Adaptive and Maladaptive Behaviours and Their Cognitive Correlates in Aging Adults With Down Syndrome

Background: Longer life expectancy in Down syndrome (DS) has shifted concern to age-related declines in everyday functioning. Adaptive and maladaptive behaviours are pivotal to quality of life, yet little is known about their patterns in older adults with DS. Method: Data from 259 cognitively stable adults (25–72 year) in the Alzheimer's Biomarkers Consortium–DS were analysed. Adaptive behaviour (Vineland-3) and maladaptive behaviour (Reiss Screen) were analysed and then regressed on age, intellectual disability level, and cognitive tests. Results: Higher age and greater disability predicted poorer adaptive functioning, but effects waned after cognition was included. General cognition, cued-recall memory, and inhibitory control independently predicted adaptive skills. Maladaptive behaviours were rare, lacked cognitive or demographic predictors, and correlated negatively with adaptive scores. Conclusions: By identifying strengths, vulnerabilities, and predictors of behavioural functioning, this study offers insight into future clinical and caregiving strategies for aging adults with DS.