Fractures in school age children in relation to sex and ethnic background: The Generation R Study.

Fracture rate in childhood is increasing and its consequences may affect health and developmental processes and cause school absence and restricted activity days. There are scarce epidemiologic studies regarding fractures in children. The aim of this study was to evaluate if pediatric fractures show disparities across sexes and ethnic groups. This study was conducted based on data from 3632 participants of the Generation R Study. Prevalent fractures were assessed using a questionnaire at a mean age of 9.7 years. Child's ethnicity was determined based on country of birth of the parents using questionnaires (geographic ancestry) or admixture analysis (genetic ancestry). Associations between fracture occurrence and sex or ethnicity were evaluated using logistic regression models adjusted for age, weight, lean mass fraction, bone mineral density (BMD) and sex/ethnicity. Fracture was reported for 525 (14.5%) children. The great majority of these children were classified as European (N = 3164), followed by African (N = 283) and Asian (N = 185) based on geographic ancestry. Similarly, the highest proportion of Europeans was observed based on genetic ancestry. Prevalence of fractures was not different between boys and girls, even after adjustment for possible confounders (OR: 1.03, 95% CI 0.84-1.27, p-value = 0.8). However, odds of prevalent fractures were two times higher in European when compared to Asian children (OR: 2.01, 95% CI 1.17-3.45, p-value = 0.01), and 1.5 times higher when compared to African children (OR: 1.50, 95% CI 1.00-2.26, p-value = 0.05). Overall, in this study, European children showed a highest risk of prevalent fractures independently of factors such as body composition and BMD, while no difference in the prevalence of fractures between boys and girls was observed.