Background: The ability to respond to stress constitutes a defensive protective mechanism; both inadequate and excessive responses may be detrimental.
Objective and hypotheses: To investigate the effect of increased body weight on the hormonal response to stress in children. Scheduled surgical procedures include two stressful parts, a psychological one (anticipation of operation) and a biological one (surgical stress per se) and were chosen as a study model.
Method: A total of 30 children, scheduled for minor surgical procedures (hernia, orcheopexy) and well otherwise, were included in the study. Two groups were studied: obese (O) group (15 children, aged 5±2 years, BMI-z score: 9.5±1.9) and normal weight (N) group (15 children, aged 4±2, BMI-z score: 1.7±1.5). Blood samples were obtained prior to any manipulation (P1), after anaesthesia induction (P2), during surgery (P3) and one hour after the end of surgery (P4).
Results: Prolactin was similarly increased at P1 in both groups and gradually fell in the N group, whereas stayed unchanged throughout in the O group (P=0.005 at P4 between groups). GH was significantly lower in the O than the N group at start (P1 and P2, P<0,001). T4 was significantly higher in the N than the O group at P2 and P3 (P<0.001) combined with an inadequate TSH and T4 rise in the O group. Cortisol was significantly higher in the N compared to the O group at P1 and P2 (P<001). Interestingly, cortisol in the N group peaked at P2, whereas in the O group peaked at P4. ACTH did not differ between the two groups, however, the cortisol/ACTH ratio was significantly lower in the O than in the N group (P=0.01) throughout sampling.
Conclusion: Timing and intensity of the endocrine stress response differs between obese and normal weight children. The biological mechanisms involved are not apparent but may reflect an insufficient response to environmental stressors in obese children.
10 - 12 Sep 2016
European Society for Paediatric Endocrinology