Bronchial hyperreactivity and spirometric impairment in patients with perennial allergic rhinitis

BACKGROUND: Allergic disorders are characterized by a systemic involvement of the immune response. There is a clear link between allergic rhinitis and asthma. Bronchial hyperreactivity (BHR) may be present in rhinitics. Smaller airways may also be impaired in mild asthma. This study aimed at evaluating a group of subjects suffering from perennial allergic rhinitis alone to investigate the presence of BHR and spirometric impairment. METHODS: One hundred rhinitics sensitized only to perennial allergens were evaluated. Spirometry and methacholine bronchial challenge were performed. RESULTS: Five rhinitics showed reduced values of forced expiratory volume/1 s (FEV(1)) without symptoms of asthma. Forty-eight rhinitics had reduced forced expiratory flow at 25 and 75% of pulmonary volume (FEF(25-75)) values. Seventy-two patients showed a positive methacholine challenge. In this group, reduced values of FVC (p < 0.05), FEV(1) (p < 0.05), and FEF(25-75) (p < 0.01) were demonstrated in comparison with BHR-negative rhinitics. There was a relationship between the degree of BHR and FEV(1) values (p < 0.05) and FEF(25-75) values (p < 0.01). CONCLUSIONS: This study evidences that an impairment of spirometric parameters may be observed in patients with perennial allergic rhinitis alone. A high percentage of these patients have BHR. Thus, new management strategies should be employed in rhinitics.     

Impact of allergic rhinitis on asthma: effects on bronchial hyperreactivity

Background:  Remarkable relationship exists between upper and lower airways. Bronchial hyperreactivity (BHR) is a paramount feature of asthma and may be considered a strong risk factor for the onset of asthma in patients with allergic rhinitis.
Objective:  This study is aimed at evaluating the presence of BHR in a large group of patients with moderate-severe persistent allergic rhinitis alone, and at investigating possible risk factors related to severe BHR.
Methods:  Three hundred and forty-two patients with moderate-severe persistent allergic rhinitis were prospectively and consecutively evaluated. Clinical examination, skin prick test, spirometry and bronchial methacholine (MCH) test were performed in all patients.
Results:  Twenty-two (6.4%) patients had severe BHR, 74 (21.6%) patients had mild BHR and 192 (56.2%) had borderline BHR; 54 (15.8%) patients had a negative MCH test. The logistic regression analysis evidenced that trees and house dust mites sensitization (OR_Adj: 8.1), rhinitis duration > 5 years (OR_Adj: 5.4) and FEV₁ ≤ 86% of predicted (OR_Adj: 4.0) were significantly associated with severe BHR. The discriminative ability of this model is appreciably satisfactory, being the AUC = 0.90.
Conclusion:  This study highlights the close link between upper and lower airways and the role of some risk factors, such as tree and mite sensitization, > 5-year duration, and ≤ 86% FEV₁ values, as risk factors for severe BHR in patients with moderate-severe persistent allergic rhinitis alone. Therefore, BHR is frequently present in patients with chronic rhinitis and should be suspected in the presence of defined risk factors.     

Nasal inflammation and bronchial reactivity to methacholine in atopic children with respiratory symptoms

BACKGROUND: In atopic subjects, dysfunctions of the upper and lower airways frequently coexist and allergic rhinitis seems to constitute a risk factor for the occurrence of asthma in predisposed individuals. AIM OF THE STUDY: To evaluate whether in atopic subjects nasal inflammation could reflect changes in respiratory functions, 11 allergic children, sensitized to house dust mites (HDM), with rhinoconjunctivitis and asthma and 10 nonatopic controls (ctrs) were studied. METHODS: All subjects underwent nasal brushing to detect percentages of nasal eosinophils (Eos %) and intercellular adhesion molecule-1 (ICAM-1) expression by nasal epithelial cells. In the same day pulmonary function tests, i.e. forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), forced expiratory flows at 25-75% of the vital capacity (FEF25-75%) and methacholine (MCh) bronchial inhalation challenge were also evaluated. RESULTS: Pulmonary function parameters were not significantly different in allergic children and in ctrs (P > 0.05), while a significant increase in bronchial reactivity to MCh, expressed as Pd20 MCh, was detected in the former population (P < 0.05). As compared with ctrs, allergic children showed elevated Eos % and ICAM-1 expression (P < 0.05). When nasal inflammation and pulmonary function parameters were compared, a significant correlation was found between nasal Eos % and bronchial reactivity to MCh (P = 0.002). CONCLUSIONS: These data support the concept of significant links between upper and lower respiratory tract involvement in atopic children sensitized to HDM.     

