Circadian Cortisol Rhythms in Healthy Boys and Girls: Relationship with Age, Growth, Body Composition, and Pubertal Development¹

Abstract

To provide basic information on the normal functioning of the hypothalamus-pituitary-adrenal axis in relation to pubertal development, growth (weight and height), body composition, and gender and to obtain reference data for serum cortisol concentrations in children, we investigated the basal circadian rhythm of serum cortisol in a group of 235 healthy children (162 boys and 73 girls). The age range was between 2.2-18.5 yr. Serum cortisol was analyzed from venous blood samples taken at 1400, 1800, 2200, 0200, 0400, 0600, and 1000 h. No evidence was found for differences in temporal placement or level of the circadian cortisol rhythm in relation to age, growth, or body composition. However, we found a broad range of cortisol levels in a healthy population, with individual mean diurnal levels ranging from 100-510 nmol/L. Regardless of high or low mean diurnal cortisol levels, repeated measurements within and between pubertal stages indicated that an individual remains in his or her cortisol range throughout pubertal development. In conclusion, the present study shows that 1) serum cortisol levels do not correlate with either age or gender; 2) there is a large and significant interindividual variability in endogenous mean diurnal cortisol levels; and 3) despite this variability between individuals, there is no correlation between cortisol levels and either body composition or growth rate. This suggests that the variability in cortisol levels is an expression of normal homeostasis rather than pathology.

Responses of Lipolysis and Salivary Cortisol to Food Intake and Physical Activity in Lean and Obese Children

“…In the present study the salivary cortisol concentrations of both groups tended to follow previously reported diurnal variation (35,36), indicating normally functioning HPA axes. Salivary cortisol concentrations in the LN and OB groups were highest in the morning, reached low points in the early afternoon (1200 -1300 h), and rose in response to lunch.…”

Validation and Reference Ranges of Hair Cortisol Measurement in Healthy Children

“…serum or saliva, the relation between age and cortisol concentrations has yielded conflicting results. Knutsson et al [12] found no effects of age on serum cortisol in a study in 235 healthy children. However, two larger studies on serum cortisol in 762 and 1,482 healthy children aged 0-18, respectively, reported high cortisol variance in neonates and infants, after which cortisol rapidly decreased to subsequently increase steadily with age up to adulthood [13,14].…”

Diurnal Salivary Cortisol Concentration in School-aged Children: Increased Morning Cortisol Concentration and Total Cortisol Concentration Negatively Correlated to Body Mass Index in Children with Recurrent Abdominal Pain of Psychosomatic Origin

“…Mean (range) age was 10.8 (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18) years. The criteria for this diagnosis are exclusion of an organic cause and fulfilling six out of the following seven criteria: 1. onset or aggravation of chronic negative stress at the time of onset of recurrent pain; 2. pain in parallel with chronic negative stress; 3. feeling better or pain-free during periods of lessened/no chronic negative stress; 4. pain induced by acute stress"; 5. most pain attacks related to acute stress; 6. the child followed up for at least 1 year; 7. parent/child and responsible doctor agree about the diagnosis 5 .…”