Growth and adrenal responsiveness with budesonide in young asthmatics

Nebulized fluticasone propionate, a viable alternative to systemic route in the management of childhood moderate asthma attack: A double-blind, double-dummy study

BACKGROUND

In this study, we compared the clinical and immunological efficacy of nebulized corticosteroid (CS) to systemic route during treatment of moderate asthma attack in children.

METHODS

In this randomized, placebo-controlled, double-blind, double-dummy, prospective study, 81 children aged 12 months to 16 years experiencing asthma attack randomized into two treatment groups to receive, either; nebulized fluticasone propionate (n = 39, 2000 mcg/day) or oral methylprednisolone (n = 41, 1 mg/kg/day). Pulmonary index scores (PIS) were assessed at admission and at 1st, 4th, 8th, 12th, 24th, 48th hours, as well as, on day 7 and peak expiratory flow (PEF) at baseline and at the 7th day. Daily symptom and medication scores were recorded for all subjects. Immunological studies included phytohemagglutinin induced peripheral blood mononuclear cells culture supernatant for cytokine responses and CD4(+) CD25(+) FOXP3(+) T regulatory cell (T reg) percentage at baseline and day 7.

RESULTS

The changes in PIS and PEF were similar in both treatment groups, with a significant improvement in both values at the 7th day, when compared to baseline. In both groups, significant reductions in symptom and medication scores were observed during the treatment period with no significant difference between the groups. At day 7 of intervention, phytohemagglutinin induced IL-4 level was significantly decreased only in the nebulized group compared to baseline (p = 0.01). Evaluation of cytokine responses by means of fold increase (stimulated (S)/unstimulated (US) ratio) revealed a significant reduction in IL-4, IL-5 and IL-17 only in nebulized group (p = 0.01, 0.01, 0.02; respectively). The fold increase value of IL-5 was significantly lower at 7th day in nebulized group when compared to systemic one (p = 0.02). At 7th day, although in both treatment groups the percentage of T reg cells was suppressed, it remained significantly higher in the nebule one when compared to systemic route (p = 0.04).

CONCLUSION

In the management of moderate acute asthma attack, nebulized CS (2000 mcg daily) was found to be as effective as systemic route with regard to clinical improvement. In addition, immunological parameters were more in favor of nebulized route which may imply a salutary effect of local CS usage.

Impact of inhaled and intranasal corticosteroids on the growth of children

Since inhaled and intranasal corticosteroids may be systemically bioavailable, risk of growth suppression cannot be ruled out in children treated with these compounds. The mechanisms by which exogenous corticosteroids can cause growth suppression may be multifactorial, involving influences on growth hormone secretory profiles and insulin-like growth factor-I activity, direct effects on the epiphyseal growth plate, and effects on bone and collagen turnover. When studies on growth in children treated with inhaled and intranasal corticosteroids are interpreted, it is important to discriminate between data on the final outcome of growth (adult height) and data on growth rate. No firm conclusions can be drawn on adult height from the available data. While the data on children treated with inhaled corticosteroids appear reassuring, there are no peer-reviewed studies on the final height of children treated with intranasal corticosteroids. The possibility of additive effects on the final height or growth rate of children receiving intranasal plus inhaled corticosteroids has also not been studied. When assessing the risk of growth rate suppression, specific corticosteroids, doses and inhaler systems must be evaluated separately. Standard paediatric doses of inhaled corticosteroids (budesonide 200 to 400 microg/day delivered from a metered dose inhaler with a spacer, dry powder budesonide 200 microg/day, or dry powder fluticasone propionate 200 microg/day) do not affect growth rate when a twice daily administration regimen is used. The risk of growth rate suppression in children treated with inhaled budesonide depends on the dosage and may become significant with 800 microg/day administered with a spacer, or with 400 microg/day administered with a dry powder device. When high doses of inhaled corticosteroids are used, the risk of adverse effects on growth rate can be reduced by once daily dosage in the morning. In fact, intranasal mometasone furoate 100 and 200microg from an aqueous pump spray and dry powder budesonide 200 and 400microg once daily in the morning have been found not to affect growth rate. Sensitivity to adverse effects on growth rate may vary between individuals. If growth suppression is detected, 'catch-up growth' may be expected when the dose of the inhaled or intranasal corticosteroid is reduced or other treatment modalities are introduced. Inhaled or intranasal corticosteroids should not be withheld from children with asthma or rhinitis. Topical corticosteroids should be given in doses that control disease symptoms; however, height measurements should be performed regularly in children receiving corticosteroids.

