31608
The Relation between Motor Abilities, Adaptive Behavior, and Quality of Life: A Study of Middle-Aged Adults with ASD
Emerging evidence suggests motor skill deficits are a cardinal feature of ASD and reliably predict other ASD-related difficulties in cognitive functioning and adaptive behavior (MacDonald et al., 2015; Travers et al., 2017). However, few studies have examined motor-related difficulties in later adulthood and their relation to adult outcomes.
Objectives:
To assess motor abilities in middle-aged adults with ASD, and examine the relation between motor performance, adaptive behavior (e.g., daily living skills), and quality of life (QoL).
Methods:
Participants were 55 adults with ASD in mid-adulthood (27-57 years of age, M=37 years) who had previously participated in a larger study of adult outcomes (e.g., employment, education, QoL). All adults were diagnosed with an ASD during childhood (M=6 years). Participants completed a comprehensive in-person assessment including diagnostic (ADOS-2 and CARS-2), intellectual functioning (Stanford-Binet-5), adaptive behavior (VABS-II, Waisman ADL), and motor ability [grip strength (GS), finger tapping test (FTT), D-KEFS Motor Speed, Timed-up-and-go (TUG)]. Childhood assessment data from the Vineland Adaptive Behavior Scale (VABS) was also available and used as a covariate in the analyses. Three participants were unable to complete the motor measures and dropped from analyses.
Results:
Examination of motor performance revealed similar GS (M=51.6,SD=19.6) and FTT (M=47.1,SD=15.3) between dominant and non-dominant hands (p’s≥.06). Average completion time (seconds) for D-KEFS Motor Speed and TUG test was 62.5s (SD=45.2) and 10.63s (SD=3.0), respectively. Across tasks, motor functioning was substantially below what would be expected for individuals without ASD and similar intellectual functioning (Cuesta-Vargas & Hilgenkamp, 2015). FTT, TUG, and GS were significantly correlated with adaptive behavior (r’s ≥ .43, p’s < .03), however only FTT and GS correlated with QoL (r’s ≥ .27, p’s < .05). Motor Speed was not significantly correlated with the adult outcome measures (r’s < .21, p’s > .29). To assess the relation between motor functioning, adaptive behavior, and QoL, separate hierarchical linear regressions were conducted for each motor measure by first entering the adult with ASD’s age, symptom severity (CARS-2), IQ, childhood VABS as covariates, followed by motor performance. Results indicated that of the four motor measures only FTT remained a significant predictor of adaptive behavior and QoL after controlling for the above mention variables (VABS-II: R2=.06, β=.26,p=.04; Waisman ADL: R2=.12, β=.38,p=.02; QoL: R2=.23, β=.53,p=.003). Similar findings were also observed for the VABS-II subscales.
Conclusions:
Relative to published norms, the current findings suggest this middle-aged cohort of adults with ASD exhibit sub-optimal performance across a range of motor-related tasks. While GS and FTT were among the strongest motor abilities related to adaptive behavior and QoL, only finger tapping speed remained a significant predictor after controlling for age, IQ, ASD symptom severity, and childhood adaptive behavior. These findings document the important role of fine motor ability in predicting real-world outcomes in middle-aged adults with ASD. In light of emerging evidence suggesting poor adult outcomes in ASD, these findings point to specific motor abilities that could to be targeted in interventions to maintain, or possibly improve functional autonomy and quality of life in this aging population.