of Internet addiction in male and female adolescents were hostility and ADHD, respectively. "These results suggest that ADHD, hostility, depression, and social phobia should be detected early on and intervention carried out to prevent Internet addiction in adolescents," the authors conclude. "Also, sex differences in psychiatric comorbidity should be taken into consideration when developing prevention and intervention strategies for Internet addiction."