The power threat meaning framework and people with learning disabilities: Psychological professionals’ perspectives

The systematic review aimed to identify whether changes in adaptive behaviour occur as people with Down Syndrome (DS) age, and if so, when and how these changes occur. Both longitudinal and cross-sectional observational studies were included, if they reported on how adaptive behaviour outcomes change with age, for DS participants older than 30. In 2022, a search of three databases (Pubmed, Web of Science, PsycInfo), a database for unpublished theses (ERIC) and reference lists, found 26 eligible studies. Quality assessment revealed considerable bias in at least 5 studies. Given the extensive heterogeneity amongst studies, thematic synthesis was chosen to synthesise the study findings. Tentative results -reveal that declines occur for adaptive behaviour skills after the mid-40s, akin to dementia neuropathology and cognitive declines, with motor skills and receptive language declining first. However, both intra- and inter-individual differences were found, which supports the evidence that dementia in DS is not a normative process and baseline assessments should be utilised to support diagnoses. Other factors such as comorbidities and residential status did not appear to affect declines. Adaptive behaviour assessments should aim to be specific and sensitive to individual baseline functions to avoid ‘floor’ effects, however such measures may be superior to cognitive tests in supporting early detection of dementia in more profoundly intellectually disabled (ID) groups. More research is required to further these findings.