Grant: Doctoral Award - Frederick Banting and Charles Best Canada Graduate Scholarships

Osteoporosis is characterized as a disease of aging, yet its onset may have pediatric roots. The adolescent growth period is believed to be a critical period essential for optimizing bone development. The role of maturation on bone mass and geometry on achieving peak bone strength is controversial. An early onset of puberty may expose males and females to estrogen earlier, providing bones with a greater sensitivity to mechanical loading. This enhanced sensitivity can increase bone strength and serve a protective function for bone development. However, the time prior to puberty is associated with a heightened responsiveness to osteogenic stimulation. The question is does the duration of osteogenic stimulation prior to the onset of maturation override the effects of the hormonal influx during puberty. Therefore, the purpose of this proposed study is to examine the long term relationship between the onset of maturation and adult bone strength. Using individuals from the Pediatric Bone Mineral Accrual Study and the Saskatchewan Growth and Development Study, male and female participants will be classified by maturational category, separating participants into early, average and late maturers. Bone strength indices (bone mass and bone geometry) will assessed during adolescence and in adulthood. Hierarchical multilevel models will be constructed to isolate the independent effects of growth, sex and maturation on bone mass and bone geometry. It is hypothesized that the indices of bone strength will be significantly different between maturational groups with late maturers having significantly greater measures of bone mass and geometry than early maturers during adolescence and in adulthood. Since osteoporosis is believed to have pediatric origins, it is important to identify the long term relationship between bone strength and maturation to develop effective intervention strategies accordingly.