Clinical risk factors but not bone density are associated with prevalent fractures in prepubertal children

Authors


 Dr G Jones, Menzies Centre of Population Health Research, GPO Box 252-23, Hobart, Tas. 7000, Australia. Fax: +61 3 6226 7704; email: g.jones@utas.edu.au

Abstract

Objective:  The aim of this study was to investigate the association of clinical risk factors and bone density with prevalent fractures in prepubertal children.

Methods:  Bone mineral density (BMD) in lumbar spine, femoral neck and total body bone was assessed by dual-energy X-ray absorptiometry. Clinical data on risk factors were collected by measurement and questionnaires.

Results:   Of 324 children, 32 (10%) had a prevalent fracture (upper limb 69%). Most fractures were due to low-energy falls at home (69%). Children with fractures were older (P = 0.04), had higher levels of sports participation (P = 0.03), lower levels of breastfeeding (P = 0.05) and tended towards higher usage of inhaled corticosteroids in the previous year (P = 0.05). However, both BMD and apparent BMD did not differ between those with and without prevalent fracture. No differences were observed in the proportion of maternal fractures, maternal smoking during pregnancy, asthma history and oral prednisolone in last year (all P > 0.05). A final model incorporating age, weight, height, breastfeeding history, sports participation and inhaled corticosteroid usage accounted for 10% of the variability in the odds of fracture (P = 0.03).

Conclusion:  These results suggest that BMD may be less important than clinical risk factors for total fracture risk in prepubertal children. However, sample size limitations mean that further investigation in larger populations with less heterogeneity in fracture types is warranted.

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