Childhood bullying as a cumulative health risk: A dose-response analysis of peer victimization and adult mental and behavioral health outcomes in Saudi Arabia

Childhood peer victimization is increasingly recognized as an adverse childhood experience with long-term consequences for population health. Most existing research treats bullying as a binary exposure, obscuring the dose-response mechanisms through which cumulative victimization generates escalating health risks. This cross-sectional secondary analysis examines whether childhood bullying frequency follows a dose-response gradient associated with adverse adult mental and behavioral health outcomes in Saudi Arabia, and whether socioeconomic disadvantage and family context moderate these associations. We used nationally representative Adverse Childhood Experiences International Questionnaire (ACE-IQ) data from Saudi Arabia (full sample: N = 10,156; analytical sample: N = 4,632). Binary logistic regression models adjusted for socioeconomic status, gender, age cohort, parental supervision, and family structure were estimated for five adult health outcomes: physician-diagnosed anxiety, suicidal ideation, sleep disturbance, tobacco smoking, and substance use. A consistent dose-response gradient was observed. Frequent victims showed higher adjusted odds of tobacco smoking (OR = 6.55, 95% CI 5.81–7.32) and substance use (OR = 2.71, 95% CI 2.26–3.31) compared to those never bullied. Religion-targeted verbal victimization was the strongest predictor of suicidal ideation (OR = 3.01) and substance use (OR = 3.24), independent of bullying frequency. Associations were amplified among socioeconomically disadvantaged respondents. Parental supervision was protective against substance use (OR = 0.45) but paradoxically associated with suicidal ideation, interpreted as a reactive parenting effect. These findings establish childhood bullying as a graded cumulative public health risk amplified by structural disadvantage. Prevention strategies must extend beyond school programs to address structural inequalities and integrate family-based and community-level protective factors.