TRISOMY 21: development of syndrome-specific growth charts from a wide Italian cohort and validation of BMI as a predictor of increased risk of metabolic derangement

Purpose: The growth charts for individuals with Down syndrome (DS) available to-date were developed from a cohort of patients from the USA. As diet and environmental factors play a key role on auxological attainment, the growth of patients from the Mediterranean area should be assessed by means of dedicated centiles. Accordingly, we aimed to develop growth charts from a wide Italian population and to provide a metabolic validation for the BMI distribution outlined. Methods: Retrospective, bicentric study. We gathered auxological and biochemical data from two cohorts of Italian children and adolescents with DS assessed every 6- to 12-months between 1992 and 2024. Results: 526 patients were enrolled. We longitudinally retrieved the auxological data recorded in the setting of 2796 clinical evaluations. By assessing height, weight and BMI with reference to age, we outlined the age-dependent distribution of each parameter and developed syndrome-specific growth charts. When comparing our charts with the USA ones, the latter showed a statistically greater upward trendline in weight and BMI. Eventually, we assessed the distribution of triglycerides, cholesterol, glycated hemoglobin and uric acid with reference to the BMI. A higher BMI centile was statistically associated with greater triglycerides, cholesterol, and uric acid levels, and we identified the 90th centile of BMI as a risk threshold for dyslipidemia and hyperuricemia. Conclusion: We developed DS-specific growth charts from a wide Italian population. The comparison with the USA percentiles outlined statistically significant differences in the distribution of weight and BMI, thus highlighting the need of dedicated charts for individuals from the Mediterranean area.