Effect of inhaled budesonide on bronchial hyperresponsiveness in adolescents with clinical remission of asthma

Using thermal forced degradation approach for impurity profiling of budesonide solution-formulated metered dose inhalation with implementation of LC-QTOFMS and HPLC-UV

The impurity profile of budesonide solution-formulated metered dose inhalation using thermal forced degradation approach was studied intensively in this article. The structural identification of 10 budesonide related impurities was conducted by LC-QTOFMS, and the impurity level in the formulations of different excipients and packing materials were compared using HPLC-UV. Based on our results, the impurities were classified into three groups: (Ⅰ) process impurities, including budesonide impurity A, C and F; (Ⅱ) degradation products, including budesonide impurity E, G, D, 17-carboxylate, and 17-ketone; (Ⅲ) not only process impurities but also degradation products, including budesonide impurity I and L. Budesonide impurity D, 17-carboxylate, 17-ketone and impurity L were found to be the major degradation products of budesonide, and the reaction pathways for the generation of these impurities were speculated. The generation of budesonide impurity D, 17-carboxylate and L was found to be an aerobic oxidation process induced by Al₂O₃ on the inner surface of aluminum canisters. Furthermore, an in-depth discussion on the proposed impact of the excipients on budesonide degradation, especially on the Al₂O₃-induced oxidation process, was provided in this article.

Allergen challenge differentially affects the number of circulating monocyte subsets

Peripheral blood monocyte (PBM) subsets play different roles in inflammatory response and tissue remodelling. The aim of this study was to investigate how allergen challenge affects the number of circulating PBMs in Dermatophagoides pteronyssinus (Dp) allergic patients (Dp-APs). Among 34 Dp-APs challenged, in 22 patients significant bronchoconstriction was demonstrated [responders (Rs)], while in 12, only upper respiratory symptoms were seen [non-responders (NRs)]. Twelve healthy, non-atopic subjects were used as controls (HCs). Expression of CD14, CD16 and CCR4 was evaluated by flow cytometry on the whole-blood samples before (T(0) ), 6 h (T(6) ) and 24 h (T(24) ) after the challenge. Plasma concentrations of CCL2, CX3CL1 and CCL17 were evaluated using ELISA. At T(0) , the mean percentage of CD14++ CD16+ PBMs in Rs (35.4%; 95%CI 26.9-43.9%) was significantly greater than in HCs (14.6%; 95%CI 7.3-21.8%; P = 0.006) and in NRs (17.5%; 95%CI 9.6-25.4%; P = 0.001). The baseline number of CD14++ CD16+ PBMs correlated with airway hyper responsiveness (AHR) (r = -0.507; 95%CI -0.834 to -0.432, P < 0.001). At T(24) , the number of CD14++ CD16+ PBMs significantly decreased in Rs but not in NRs and the numbers inversely correlated with plasma CCL17 concentration. Changes in the number of circulating CD14++ CD16+ cells after Dp challenge correlated with AHR (r = 0.706, 95%CI 0.43-0.861; P < 0.001). In all subjects, the greatest expression of CCR4 was found on CD14++ CD16+ PBMs. Expansion of CD14++ CD16+ monocytes in the peripheral blood with subsequent mobilization of those cells after allergen challenge may facilitate the development of AHR in Dp-APs.

Effects of early measles on later rhinitis and bronchial hyperresponsiveness

BACKGROUND

The hygiene hypothesis suggests that infectious diseases in early life reduce the risk of allergic diseases.

OBJECTIVE

To investigate the association between measles infection during early childhood and the prevalence of allergic diseases, lung function, bronchial hyperresponsiveness (BHR), and sensitization in later childhood.

METHODS

A survey was conducted 5 years after a nationwide measles outbreak in Korea. From September 1 through November 30, 2006, we obtained information on history of measles and allergic diseases but not of measles vaccination through a questionnaire completed by 1004 schoolchildren aged 6 to 7 years. Furthermore, we measured measles antibody titers and performed skin prick tests, pulmonary function tests, and methacholine challenge tests. Children were divided into groups based on their history of measles infection and antibody titers.

RESULTS

Prevalence of measles infection was 8.2%. Children with both a positive measles history and a positive antimeasles antibody had significantly higher antimeasles antibody levels than those without a measles history. The prevalence of current rhinitis (adjusted odds ratio [aOR], 1.86; 95% confidence interval [CI], 1.02-3.40), rhinitis ever (aOR, 2.17; 95% CI, 1.19-3.94), and current BHR (aOR, 1.98; 95% CI, 1.04-3.78) was significantly higher in the group with a positive measles history compared with the group with a negative measles antibody. No differences were found among groups in the prevalence of asthma, lung function, provocation concentration that caused a decrease in forced expiratory volume of 1 second of 20%, or sensitization.

