Sex Differences in the Global Prevalence of Nonsuicidal Self-Injury in Adolescents: A Meta-Analysis.

Importance: Nonsuicidal self-injury (NSSI) is a strong predictor of suicide attempts. The prevalence of NSSI has been increasing among female adolescents in North America and Europe, but less is known about trends in other geographical regions. Objective: To examine sex differences in the prevalence of NSSI among adolescents within and between geographical regions. Data Sources: MEDLINE and PsycINFO were searched using the keywords adolescents, self-injury, sex factors, and synonyms for articles published in English between January 1, 2000, and May 10, 2022. Study Selection: Studies were included if they presented original data (any study design), included adolescents aged 10 to 19 years, reported results stratified by sex, and explicitly defined self-injury as behaviors occurring without suicidal intent. Data Extraction and Synthesis: This meta-analysis was registered with PROSPERO and conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Articles were assessed for quality by 2 independent coders (F.M. and J.A.). A random-effects model was used to calculate prevalence. Data were analyzed from July 2022 to April 2023. Main Outcomes and Measures: The prevalence of NSSI in male and female adolescents within and between regions was the main outcome. Odds ratios (OR) with 95% CIs were calculated for community samples. Results: Eight hundred and two studies were screened, and 38 were included (266 491 participants). Across 17 countries, the pooled prevalence of NSSI was 17.7% (female:male OR, 1.60; 95% CI, 1.29-1.98). NSSI was twice as prevalent among female adolescents compared with male adolescents in North America (OR, 2.49; 95% CI, 2.16-2.86) and Europe (OR, 2.08; 95% CI, 1.69-2.58), but not in Asia (OR, 1.00; 95% CI, 0.71-1.41). Conclusions and Relevance: In this meta-analysis of sex differences in global prevalence of NSSI, the female predominance of NSSI observed among adolescents in North America and Europe aligned with rising rates of suicide in these populations. The comparable prevalence of NSSI among male and female adolescents in Asia also aligned with the lower male-to-female suicide ratio compared with other countries. More research is needed to characterize regional (and potentially cultural) sex differences among adolescents with NSSI to prevent and treat the behavior and to understand the possible interplay with corresponding regional trends in suicide.

Suicide Assessment and Prevention in Bipolar Disorder: How Current Evidence Can Inform Clinical Practice.

Bipolar disorder is associated with a considerable risk of suicide, and this fact must be incorporated into management of all patients with the condition. This article highlights the importance of a more nuanced understanding of the factors associated with the increased risk of suicidal behavior in people diagnosed as having bipolar disorder and interventions that could mitigate it. Several sociodemographic, clinical, environmental, and other variables have been associated with suicide attempts or deaths in bipolar disorder. Youths with bipolar disorder are a particularly vulnerable group, and their trajectory of illness could be modified by early interventions. Several medications have been studied regarding their relationship to suicide risk in bipolar disorder, and interventional psychiatry is a newer area of research focus. Finally, community-based approaches can be incorporated into a comprehensive approach to suicide prevention. This article summarizes the current understanding of key variables that can help inform a clinical risk assessment of individuals and interventions that can be employed in suicide prevention in bipolar disorder.