Ageing with Autism: A Later Lifespan Approach to Cognition, Mental Health and Quality of Life

Background: Several commentators have highlighted the need for research on ageing and autism spectrum disorder (ASD), yet few have explored the effects of growing older with autism (Perkins & Berkman, 2012; Wright et al., 2016). Little is known about long-term outcomes for cognitive ability, mental health and quality of life (QoL: Physical, Psychological, Social and Environmental). Cross-sectional studies of older autistic adults have identified poorer QoL compared to typically ageing (TA) groups, but selectively preserved cognitive ability in older autistic adults with average to above-average intellectual ability (Geurts & Lever, 2015), including our own cross-sectional study (Roestorf & Bowler, 2016). We followed our sample in a longitudinal study across 4-years to establish a clearer picture of ageing with autism.

Objectives: Our focus was to understand the effects of growing older with ASD on memory, executive function, language and intellectual ability, as well as autism-related symptoms, mental health and QoL. Our aim was to identify strengths and difficulties that exist for autistic adults across the lifespan, and ways in which QoL can be improved and maintained into later life.

Methods: Our study involved younger and older adults with a confirmed diagnosis of ASD (n=63), and a typically ageing (TA) comparison group (n=44) matched on age (mean=49.79, SD=15.30) and IQ (mean=114.37, SD=14.50). Time-1 (T1) involved cross-sectional comparisons between ASD-TA groups, which extended to longitudinal follow-up at Time-2 (T2; ASD,n=35; TA,n=22; mean interval 2.5 years). Participants completed standardized assessments of cognitive functioning (IQ, memory, language, executive function), and self-report measures of mental health (anxiety, depression) and QoL.

Results: In our original cross-sectional study we reported no age-related effects in ASD, and comparable performance to TA groups on all cognitive measures, but poorer quality of life and higher rates of anxiety and depression in ASD (Roestorf & Bowler, 2016), which replicated the findings from previous observations (Geurts & Vissers, 2012; Lever & Geurts, 2015). In the current, longitudinal study, the preliminary analyses on T2 data show a similar patterning: mental health difficulties at T2 persisted in ASD for anxiety (p<.001, η².33) and depression (p=.002, η².22), the latter presenting greater difficulties for autistic women (p=.004, η².30). The analyses of cognitive data are ongoing, but show promising outcomes for older autistic adults: whereas, younger-ASD participants presented ongoing difficulties in selective cognitive functions (e.g. rapid information processing, p=.017,η².21), a preserved level of ability was observed in older-ASD.

Conclusions: Across our studies, we observed ASD as undergoing a different kind of late-life ageing from that seen in TA. Whilst our cross-sectional work indicated either no difference or “parallel” profiles (Geurts & Vissers, 2012) in older-ASD compared to older-TA adults (Roestorf & Bowler, 2016), longitudinally, we observed a preserved level of cognitive ability in older-ASD adults, despite greater severity of anxiety and depression and poorer QoL. These findings highlight the need for continued mental health supports for autistic adults into later life, and the identification of the cognitive strengths that need to be developed to enable autistic adults to lead autonomous and rewarding lives across the adult lifespan.