CONCLUSION

Early measles infection was associated with increased prevalence of rhinitis and BHR at the age of 7 years but has no effect on the development of asthma and allergy at the age of 7 years. This study indicates that common childhood infections such as measles in early age do not protect against later development of allergic diseases.

Sputum eosinophilia, airway hyperresponsiveness and airway narrowing in young adults with former asthma

BACKGROUND

30-80% of outgrown asthma subjects develop symptoms again later in life. We investigated inflammation and function of lower airway in adolescents with former asthma.

METHODS

326 never-smoking young adults (mean age 24.0 years) were interviewed with special emphasis on history of asthma. Diagnosis of asthma was based on GINA guidelines. Former asthma subjects consisted of ones with a history of physician-diagnosed childhood asthma, who had been free of asthma symptoms without the use of medication for at least 10 years prior to the study. Provocative concentration of methacholine causing a 20% fall in forced expiratory volume in 1 second (FEV(1))(PC(20)) and eosinophil percentage in induced sputum were measured.

RESULTS

31 subjects were former asthma subjects (FBA), 11 subjects were current asthma subjects (CBA) and 284 subjects had no history of asthma (non-BA). PC(20) and FEV(1)/FVC ratio were significantly lower in the FBA group than in the non-BA group (P < 0.01). Maximal mid-expiratory flow (MMF) was significantly lower in the FBA group than in the non-BA group (P < 0.05). Sputum eosinophil percentage was significantly increased in the FBA group compared with the non-BA group (P < 0.01). PC(20) was significantly lower in the CBA group than in the FBA and non-BA groups (P < 0.01). FEV(1), FEV(1)/FVC ratio and MMF were significantly lower in the CBA group than in the FBA group (P < 0.05, P < 0.05 and P < 0.05, respectively) and the non-BA group (P < 0.01, P < 0.01 and P < 0.05, respectively). Sputum eosinophils were significantly higher in the CBA group than in the FBA and non-BA groups (P < 0.01).

CONCLUSIONS

This study shows that subjects with long-term outgrown asthma continue to have airway eosinophilic inflammation, airway hyperresponsiveness and airway narrowing.

Predicting adult asthma in childhood

PURPOSE OF REVIEW

There still is no cure for asthma. Early identification of patients at risk for disease progression may lead to better treatment opportunities and hopefully better disease outcomes in adulthood. Recent literature on childhood risk factors associated with the outcome of asthma in adulthood is reviewed.

RECENT FINDINGS

The role of sex and smoking on the outcome of childhood asthma is still uncertain. Better lung function in childhood is consistently associated with better prognosis in adulthood, whereas the severity of bronchial hyperresponsiveness is not a good predictor of asthma outcome. Childhood atopy is associated with the persistence of symptoms but not with lung function in adulthood. An important finding is that anti-inflammatory treatment can reduce the accelerated decline in forced expiratory volume in 1 s and airway remodelling, but there is considerable variety in treatment response between individuals, which possibly can be explained by genetic make-up. Although many studies have investigated the genetics of asthma susceptibility, longitudinal studies on genes associated with asthma outcome are scarce.

SUMMARY

Despite many high-quality investigations, accurate prediction of adult asthma in childhood is still not feasible. Future studies should focus on associations between genetic background and asthma prognosis as an important area of research with great potential.

Peak expiratory flow variability and exercise responsiveness in methacholine-hyperresponsive adolescents with asthma remission

The aim of this study was to investigate whether bronchial hyperresponsiveness in adolescents with long-term asthma remission is associated with increased peak expiratory flow (PEF) variability and/or increased bronchial response to exercise (BRE). Twenty-nine adolescents with asthma remission (neither symptoms nor any medication used during the previous two years), but with persistent methacholine hyperresponsiveness (PC20 < 18 mg/mL; remission group), 29 methacholine PC20-matched adolescents with symptomatic asthma (symptomatic group), and 20 healthy subjects (control group) were studied. Subjects recorded PEF twice daily for 14 days and PEF variability, expressed as amplitude % mean, was calculated. Subjects also underwent a standardized exercise challenge; BRE was defined as a maximal % fall in FEV1 within 30 min after exercise. The mean (+/- SD) PEF variations in the symptomatic group and in the remission group were 12.10 +/- 6.35% and 10.02 +/- 4.73%, respectively, which were significantly higher than that (5.94 +/- 2.44%) of the control group. On the other hand, the degree of BRE (7.36 +/- 3.85%) in the remission group was significantly lower than that (22.31 +/- 10.50%) of the symptomatic group, and similar to that (5.98 +/- 2.70%) of the control group. Methacholine hyperresponsiveness in asthma remission during adolescence is associated with increased PEF variability but not with increased BRE.

