Adverse childhood experiences and bullying behaviours at work among workers in Japan

ObjectivesTo examine the relationship between adverse childhood experiences (ACEs), workplace bullying victimisation and bullying behaviours to subordinates among Japanese workers.MethodsWe conducted an internet-based cross-sectional survey among workers who had enacted 0, 1 and ≥2 types of bullying behaviours that had been directed towards subordinates in the past 3 years (n=309 for each group, total N=927). We assessed ACEs with questionnaires about adverse experiences at home and bullying victimisation at school. The total and controlled direct effects of ACEs on the number of bullying behaviours to subordinates were estimated from a baseline-adjusted and a direct-effect marginal structural ordinal logistic model, respectively.ResultsThere was a positive dose–response association between the level of ACEs and the frequency of workplace bullying victimisation, as well as the number of bullying behaviours enacted at work after adjustment for sex, age and childhood socioeconomic status (both p