Comparison of deltaFVC between patients with allergic rhinitis with airway hypersensitivity and patients with mild asthma.

BACKGROUND: In asthmatic individuals, airway sensitivity and maximal airway response are increased. Airway sensitivity is usually evaluated by measuring the provocation concentration of inhaled methacholine or histamine that causes a decrease in forced expiratory volume in 1 second of 20% (PC20). The percentage decrease in forced vital capacity at the PC20 (deltaFVC) has been proposed as a surrogate marker for maximal airway response. Individuals with allergic rhinitis and no clinical evidence of asthma frequently exhibit airway hypersensitivity. OBJECTIVE: To compare the deltaFVC between patients with allergic rhinitis and mild asthmatic patients with a similar degree of airway hypersensitivity. METHODS: A retrospective analysis of methacholine challenge test data from 72 children with allergic rhinitis and airway hypersensitivity (methacholine PC20 < 16 mg/mL) (rhinitis group) and from 72 children with mild atopic asthma matched to the rhinitis group regarding the methacholine PC20 (asthma group). The deltaFVC was calculated on the concentration-response curve to methacholine. RESULTS: The mean +/- SD deltaFVC was significantly lower in the rhinitis group (15.0% +/- 3.6%) vs the asthma group (17.4% +/- 5.3%) (P = .002). There was no significant correlation between the deltaFVC and PC20 in the rhinitis (r = -0.101; P = .41) and asthma (r = -0.023; P = .85) groups when 2 patients with PC20 less than 1 mg/mL were excluded from each group. CONCLUSIONS: Patients with allergic rhinitis and airway hypersensitivity had a significantly lower deltaFVC than methacholine PC20-matched mild asthmatic patients, suggesting that the level of maximal airway response in patients with allergic rhinitis is lower than that in mild asthmatic patients with a similar degree of airway hypersensitivity.     

Mucosal symptoms elicited by fragrance products in a population-based sample in relation to atopy and bronchial hyper-reactivity

BACKGROUND: Exposure to perfume and fragrance products may, in some individuals, cause symptoms from the eyes and airways. The localization, character and risk factors of such symptoms in the general population are unknown. OBJECTIVE: To investigate both the localization and character of symptoms from the eyes and airways elicited by fragrance products, and the associations between such symptoms and skin prick test reactivity (atopy), methacholine bronchial hyper-reactivity (BHR), allergic rhinitis and asthma. METHODS: A questionnaire on mucosal symptoms elicited by fragrance products was posted to 1189 persons who had participated in a Danish population-based study of allergic diseases in 1997/1998. The study included measurement of BHR, atopy, forced expiratory volume in 1 s (FEV1), and serum eosinophilic cationic protein (serum ECP). RESULTS: The response rate was 79.6%. Symptoms from the eyes or airways elicited by fragrance products were reported by 42%. BHR (adjusted odds ratio 2.3, 95% confidence interval 1.5-3.5) was independently associated with symptoms from the eyes and airways elicited by fragrance products. There were no significant associations between these symptoms and atopy, FEV1 or serum ECP. CONCLUSIONS: Mucosal symptoms from the eyes and airways were common in this population. BHR was a significant and independent predictor of these symptoms. The lack of association with atopy suggested that IgE-mediated allergic mechanisms do not play a major role in the development of these symptoms.     

