The Association between Movement Behaviours and Mental Health Issues in Adolescents with Neurodevelopmental Disorders.

Purpose: To examine movement behaviour with stress-related biomarkers alongside self-reported mental health issues in adolescents with Neurodevelopmental disorders.

Methods: One hundred fifty-one adolescents with clinically diagnosed NDD and aged between 12-17 years were recruited in Hong Kong secondary schools. Salivary cortisol as a stress-related biomarker and self-reported mental health variables including anxiety, depression, and stress were collected. PA levels (light PA [LPA], moderate PA [MPA], moderate-to-vigorous PA [MVPA], and vigorous PA [VPA]) and sedentary behaviour [SB] were measured using a tri-axial waist-worn accelerometer. Data were analyzed using bootstrapping regression models (bias-corrected method), adjusted for age, gender, and body mass index (BMI).

Results: A significant negative association between MPA and MVPA with self-reported stress and a negative association between MVPA and self-reported anxiety were observed in adolescents with ADHD. A significant positive association between SB and salivary cortisol and a negative association between VPA and salivary cortisol in adolescents with comorbid ASD-ADHD was observed.

Conclusions: Study results demonstrated the association of PA levels and SB with mental ill-being including stress-related biomarkers in both adolescents with ADHD and comorbid ASD-ADHD. Participation in PA, in particular at MVPA intensity, may be essential for mitigating mental health issues in this population. Alternatively, our results could show that mitigating stress and mental health issues is critical for PA participation in adolescents with NDD.