Asthma

Asthma has been recognized as a disease since the earliest times. In the Corpus Hippocraticum, Hippocrates used the term “ασθμα” to indicate any form of breathing difficulty manifesting itself by panting. Aretaeus of Cappadocia, a well-known Greek physician (second century A.D.), is credited with providing the first detailed description of an asthma attack [13], and to Celsus it was a disease with wheezing and noisy, violent breathing. In the history of Rome, we find many members of the Julio-Claudian family affected with probable atopic respiratory disorders: Caesar Augustus suffered from bronchoconstriction, seasonal rhinitis as well as a highly pruritic skin disease. Claudius suffered from rhinoconjunctivitis and Britannicus was allergic to horse dander [529]. Maimonides (1136–1204) warned that to neglect treatment of asthma could prove fatal, whereas until the 19th century, European scholars defined it as “nervous asthma,” a term that was given to mean a defect of conductivity of the ninth pair of cranial nerves.

Concerns about intranasal corticosteroids for over-the-counter use: position statement of the Joint Task Force for the American Academy of Allergy, Asthma and Immunology and the American College of Allergy, Asthma and Immunology

The Joint Task Force for the American Academy of Allergy, Asthma and Immunology and the American College of Allergy, Asthma and Immunology was charged with formulating a position paper regarding the potential release of intranasal corticosteroids for over-the-counter use. We took the position that safety issues regarding this proposal would be our sole concern. We reviewed the literature to evaluate the frequency and severity of potential adverse events related to the administration of intranasal corticosteroids. We limited this review to 5 areas: (1) effects on growth, (2) ocular effects, (3) effects on bone, (4) effects on the hypothalamic-pituitary-adrenal axis, and (5) local adverse effects. After review of the available data, we concluded that intranasal corticosteroids should remain prescription-only drugs. Patients receiving an intranasal corticosteroid should be instructed in its use and that use should be monitored by a physician or an appropriately trained medical provider (eg, nurse practitioner or physician assistant) under the direct supervision of a physician. This conclusion was reached based on the evidence that corticosteroids administered by any route, including the intranasal route, have the potential to cause adverse effects in all the areas noted herein. Our conclusion was strengthened by the fact that these adverse effects can be insidious and therefore not evident for many years; there is the potential for overuse; patients could also have access to other forms of topically administered corticosteroids, thus increasing their total dose; and individuals vary in their susceptibility to corticosteroid-induced adverse effects. We were also influenced to take this position knowing that generally reassuring data regarding the use of respiratory tract-administered corticosteroids are based on mean data and that all such studies have shown outliers in whom adverse effects were evident. Thus, as stated, we recommend that intranasal corticosteroids remain prescription-only drugs.

Long-term outcomes in paediatric asthma

Over the years the aims of asthma management have changed markedly from effective prednisolone treatment of symptoms and exacerbations towards more use of continuous prophylactic treatment. With our new understanding of the disease and its management definition of the aims of treatment and assessment of optimal asthma control have become much more complex. Even in times of evidence-based medicine our asthma management is based upon findings of effects on various outcomes in somewhat short-term (<1 year) controlled studies. However, assumptions about long-term effects upon the basis of findings in such studies should be made with great caution. Good examples of this are studies which assess the risk of systemic effects and clinical adverse effects of inhaled corticosteroids. From such studies it has become clear that systemic effects detected in short-term trials may have no predictive value of long-term adverse effects. Thus steroid-induced changes in lower leg growth rates assessed by knemometry do not predict long-term statural growth. Moreover, steroid-induced changes in statural growth over 1 year are not predictive of effects upon attained adult height. In contrast, reduced growth caused by uncontrolled asthma disease also seems to affect attained adult height adversely. These findings suggest that long-term outcomes should play a larger role when future asthma management strategies are decided. Some important long-term outcomes of asthma management in children include cure or remission of the disease, prevention of complications of the disease (airway remodelling, adverse effects upon growth/adult height, peak bone mineral density, physical impairment and psychosocial development) or its pharmacological management (adverse effects upon adult height, peak bone mineral density). More controlled long-term studies (several years) are needed to provide a better understanding of how these outcomes are best achieved.

Inhaled steroids and the risk of adrenal suppression in children

Corticosteroids are the mainstay of treatment of all asthma severity levels in adults and children. With their widespread use comes a responsibility to monitor, understand, and balance their efficacy and safety. Systemic adverse effects such as adrenal suppression have been clearly associated with the use of oral corticosteroids and to a lesser degree with the use of inhaled corticosteroids (ICS). In clinical trials, adrenal suppression is more evident when ICS are used in long-term therapy and at higher doses. However, monitoring adrenal suppression during short-term therapy and at lower doses is still of value in order to ascertain the lower limit of an inhaled corticosteroid's safety profile. Significant adrenal suppression at conventional ICS doses appears to be rare in clinical practice. When evaluating the effect of ICS on the hypothalamo-pituitary-adrenal-axis (HPA-axis), one must consider sources of variability both within and among trials including test sensitivity, systemic bioavailability, degree of airway obstruction, and delivery devices. All of these factors have the potential to effect the level of adrenal suppression detected and must be considered when interpreting HPA-axis test results in research or practice. This review will discuss adrenal suppression found with common ICS.