Benefit from anti-inflammatory treatment during clinical remission of atopic asthma

STUDY OBJECTIVES

Subjects with atopic asthma often experience a disappearance of symptoms around puberty. However, airway inflammation and remodeling may persist. It is unknown whether those findings warrant prolonged anti-inflammatory treatment despite the absence of symptoms. In this study, we investigated whether a short course of combined anti-inflammatory treatment would, also in this specific patient population, diminish airway inflammation and/or remodeling.

DESIGN

A double-blind, randomized placebo-controlled trial was conducted in 28 asymptomatic subjects with a history of atopic asthma, with established bronchial hyperresponsiveness to methacholine (MCh) as non-invasive indicator of ongoing airway pathology.

INTERVENTIONS

Intervention consisted of the salmeterol/fluticasone propionate combination (SFC) product (50/250 microg bid via the Diskus inhaler) or placebo for 3 months.

MEASUREMENTS

The change in lung function (FEV1), bronchial response to MCh and adenosine monophosphate (AMP), the fraction of nitric oxide in exhaled air (FENO) and quality of life (QOL) scores were measured. Also, bronchial biopsies were taken and cryo sections immunostained for eosinophils (major basic protein, MBP) and mast cells (tryptase and chymase) before and after treatment. The change in reticular basement membrane (RBM) thickness, one of the parameters of airway remodeling, was also determined.

RESULTS

SFC treatment improved hyperresponsiveness to MCh (P = 0.014) as well as AMP (P = 0.011), and reduced FENO (P < 0.001) significantly as compared with placebo. Lung function tended to improve (NS). Furthermore, SFC treatment reduced tryptase in the subepithelium of bronchial biopsy specimens (P = 0.01), and slightly reduced RBM thickness (P = 0.05). However, eosinophils in (sub)epithelium were not significantly affected; neither were chymase levels, blood eosinophils or QOL scores.

CONCLUSIONS

We found that 3 months of treatment with fluticasone propionate and salmeterol reduced airway hyperresponsiveness, FENO and tryptase density in the airway mucosa as markers of airway inflammation. MBP density in the airway mucosa and QOL were, however, unchanged. The clinical relevance of these findings, especially with respect to the long-term outcome, has not been determined yet.

Absence of association of peripheral blood eosinophilia or increased eosinophil cationic protein with bronchial hyperresponsiveness during asthma remission

BACKGROUND

The mechanisms responsible for persistent bronchial hyperresponsiveness (BHR) in adolescents with long-term asthma remission are poorly understood.

OBJECTIVE

To determine whether BHR in adolescents with asthma remission is associated with peripheral blood eosinophilia, increased serum levels of eosinophil cationic protein (ECP), or both findings.

METHODS

We classified 51 adolescents with long-term asthma remission (neither asthma-related symptoms nor medication during the previous 2 years) into 28 BHR-positive patients (methacholine PC20 [provocative concentration causing a 20% decrease in forced expiratory volume in 1 second] <18 mg/mL) and 23 BHR-negative patients. The peripheral blood eosinophil counts and serum ECP concentrations were compared between these 2 groups. Twenty-eight patients with symptomatic asthma (symptomatic group), matched for methacholine PC20 level with study subjects in the BHR-positive remission group, and 28 healthy adolescents (control group) were also studied.

RESULTS

No significant differences in the peripheral blood eosinophil counts (262.1 +/- 117.0/microL vs 253.9 +/- 165.0/microL) and the serum ECP levels (15.6 +/- 10.0 microg/L vs 15.8 +/- 11.9 microg/L) were found between the BHR-positive and BHR-negative remission groups, respectively. The BHR-positive remission group differed from the symptomatic group (372.9 +/- 190.3/microL, P < 0.05; 26.6 +/- 11.3 microg/L, P < 0.01) in both blood indices but resembled the control group (214.6 +/- 118.6/microL and 12.1 +/- 4.8 microg/L; both, no significant difference).

CONCLUSIONS

BHR in adolescents with long-term asthma remission is not associated with peripheral blood eosinophilia or an increase in serum ECP concentration. This finding suggests that the mechanism underlying BHR in this clinical setting may differ from that in symptomatic asthma.

Bronchial hyperresponsiveness in adolescents with long-term asthma remission: importance of a Family history of bronchial hyperresponsiveness

BACKGROUND

The mechanisms responsible for bronchial hyperresponsiveness (BHR) in symptomatic asthma include genetic predisposition and airway inflammation, but the causes of BHR in adolescents with asthma remission are poorly understood. It has been shown that BHR in adolescents with asthma remission was not reduced by prolonged treatment with inhaled corticosteroids, in contrast to the BHR of symptomatic asthma.