Bronchial hyperresponsiveness in children with atopic rhinitis: a 7-year follow-up

BACKGROUND: A high prevalence of bronchial hyperresponsiveness (BHR) was found in atopic subjects with rhinitis. Those subjects may be at higher risk for developing bronchial asthma. We evaluated, in a 7-year follow-up, BHR and atopy in a homogeneous population of nonasthmatic children with allergic rhinitis (AR), and their role in asthma development. METHODS: Twenty-eight children (6-15 years) with AR were studied. At enrollment (T(0)), skin tests, total serum IgE assay, peak expiratory flow (PEF) monitoring and methacholine (Mch) bronchial challenge were performed. BHR was computed as the Mch dose causing a 20% forced expiratory volume (FEV)(1) fall (PD(20)FEV(1)) and as dose-response slope (D(RS)). Subjects were reassessed after 7 years (T(1)) using the same criteria. RESULTS: At T(0), 13 children (46%), showing a PD(20)FEV(1) <1526 microg of Mch, had BHR (Mch+), although PEF variability (PEFv) was within normal limits. None of the children with negative methacholine test developed bronchial asthma after 7 years. Of the 13 Mch+, only two reported asthma symptoms after 7 years. No significant change was seen in the other parameters of atopy considered. CONCLUSION: Children with allergic rhinitis present a high prevalence of BHR. Nevertheless, their PEFv is normal and the rate of asthma development low.     

The determinants of bronchial hyperresponsiveness in patients with allergic rhinitis.

BACKGROUND: Patients with allergic rhinitis and bronchial hyperresponsiveness (BHR) may be at higher risk of developing asthma. OBJECTIVE: To investigate whether reactivity to aeroallergens in skin prick testing (SPT) and serum eosinophil cationic protein levels can be used to predict BHR in allergic rhinitis patients. METHODS: Fifty-nine consecutive patients with allergic rhinitis underwent SPTs using grass, tree, weed, parietaria, Alternaria, Aspergillus, mites, and cat and dog dander extracts. Methacholine challenge tests were performed using spirometry. RESULTS: Methacholine-induced BHR was detected in 23 patients (39%). Of 59 patients, 14 had 1 positive SPT response, 35 had 2 to 4 positive responses, and 10 had more than 4 positive responses. There was a significant inverse correlation between methacholine provocation concentration that caused a decrease in forced expiratory volume in 1 second of 20% (PC20) and the number of positive SPT responses (r = -0.28; P = .03). The BHR-positive patients had a mean of 4 positive SPT responses, whereas BHR-negative patients had a mean of 2.6 (P = .04). Nine BHR-positive patients (39%) and only 1 BHR-negative patient (3%) had more than 4 positive SPT responses (P < .001). There was no correlation between serum eosinophil cationic protein levels and methacholine PC20 doses. There was a strong association between hyperresponsiveness to methacholine and both cat and dog dander sensitivity (P < .001 and P = .001, respectively). CONCLUSIONS: Allergic rhinitis patients with SPT responses to a higher number of allergens are more likely to have BHR. Whether the number of positive SPT responses correlates with the risk of developing asthma in allergic rhinitis patients remains to be determined.     

Once-daily budesonide inhalation powder (Pulmicort Turbuhaler) maintains pulmonary function and symptoms of asthmatic children previously receiving inhaled corticosteroids.

