Influence of atopy on exhaled nitric oxide in patients with stable asthma and rhinitis. Ch. Gratziou, M. Lignos, M. Dassiou, Ch. Roussos. #ERS Journals Ltd 1999. ABSTRACT: The level of exhaled NO is increased in patients with allergic asthma and seasonal rhinitis. The aim of this study was to investigate the significance of atopy on NO production in the lower airways.Measurements of exhaled NO were performed in 131 stable asthmatic patients with chronic mild asthma (95 atopics and 36 nonatopics), 72 patients with perennial rhinitis (57 atopics and 15 nonatopics) and 100 healthy controls (20 atopics and 80 nonatopics).Patients with either asthma or rhinitis had higher exhaled NO values (13.3& 1.2 parts per billion (ppb) and 11.7 1.1 ppb) than control subjects (4.8 0.3 ppb, p<0.01). Exhaled NO levels were significantly higher in atopic asthmatics (19 3.6 ppb) compared with nonatopic patients (5.6 0.8 ppb, p<0.001). Similar findings were observed in patients with rhinitis (13.3 1.3 ppb in atopics and 5.8 1.2 ppb in nonatopics, p<0.001). No difference was found in NO levels between atopic and nonatopic control subjects (4.8 0.8 ppb, and 4.5 0.3 ppb).In summary, this study has shown that increased exhaled NO levels are detected only in atopic patients with asthma and/or rhinitis and not in nonatopic patients. These findings may suggest that it is rather the allergic nature of airways inflammation, which is mainly responsible for the higher NO production in the lower airways. Eur Respir J 1999; 14: 897±901.
To improve understanding of the mechanisms of action of oral corticosteroids in asthma, we have conducted a double-blind, placebo-controlled study with prednisolone (20 mg for 2 wk followed by 10 mg for 4 wk) or placebo in 14 and 13 atopic corticosteroid-naive asthmatic subjects, respectively. Before and after treatment subjects underwent bronchoscopy with bronchoalveolar lavage (BAL) and bronchial biopsy. Treatment with prednisolone, but not placebo, significantly reduced asthma symptoms (from mean +/- SEM total weekly score of 34 +/- 6.2 to 15.7 +/- 3.2, p = 0.02) and albuterol usage (from mean +/- SEM number of puffs/wk of 29.7 +/- 6.2 to 18.2 +/- 3.7, p = 0.01) and significantly increased FEV1 (from 89.8 +/- 4.4% to 99.3 +/- 4.1% of predicted, p = 0.03). There were no significant changes in inflammatory or epithelial cell counts, levels of T-cell activation or albumin concentration in BAL. However, immunohistochemistry of bronchial biopsies showed that in the submucosa prednisolone significantly decreased numbers of mast cells by 62% (from median 45 to 17/mm2, p = 0.01), eosinophils by 81% (from median 30.1 to 5.7/mm2, p = 0.004), and CD4+ T-cells by 68% (from median 64.6 to 18.5/mm2, p = 0.02). In the epithelium only the reduction in the numbers of eosinophils was significant (from median 1.1 to 0/mm of epithelium, p = 0.02). There were no significant changes in any cell counts in the subjects receiving placebo, and comparison of the changes between the treatment groups identified a significant prednisolone-related reduction in submucosal eosinophil and mast cell counts (p = 0.003 and 0.03, respectively). The temporal association between the clinical and physiologic improvement, and the correlation between the magnitude of change in CD4+ T-cell counts in the submucosa and increase in PC20 methacholine (rs = 0.60, p = 0.049) suggests that the reduction in airways inflammatory cell numbers underlies the clinical efficacy of oral corticosteroids.
Exhaled nitric oxide (eNO) has been proposed as a potential indirect marker of lower airway inflammation in asthma. To investigate the existence of lower airways inflammation in allergic rhinitis eNO measurements were performed in 32 patients with symptomatic and asymptomatic seasonal allergic rhinitis early in and out of pollen seasons and in 80 healthy volunteers. To further define how exhaled NO is modified by therapy, NO levels were detected following 1-month treatment with either inhaled steroids or non-steroids therapy with nedocromil. Exhaled NO (mean +/- SE) was significantly elevated in patients with seasonal allergic rhinitis with and without symptoms (24.2 + 2.5 and 13.9 + 2.9 ppb, respectively) as compared to healthy volunteers (4.5 + 0.3 ppb) both in and out of pollen season (21.2 + 2.1 and 9.0 + 1.4 p.p.b., respectively) with a higher increase during the allergen exposure in season. Higher levels of exhaled NO were detected in patients with symptoms, either from the upper or lower airways, and with bronchial hyperreactivity. The increased exhaled NO in symptomatic patients was reduced only by inhaled steroids and not by nedocromil. These findings possibly suggest the existence of lower airway inflammation in both symptomatic and asymptomatic patients with seasonal allergic rhinitis in and out of pollen season. Thus, exhaled NO may be used as a non-invasive index for early detection of lower airway inflammation and for monitoring the optional treatment in patients with seasonal allergic rhinitis.
Antioxidant foods seem to be a non-pharmacological, protective dietary pattern for asthma development in children irrespectively of atopy or heredity; AEI was a rough indicator and the role of antioxidants in allergic diseases is still under consideration.
Background The Global Asthma Network (GAN), by using the International Study of Asthma and Allergies in Childhood (ISAAC) methodology, has updated trends in prevalence of symptoms of childhood allergic diseases, including non‐infective rhinitis and conjunctivitis (‘rhinoconjunctivitis’), which is reported here. Methods Prevalence and severity of rhinoconjunctivitis were assessed by questionnaire among schoolchildren in GAN Phase I and ISAAC Phase I and III surveys 15–23 years apart. Absolute rates of change in prevalence were estimated for each centre and modelled by multi‐level linear regression to compare trends by age group, time period and per capita national income. Results Twenty‐seven GAN centres in 14 countries surveyed 74,361 13‐ to 14‐year‐olds (‘adolescents’) and 45,434 6‐ to 7‐year‐olds (‘children’), with average response proportions of 90% and 79%, respectively. Many centres showed highly significant (p < .001) changes in prevalence of rhinoconjunctivitis in the past year (‘current rhinoconjunctivitis’) compared with ISAAC. The direction and magnitude of centre‐level trends varied significantly (p < .001) both within and between countries. Overall, current rhinoconjunctivitis prevalence decreased slightly from ISAAC Phase III to GAN: −1.32% per 10 years, 95% CI [−2.93%, +0.30%] among adolescents; and −0.44% [−1.29%, +0.42%] among children. Together, these differed significantly (p < .001) from the upward trend within ISAAC. Among adolescents, centre‐level trends in current rhinoconjunctivitis were highly correlated with those for eczema symptoms (rho = 0.72, p < .0001) but not with centre‐level trends in asthma symptoms (rho = 0.15, p = .48). Among children, these correlations were positive but not significant. Conclusion Symptoms of non‐infective rhinoconjunctivitis among schoolchildren may no longer be on the increase globally, although trends vary substantially within and between countries.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.