Autism, ADHD and school absence are risk factors for self-harm

Research links school and hospital data.

Research led by King’s College London and South London and Maudsley NHS Foundation Trust has analysed factors associated with self-harm in over 111,000 adolescents aged 11-17 years old.

Published in BMC Medicine the study found that the risk for self-harm presenting to hospital emergency departments was nearly three times higher for boys with autism spectrum disorder (ASD) compared to boys without ASD. 

Attention Deficit Hyperactivity Disorder (ADHD) was a strong predictor of self-harm for both boys and girls with approximately a four-fold increased risk for self-harm amongst those with ADHD. 

Absence from school was also associated with increased risk for self- harm: for those young people with less than 80 per cent attendance the risk of hurting themselves was three times greater.

Part-funded by the National Institute for Health and Care Research (NIHR) Maudsley Biomedical Research Centre and the Wellcome Trust, this is the first long-term investigation of adolescent self-harm and ASD using linked school and hospital data in England. The research provides valuable insight into those groups most at risk, representing an important step in developing preventative strategies for self-harm.  

Dr Johnny Downs, Consultant Child & Adolescent Psychiatrist at South London and Maudsley and NIHR Clinician Scientist at the Department of Child & Adolescent Psychiatry, King’s College London and senior author on the paper said: “By linking these large-scale datasets, we have been able to understand which groups of young people may be most vulnerable to self-harming. Crucially we are using local data, so it has direct implications for the NHS Trust where I work and can improve our targeting of mental health interventions within South London schools. Another important aspect of this study is that any region in England could use the same approach, as the school and hospital data already exist and can be linked.” 

Self-harm is common in adolescents and research suggests about 1 in 5 self-harm. Around 12 per cent of episodes of adolescent self-harm are seen at emergency departments and these are the young people most likely to be at risk of suicide.

Researchers connected data on hospital attendance for self-harm to educational data. This enabled examination of education factors such as school attendance, special educational needs and free school meal status as well as data on mental health service use. The study assessed data from 113,286 young people from four boroughs in South London collected between 2009-2013.

By analysing data from the National Pupil Database on whether children had been assigned special educational needs for ASD, the study showed that boys with ASD were at greater risk of self-harm than boys without ASD. This pattern was not observed amongst girls with ASD but in general the risk of self-harm was higher in girls than in boys (1.5% compared to 0.3% in boys).

Emily Simonoff, Professor of Child & Adolescent Psychiatry at King’s College London, and Theme Lead for Child Mental and Neurodevelopmental Disorders in the NIHR Maudsley Biomedical Research Centre who is a co-author on the paper said: “We know that autistic adults have higher rates of premature death, including increased rates of suicide.  Self-harming behaviours, like those explored in the present study, may be the precursor to more serious suicide attempts, so early identification and proactive intervention when self-harm first appears is very important. Autistic people often have more difficulty regulating their emotions, which can contribute to high levels of distress and, because of the communication impairments experienced by many autistic people, professionals may not appreciate the level of distress they are experiencing and the seriousness of these behaviours.”

The study also found adolescents who had attended mental health services for ADHD were at four times the risk of self-harm than those who had not attended services for ADHD. School exclusion and absence were also identified as risk factors.

Joint first author Dr Emily Widnall who conducted the research while at King’s and is now Senior Research Associate in Public Health at University of Bristol said: “Our research has shown that adolescents who spent time away from school, either through exclusion or absence, have an increased risk for self-harm compared to young people who are in school most of the time. Linking educational data to mental health data has an important role to play in answering public health research questions in child and adolescent mental health and can help identify where more support is needed within schools.”

The study also revealed findings that may need further research to unpick the possible underlying mechanisms. For example, the finding that girls with ASD were at no higher risk to self-harm than those without ASD could be explained by underdiagnosis of ASD in girls.

The study also found that those who spoke English as a second language were at a lower risk to self-harm than those with English as their mother tongue.

“Taken at face value the results suggest young people who are resident in London but non-native English speakers, have less mental health difficulties,” commented Dr Downs.  “But there could be other influences at work which could mean that these young people are self-harming and not presenting to services or are expressing their distress through other means such as misusing substances.”

The study used the Clinical Record Interactive Search (CRIS) platform to analyse clinical e-records from South London and Maudsley NHS Foundation Trust. CRIS was developed by the NIHR Maudsley BRC.

‘Autism spectrum disorders as a risk factor for adolescent self-harm: a retrospective cohort study of 113,286 young people in the UK’ is published in BMC Medicine. DOI: 10.1186/s12916-022-02329-w

After the embargo has lifted it will be available here:

The labels have been added to this press release as part of a project run by the Academy of Medical Sciences seeking to improve the communication of evidence. For more information, please see:

About King’s College London and the Institute of Psychiatry, Psychology & Neuroscience

King’s College London is one of the top 35 UK universities in the world and one of the top 10 in Europe (QS World University Rankings, 2020/21) and among the oldest in England. King’s has more than 31,000 students (including more than 12,800 postgraduates) from some 150 countries worldwide, and 8,500 staff. King’s has an outstanding reputation for world-class teaching and cutting-edge research. The Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King’s is the premier centre for mental health and related neurosciences research in Europe. It produces more highly cited outputs (top 1% citations) on mental health than any other centre (SciVal 2019) and on this metric we have risen from 16th (2014) to 4th (2019) in the world for highly cited neuroscience outputs. World-leading research from the IoPPN has made, and continues to make, an impact on how we understand, prevent and treat mental illness and other conditions that affect the brain. @KingsIoPPN

South London and Maudsley NHS Foundation Trust

South London and Maudsley NHS Foundation Trust is a large and complex multi-site provider of mental health services – providing the widest range of NHS mental health services in the UK. We aim to make a difference to people’s lives by seeking excellence in all areas of mental health and wellbeing.

Our 6,000 staff serve a local population of 1.3 million people and we offer more than 260 services including inpatient wards, outpatient and community services across Lambeth, Lewisham, Southwark and Croydon. We also provide substance misuse services for people who are addicted to drugs and alcohol.

As well as serving the communities of south London, we provide more than 20 specialist services for children and adults across the UK including perinatal services, eating disorders, psychosis and autism.

The National Institute for Health and Care Research (NIHR)

The mission of the National Institute for Health and Care Research (NIHR) is to improve the health and wealth of the nation through research. We do this by:

  • Funding high quality, timely research that benefits the NHS, public health and social care;
  • Investing in world-class expertise, facilities and a skilled delivery workforce to translate discoveries into improved treatments and services;
  • Partnering with patients, service users, carers and communities, improving the relevance, quality and impact of our research;
  • Attracting, training and supporting the best researchers to tackle complex health and social care challenges;
  • Collaborating with other public funders, charities and industry to help shape a cohesive and globally competitive research system;
  • Funding applied global health research and training to meet the needs of the poorest people in low and middle income countries.

NIHR is funded by the Department of Health and Social Care. Its work in low and middle income countries is principally funded through UK Aid from the UK government.




Observational study




Autism spectrum disorders as a risk factor for adolescent self-harm: a retrospective cohort study of 113,286 young people in the UK

The above article has been published from a wire source with minimal modifications to the headline and text.

more recommended stories