BACKGROUND: The incidence of pediatric asthma has increased dramatically over the past few decades, with approximately 5% of American children affected by the disease. OBJECTIVES: To compare the efficacy and safety of once-daily budesonide Turbuhaler with placebo in asthmatic children previously treated with orally inhaled corticosteroids. METHODS: This randomized, double-blind, placebo-controlled, multicenter (17 centers) study included 274 male and female children (aged 6 to 17 years) with a history of asthma for at least the previous 6 months. Patients received placebo or budesonide Turbuhaler (200 microg or 400 microg) once daily for 12 weeks. Efficacy variables included mean changes from baseline in forced expiratory volume in 1 second (FEV1), AM and PM peak expiratory flow rates (PEFRs), nighttime and daytime asthma symptom severity scores, patient discontinuations, use of beta2-agonists as breakthrough medication, forced vital capacity (FVC), and midexpiratory flow rate between 25% and 75% of FVC (FEF25%-75%). Safety was evaluated by adverse events, physical examinations, vital signs, and laboratory tests. RESULTS: Baseline characteristics were comparable among treatment groups. Percentage of predicted FEV1 at baseline was 76.6 +/- 6.9 for placebo, 77.5 +/- 7.1, and 77.0 +/- 7.8 for the budesonide Turbuhaler 200 microg and 400 microg groups, respectively. Significantly (P < or = 0.024) more placebo patients (24%) discontinued treatment because of disease deterioration or no improvement than budesonide Turbuhaler 200 microg (11%) or 400 microg patients (10%). Patients receiving budesonide Turbuhaler experienced significant improvements in FEV1 compared with patients receiving placebo (P < or = 0.015). Significant (P < or = 0.041) improvements over placebo also were observed in AM and PM PEFRs, FVC, FEF25%-75%, nighttime and daytime asthma symptoms, and amount of beta2-agonist used in both budesonide Turbuhaler groups. Adverse events were generally mild or moderate in intensity and similar among treatment groups. CONCLUSIONS: Once-daily budesonide Turbuhaler is effective and safe in children with persistent asthma previously maintained on at least twice-daily dosing regimens of inhaled corticosteroids.     

Impact of allergic rhinitis on asthma: effects on spirometric parameters

Background:  Close association exists between allergic rhinitis and asthma. Moreover, allergic rhinitis is a strong risk factor for the onset of asthma in adults. This study was aimed at evaluating a large group of patients with moderate-to-severe and persistent allergic rhinitis alone for investigating the presence of spirometric abnormalities and possible risk factors related to it.
Methods:  A total of 392 patients with persistent allergic rhinitis were prospectively and consecutively evaluated. Clinical examination, skin prick test and spirometry were performed in all patients.
Results:  There were 24 (6.1%) patients with forced vital capacity (FVC < 80%) of predicted, 50 (12.8%) with forced expiratory volume in the first second (FEV₁ < 80%) of predicted and 341 (87.0%) with forced expiratory flow at 25% and 75% of the pulmonary volume (FEF_25–75) < 80% of predicted. The logistic regression analysis evidenced that rhinitis duration (OR_Adj: 1.9/year) and sensitization to house dust mites (OR_Adj: 8.2) were significantly associated with impaired values of 2 or 3 spirometric parameters.
Conclusion:  This study highlights the close link between upper and lower airways and the role of some risk factors, such as duration and mites sensitization, as early prognostic markers of bronchial involvement in patients with moderate-to-severe and persistent allergic rhinitis alone.     

Interleukin-13-dependent bronchial hyper-responsiveness following isolated upper-airway allergen challenge in a murine model of allergic rhinitis and asthma

BACKGROUND: We have previously shown that isolated allergic sensitization and challenge of the upper airway results in lower-airway inflammation, which supports the concept of the united airways. OBJECTIVE: This study investigates the hypothesis that isolated upper-airway allergic sensitization is sufficient to induce bronchial hyper-responsiveness (BHR), characteristic of asthma, and that IL-13 is an essential mediator in both the upper and lower airways. METHODS: BALB/c mice were sensitized and challenged by intranasal instillation of allergen ovalbumin (OVA) using our standard protocol. BHR to methacholine was determined and inflammation in nares and lung was assessed. RESULTS: Isolated intranasal application of allergen in awake animals resulted in almost exclusive deposition in the upper airways while in anaesthetized mice there was almost equal distribution in the upper and lower airways. We have demonstrated significant BHR to methacholine challenge in animals receiving OVA only in the upper airway. Also noted was concomitant increase in eosinophilic infiltrates in lung and nares as well as increased granulocytes and IL-13 levels in bronchoalveolar lavage (BAL) fluid. Using a polyclonal anti-IL-13 antibody we have shown inhibition of airways inflammation, both in nares and in lung with significant reduction of granulocytes in BAL from anti-IL-13 treated mice (P<0.0001). Anti-IL-13 treatment also abrogates allergen-induced BHR (P<0.01). CONCLUSION: These data suggest that isolated upper-airway allergen deposition initiates allergic responses along the entire airway. IL-13 mediates both airway inflammation and BHR and may play a role in the communication between the upper and lower airways.     

