Despite the demonstrated efficacy of therapy with LTRAs in patients with CVA, the question of whether these agents are sufficient as monotherapy, or whether they should be used in addition to inhaled steroids, remains unresolved at this time, Subepithelial layer thickening, a pathologic feature of airway wall remodeling, is present in CVA, although to a […]
Patients with cough due to asthma should initially be treated with a standard antiasthmatic regimen of inhaled bronchodilators and inhaled corticosteroids. Quality of evidence, fair; net benefit, substantial; grade of recommendation. A potential pitfall of inhaled steroid therapy in patients with CVA is that the treatment itself may induce or exacerbate cough, which is likely […]
If reversible airflow obstruction is demonstrated in a patient with chronic cough, empiric therapy for asthma is appropriate, However, a patient with chronic cough due to asthma may present a diagnostic challenge, because physical examination and pulmonary function test results can be entirely normal, In this setting, bronchoprovocation testing with inhaled methacholine should be used […]
Multiple prospective studies have shown that asthma is among the most common etiologies of chronic cough (24 to 29%) in adult nonsmokers, Usually, cough is associated with the more typical symptoms of dyspnea and wheezing, Alternatively, an isolated cough may serve as a harbinger of future asthmatic episodes, In a subgroup of asthmatic patients, however, […]
The failure of FEVj-specific normal ranges of PD20FEVJ to improve sensitivity or specificity in detecting questionnaire-reported asthma or wheezing has several possible explanations. Measurements of airway responsiveness are imperfect at discriminating between asthmatics and nonasthmatics in population samples,’ and altering the criteria for an abnormal challenge test may have little impact relative to other sources […]
A number of mechanisms have been proposed as the basis for the relationship between nonspecific airway responsiveness and prechallenge pulmonary function.’ Because resistance to flow through a tube is inversely proportional to the radius to the fourth power, a given degree of bronchoconstrictor-induced circumferential airway narrowing can be expected to cause a proportionally larger increase […]
The 547 asymptomatic subjects with normal pulmonary function were grouped according to quintile of prechallenge FEV, (percent predicted), and the fifth percentiles of PD20FEV, within each quintile of FEV, were calculated (Table 2). The fifth percentile of methacholine PD20FEV, increased with increasing quintile of prechallenge FEV,. This relationship is shown graphically in Figure 1, in […]