Safety of inhaled corticosteroid therapy in young children with asthma

BACKGROUND

Physicians have had some reluctance to use inhaled corticosteroids in very young children with asthma because of the possible risks of adverse systemic effects.

OBJECTIVE

The purpose of this study was to evaluate the effects of fluticasone propionate on growth and adrenocortical function in young children with asthma.

METHODS

We performed an open, prospective study for 24 weeks of 20 children with asthma, 2.5 to 5.0 years of age, who had received fluticasone by a large volume spacer at dosages ranging from 190.50 to 565.40 microg/m2 daily. Growth was evaluated by height standard deviation scores measured by a stadiometer. Adrenocortical function was evaluated twice in each child, before and after the study, by determining fasting serum cortisol concentrations at 8 AM and also at 30 and 60 minutes after adrenocorticotropic hormone stimulation. Posttreatment values of height standard deviation scores and fasting morning serum cortisol concentrations were compared with those of 18 age-matched children, who constituted the control group.

RESULTS

The evaluation of mean +/- SEM (and range) of height standard deviation scores revealed a significant decrease from 0.44 +/- 0.27 (-1.46 to 2.22) to 0.28 +/- 0.26 (-1.51 to 2.07; P = 0.01) at week 18 and to 0.25 +/- 0.24 (-1.90 to 2.13; P = 0.04) at the week 24 in fluticasone-treated children. At the end of the treatment, however, height standard deviation scores of these children did not differ significantly (P = 0.35) from those of the control group. Delayed growth with medium-duration treatment was not associated with alterations in serum cortisol measurements, either at baseline or after stimulation. The mean fasting morning serum cortisol concentrations did not differ significantly between the fluticasone-treated patients and the control group.

CONCLUSIONS

Some concern prevails about the safety of medium- or long-term treatment with regularly inhaled corticosteroids in young children with asthma. The prepubertal growth may be delayed, but the effect on ultimate height remains uncertain in such children. Growth should be regularly monitored in children who begin inhaled corticosteroid therapy for mild persistent asthma at an age <5 years old.

Measures of hypothalamic-pituitary-adrenal function in patients with asthma treated with inhaled glucocorticoids: clinical and research implications

In asthmatic patients treated with inhaled glucocorticoids there may be a risk of suppression of hypothalamic-pituitary-adrenal (HPA) function. The aim of the present study was to review peer-refereed data on HPA function in asthmatic patients taking inhaled glucocorticoids, and to discuss the value of HPA function measures in clinical practice and research. There is no evidence that inhaled glucocorticoids in recommended doses cause clinically significant HPA insufficiency. If sensitive measures of basal adrenal activity are used, however, dose-related suppressive effects with specific drugs and application systems can be detected. In adults, fluticasone propionate appears to be more potent than budesonide or triamcinolone acetonide in suppressing measures of basal adrenal activity. Measures of basal adrenal activity are useful in clinical trials that assess and compare systemic activity of specific drugs, application devices, and administration regimens, but have no place in the management of asthma.

Linear growth of very young asthmatic children treated with high-dose nebulized budesonide

The aim of this open study was to observe linear growth in young children with asthma treated with nebulized budesonide. Infants and young children (< 3 years old) with severe uncontrolled asthma were studied. They were treated with nebulized budesonide (1-4 mg day-1) and treated for at least 6 months. Height standard deviation scores (HtSDS) were measured before ("pre-measurements") immediately prior to commencing nebulized budesonide therapy (baseline) and after at least 6 months of therapy ("post-measurements"). The mean HtSDS score at pretreatment was -0.21 and at baseline had fallen further to -0.46. The mean HtSDS increased to -0.17 when the post-measurements were made (p = 0.035) after at least 6 months of nebulized budesonide therapy. Treatment with nebulized budesonide for longer than 6 months in very young children with severe asthma was not associated with reduced linear growth.

The use of inhaled steroids in young children

There are apparently irreversible inflammatory changes in the airways of young adults with chronic asthma so a strong case can be made for starting anti-inflammatory treatment early. Corticosteroids have potent and diverse anti-inflammatory activity. High efficacy is established in school age children. Trials in pre-school children and infants have given more mixed results perhaps because of problems with administration. No clinically important systemic effects have been observed in children taking conventional doses of inhaled steroids.