The effectiveness of high-dose inhaled budesonide therapy in the treatment of acute asthma exacerbations in children.

BACKGROUND: International guidelines recommend the use of systemic steroids for the treatment of acute asthma attack if it has not been resolved within 24 to 36 hours of home management with regular beta2 mimetic inhalation. Such therapy for infrequent exacerbations is unlikely to have serious systemic effects. Unfortunately, many patients receiving frequent courses are potentially at risk for corticosteroid-induced side effects such as adrenal suppression, depression of linear growth, and osteoporosis. OBJECTIVE: To decrease the use of frequent oral corticosteroid courses in children, this study was designed to evaluate the efficacy of high-dose inhaled steroids in comparison with oral steroids, in the therapy of acute asthma exacerbations in children. METHODS: Sixty children who have experienced an acute exacerbation of asthma unresponsive to home management with regular use of inhaled beta2 mimetics, yet not severe enough to hospitalize, were randomized to be treated with either high-dose inhaled budesonide (1,600 microg daily) or oral methylprednisolone (1 mg/kg daily) plus medium-dose inhaled budesonide (800 microg daily, both in addition to inhaled terbutaline, 2,000 microg daily). Pre- and posttreatment pulmonary index scores, forced expiratory volume in one second (FEV1), forced vital capacity (FVC), FEV1/FVC and forced expiratory flow 25% to 75% (FEF25%-75%) were evaluated. RESULTS: The mean number of decrease in pulmonary index score was 2.61 +/- 1.12 in the high-dose budesonide-receiving group (group I) and 1.90 +/- 1.08 in the oral steroid-receiving group (group II). There was a statistically significant difference between the two groups, in favor of group I (P = .038). No statistically significant difference was detected between the two groups with respect to the increase in lung function test measurements (FEV1, FEV1/FVC, FEF25%-75%; P = .790, .959, .819, respectively). CONCLUSIONS: Short-term high-dose budesonide therapy can be considered an alternative for children who are experiencing an acute asthma attack that is unresponsive to home management with regular use of an inhaled beta2 mimetic, yet who are not severe enough to hospitalize.     

Nasal eosinophilic inflammation contributes to bronchial hyperresponsiveness in patients with allergic rhinitis

There are increasing evidences that allergic rhinitis (AR) may influence the clinical course of asthma. We conducted methacholine challenge test and nasal eosinophils on nasal smear to patients with allergic rhinitis in order to investigate the mechanism of connecting upper and lower airway inflammation in 35 patients with AR during exacerbation. The methacholine concentration causing a 20% fall in FEV1 (PC20) was used as thresholds of bronchial hyperresponsiveness (BHR). Thresholds of 25 mg/dL or less were assumed to indicate BHR. All patients had normal pulmonary function. Significant differences in BHR were detected in the comparison of patients with cough or postnasal drip and without cough or postnasal drip. There were significant differences of PC20 between patients with cough or postnasal drip and those without cough or postnasal drip (3.41+/-3.59 mg/mL vs 10.2+/-1.2 mg/mL, p=0.001). The levels of total IgE were higher in patients with seasonal AR than in patients with perennial AR with exacerbation (472.5+/-132.5 IU/L vs. 389.0+/-70.9 IU/L, p<0.05). Nasal eosinophils were closely related to log PC20 (r=-0.65, p<0.01). These findings demonstrated that nasal eosinophilic inflammation might contribute to BHR in patients with AR.     

