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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Bronchial Hyperreactivity, Bronchial Provocation Tests, Exhalation, Female, Humans, Male, Methacholine Chloride, Middle Aged, Nitric Oxide, Smoking, Surveys and Questionnaires.
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Is bronchial responsiveness related to increased exhaled NO ( FE ( NO ) ) in non-smokers and decreased FE ( NO ) in smokers? Context: Both atopy and smoking are known to be associated with increased bronchial responsiveness. Fraction of nitric oxide (NO) in the exhaled air (FE(NO)), a marker of airways inflammation, is decreased by smoking and increased by atopy. NO has also a physiological bronchodilating and bronchoprotective role. To investigate how the relation between FE(NO) and bronchial responsiveness is modulated by atopy and smoking habits. Exhaled NO measurements and methacholine challenge were performed in 468 subjects from the random sample of three European Community Respiratory Health Survey II centers: Turin (Italy), Gothenburg and Uppsala (both Sweden). Atopy status was defined by using specific IgE measurements while smoking status was questionnaire-assessed. Increased bronchial responsiveness was associated with increased FE(NO) levels in non-smokers (p = 0.02) and decreased FE(NO) levels in current smokers (p = 0.03). The negative association between bronchial responsiveness and FE(NO) was seen only in the group smoking less <10 cigarettes/day (p = 0.008). Increased bronchial responsiveness was associated with increased FE(NO) in atopic subjects (p = 0.04) while no significant association was found in non-atopic participants. The reported interaction between FE(NO) and smoking and atopy, respectively were maintained after adjusting for possible confounders (p-values<0.05).
assistant
The present study highlights the interactions of the relationship between FE(NO) and bronchial responsiveness with smoking and atopy, suggesting different mechanisms behind atopy- and smoking-related increases of bronchial responsiveness. Final Decision: yes