Adults with intellectual disabilities: prevalence, incidence and remission of self-injurious behaviour, and related factors.
Self-injury in adults with ID fades in 38% of cases within two years, so keep assessing and keep hope on the table.
01Research in Context
What this study did
S-Johnson et al. (2009) followed adults with intellectual disability for two years. They counted how many showed self-injury at the start, how many new cases appeared, and how many stopped.
The team also looked at what traits went with self-injury. They checked IQ, living place, ADHD, vision, and Down syndrome status.
What they found
About five in every 100 adults had self-injury at the start. Only six in 1,000 developed it during the next two years.
Best news: 38 out of every 100 adults who self-injured at the start were injury-free two years later. Lower IQ, non-family home, ADHD, vision problems, and no Down syndrome raised the risk.
How this fits with other research
Medeiros et al. (2013) watched toddlers with ID for one year and saw little change. S-A et al. now show that across the adult years, change is real: more than one-third recover. Together the studies draw a lifespan line—early stability, later room for remission.
Erturk et al. (2018) found behavioral treatments helped 78% of young children. That work gives us tools; S-A et al. give us hope that, with or without therapy, many adults naturally stop.
Ferguson et al. (2025) urge us to look at emotion regulation in profound ID. S-A et al. add that we should also watch for ADHD and vision loss—factors we can screen and treat today.
Why it matters
If you serve adults with ID, do not assume self-injury is fixed. Re-assess every year. Use the two-year window to teach skills, adjust meds, or change living settings. Target co-occurring ADHD and vision checks; they are modifiable levers. Most of all, share the 38% remission figure with families—it keeps motivation alive.
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02At a glance
03Original abstract
BACKGROUND: Self-injurious behaviour (SIB) is a serious condition, with implications for the person, their family and financial costs to the state providing care. The previously reported prevalence of SIB has ranged from 1.7% to 41%, or 1.7%-23.7% in community studies. There has been little study of remission rate, and incidence has not previously been reported. SIB has been reported to be individually associated with lower ability, autism and communication impairments, but given the inter-relationships between these three factors, it is not known whether they are independently associated with SIB. This study investigates the point prevalence, incidence and remission rates of SIB among the adult population with intellectual disabilities (ID), and explores which factors are independently associated with SIB. METHOD: A prospective cohort study design was used in a general community setting. The participants were all adults (16 years and over) with ID in a defined geographical area. Individual assessments were conducted with all participants. RESULTS: The point prevalence of SIB (as defined by DC-LD) was 4.9%, the two-year incidence was 0.6%, and two-year remission rate was 38.2%. Independently related to SIB were: lower ability level, not living with a family carer, having attention deficit hyperactivity disorder, visual impairment, and not having Down syndrome. Other factors, including communication impairment, autism, and level of deprivation of the area resided within, were not related. CONCLUSIONS: SIB is not as enduring and persistent as previously thought; a significant proportion gains remission in this time period. This should provide hope for families, paid carers and professionals, and reduce therapeutic nihilism. Our study is a first tentative step towards identifying risk-markers for SIB, and developing aetiological hypotheses for subsequent testing. The extent to which SIB may be a relapsing-remitting (episodic) condition requires further investigation, so does further hypothesis-based investigation of factors that might be predictive of incidence of, and remission from, SIB.
Journal of intellectual disability research : JIDR, 2009 · doi:10.1111/j.1365-2788.2008.01060.x