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Study objectives To investigate whether the bronchodilatory effect of deep inspiration is impaired in subjects with COPD. Methods We measured deep inspiration-induced bronchodilation in 19 patients with COPD and 17 healthy subjects (mean age, 67.8 ± 7.1 years vs 62.5 ± 9.3 years, respectively [± SEM]). Each subject underwent a series of single-dose methacholine provocations to induce at least a 15% reduction in inspiratory vital capacity (IVC). When this was achieved, subjects were asked to perform four consecutive deep inspirations, after which the IVC measurement was repeated and the percentage of bronchodilation by deep inspiration was calculated. Results The percentage of reduction in IVC from baseline prior to the deep inspirations did not differ between the two groups (COPD, 20.1 ± 1.6%; healthy, 22.7 ± 2.4%; p=0.38); median single methacholine doses employed were 20 mg/mL (range, 0.025 to 75 mg/mL) and 25 mg/mL (range, 10 to 75 mg/mL), respectively (p = 0.19). Deep inspirations were not able to reverse bronchoconstriction in patients with COPD (bronchodilation, 3.9 ± 2.6%; p=0.15 by one-sample t test). Bronchodilation by deep inspiration was present in healthy subjects (13.7 ± 3.0%, p=0.0003), and was significantly higher than that of patient with COPD (p = 0.02). In patients with COPD, deep inspiration-induced bronchodilation correlated with the percentage of predicted transfer factor of the lung for carbon monoxide ( r = 0.53, p=0.05), but not with airway obstruction, as assessed by FEV 1 or FEV 1 /FVC. Conclusions The bronchodilatory ability of deep inspiration is lost in mild COPD. We speculate that the absence of deep inspiration-induced bronchodilation contributes to the development and severity of chronic respiratory symptoms in patients with COPD.

Study objective To develop and evaluate a brief, easy-to-administer symptom assessment scale for use as a preference-based outcome measure in clinical trials and cost-effectiveness studies in asthma. Design Cross-sectional survey with 2-week reproducibility assessment. Setting Ambulatory care: university asthma and allergy center. Participants One hundred sixty-one adults with asthma, 59% female, mean age 35 ± 11 years. Mean FEV 1 percent predicted was 86 ± 17%. Interventions The 11-item Asthma Symptom Utility Index (ASUI). Measurements and results Mean ASUI score for this sample was 0.71 ± 0.23, with a range from 0.02 to 1.0. The ASUI was reproducible (intraclass correlation coefficient = 0.74) and able to distinguish patients known to differ on disease severity according to clinician ratings (p 1 percent predicted (r = 0.27, p Conclusion The results of this study support the reliability and validity of the ASUI, suggesting it will be a useful, complementary patient outcome measure for clinical trials and cost-effectiveness studies comparing treatment alternatives for persons with asthma.

To develop and evaluate a brief, easy-to-administer symptom assessment scale for use as a preference-based outcome measure in clinical trials and cost-effectiveness studies in asthma.Cross-sectional survey with 2-week reproducibility assessment.Ambulatory care: university asthma and allergy center.One hundred sixty-one adults with asthma, 59% female, mean age 35+/-11 years. Mean FEV1 percent predicted was 86+/-17%.The 11-item Asthma Symptom Utility Index (ASUI).Mean ASUI score for this sample was 0.71+/-0.23, with a range from 0.02 to 1.0. The ASUI was reproducible (intraclass correlation coefficient = 0.74) and able to distinguish patients known to differ on disease severity according to clinician ratings (p0.001) and by an asthma disease severity scale score (p0.001). The instrument was also significantly correlated with FEV1 percent predicted (r = 0.27, p0.001), the Asthma Quality of Life Questionnaire (r = 0.77, p0.001), and the Health Utilities Index Mark 2 (r = 0.36, p0.001).The results of this study support the reliability and validity of the ASUI, suggesting it will be a useful, complementary patient outcome measure for clinical trials and cost-effectiveness studies comparing treatment alternatives for persons with asthma.

The IgE-mediated release of inflammatory substances from mast cells and basophils in vitro and, more recently, in vivo has proved to be a convenient model for studying mechanisms thought important in acute allergic reactions. The fact that IgE-mediated stimuli can initiate an immediate inflammatory response which can be manifest many hours after allergen exposure and that other triggers, including physical stimuli, can cause apparent mast cell activation suggests that these processes may be of general importance. Elucidating which cells and which chemical mediators play predominant roles in these reactions is a major challenge for the years ahead.