Paper: "Links between self-injury and suicidality in autism"
This paper was published in 2020, in the journal Molecular Autism.
You can click HERE to download a PDF of the paper.
Keep reading to see a plain English summary, or you can watch my explanatory video!
Why is this an important issue?
In the general public, quite a lot is known about non-suicidal self-injury (NSSI, also known as self-injury or self-harm). This behaviour is associated with mental illness and distress, and people who engage in NSSI seem at higher risk of suicide at a later point in their lives.
Previously, self-injury in autistic people was considered just as one kind of behaviour included under ‘restricted and repetitive behaviours and interests’. However, our research and that of other scientists showed that autistic people without severe communication / intellectual disabilities also engage in NSSI. What these studies did not show was whether NSSI in autistic people is associated with suicidal thoughts and behaviours, in the same way as it appears to be in non-autistic people.
Here is a short video summary. You can open it up to large screen, and turn captions on and off by clicking the 'CC' button.
What was the purpose of this study, and what did the researchers do?
This study was planned as a follow-up to our previous investigation on NSSI in autistic people (link will open in new window). We asked participants from that study to fill out some additional measures indicating whether they had ever experienced suicide ideation (the desire to end their own lives) or attempted suicide. We then examined whether the likelihood of suicide ideation and attempts was greater in those participants who had engaged in NSSI.
In our 77 self-harming participants, we also wanted to see whether particular features and methods of NSSI were especially associated with suicide ideation and attempts. We looked at relationships between suicidality and:
the number of different NSSI behaviours a person engaged in.
the extent that people perceived their NSSI as a problem in their life.
engaging in cutting, scratching/pinching, hitting oneself or punching objects as specific methods of NSSI. These had been the most common types of NSSI in our previous study.
What were the results of the study?
With our participants divided into those who had engaged in NSSI and those who never had, we found that the presence of suicide ideation and suicide attempts could be used to correctly categorise participants. Put plainly, people who had engaged in NSSI were more likely to endorse experiencing suicide ideation and attempts.
In this image, autistic self-harmers are represented in blue; autistic non-self-harmers are represented in orange.
Autistic self-harmers are more likely to have reported experiencing suicide ideation or attempts when asked whether they had ever thought of or attempted suicide.
The more different types of NSSI someone had engaged in, the higher likelihood of their having experienced suicide ideation or attempts.
In our self-harming group, cutting as one form of NSSI behaviour was especially associated with suicide ideation and/or attempts, while scratching/pinching or hitting oneself or other objects was not. This is consistent with other research, which suggests that cutting might be an especially worrying behaviour. It is especially indicative of psychological distress and mental illness, and because it is more painful and visually severe, people who cut themselves may be more likely to develop a reduced fear of pain and a higher tolerance for pain. Some studies suggest that this is important for suicide attempts.
We also looked at relationships between how people felt about their self-injury and their experience of suicide ideation and attempts. Importantly, there was no association - that is, whether or not people perceived their self-injury as a negative thing, just the fact of engaging in self-injury was associated with greater suicidality. This is important because while our previous study suggested that some autistic people may feel very nonchalant or even positive about their self-injury, this finding suggests that NSSI is associated with suicide ideation and/or attempts regardless of how a person feels about it.
What are potential weaknesses in the study?
This study could not determine when NSSI and suicide ideation and/or attempts occurred in relation to one another: it might, for instance, be that some people experienced suicide ideation and/or attempts before the time at which they first started self-harming. It might also be that people who engage in NSSI and people who experience suicide ideation/attempts share something else in common which explains the relationship between them, but we did not measure it here. As such, we can’t be sure that NSSI predicts later suicide risk.
Our analysis lacked detail: we did not differentiate between suicide ideation and suicide attempts. Our measure of how participants felt about their self-injury was also quite a blunt and simplistic way of trying to understand who, within the population of autistic people who self-harm, might be most vulnerable to suicide.
Finally, our sample was not representative of autistic people with intellectual disabilities, non-binary and trans autistic people, or autistic people of colour.
How will these findings help autistic adults now or in the future?
Despite these weaknesses, the study was important in demonstrating that a relationship seems to exist between NSSI and suicidal behaviour - confirming a link that we know exists in the general population. Future, stronger research is needed, but this may help us predict who, within the autistic population, is more vulnerable to suicide. It indicates that certain NSSI behaviours may be especially important for loved ones and clinicians to watch out for (cutting).
The study also suggests that even if people appear unconcerned about their NSSI, that we may need to be worried about their suicide risk. Future research is needed, however, to look more closely at the relationship between how someone perceives their NSSI and how likely it is to be associated with suicide ideation/attempts.
Thank you for reading!
If you found this interesting, you may like to read:
If you are struggling with self-injury or your mental health, please take a look at the resources page - just in case there is something useful for you.