Adrenal suppression in asthmatic children receiving low-dose inhaled budesonide: comparison between dry powder inhaler and pressurized metered-dose inhaler attached to a spacer

Evidence of hypothalamic-pituitary-adrenal axis suppression during moderate-to-high-dose inhaled corticosteroid use

The possible risk of adverse effects due to regular use of inhaled corticosteroids (ICS) is a real concern. Our aim was to describe the factors that have an impact on hypothalamic-pituitary-adrenal axis suppression (HPA-AS) in children and adolescents taking ICS regularly. The HPA axis status of patients who were on moderate-to-high-dose ICS [>176 and >264 μg/day fluticasone propionate-hydrofluoroalkane (FP-HFA) for patients 0-11 and ≥12 years, respectively] was investigated. Various types of ICS were converted to FP-HFA equivalent according to National Asthma Education and Prevention Program (NAEPP) guidelines. Participants with a baseline (8 a.m.) serum cortisol <15 μg/dL underwent a low-dose ACTH stimulation test (LDAT) to diagnose HPA-AS. Among 91 patients, 60 (75.9 %) participants underwent LDAT, and seven (7.7, 95 % CI 3.5-15.3 %) were diagnosed with HPA-AS. Ciclesonide was more frequently used by the participants with HPA-AS compared to patients with a normal HPA axis (42.9 vs. 4.8 %, p = 0.009). Use of ICS at moderate-to-high doses for at least 7 months distinguished participants with HPA-AS from those with a normal HPA axis. Among the duration, type, and dose of ICS, solely the use of ICS with a body mass index (BMI)-adjusted daily dose of ≥22 μg FP was found to increase the risk for HPA-AS (odds ratio (OR) 7.22, 95 % confidence interval (CI) 1.23-42.26, p = 0.028). The receiver operating characteristics (ROC) curve analysis revealed a cutoff value of 291 μg/day FP (area under the curve (AUC) = 0.840, p = 0.003) for predicting HPA-AS Conclusion: The prevalence of HPA-AS was found to be 7.7 % in children taking not only high-dose ICS but also moderate-dose ICS. Dose alone was found to be an actual risk factor for HPA-AS.

Impact of study design on the evaluation of inhaled and intranasal corticosteroids' effect on hypothalamic-pituitary-adrenal axis function

In part I of this review, an overview of the designs of hypothalamic-pituitary-adrenal (HPA) axis studies in the setting of inhaled corticosteroids (ICS) or intranasal corticosteroids (INS) use was discussed. Part II provides detailed discussion on the HPA axis evaluation results for each common ICS and INS, and how these results are possibly affected by the factors of study design. Significant adrenal suppression at conventional ICS/INS doses appears to be rare in clinical settings. The magnitude of cortisol suppression varies widely among different study designs. Factors potentially impacting this variability include: the choice of dose, dosing duration, assay sensitivity, statistical methodology, study population, and compliance. All of these factors have the potential to affect the extent of HPA axis effects detected and should be considered when designing or interpreting the results of a HPA axis study.

Impact of study design on the evaluation of inhaled and intranasal corticosteroids' effect on hypothalamic-pituitary-adrenal axis function, part I: general overview of HPA axis study design

Inhaled and intranasal corticosteroids (ICS and INS) are among the mainstays of the treatment for asthma and allergic rhinitis, respectively, and also carry the potential to suppress the hypothalamic-pituitary-adrenal (HPA) axis. Several important factors affect the interpretability of trials investigating the impact of ICS and INS on the HPA axis. This paper reviews 106 published clinical trials, peer-reviewed articles, and New Drug Application reviews of approved ICS and INS, using MEDLINE and Drugs@FDA database. The trials included in this review evaluated the potential impact on HPA axis function of eight approved single-ingredient ICS and INS (beclomethasone dipropionate, budesonide, ciclesonide, flunisolide, fluticasone furoate, flucticasone propionate, mometasone furoate, and triamcinolone acetonide) and combination products containing these ingredients. The most commonly utilized design was blinded, placebo controlled, and short term (<6 weeks) for adult trials and blinded, placebo controlled, and long term (≥6 weeks) for pediatric trials. Factors potentially affecting trial results include the choice of dose, dosing duration, assay sensitivity, statistical methodology, and the study population evaluated (patients or healthy volunteers). All of these factors have the potential to affect the level of adrenal suppression detected. In conclusion, to be informative, a HPA axis study should be well designed and carefully implemented to minimize variability in results and improve the overall interpretability of data obtained.