IL-5 and thromboxane A2 receptor gene polymorphisms are associated with decreased pulmonary function in Korean children with atopic asthma

BACKGROUND: Asthmatic airways undergo chronic inflammatory cell infiltration by T cells and eosinophils, which results in sustained airway hyperresponsiveness. IL-5 is important for eosinophil-induced airway inflammation and airway hyperresponsiveness. Thromboxane A2 and its receptor, TBXA2R, are involved in constriction of respiratory smooth muscles and may play a role in thickening and remodeling of airways, which contributes to the severity of asthma. The relationship between IL-5 and TBXA2R gene polymorphisms and pulmonary function in children with asthma has rarely been examined. OBJECTIVE: To determine whether IL-5 (T-746C) and TBXA2R (T924C) gene polymorphisms are associated with asthma phenotype and pulmonary function in Korean children with atopic and nonatopic asthma. METHODS: We conducted an association study between known polymorphisms of IL-5 (T-746C) and TBXA2R (T924C) and asthma phenotype and the parameters of atopy and pulmonary function in atopic and nonatopic Korean children with asthma. The subjects were 240 atopic children with asthma, 70 nonatopic children with asthma, and 106 nonatopic healthy children. Asthma phenotypes and bronchial responsiveness to methacholine were determined by a physician. IL-5 and TBXA2R gene polymorphisms were determined by genotyping by using PCR-RFLP assays. RESULTS: The genotype frequencies of IL-5 and TBXA2R polymorphisms did not differ between healthy controls and atopic or nonatopic children with asthma. A significant association was observed between the IL-5 polymorphism and forced expiratory flow at 25% to 75% of forced vital capacity (FEF 25-75% ; %; P = .002), and between the TBXA2R polymorphism and FEV 1 (%; P = .035) and FEF 25-75% (%; P = .042) in children with atopic asthma, whereas no such association between the polymorphisms and lung function was observed in nonatopic or control children. In atopic children with asthma, we identified a significant gene-gene interaction in that the combination of the IL-5 (T-746C) and TBXA2R (T924C) mutant alleles was shown to be associated with reduced pulmonary function as determined by FEF 25-75% (%) measurement. CONCLUSION: The current study indicates that IL-5 (T-746C) and TBXA2R (T924C) polymorphisms alone are associated with spirometric markers of asthma severity, whereas they are not associated with presence of asthma per se. In addition, the data suggest that an interaction between IL-5 and TBXA2R genes may contribute to the severity of asthma, especially atopic asthma. These results suggest that IL-5 and TBXA2R genes may be disease-modifying genes in Korean children with atopic asthma.     

Bronchial hyperresponsiveness in young children with allergic rhinitis and its risk factors

BACKGROUND: Subjects with allergic rhinitis but no clinical evidence of asthma have greater bronchial hyperresponsiveness (BHR), and several factors have been implicated as its determinants. However, studies in young children are lacking. The aims of this study were to evaluate the prevalence of BHR in young children with allergic rhinitis and to investigate its risk factors. METHODS: Methacholine bronchial challenges were performed in 4- to 6-year-old nonasthmatic children with allergic rhinitis (n = 83) and in healthy nonatopic controls (n = 32), using a modified auscultation method. The end-point was defined as the appearance of wheezing and/or oxygen desaturation. Subjects were considered to have BHR when they had end-point concentrations of methacholine 相似文献   

Once-daily budesonide via Turbuhaler improves symptoms in adults with persistent asthma.

