Date of Award
2023
Degree Name
Doctor of Philosophy (College of Health Sciences)
Schools and Centres
Health Sciences
First Supervisor
Associate Professor Paola Chivers
Second Supervisor
Associate Professor Nicolas Hart
Third Supervisor
Dr Timo Rantalainen
Abstract
This thesis examined bone development from childhood into early adulthood in individuals with developmental coordination disorder (DCD) using a life course health development framework. One systematic review was conducted, and four original research studies produced with retrospective data from four unique cohorts in childhood, adolescence, and adulthood. Physical activity was assessed via accelerometry in Finnish child and adult populations and via self-reporting in an Australian population at 17 and 20 years. Bone was assessed via peripheral quantitative computed tomography in adolescents and dual energy x-ray absorptiometry in adults at age 20 years in two Australian cohorts. Bone was assessed cross-sectionally in the adult cohort and longitudinally over six months in adolescents. A mixed model statistical approach was used across studies to account for effects of known physical activity and bone confounders.
Bone deficits were present in individuals with DCD until at least the time of peak bone mass and indicated to be related to reduced physical activity. DCD risk status was associated with deficits in physical activity across the lifespan that may relate to bone impairments, including reduced high impact peaks in boys (Mage=8.8 years) and increased sedentary light activity in adults aged 25 years. These patterns were influenced by other individual factors including individual motor skills and visuomotor impairment. Bone health improvements following engagement in an exercise program in adolescents showed that bone outcomes could be improved via osteogenic physical activity but also reinforced the importance of other aspects of movement on bone gains in this population.
Bone deficits differed by sex in accordance with physical activity differences whereby males showed larger differences based on DCD status than females. Notably, bone deficits were seen in early adulthood for males only. Physical activity patterns were indicative of a cause for this sex-based difference, with a relationship between loading from physical activity and bone only seen in males. These findings have important implications for the health and clinical management of individuals with DCD by confirming the continued vulnerability of this population for osteoporosis risk and fracture however they also provide a potential avenue for improvement via physical activity and exercise engagement.
Publication Details
Tan, J. (2023). Exploration of the Effects of Developmental Coordination Disorder on Skeletal Development from Childhood through to Early Adulthood (Doctor of Philosophy (College of Health Sciences)). University of Notre Dame Australia. https://researchonline.nd.edu.au/theses/380