Prevalence of thinness and its effect on height velocity in schoolchildren

In contrast to childhood obesity, studies involving thin children are much fewer, especially in developed countries. Furthermore, most reports do not address the impact of childhood thinness on height velocity. This study investigated the prevalence of thinness and its effect on height velocity in schoolchildren in the United Arab Emirates (UAE). Weight and height were measured in 29,410 schoolchildren (50.5% females), as part of the health assessment (academic year 2014-2015). The body mass index (BMI) was classified as normal, thinness, overweight, or obese using cutoffs established by the International Obesity Task Force (IOTF), World Health Organization, and Centers for Disease Control.

The median age was 10.2 years (range, 3-19). Using the IOTF scale, one-quarter of the children aged 4-6 years and one-third of the children aged 7-9 years were thin (BMI ≤ 18.5 kg/m²). Thinness was less prevalent (8-10%) in adolescents. Group peak height velocity was delayed 1-3 years in thin children and was higher in children with excess body fat. In conclusion thinness was the highest (25-33%) in children aged 4-9 years of age and their peak height velocity was delayed 1-3 years when compared to the other children.