The association between bullying-victimisation and sleep disturbances in adolescence: Evidence from a twin study

Bullying-victimisation has been associated with sleep disturbances. This study investigated the degree to which subtypes of bullying-victimisation in adolescence are linked with sleep disturbances. Genetic and environmental contributions underlying bullying-victimisation and sleep disturbances were investigated. Participants (3,242-5,076 pairs) from a longitudinal community twin study reported on their bullying-victimisation at the age of 14 years, and sleep quality and insomnia symptoms at age 16. Regression analyses were used, accounting for the role of individual and family factors. Structural equation twin model fitting was conducted. Bullying-victimisation was modestly associated with sleep quality and insomnia symptoms (r = 0.22-0.23) and a similar strength of associations was found across bullying-victimisation subtypes (r = 0.11-0.22). Bullying-victimisation, sleep quality and insomnia symptoms were predominantly influenced by genes (25-59%) and non-shared environments (40-62%). The association between bullying-victimisation and sleep quality was explained by genetic and non-shared environmental influences. For insomnia symptoms and sleep quality, the association with bullying-victimisation was in part explained by a genetic overlap. Associations between bullying-victimisation and sleep disturbances are not limited to specific aspects of bullying-victimisation but appear to exist for all subtypes. These findings stimulate research questions regarding the mechanisms underlying these links. For example, could certain heritable traits, such as temperament, increase vulnerability to experiencing sleep disturbances and being bullied? Research on bullying and sleep should aim to take the role of genetic predisposition into account, while also noting that it is not the only causal influence. Understanding more about these pathways could strengthen the development of techniques to prevent these difficulties from occurring.