Dynamic alterations in linear growth and endocrine parameters in children with obesity and height reference values

Background: Obesity can affect linear growth of children but there is uncertainty regarding the dynamics and potential causes. Methods: In the population-based LIFE Child and the obesity-enriched Leipzig Obesity Childhood cohorts (8,629 children, 37,493 measurements), recruited from 1999 to 2018 in Germany, we compared height, growth, and endocrine parameters between normal-weight and children with obesity (0-20 years). Derived from the independent German CrescNet registry (12,703 children) we generated height reference values spe-cific for children with obesity (data collected from 1999 to 2020). Findings: Children with obesity were significantly taller than normal-weight peers, differing at maximum by 7.6 cm (1.4 height, standard deviation scores or SDS) at age 6-8 years. Already at birth, children with obesity were slightly taller and thereafter had increased growth velocities by up to 1.2 cm/year. This growth acceler-ation was unrelated to parental height, but was accompanied by increased levels of insulin-like growth fac-tor-1 (IGF-1), insulin and leptin. During puberty, children with obesity showed a catch-down in height SDS. The reduction in pubertal growth velocity by up to 25% coincided with a decrease in levels of IGF-1 (by 17%) and testosterone (by 62%) in boys and estradiol (by 37%) in girls. We confirmed these alterations in growth in the independent CrescNet cohort and furthermore provide height reference values for children with obesity for open access. Interpretation: Dynamics of linear growth are altered distinctively in different developmental phases in chil-dren with obesity. Early emergence before other profound comorbidities implies predisposition, environ-mental, and/or endocrine factors affecting growth in early life. Height reference values for children with obesity may enhance the precision of clinical health surveillance. Funding: German Research Foundation, German Diabetes Association, EU, ESF, ERDF, State of Saxony, ESPE, Hexal, Novo Nordisk, Pfizer Pharma. (c) 2021 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)