ESPE Abstracts

Background: Inhalation corticosteroids (ICS) as treatment for asthma can interfere with the hypothalamic-pituitary-adrenal axis and could lead to hypocortisolism. The frequency of this systemic side effect and the correlation to ICS usage is still unclear. Given that the cortisol excretion is pulsatile and determined by acute stress and circadian rhythms, the usefulness of tests based on momentary measures, such as saliva or serum are therefore limited. Cortisol levels measured in scalp hair provide a marker for long-term cortisol exposure and seems promising for diagnosing hypercortisolism.

Objective and hypotheses: The aim of this study is to determine the long-term hair cortisol concentrations (HCC) in children with asthma and corticosteroids usage compared to healthy controls.

Method: A case-control study was conducted at the Groene Hart Hospital, Gouda, 2014. All asthmatic children (4–18 years of age) using ICS for more than three months and visiting the general hospital were eligible as cases. Healthy controls were voluntarily enrolled children (4–18 years of age) from schools or from healthy siblings attending the pediatric outpatient clinic Erasmus MC, Rotterdam. Anthropometric characteristics and hair samples from the posterior vertex were obtained from cases and controls. HCC in three cm scalp hair was analyzed by Liquid chromotography-tandem mass spectrometry.

Results: 80 cases and 258 controls were enrolled for analysis. Median age of cases 10.8 (range: 4.1–17.6) and controls 11.5 (range: 4.3–18) were comparable (P=0.56). The use of budesonide equivalent dose by cases was 200–1 200 μg/day; with a median of 17.26 μg/kg (range 6.03–54.55) per day. Mean HCC-levels did not differ between cases and controls (F (1.336)=0.005, P=0.94) which did not change after adjusting for age, gender, height-SDS, and weight-SDS (F (1.332)=0.21, P=0.65). No correlation was found between budesonide doses and HCC levels.

Conclusion: Assessment of long-term cortisol levels by hair cortisol showed no difference in baseline adrenal function in children with asthma and ICS to their healthy controls. This study suggests that the HPA-axis dysfunction, found in adrenal stimulation tests in children with asthma on ICS may not lead to clinical relevant HPA-axis changes in day-to-day life.