Adolescent self-harm and suicidal thoughts in the ALSPAC cohort: a self-report survey in England.
BACKGROUND
Substantial numbers of adolescents self-harm, but the majority of cases do not reach the attention of medical services, making community studies essential. The prevalence of suicidal thoughts and plans at this age, and the inter-relationships between suicidal thoughts, plans and self-harm remain largely unexplored.


METHODS
Cross-sectional analysis of self-reported questionnaire data collected from members of the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort, England. Respondents (n = 4810) were aged 16-17 years old and have been followed up since birth.


RESULTS
Altogether 905 (18.8%) respondents had ever self-harmed. The prevalence of lifetime self-harm was higher in females (25.6%) than males (9.1%). The most commonly used method was self-cutting: this was used alone or in combination in 73.5% of episodes, compared to 10.0% who took overdoses alone or in combination with other methods. Of those who reported self-harm, 25.3% wanted to die during the most recent episode. Concurrent depression was associated with a greatly increased risk of self-harm (OR 5.43). Only 12.4% of participants sought medical help following their most recent episode of self-harm, although this figure was higher (30.1%) where self-harm was carried out with desire to die. Of the whole sample, 15.8% had ever thought of killing themselves, and 4.3% had ever made plans to kill themselves. Compared to those who had never self-harmed, those who had self-harmed but not wanted to die during the most recent episode were at increased risk of ever having had suicidal thoughts (37.6% compared to 7.8% χ2 =102.3, p < 0.001) and ever making suicidal plans (8.7% compared to 0.7%, χ2 =166.9, p < 0.001). As the frequency of self-harm increased, so did the risk of suicidal thoughts and plans.


CONCLUSIONS
Self-harm and suicidal thoughts are common among 16/17 year olds. Although the majority of self-harm behaviour is not accompanied by a desire to die, all self-harm regardless of motivation is associated with increased risk of suicidal thoughts and plans, particularly when it is carried out repeatedly.
School of Social and Community Medicine, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol BS8 2PS, UK. Judi.kidger@bristol.ac.uk
Judi
J
Kidger
Jon
J
Heron
Glyn
G
Lewis
Jonathan
J
Evans
David
D
Gunnell
D000293:Adolescent; D000294:Adolescent Behavior; D003430:Cross-Sectional Studies; D004739:England / Q000453:epidemiology; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009042:Motivation; D015995:Prevalence; D012307:Risk Factors; D057566:Self Report; D016728:Self-Injurious Behavior / Q000453:epidemiology*; D012737:Sex Factors; D059020:Suicidal Ideation; D013406:Suicide, Attempted / Q000706:statistics & numerical data*; D011795:Surveys and Questionnaires