Year: 2013
Type: dissertation
Study design: Observational Study
Abstract: Osteoporosis has been described as a paediatric disease with geriatric consequences. This \nthesis explored the associations between proximal, historical and predictive genetic and \nenvironmental factors affecting bone mass and bone size in socio-economically- and \nenvironmentally-disadvantaged black and -advantaged white pre- and early-pubertal South \nAfrican children. Data were collected from 476 children (182 black boys, 72 white boys, 158 \nblack girls, 64 white girls) of mean age 10.6 years (range: 10.0-10.9), 406 biological mothers and \n100 biological fathers. The main findings were that black children and their parents compared to \nwhite, had greater DXA-measured BMC at the femoral neck regardless of the way in which \nBMC was corrected for size (height, weight, BA and/or BAPC) and greater bone strength. \nLumbar spine BMC was greater or similar depending on which measures were used to correct \nBMC for size. At the whole body, mid radius and distal one third of the radius, BMC varied \nbetween children, and between their parents, and were dependent on which measures were used \nto correct BMC for size. Weight at 1 year (WT1), length at 1 year (LT1) and birth weight (BW), \nwere significant predictors of BMC of the femoral neck (P<0.05-0.01) after correcting BA and \nBMC for race/ethnicity, gender, age, socioeconomic status, bone age, height and weight at 10 \nyears. Maternal and paternal heritability was estimated to each be ~30% in both black and white \nsubjects. The main conclusion was that ethnicity is the single most important proximal factor \naffecting bone mass and bone size in 10 year old South African children. Black children \ndemonstrate a superior bone mass and bone strength at the femoral neck. Historical and \npredictive factors however indicate that black children have not been programmed for optimal \nbone health in utero and early life, nor are contemporary environmental factors favourable for \nthe maximisation of peak bone mass. This cohort may be at risk of developing osteoporosis as an elderly population, particularly at the lumbar spine and forearm.
Author: Linda Van der Lingen
Language: English
Subfield: Orthopedics and Sports Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2254448712