To the Editor:
We read with great interest the paper by Sim et al. 1 who observed adrenal suppression from high-dose inhaled fluticasone propionate (FP) in children with asthma. As adrenal inhibition has also been reported to occur with moderate doses of inhaled FP 2, we recently addressed the question whether low-dose (100 µg twice daily) FP could be associated with impaired adrenal function. For this purpose, 25 children (16 males/9 females) aged 2–12 yrs (mean±sd 5.78±3.1 yrs) were recruited. All children were affected by moderate asthma and treated with inhaled FP with spacer device for up to 3 months. Early morning cortisol and adrenocorticotrophic hormone (ACTH) levels were determined at the beginning and at the end of the treatment period, after inhalatory therapy had been withdrawn for ≥24 h. Serum cortisol and ACTH levels were measured by commercially available radioimmunoassay. Data were analysed by paired t-testing and Pearson correlation coefficient. Cortisol levels were significantly higher at the beginning of the treatment period (449±158.3 nmol·L−1) when compared to the end of therapy (377.4±110.8 nmol·L−1; p=0.01); one patient presented cortisol levels compatible with complete adrenal suppression (131.8 nmol·L−1) This was associated with significantly higher levels of ACTH at the end of therapy (36.5±4.3 versus 28.3±9.5 pg·mL−1; p=0.01). No correlation could be found between age and adrenal dysfunction (p=0.09). The combination of low early morning cortisol levels and high ACTH levels at the end of FP therapy, having withdrawn the inhaled corticosteroid therapy for at 24 h, is highly suspicious of adrenal suppression during treatment with prompt, but partially recovery of the pituitary-adrenal axis once therapy is stopped. Despite the large extent of the adrenal dysfunction, none of the children showed clinical symptoms of adrenal suppression. However, this phenomena might lead to decreased adrenal response to stress and infections, and should therefore not be underestimated 3.
In conclusion, with reference to the important message of Sim et al. 1 on a significant interference with the pituitary-adrenal axis of high-dose fluticasone propionate, clinicians should be aware of the possibility of adrenal impairment even with low-dose fluticasone propionate, as this has important implications not only for the management of intercurrent illnesses but also on the way of tapering the inhalatory therapy as previously suggested 4.
- © ERS Journals Ltd