Self-harm is a global public health problem (Hawton et al., 2003). In England, approximately 200,000 adolescents aged 12 to 17 engage in self-harming behaviour every year without receiving clinical support and additionally, around 21,000 adolescents seek medical treatment following self-harm incidents (Geulayov, et al., 2018; Morgan et al., 2017; Patalay & Gage, 2019).
The rates of self-harm among adults with disabilities are higher (Khazem, 2018; Khurana et al., 2021), but there are varying results when it comes to adolescents with disabilities (King et al., 2019; Tejera et al., 2019).
Hence, this study was conducted to contribute to knowledge advancement and better understand the prevalence and risk factors for self-harm in adolescents, both with and without disabilities.
Adults with disabilities are at higher risk of self-harm compared to those without – what about adolescents?
Methods
The researchers used secondary data from the Millennium Cohort Study; a cohort of children born between 2000 and 2002 (Plewis et al., 2007). The participants were selected randomly by employing child benefit records. The data was collected from adolescents aged 14 and 17 using interviews with parents and adolescents. At age 14, 11,726 adolescents participated in interviews along with parental information, and at age 17, 9528 adolescents took part in the interview.
Disability was assessed with an affirmative response to having physical or mental health conditions lasting 12 months or more. A follow-up response of reduced ability either ‘a lot’ or ‘a little’ was used to distinguish between more and less limiting disability.
The authors also evaluated the lifetime prevalence of self-harm at age 17 and 12-month prevalence of six different self-harm behaviors. Other potential risk factors for self-harm were sexual orientation, exposure to bullying, and self-report measure of depression at age 14.
To address potential biases due to sampling and attrition, inverse probability weighting was done. They also accounted for clustering in survey design using survey data analysis options. Adjusted prevalence rate ratios were estimated to compare the probability of self-harm among adolescents with disabilities to those without disabilities.
Results
Prevalence of disability
Out of 9,528 participants aged 17:
- 12.4% of adolescents reported some form of disability
- 7.7% had less limiting disabilities
- 4.7% had more limiting disabilities
Prevalence of self-harm
The lifetime prevalence of suicide attempts was 25.5% among those with more limiting disabilities, 21.9% among those with less limiting disabilities, and 5.3% among those without disabilities. Adolescents with more severe disabilities had 3.87 times the probability of attempting suicide in their lifetime compared to adolescents without any disability, while those with less severe disabilities had 3.67 times the probability.
Functional impairments
After adjusting for sex, ethnicity and poverty, out of nine functional impairments, those related to mental health, learning, and memory were strongly associated with higher rates of self-harm. For instance, the adjusted prevalence rate ratios (APRR) for suicide attempts were 5.13 (95% CI 3.58 to 7.36) for mental health limitations and 3.64 (95% CI 2.72 to 4.88) for learning/understanding impairments. Functional impairments such as vision and mobility did not show significant association with self-harm behaviors in the last year.
Risk factors
The study identified several risk factors associated with the prevalence of self-harm among adolescents with and without disabilities.
In comparison, adolescents without disability being female, LGBTQ+ orientation, raised in families with poverty income and self-report depression increased the probability of lifetime self-harm among adolescents with disability. While self-harm in the previous year was reported by adolescents with a disability who were female (5 self-harm acts), more limiting disability, and ethnic minority (2 self-harm acts).
For adolescents without disability, adolescents belonging to the ‘non-heterosexuals’ group increased the risk of attempting suicide in their lifetime and self-harm behaviours in the past year, followed by being female sex and bullying at ages 7, 11 and 14 years.
This research suggests that adolescents with mental health and learning difficulties have a higher risk of self-harm.
Conclusions
The study indicates that adolescents with disabilities face a significantly higher risk of engaging in self-harm and attempting suicide compared to their non-disabled peers, with risk more pronounced among those with more limiting disabilities. The study also highlights the complexity of the relationship between disability and self-harm suggesting that the risk is more linked to cognitive and mental health impairments than to physical impairments such as vision and mobility. Being female, or of LGBTQ+ orientation were key factors for self-harm among adolescents with disabilities.
Being a LGBTQ+ adolescent with disabilities was identified as key risk factor for self-harm.
Strengths and limitations
One of the major strengths is that the researchers have addressed a critical gap in the literature by focusing on adolescents with disabilities; a group that is underrepresented in research on self-harm using the data from the Millenium Cohort study which provides a nationally representative sample of adolescents in the UK. The functional impairment categorisation allowed for a detailed analysis of different types of disabilities associated with self-harm behaviours.
With data on self-harm and disability relying on self-report there is the potential of recall bias and social desirability bias for adolescents who might under-report information on self-harming behaviours.
As this study is a cross-sectional design; hence, although associations can be identified, it is not possible to determine whether the disabilities directly cause the increased risk of self-harm.
The study also does not account for changes over time or repeat self-harm. This limits the understanding of how self-harm behaviours have evolved or persisted as adolescents grow older.
While the researchers controlled for several confounders, there may be other unmeasured variables for instance school environment, and family dynamics which could influence the relationship between disability and self-harm.
There is also a scope to explore the prevalence of self-harm among adolescents from ethnic minorities with disabilities; a population that may be further marginalised.
Longitudinal studies are required to better understand self-harm and disability among adolescents.
Implications for practice
The study has some crucial implications for practice. With a strong association of mental health impairment and learning difficulties, there is perhaps a need for mental health services to screen for self-harm risk, and depressive symptoms among these groups in schools and communities. There is certainly a need to strengthen mental health support provided both in schools settings and the wider community. The study also highlights the need for anti-bullying programmes inclusive of students with disabilities, that are accessible and aim to reduce the impact of bullying.
Further qualitative research will help to explore aspects of bullying, and the quality of mental health services perceived by adolescents with disability, teachers, parents, and health care providers to provide a holistic picture. With a higher risk of self-harm among adolescents with disabilities who identify as LGBTQ+ there is a need for counselling and support groups to address the needs of this unique population. Future longitudinal research can be done by following up the adolescents with disability and screening for suicidal behaviours.
The study highlights a need for anti-bullying among adolescents to protect marginalised populations at higher risk of self-harm.
Statement of interests
No conflict of interest.
Links
Primary paper
Other references
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