Suicidal ideation is a broad term that encompasses a variety of thoughts and wishes relating to both suicide and death (Harmer et al, 2021). Suicidal thoughts and behaviours are one of the strongest risk factors for death by suicide (Franklin et al, 2017), but as Van Meter et al state (2023), the prevalence of these has not gathered much attention. Understanding risk factors for suicidal thoughts and behaviours may help to reduce the rates of death by suicide, allowing for relevant interventions to be designed and implemented. Establishing which groups in society have the greatest prevalence of suicidal thoughts and behaviours may help us target these groups with effective preventive interventions.
The current study aimed to describe the prevalence of suicidal thoughts and suicide attempts among young people (up to age 21 years), to determine whether the community prevalence of STB (suicidal thoughts and behaviours) is changing over time, and to compare prevalence rates across different places in the world.
The authors searched two bibliographic databases, reference lists of articles and publicly-available reports to identify studies that explored the prevalence of suicidal ideation or attempt in individuals up to the age of 21. Only community samples were included.
A random effects meta-analysis was performed to determine the trend of suicidal thoughts and behaviours over time and to compare rates between regions. Results were also explored by gender, race/ethnicity and age.
Publication bias and influential cases were checked using funnel plots and an extension of Egger’s test. No quality assessment or risk of bias of studies was performed.
The database search retrieved 2,435 papers, with 540 abstracts reviewed. This resulted in 9 effect sizes on the prevalence of passive suicidal ideation, 376 on active ideation, 96 on ideation with a plan, 3 on undefined suicidal ideation and 321 on suicide attempt, all drawn from 369 papers, from 149 countries/territories. The year of data collection ranged from 1981 to 2021, with ages ranging from 6-22.
The table below shows the average prevalence for each measure of suicidal thoughts and behaviours. The authors found that lifetime prevalence was higher for all measures, compared to one year prevalence.
|Active suicidal ideation||16.3% (95 % CI 14.9 to 17.8%)|
|Suicidal ideation with a plan||8.9% (95 % CI 7.5 to 10.5%)|
|Suicide attempt||6.2% (95 % CI 5.5 to 6.9%)|
The authors also found that:
- Younger ages were associated with lower rates of all measures, although rates of suicidal ideation with a plan were not statistically significant
- Female participants were more likely to report all measures
- There were differences in the prevalence rates of each measure between regions. The highest rates of active suicidal ideation were in Eastern European countries (21.6%); suicidal ideation with a plan in South Pacific Islands (23.6%); suicide attempts in South Pacific Islands (16.9%).
The review highlights the prevalence of measures of suicidal thoughts and behaviours, indicating that around 16.3% of those under 21 experience active suicidal ideation. The review suggests that females, those 14 and older, youth of colour and those from the South Pacific have higher prevalence rates of suicidal thoughts and behaviours, but in some subgroups of populations, there is currently little evidence. The authors concluded that “further work is clearly necessary to better understand the proximal factors that contribute to youth suicide risk”.
Strengths and limitations
This review successfully captured papers from all global regions, allowing for a comprehensive, global, analysis of suicidal ideation and behaviours. The authors did not only search for peer-reviewed literature but also explored grey literature and assessed publication bias. However, only two databases were searched which may mean some relevant papers have been missed, particularly those from non-Western countries.
A strength of the paper is the depth of the analysis performed, with results for several different risk factors, and stratified by regions. The study followed PRISMA guidelines but did not pre-register their protocol.
A major limitation of this review is that the authors did not assess the quality of the studies included in their analysis. This means that the findings may be based on very low quality evidence, which would make these results impossible to interpret.
Another limitation of the paper, acknowledged by the authors, is that they were unable to fully capture the trends in each region due to gaps in the available literature. Although the authors found that there were no increases in suicidal thoughts and behaviours, this may be due to the lack of evidence available. Providing a global prevalence rate is of little relevance to specific regions when the rates differ between them. Likewise, there is likely heterogeneity within regions, and therefore, it could be argued that country-specific estimates would have provided a better picture of the situation. When small numbers of effect sizes are available from each region e.g., South Pacific, results should be interpreted cautiously.
Similarly, the lack of evidence available for the racial/ethnic grouping outside of the United States prevents this from being explored as a global risk factor and results, as stated, should only really be interpreted in relation to the United States.
Implications for practice
This review mostly has implications for researchers and policymakers. For researchers, it highlights areas and regions where evidence on suicidal thoughts and behaviours is considerably under-researched, therefore for researchers working on this topic, this should be a priority for further research, including new studies. The study highlights a need for more studies on differences within racial/ethnic groups and other marginalised groups in society (e.g. people from the LGBTQ+ community). Without sufficient evidence, these groups may have consistently high rates of suicidal thoughts and behaviours, but won’t be targets for interventions.
For policymakers and funders, although the evidence suggests that rates of suicidal thoughts and behaviours aren’t increasing, they also aren’t improving and more needs to be done to reduce this, particularly through interventions and funding of more research in specific groups within society and in more granular detail, as opposed to countrywide trends.
Statement of interests
Lucy is a PhD student focusing on global mental health. She has no conflicts.
Van Meter AR, Knowles EA, Mintz EH. (2023) Systematic Review and Meta-Analysis: International Prevalence of Suicidal Ideation and Attempt in Youth. Journal of the American Academy of Child & Adolescent Psychiatry.
Franklin, J. C., Ribeiro, J. D., Fox, K. R., Bentley, K. H., Kleiman, E. M., Huang, X, & Nock, M. K. (2017). Risk factors for suicidal thoughts and behaviors: A meta-analysis of 50 years of research. Psychological bulletin, 143(2), 187.
Harmer, B., Lee, S., vi Duong, T., & Saadabadi, A. (2021). Suicidal Ideation. StatPearls.