BACKGROUND: Previous studies have demonstrated the efficacy and safety of twice-daily budesonide Turbuhaler (Pulmicort Turbuhaler, AstraZeneca, Wilmington, DE) for the treatment of mild to severe asthma. OBJECTIVE: To compare the efficacy and safety of budesonide Turbuhaler administered once daily each morning with placebo in inhaled corticosteroid-naive adults with persistent asthma. METHODS: In this randomized, double-blind, placebo-controlled, multicenter study, 177 adults (aged 18 to 70 years) received placebo or once-daily budesonide Turbuhaler (400 microg) for 12 weeks. Efficacy variables included mean changes from baseline in forced expiratory volume in 1 second (FEV1) and AM/PM peak expiratory flow rate (PEFR), and nighttime/daytime asthma symptom scores, patient discontinuations, use of breakthrough medication (albuterol), forced vital capacity (FVC), forced expiratory flow between 25% and 75% of FVC (FEF25%-75%), and quality of life assessments. Safety was evaluated based on adverse events, physical examinations, vital signs, and laboratory tests. RESULTS: Demographic and baseline characteristics were comparable between study groups. The mean percentages of predicted FEV1 at baseline were 71.9 +/- 9.8 in patients receiving budesonide Turbuhaler and 70.6 +/- 11.0 in patients receiving placebo. Mean changes from baseline over the 12-week treatment period in FEV1 were significantly (P = 0.007) improved in patients receiving once-daily budesonide Turbuhaler compared with placebo (0.31 L and 0.17 L, respectively). Significant (P < or = 0.037) improvements over placebo also were observed in AM PEFR, nighttime/daytime asthma symptoms, and albuterol use with budesonide Turbuhaler treatment. Adverse events were generally mild or moderate in intensity and similar between study groups. CONCLUSIONS: Budesonide Turbuhaler 400 microg administered once daily in the AM is efficacious and safe for inhaled corticosteroid-naive asthmatic adults.     

The importance of maximal airway response to methacholine in the prediction of asthma development in patients with allergic rhinitis

BACKGROUND: Allergic rhinitis is a known predictor and correlate of asthma incidence. However, it is not clear which patients with allergic rhinitis are at greater risk of the development of asthma. OBJECTIVE: The aim of this study was to investigate whether airway hypersensitivity and/or increased maximal response on the dose-response curve to methacholine would predict the development of asthma in subjects with allergic rhinitis. METHODS: One hundred and forty-one children with allergic rhinitis were prospectively studied for 7 years. At the initiation of the study, bronchial provocation test with methacholine using a stepwise increasing concentration technique was performed to measure PC(20) (provocative concentration causing a 20% fall in FEV(1)) and maximal response. Each subject was evaluated at least every 6 months and details of asthmatic symptoms or signs experienced during the intervening period were taken. RESULTS: Twenty of 122 subjects available for the follow-up developed asthma. Nine (19.6%) of 46 hypersensitive (PC(20) < 18 mg/mL) subjects developed asthma, compared with 11 (14.5%) of 76 normosensitive subjects (P = 0.462). Eight (32%) of 25 subjects without maximal response plateau developed asthma, compared with 12 (12.4%) of 97 subjects with maximal response plateau (P = 0.018). Score test for trend revealed a significant association between the level of maximal response (P = 0.007), but not the degree of methacholine PC(20) (P = 0.123), and the future development of asthma. CONCLUSION: An increased maximal airway response to methacholine is shown to be a better predictor for the future development of asthma in patients with allergic rhinitis, than airway hypersensitivity to methacholine.     

Sex differences of small airway function and fractional exhaled nitric oxide in patients with mild asthma

BackgroundSex differences of small airway function (SAF) and fractional exhaled nitric oxide (FeNO) in patients with mild asthma remain unclear.ObjectiveTo evaluate sex differences of SAF and FeNO in patients with mild asthma confirmed by positive methacholine challenge test (MCT) result.MethodsThis cross-sectional, double-centered, observational study enrolled 1609 adult patients with forced expiratory volume in 1 second greater than or equal to 80% and suspected asthma symptoms. Data of spirometry, FeNO, impulse oscillometry measurements, and peripheral blood test result were compared between males and females. The receiver-operating characteristic curves of SAF parameters and FeNO in predicting positive MCT result were also calculated.ResultsIn patients with mild asthma matched by age, males had better SAF but higher FeNO levels than females (60 [29.27%] vs 187 [46.75%] for small airway dysfunction, 78.6% vs 72.0% for forced expiratory flow [FEF]_50%, 67.5% vs 60.1% for FEF_75%, 73.7% vs 67.4% for FEF_25%-75%, and 42.0 ppb vs 29.0 ppb for FeNO, respectively, all P ≤ .001). The FeNO levels in male current smokers were considerably lower than those of nonsmokers. SAF and FeNO values declined more rapidly with age among female than male patients with asthma. The optimal cutoff values of FEF_25%-75%, FEF_50%, and FeNO for predicting a positive MCT result were 81.5%, 86.4%, and 41.0 ppb in males vs 73.7%, 76.9%, and 35.0 ppb in females.ConclusionIn patients with mild asthma, the female patients have worse SAF, lower FeNO levels, and a more prominent decline trend of those parameters with age than males. Sex-specific cutoff values should be considered when SAF parameters (FEF_25%-75%, FEF_50%), alone or combined with FeNO, are used to predict positive MCT result in asthma diagnosis.     

