ESPE Yearbook of Paediatric Endocrinology

To read the full abstract: Int J Obes 2019; 43(2): 384–91

Studies regarding brown adipose tissue (BAT) activity in children are scarce due to the difficulties in detecting BAT by imaging and the need for elaborate techniques to measure BAT activity. Here, prepubertal children born small for gestational age (SGA, n=41) and children born appropriate for gestational age (AGA, n=45) were examined in order to investigate whether prematurity has an impact on BAT activity. This is of special interest since it has been shown that the activity of BAT is important for insulin sensitivity and a healthy lipid profile, and children with SGA have corresponding metabolic impairments.

The authors measured BAT activity using ‘thermal imaging’: the temperature at the supraclavicular region (SCR) before and after a cold stimulus was measured by infrared thermal imaging, and the area of thermally active SCR (increase after cold challenge, ΔArea_SCR) was calculated as a surrogate index of BAT activation. They found no difference in BAT activity between SAG and AGA children. However, a sex difference was detected, with a higher BAT activity in AGA girls compared to AGA boys. Moreover, BAT activity was negatively associated with HOMA-IR, hs-CRP, liver volume, and liver fat.

BAT activation peaks during puberty and declines during adulthood (1). Recent papers have shown that BAT activity in children is positively associated with muscle volume (2) and bone mass (3), suggesting a role for BAT activity in growth and development. Until now, there was no study investigating relationships between BAT activity and metabolic health and cardiometabolic risk factors. The present paper shows for the first time positive associations of BAT activity in children with indicators of metabolic good health. These associations are present already in early childhood. Moreover, the described difference between girls and boys, which has also been described elsewhere (1), could not be seen in SGA children, possibly indicating limited activation properties in girls born preterm. Studies using more accurate techniques, such as MRI to detect BAT volume, are needed to corroborate these findings.

References: 1. Gilsanz V, Smith ML, Goodarzian F, Kim M, Wren TA, Hu HH. Changes in brown adipose tissue in boys and girls during childhood and puberty. Journal of Pediatrics. 2012;160(4):604-9.e1

2. Gilsanz V, Chung SA, Jackson H, Dorey FJ, Hu HH. Functional brown adipose tissue is related to muscle volume in children and adolescents. Journal of Pediatrics. 2011;158(5):722–6.

3. Ponrartana S, Aggabao PC, Hu HH, Aldrovandi GM, Wren TA, Gilsanz V. Brown adipose tissue and its relationship to bone structure in pediatric patients. Journal of Clinical Endocrinology and Metabolism. 2012;97(8):2693–8.