Once-daily ciclesonide via metered-dose inhaler: Similar efficacy and safety with or without a spacer

BACKGROUND

Inhaled corticosteroids (ICS) are recommended as first-line treatment for adults and children with persistent asthma. The Global Initiative for Asthma recommends that patients taking medium- or high-dose ICS delivered by metered-dose inhalers (MDIs) should use a spacer device.

METHODS

This randomized, open-label, 12-week, non-inferiority study compared the efficacy and safety of ciclesonide 160microg once daily delivered via hydrofluoroalkane-MDI alone (CIC160) or with a spacer (either an AeroChamber Plus [CIC160P] or an AeroChamber MAX [CIC160M]) in patients with persistent asthma. The primary efficacy variable was change in forced expiratory volume in 1s (FEV(1)) from baseline to study end.

RESULTS

Significant improvements in FEV(1) were observed from baseline to study end in each treatment group; least squares mean change from baseline ranged between 0.32 and 0.34L in the per-protocol (PP) analysis and similar results were observed for the intention-to-treat (ITT) analysis (p<0.0001 for all). Non-inferiority of CIC160P and CIC160M to CIC160 was observed for both PP and ITT populations (p<0.0001 [one-sided]). In all groups, daily asthma symptom scores were reduced to 0 and significant reductions were observed in rescue medication use at study end (p<0.0001 versus baseline for all). Ciclesonide was well tolerated in all groups and no cases of oral candidiasis were reported. Morning serum cortisol levels significantly increased in all groups from baseline to study end (p< or =0.0389), with no significant between-treatment differences.

CONCLUSION

In patients with persistent asthma, ciclesonide was shown to have similar efficacy and tolerability when administered via MDI alone or with a spacer.

Use of the low-dose corticotropin stimulation test for the monitoring of children with asthma treated with inhaled corticosteroids

OBJECTIVE

Subnormal hypothalamic-pituitary-adrenal (HPA) function and rare cases of adrenal crisis have been reported in asthmatic children treated with inhaled corticosteroids. We investigated subnormal HPA activity and followed up affected patients until recovery of normal HPA functions.

STUDY DESIGN

100 children with persistent asthma underwent low-dose corticotropin testing, with the administration of 1 microg of 1-24 ACTH intravenously. Treatments were beclomethasone dipropionate as a metered-dose inhaler, n = 14, budesonide as a dry-powder inhaler, n = 16, fluticasone propionate as a metered-dose inhaler n = 31 or a dry-powder inhaler n = 39. The mean commercially labelled dose was 520 +/- 29 microg/day (mean +/- SEM, range: 160-1,000) and the equipotent dose (which compares the efficiency of these drugs for treating asthma and their responsibility for systemic effects) was 890 +/- 55 microg/day (range: 200-2,000).

RESULTS

The mean stimulated cortisol level +/- SEM (and range) of the patient was 482 +/- 12 (148-801), and that of 40 age-matched controls was 580 +/- 12.5 (439-726), (SD = 79). The result was subnormal (more than 2 SD below the mean of the controls) in28 of the 100 patients. One-four stepwise decreases of 10-100% in the daily equipotent doses received by the patients with abnormal low-dose corticotropin testing results led to normal results in subsequent low-dose corticotropin testing in 27 retested patients. The mean time interval between two tests was 5 months (range: 2-6 months) and the mean period required for normalization of the test was 13 months (range: 2-21). Only one case of asthma exacerbation and no adrenal crisis were observed over these periods.

CONCLUSIONS

Decreasing daily equipotent doses led to recovery of normal HPA function without asthma exacerbation. Thus, a revision of the doses of inhaled corticosteroids used in asthmatic children with a progressive decrease to the consensus-recommended doses should decrease the systemic effects of inhaled corticosteroids, while minimizing the risk of asthma exacerbation.

Effects of mometasone furoate dry powder inhaler and beclomethasone dipropionate hydrofluoroalkane and chlorofluorocarbon on the hypothalamic-pituitary-adrenal axis in asthmatic subjects

STUDY OBJECTIVES

Mometasone furoate dry powder inhaler (MF-DPI) [400 mug] is an inhaled corticosteroid (ICS) that is effective in the treatment of asthma. MF-DPI has a low potential for suppression of the hypothalamic-pituitary-adrenal (HPA) axis at its clinical dose. The effect of MF-DPI, 400 microg qd, on the HPA axis was compared to that of beclomethasone dipropionate (BDP) using hydrofluoroalkane (HFA) and chlorofluorocarbon (CFC) propellants via metered-dose inhalers (MDIs) twice daily.