Nasal eosinophils display the best correlation with symptoms, pulmonary function and inflammation in allergic rhinitis

BACKGROUND: The pathogenesis of allergic rhinitis and its link with asthma are well known. Nevertheless, a complete cross-sectional evaluation of the usually available clinical, functional and immunological parameters has never been made. We assessed nasal symptoms and flow, cytology, cytokines, pulmonary function and methacholine positivity in a large number of patients with pure pollinosis. METHODS: Young men presenting at a military hospital for routine follow-up were recruited for the study. They had to suffer from rhinitis alone (without asthma) for at least 2 years and had to have a positive skin prick test to pollens only. During the pollen season, they underwent symptom evaluation, measurement of nasal flow, nasal scraping and lavage (cell count and assay for IL-4, IL-5, IL-8 and IFNgamma), pulmonary function tests and methacholine challenge. RESULTS: Fifty subjects (23.7+/-4.9 years old) were enrolled. All patients had high clinical scores (9.5+/-1.6) and inflammatory cells (eosinophils: 10.5+/-4 and neutrophils 21.3+/-6) and low nasal flow (482+/-111 ml/s). We found that the number of eosinophils in nasal scrapings highly correlated with all the above-mentioned parameters, including nasal flow, cytokines and spirometric values. A significant positive correlation was found between all inflammatory cells and all cytokines. IL-8, IL-4 and neutrophils displayed only a partial correlation with pulmonary parameters (FEV1, FVC and FEF25-75%), at variance wit IL-5 and eosinophils. Methacholine test positivity significantly correlated with the number of eosinophils in the nasal smear. CONCLUSION: Eosinophils in the nasal smear display the best correlation with all the clinical and immunological parameters in allergic rhinitis and also correlate well with methacholine response.     

Basement membrane thickening and clinical features of children with asthma

BACKGROUND: Asthma is a chronic inflammatory disease, characterized by airway inflammation, bronchial hyper-responsiveness, and airway obstruction. Although asthma induces partially reversible airway obstruction, obstruction can sometimes become irreversible. This may be a consequence of airway remodeling, which includes a number of structural changes, such as epithelial detachment, basement membrane (BM) thickening, smooth muscle hypertrophy, and new vessel formation. This study evaluated children with asthma for the presence of BM thickening. METHODS: Eighteen children with asthma and 24 control subjects underwent flexible bronchoscopy with endobronchial biopsy. Light microscopy was used to measure BM thickness in paraffin-embedded biopsy sections. The association between BM thickening and age, sex, duration of asthma, asthma severity, FEV(1), FEV(1)/FVC, FEF(25-75%), methacholine PC(20), eosinophil count, and presence of atopy was examined. RESULTS: Basement membrane thickness was greater in subjects with asthma (8.3 +/- 1.4 microM) than in control subjects (6.8 +/- 1.3 microM, P = 0.0008). Multiple regression analysis revealed that sex, FEV(1)/FVC, total IgE, and atopy (IgE for Dermatophagoides pteronyssinus >0.34 kUA/l) were significant predictive factors for BM thickness. There was no significant association between BM thickness and age, duration of asthma, FEV(1), FEF(25-75%), methacholine PC(20), eosinophil count, or asthma severity. CONCLUSIONS: Basement membrane thickening has been known to be present in children with asthma. In addition, we report an association between BM thickness and sex, FEV(1)/FVC, total IgE, and the presence of IgE specific to D. pteronyssinus.