Reference charts for body composition parameters by dual-energy X-ray absorptiometry in European children and adolescents aged 6 to 18 years-Results from the Austrian LEAD (Lung, hEart, sociAl, boDy) cohort.

Background: DXA is a widely used technique to assess body composition. Reference values based on a large general population cohort of European children and adolescents were missing. The aim of this study was to provide age- and sex-specific reference percentiles of body composition parameters for European children and adolescents and to compare them to the American NHANES cohort. Additionally, exponents accounting best for height biases were analysed.

Methods: DXA scans of 1573 participants, aged 6 to 18 years, recruited from 2011 to 2019 by the Austrian LEAD study, a representative population-based cohort, have been used to create reference charts using the LMS model.

Results: Reference charts displaying percentile curves and the corresponding reference values are provided. Fat mass parameters were higher in females, while lean mass parameters were higher in males. Compared to the NHANES cohort medians of FMI and LMI were always lower. For FMI, BMI, LMI and ALMI the best fitting exponent were 2.5, 3, 3 and 3.5 respectively CONCLUSIONS: The present study provides reference charts for children and adolescents aged 6 to 18 years, for body composition parameters assessed by DXA. The charts enable comparison to a European general-population cohort and indicate that reference populations should be chosen with caution.