DESIGN AND INTERVENTIONS

This randomized, third-party blind, parallel-group study compared the effects of MF-DPI 400 mug one puff qd in the morning (n = 18), HFA-BDP 200 microg two puffs MDI bid (n = 18), and CFC-BDP 400 microg two puffs MDI bid (n = 17) for 14 days on the area under the 24-h serum cortisol concentrations curve (AUC(0-24)) and on total 24-h urinary free cortisol excretion in mild asthmatic subjects. Effects on morning/evening peak expiratory flow (PEF) and on inhaled albuterol use were also assessed. Adverse events that occurred during or > or = 30 days after the study were recorded.

RESULTS

The mean decrease from baseline in the serum cortisol concentrations AUC(0-24) in the MF-DPI group was significantly less than in either the HFA-BDP (p = 0.024) or the CFC-BDP (p = 0.011) groups. Decreases in serum cortisol concentrations AUC(0-24) in the two BDP groups did not differ from one another. The MF-DPI group trended toward higher morning and evening PEF than either BDP group. Treatment-associated adverse events were reported by seven subjects in the MF-DPI group, vs one subject in the HFA-BDP and three subjects in the CFC-BDP groups; these were mild, and no subject discontinued treatment due to an adverse event.

CONCLUSIONS

Fourteen days of treatment with MF-DPI 400 microg qd was associated with a significantly lesser decrease in the serum cortisol concentrations AUC(0-24) compared with HFA-BDP 200 microg MDI or CFC-BDP 400 microg MDI bid.

The effects of long term use of inhaled corticosteroids on linear growth, adrenal function and bone mineral density in children

In this study we aimed to investigate the long term effects of inhaled steroids on linear growth, adrenal function and bone mineral density. Thirty children with moderate asthma were randomly divided into two groups. Fifteen children (8 boys, 7 girls mean age; 10.6 +/- 2.1) were treated with budesonide (group 1), and 15 (9 boys, 6 girls, mean age; 9.6 +/- 2.4). with fluticasone propionate (group 2). Control group included 30 children. Anthropometric assessment, symptom and medication scores, pulmonary functions, bone mineral density, serum and urine cortisol levels and ACTH stimulation test were evaluated at the beginning of the study and after one year period. Symptom and medication scores, pulmonary functions improved significantly in both groups (p < 0.05). The mean annual growth was similar in group 1 and 2 and control group. Bone mineral density was comparable with control group at the beginning of the study and after one year. Mean serum cortisol level diminished at the end of the therapy but no significant differences were found between the initial and end values in respect to urine cortisol levels and cortisol/creatinine ratio. Of three groups ACTH stimulation test revealed that there were no significant difference between study and control groups. In conclusion, although we did not observed any side effects of inhaled corticosteroids we suggest that children treated with inhaled corticosteroids for a long time should be followed closely with respect to side effects.

Pharmacological Approach to Evaluate Aerosol Pulmonary Deposition

Drug delivery to the lung in vivo may be assessed using pharmacokinetic or pharmacodynamic techniques. The choice of method depends on drug class specificities. Pharmacokinetic determination of deposition to the lung for drugs without hepatic first-pass effect, such as short acting beta2-agonists, has to be done shortly after inhalation to minimize the effect of gastrointestinal absorption. For medication undergoing important hepatic first-pass metabolisation, such as inhaled corticosteroid, plasma concentration indirectly reflects bronchial deposition. The pharmacodynamic profile should be assessed through clinical effects and adverse events induced by inhaled drugs. Dose ranking of lung deposition for bronchodilators requires patient selection with sufficient bronchial obstruction to maintain room for improvement after the first dose. To assess dose effect relationship between inhaled corticosteroid, the Finney parallel line bioassay is the reference method with a study period of at least 6 weeks. Analysis of side effects with high doses of beta2-agonists or inhaled corticosteroids may also be used to compare lung deposition. Finally, pharmacological evaluation of lung deposition provides complementary information to scintigraphic studies, based on their clinical relevance.