ORIGINAL CONTRIBUTION Involvement in bullying and suicidal ideation in middle adolescence: a 2-year follow-up study Hanna-Kaisa Heikkila ¨ • Juha Va ¨a ¨na ¨nen • Mika Helminen • Sari Fro ¨jd • Mauri Marttunen • Riittakerttu Kaltiala-Heino Received: 1 April 2012 / Accepted: 8 September 2012 Ó Springer-Verlag 2012 Abstract The objective of the study was to ascertain whether involvement in bullying increases the risk for subsequent suicidal ideation. A total of 2,070 Finnish girls and boys aged 15 were surveyed in the ninth grade (age 15) in schools, and followed up 2 years later in the Adolescent Mental Health Cohort Study. Involvement in bullying was elicited at age 15 by two questions focusing on being a bully and being a victim of bullying. Suicidal ideation was elicited by one item of the short Beck Depression Inventory at age 17. Baseline depressive symptoms and externalizing symptoms, age and sex were controlled for. Statistical analyses were carried out using cross-tabulations with Chi- square/Fisher’s exact test and logistic regression. Suicidal ideation at age 17 was 3–4 times more prevalent among those who had been involved in bullying at age 15 than among those not involved. Suicidal ideation at age 17 was most prevalent among former victims of bullying. Being a victim of bullying at age 15 continued to predict sub- sequent suicidal ideation when depressive and externaliz- ing symptoms were controlled for. Being a bully at age 15 also persisted as borderline significantly predictive of sui- cidal ideation when baseline symptoms were controlled for. Findings indicate adolescent victims and perpetrators of bullying alike are at long-term risk for suicidal ideation. Keywords Bullying Á Suicidal ideation Á Adolescence Introduction Bullying and suicidal ideation are both common among adolescents. Of adolescents, 10–20 % are frequently involved in bullying, either as bullies, as victims, or as both [12, 15, 22, 27, 31, 40]. As many as 30 % of adolescents present with suicidal thoughts during the developmental phase, and up to 10 % attempt suicide [2, 35]. Both sui- cidal ideation and bullying commonly co-occur with psy- chological symptoms, particularly depression and conduct disorder [2, 13, 14, 27, 31, 32, 47]. Cross-sectional studies have demonstrated a clear con- nection between involvement in bullying and suicidal ideation. Both bullies and victims present with increased levels of suicidal ideation, and adolescents with suicidal H.-K. Heikkila ¨ University of Tampere, Medical School, 33014 Tampere, Finland J. Va ¨a ¨na ¨nen Department of Adolescent Psychiatry, Tampere University Hospital, Box 2000, 33521 Tampere, Finland M. Helminen Á S. Fro ¨jd University of Tampere, Public Health School, 33014 Tampere, Finland M. Marttunen National Institute for Health and Welfare, Box 30, 00271 Helsinki, Finland M. Marttunen Department of Adolescent Psychiatry, Helsinki University Hospital, Box 590, 00029 Helsinki, Finland M. Marttunen University of Helsinki, Faculty of Medicine, Box 20, 00014 University of Helsinki, Finland R. Kaltiala-Heino (&) Department of Adolescent Psychiatry, Tampere University Hospital, Box 2000, 33521 Tampere, Finland e-mail: merihe@uta.fi R. Kaltiala-Heino University of Tampere, School of Medicine, 30014 University of Tampere, Finland 123 Eur Child Adolesc Psychiatry DOI 10.1007/s00787-012-0327-0