Some behaviours associated with a diagnosis of autism don't make for great dinner table discussion. Self-injurious behaviours (SIBs), as exemplified by head banging, hair pulling and eye gouging must rank as some of the more distressing facets of [some] autism insofar as their potential effect on the person and also the people around them.
These and other types of behaviour commonly headed under the category of so-called 'challenging behaviours' have tended not to be too evident when it comes to the public depiction of autism it has to be said. I can appreciate why, but what this can mean is that such issues tend to get 'brushed under the carpet'. In recent times however, there does seem to be a greater willingness for research to delve into such behaviours .
The paper by Caroline Richards and colleagues  (open-access) looking at the persistence of such behaviour(s) and the potential correlates associated with their persistence is a welcome piece of research added to the research interest. Highlighting how for a small research sample of 67 children/young adults with autism over three-quarters reported SIB persisting over a 3-year period, the data provide some interesting insights into the nature of this issue and, potentially how it should be screened for and managed.
Based here in Blighty, researchers initially managed to recruit 190 participants, the data for some of whom were previously published . As perhaps one might expect, the follow-up after on average 36.4 months had elapsed was not so well-populated. No mind, various findings are reported including that "the presence, topography and severity of self-injury were persistent and stable over three years" and that "individuals with self-injury were significantly more likely to be non-verbal than those who did not engage in self-injury." Further: "individuals with self-injury were significantly more likely to be less able and non-verbal and to show higher levels of stereotyped behaviour, compulsive behaviour, insistence on sameness, overactivity, impulsivity, repetitive behaviour and impairments in social interaction."
There is quite a bit more to do on this topic including facing up to issues around the small (eventual) participant size and the reliance on 'a questionnaire pack' as the chosen method of assessment. The authors also talk quite a bit about how some of the behaviours observed in connection with self-injury - impaired behavioural inhibition - might overlap with other diagnoses such as attention-deficit hyperactivity disorder (ADHD) but as far as I can see, they did not directly screen for ADHD outside of the use of something called The Activity Questionnaire (TAQ). I might also have liked to have seen a little more information about how parents/professionals had 'tackled' SIB in this cohort and what effect that might have had on results. Investigations remain.
Having said all that, the insights provided by the Richards article are important and provide plenty of food for thought when it comes to SIB and autism. Without trying to generalise SIB to all autism nor to come across as portraying too negative an image of what autism can mean to someone, recognition and management (dare I say treatment) of such behaviours when present should really be a priority .
 Maddox BB. et al. Untended wounds: Non-suicidal self-injury in adults with autism spectrum disorder. Autism. 2016 May 12. pii: 1362361316644731.
 Richards C. et al. Persistence of self-injurious behaviour in autism spectrum disorder over 3 years: a prospective cohort study of risk markers. Journal of Neurodevelopmental Disorders 2016; 8: 21.
 Richards C. et al. Self-injurious behaviour in individuals with autism spectrum disorder and intellectual disability. J Intellect Disabil Res. 2012 May;56(5):476-89.
 Lee Y-H. et al. Cataract secondary to self-inflicted blunt trauma in children with autism spectrum disorder. Journal of American Association for Pediatric Ophthalmology and Strabismus. 2016. May 17.
Richards, C., Moss, J., Nelson, L., & Oliver, C. (2016). Persistence of self-injurious behaviour in autism spectrum disorder over 3 years: a prospective cohort study of risk markers Journal of Neurodevelopmental Disorders, 8 (1) DOI: 10.1186/s11689-016-9153-x