Determinants of aggression, and adaptive and maladaptive behaviour in older people with Down's syndrome with and without dementia.
In older adults with Down syndrome, dementia cuts daily living skills but does not spark more aggression.
01Research in Context
What this study did
Hagopian et al. (1999) looked at older adults with Down syndrome.
Some had dementia, some did not.
The team asked: does dementia make aggression rise and daily skills drop?
What they found
Dementia did not raise aggression.
It did lower everyday living skills like dressing or cooking.
So, forget the myth that dementia always brings hitting or yelling.
How this fits with other research
Dall et al. (1997) saw more irritability in a wider ID group with dementia.
The 1999 Down-only sample shows no jump in aggression, so age or diagnosis may shape the link.
Huang et al. (2014) later found dementia explains only 3 % of daily-living drops, backing the small but real skill slide seen here.
Together, the papers say: expect slower self-care, not more blows, when dementia enters Down syndrome.
Why it matters
You can stop waiting for aggression that may never come.
Put your energy into teaching or keeping daily routines like tooth-brushing or laundry.
Track skill loss with a short carer checklist, not just memory tests.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Start a weekly five-item carer checklist for dressing, toileting, tooth-brushing, laundry, and snack prep to spot skill loss early.
02At a glance
03Original abstract
In a cross-sectional study of aggression, and adaptive and maladaptive behaviour in 128 subjects with Down's syndrome (DS), 29 of whom had dementia, the current authors found that the presence of dementia was not predictive of aggression or maladaptive behaviour. However, the level of adaptive behaviour was shown to be lower in subjects with dementia, and in those with lower levels of cognitive functioning, as measured on a rating instrument, the Test for Severe Impairment. Although the presence of aggressive behaviours is not higher in subjects with dementia and DS on cross-sectional review, it remains to be seen whether aggression will increase in individual cases with the onset or progression of dementia. The decline in adaptive behaviour shown in the present study confirms the findings of previous studies and indicates a direction for service development for persons with the dual diagnosis of dementia and DS.
Journal of intellectual disability research : JIDR, 1999 · doi:10.1046/j.1365-2788.1999.043005393.x