OBJECTIVE

The aim of this study was to investigate whether family history of BHR may contribute to the persistence of BHR in asthma remission during adolescence.

METHODS

One hundred twenty-six adolescents with long-term asthma remission (neither symptoms nor any medication used during the previous 2 years) and their parents underwent a methacholine inhalation test. The provocative concentration of methacholine causing a 20% fall in FEV(1) (PC(20)) and the bronchial responsiveness (BR) index were calculated for each individual.

RESULTS

Sixty-nine adolescents (54.8%) were found to have persisting BHR (PC(20) < 18 mg/mL). The frequency of BHR and the BR index were significantly higher in parents (n = 138) of the BHR-persisting group (28.3% and 1.150 +/- 0.103, respectively [mean +/- 1 SD]) than in parents (n = 114) of BHR-nonpersisting group (16.7% [p = 0.030] and 1.124 +/- 0.088 [p = 0.029], respectively). Furthermore, adolescents (n = 56) with at least one BHR-positive parent were found to have a higher frequency of BHR (66.1% vs 45.7%, p = 0.023) and a higher BR index (1.244 +/- 0.090 vs 1.204 +/- 0.082, p = 0.011) than adolescents (n = 70) with non-BHR parents.

CONCLUSION

Our results suggest that adolescents in asthma remission are more likely to have BHR when there is a family history of BHR. Further studies are needed to examine the possible involvement of genetic factors in the BHR of adolescents in asthma remission.

8. Occupational asthma and allergies

A diversity of airborne dusts, gases, fumes, and vapors can cause dose-related symptoms in individuals exposed in the workplace. More than 250 chemicals have been incriminated as a cause of occupational asthma (OA). The prevalence of OA ranges from 2% to 6% of the asthmatic population. Predisposing factors facilitating the development of OA include the work environment, climatic conditions, genetic proclivities, tobacco and recreational drug use, respiratory infection, and bronchial hyperresponsiveness. Pathogenetically, new-onset OA may be immunologic or nonimmunologic in origin. The immunologic variants are usually caused by high molecular-weight allergens such as grain dust and animal or fish protein. Symptoms ensue after a latent period of months to years. Nonimmunologic OA can be precipitated by a brief, high-level exposure to a potent irritant. Symptoms occur immediately or within a few hours of the exposure. In either instance, once the diagnosis is established, the worker should be removed from the workplace. If the diagnosis is made in a timely fashion, most workers experience improvement. Prevention is the best therapeutic intervention.

Maximal airway response in adolescents with long-term asthma remission and persisting airway hypersensitivity: its profile and the effect of inhaled corticosteroids

BACKGROUND

Many children with asthma go into long-term clinical remission at adolescence, but bronchial hyperresponsiveness (BHR) persists in some of these subjects. BHR in asthma is characterized by an increase in sensitivity and in maximal airway response to bronchoconstrictor stimuli.

OBJECTIVE

The aims of this study were to compare the profiles of maximal airway response between adolescents with asthma remission and adolescents with symptomatic asthma to a similar degree of airway hypersensitivity, and to determine whether maximal airway response in adolescents with asthma remission is reduced by prolonged treatment with inhaled corticosteroids.

METHODS

A high-dose methacholine inhalation test was performed in 46 adolescents with long-term asthma remission (remission group) and 44 adolescents with symptomatic asthma (symptomatic group). Subjects exhibiting a maximal response plateau in the remission group were administered inhaled budesonide (400 microg bid, budesonide/remission group, n = 15) or identical placebo (placebo/remission group, n = 15) for 6 months, and the subjects in the symptomatic group were administered the same regimen of budesonide (budesonide/symptomatic group, n = 17). The plateau level was measured after 3 months and 6 months of treatment.

RESULTS

Thirty-four subjects (73.9%) in the remission group featured a maximal response plateau on the dose-response curve to methacholine, whereas 19 subjects (43.2%) in the symptomatic group had a plateau (p = 0.003). In neither the placebo/remission group nor the budesonide/remission group did the plateau level change significantly over the 6-month period, whereas budesonide markedly decreased the level in the budesonide/symptomatic group.

CONCLUSION

The difference in frequency of detection of a plateau between the remission group and the symptomatic group, as well as the difference in its response to treatment with budesonide between the two groups, suggests that inflammatory changes impact the maximal airway response in symptomatic asthmatic adolescents but not in adolescents with asthma remission.