Sensitive periods for the effect of bullying victimization on suicidal behaviors among university students in China: The roles of timing and chronicity

Abstract Objective : To examine whether timing and chronicity of bullying victimization (BV) play a significant role in linking exposure to BV to suicidal behaviors in university students. Methods : A multistage stratification sampling method was used to select a sample of 4034 university students (18-23 years, mean age 20.38±1.35 years, 41.9% female). We used latent class analysis and developmental-stage-based characterizations of BV timing and chronicity to explore the sensitive periods for the effect of BV on suicidal behaviors. Results : The prevalence rates of suicidal ideation, plans and attempts among our study participants were 9.9%, 3.0% and 1.3%, respectively. BV during primary school (OR = 2.12, 95% CI: 1.55-2.90) and secondary school (OR = 2.65, 95% CI: 1.80-3.90) was associated with suicidal ideation among university students. We identified four classes of life-course BV experiences (low BV, 73.8%; moderate BV, 18.6%; secondary school BV, 4.4% and persistent BV, 3.2%). Persistent BV was associated with 2.50 times (95% CI: 1.56-3.98), 2.98 times (95% CI: 1.48-6.02), and 6.13 times (95% CI: 2.48-15.14) higher risk of suicide ideation, plans, and attempts, respectively. Both moderate BV (OR=1.75, 95% CI: 1.35-2.26) and secondary school BV (OR=2.01, 95% CI: 1.29-3.12) were positively correlated with suicidal ideation. Furthermore, there was a dose-response relationship between the number of periods of BV and suicidal behaviors. Limitations : This study was a cross-sectional study based on self-reported measures, especially BV experiences in each school stage. Conclusions : This study identifies sensitive periods for the effect of BV on suicidal behaviors among university students in China.