Socioeconomic Differences in the Association Between Bullying Behaviors and Mental Health in Canadian Adolescents.

BACKGROUND: Bullying and poverty are each associated with poor health in adolescents. We examined socioeconomic differences in the association of bullying and health. METHODS: The 2017/2018 Canadian Health Behaviour of School-aged Children study surveyed 21,750 youth (9-18 years). We used linear regression models to investigate interactive effects of bullying involvement (traditional and cyberbullying) and socioeconomic position (SEP) on self-reported life satisfaction, psychological symptoms, and physical symptoms. RESULTS: Involvement in either form of bullying, as a perpetrator or a target, was associated with worse health and well-being compared to uninvolved youths. Associations of victimization via conventional bullying with low life satisfaction (b = -.33 [-.61, .05]), more psychological symptoms (b = .83 [.27, 1.38]), and more somatic symptoms (b = .56 [.14, .98]) were stronger at lower SEP. CONCLUSION: Socioeconomic disadvantage intensifies the association between bullying victimization and poor health. The intersections of victimization and poverty pose a significant health risk to adolescents.

Association of naturally acquired type-specific HPV antibodies and subsequent HPV re-detection: systematic review and meta-analysis.

BACKGROUND: Understanding the role of naturally acquired (i.e., infection-induced) human papillomavirus (HPV) antibodies against reinfection is important given the high incidence of this sexually transmitted infection. However, the protective effect of naturally acquired antibodies in terms of the level of protection, duration, and differential effect by sex remains incompletely understood. We conducted a systematic review and a meta-analysis to (1) strengthen the evidence on the association between HPV antibodies acquired through past infection and subsequent type-specific HPV detection, (2) investigate the potential influence of type-specific HPV antibody levels, and (3) assess differential effects by HIV status. METHODS: We searched Embase and Medline databases to identify studies which prospectively assessed the risk of type-specific HPV detection by baseline homologous HPV serostatus among unvaccinated individuals. Random-effect models were used to pool the measures of association of naturally acquired HPV antibodies against subsequent incident detection and persistent HPV positivity. Sources of heterogeneity for each type were assessed through subgroup analyses stratified by sex, anatomical site of infection, male sexual orientation, age group, and length of follow-up period. Evidence of a dose-response relationship of the association between levels of baseline HPV antibodies and type-specific HPV detection was assessed. Finally, we pooled estimates from publications reporting associations between HPV serostatus and type-specific HPV detection by baseline HIV status. RESULTS: We identified 26 publications (16 independent studies, with 62,363 participants) reporting associations between baseline HPV serostatus and incident HPV detection, mainly for HPV-16 and HPV-18, the most detected HPV type. We found evidence of protective effects of baseline HPV seropositivity and subsequent detection of HPV DNA (0.70, 95% CI 0.61-0.80, NE = 11) and persistent HPV positivity (0.65, 95% CI 0.42-1.01, NE = 5) mainly for HPV-16 among females, but not among males, nor for HPV-18. Estimates from 8 studies suggested a negative dose-response relationship between HPV antibody level and subsequent detection among females. Finally, we did not observe any differential effect by baseline HIV status due to the limited number of studies available. CONCLUSION: We did not find evidence that naturally acquired HPV antibodies protect against subsequent HPV positivity in males and provide only modest protection among females for HPV-16. One potential limitation to the interpretation of these findings is potential misclassification biases due to different causes.