Peer-reviewed article
Risk of subsequent self-harm, suicide attempts and suicide following a first hospital-treated self-harm episode among young people: a population-based cohort study.
Nguyen TD, Karemyr M, Kuja-Halkola R, D'Onofrio BM, Chang Z et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study tracked 77,647 young people aged 10-24 who had a hospital-treated self-harm episode to understand their risk of repeat self-harm, suicide attempts, and suicide. Within one year, 17.3% had subsequent self-harm, 8.3% attempted suicide, and 0.3% died by suicide, with the highest risks occurring in the first month. Risk levels differed by sex and age, with males showing the highest suicide risk and females showing the highest suicide attempt rates. Children aged 10-12 and males had particularly high risks of repeating self-harm in the first month.
Key points
- Within 1 year of first hospital-treated self-harm, 17.3% had subsequent self-harm, 8.3% attempted suicide, and 0.3% died by suicide
- The first month after self-harm carries the highest risk: 8.4% for self-harm, 2.9% for suicide attempt, and 0.04% for suicide
- Males showed the highest suicide risk while females showed the highest suicide attempt rates
- Children aged 10-12 had the greatest first-month self-harm repetition risk, particularly males
- Risk remains elevated throughout the full year, though it declines from peak first-month levels
Limitations
The document does not identify the specific countries included in this study, limiting understanding of geographic applicability. The study is observational rather than interventional, so it cannot assess the effectiveness of prevention or treatment approaches.
Abstract
Background Self-harm in young people is associated with elevated risks for subsequent self-harm, suicide attempts and suicide, particularly during the first year. Yet the trajectory across sex, age and self-harm methods remains poorly understood. Objective To estimate risk for subsequent self-harm, suicide attempts and suicide following a first hospital-treated self-harm event in young people. Methods This study included 77 647 individuals (57.0% female) whose first hospital-treated (ie, within inpatient or outpatient specialised healthcare) self-harm episode occurred between ages 10-24 years during 1973-2019. We estimated cumulative incidence and incidence rate for subsequent self-harm, suicide attempts and suicide at 1 month, 3 months and 1 year following the initial episode. Findings Within 1 year, the cumulative incidence was 17.3% (95% CI 17.0 to17.5) for subsequent self-harm, 8.3% (8.1 to 8.5) for suicide attempt and 0.3% (0.2 to 0.3) for suicide. The highest risks occurred in the first month: 8.4% (8.2 to 8.6) for self-harm, 2.9% (2.8 to 3.0) for suicide attempt and 0.04% (0.03 to 0.05) for suicide. In the first month, the incidence rate of self-harm was 2.97 per 1000 person-days (2.90 to 3.05), falling to 0.55 (0.54 to 0.56) over the year. The suicide attempt rate declined from 0.98 (0.94 to 1.02) to 0.24 (0.24 to 0.25) and the suicide rate from 0.013 (0.009 to 0.019) to 0.007 (0.006 to 0.008). Males exhibited the highest suicide risk and females the highest attempts risk. First-month self-harm risk was greatest among males and children aged 10-12. Conclusions The month following a self-harm episode is marked by an elevated risk of subsequent self-harm, suicide attempts and suicide, yet risk remains elevated over the full year. Clinical implications These findings underscore the need for both acute and sustained prevention efforts. Special attention should be given to males and children aged 10-12 presenting with self-harm of ambiguous intent, as their risk of repetition may otherwise go unrecognised.