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Reference data for ultrasound bone characteristics in Hungarian children aged 7–19 years

Abstract Backround: Osteoporosis is a common disease and physical activity (PA) has a favourable influence on bone status. Aim: To establish normative data for calcaneal quantitative ultrasound (QUS) bone characteristics in children and to analyse the relationships between PA, anthropometric and bone parameters. Subjects and methods: Hungarian children aged 7–19 (n = 2674; 1325 girls, 1349 boys) provided PA, anthropometric and bone data. QUS parameters were registered with Sonost3000 densitometer (speed of sound: SOS, m/s; broadband ultrasound attenuation: BUA, dB/MHz; bone quantity index (BQI = αSOS + βBUA). Reference centiles of QUS parameters were constructed by LMS method. Multivariate linear regression models were used to analyse the relationships. Results: QUS bone parameters increased with age. There were no gender differences, except in 11- and 19-year-old children, where boys showed higher values. SOS (1497.15 ± 15.72 vs 1494.05 ± 14.81 m/s) and BQI (65.31 ± 16.71 vs 62.26 ± 15.78) were higher in athletic children. The regression model revealed significant relations between SOS and age, relative muscle mass and PA; BUA correlated with gender, morphological age, BMI, relative muscle mass and PA. Conclusions: Changes in the bone parameters among 7–19-year-old Hungarian children depended on age, anthropometric dimensions and the level of PA. The normative data could be used for monitoring QUS bone parameters in children, leading to more effective interventions for healthy bones.