Chronic Cough Due to Asthma: Treatment
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 lesser extent than in the typical form of asthma, Hence, chronic antiinflammatory therapy seems appropriate for patients with CVA, but the issue of whether treatment with LTRAs alone is sufficient to prevent the sequelae of chronic airway inflammation awaits further elucidation.
For patients with asthmatic cough that is refractory to treatment with inhaled corticosteroids and bronchodilators, in whom poor compliance or another contributing condition has been excluded, an LTRA may be added to the therapeutic regimen before the escalation of therapy to systemic corticosteroids. Quality of evidence, fair; net benefit, intermediate; grade of recommendation.
Patients with severe and/or refractory cough due to asthma should receive a short course (1 to 2 weeks) of systemic (oral) corticosteroids followed by inhaled corticosteroids. canadian helth& care mall
Quality of evidence, low; net benefit, substantial; grade of recommendation.
Other agents shown in prospective trials to be effective in treating asthmatic cough include inhaled terbutaline, metaproterenol, theophylline, nedocromil sodium, azelastine hydrochloride, a second-generation H1-receptor antagonist, and su-platast tosilate, a Th2 cytokine inhibitor (see Table 1), There are no data to suggest that these agents offer added benefit to a regimen of an inhaled bronchodilator and inhaled corticosteroid, with or without an LTRA. In a patient with chronic cough, asthma should always be considered as a potential etiology because asthma is a common condition with which cough is commonly associated. Quality of evidence, fair; net benefit, substantial; grade of recommendation. In a patient suspected of having CVA but in whom physical examination and spirometry findings are nondiagnostic, MIC testing should be performed to confirm the presence of asthma. However, a diagnosis of CVA is established only after the resolution of cough with specific antiasthmatic therapy. If MIC testing cannot be performed, empiric therapy should be administered; however, a response to steroid therapy will not exclude nonasthmatic eosinophilic bronchitis as an etiology of the patient’s cough. Quality of evidence, good; net benefit, substantial; grade of recommendation. Patients with cough due to asthma should initially be treated with a standard antiasthmatic regimen of inhaled broncho-dilators and inhaled corticosteroids. Quality of evidence, fair; net benefit, substantial; grade of recommendation.
Table 1—Treatment of Chronic Cough Associated With Asthma
|Study/Year||Age, yr||Study Design||Patients, No,||Treatment||Response Rate, %||Other Details||Quality of Evidence|
|Corrao et al/1979||16-40||Prospective,descriptive||6||Terbutaline(inhaled)||100||Low|
|Irwin et al/1997||ъ+1||PRDBPCcrossover||15||Metaproterenol(inhaled)||60||In 40%, cough due to other etiologies||Fair|
|Corrao et al/1979||16-40||Prospective,descriptive||6||Theophylline||100||Low|
|Crimi et al/1995||20-76 (44)|||PRDBPC||62||Theophylline||83||Response rate for all asthma symptoms||Fair|
|Crimi et al/1995||18-55 (37)|||PRDBPC||43||Nedocromilsodium||78||Response rate for all asthma symptoms||Fair|
|North American Tilade Study Group/1990||12-70 (35-2)!||PRDBPC||121||Nedocromilsodium||Improvement in treated patients, (p = 0,02)||Patients also ontheophylline and oral p-agonists||Fair|
|Dicpinigaitis et al/ 2002||27-62||PRDBPCcrossover||8||Zafirlukast||88||Suppression of cough reflex sensitivity 100%||Fair|
|Irwin et al/1997||55 ± 16j||PRDBPCcrossover||15||
|60||In 40%, cough due to other etiologies||Fair|
|Cheriyan et al/1994||Retrospective,descriptive||10||Prednisone 7-14 d, followed by beclomethasone diproprionate||100||80% required long-term ICSs for cough suppression||Low|
|Di Franco et al/2001||36 ± 16j||PRDBPC||36||Beclomethasone diproprionate (and albuterol)||Improvement in treated patients (p < 0,01)||Compared to placebo and albuterol||Fair|
|Doan et al/1992||4-71||Prospective,descriptive||10||Prednisone (20-60 mg/d)||100||Subsequent therapy with ICSs||Low|
|Shioya et al/1998||25-63 (47,1)!||
|22||Azelastinehydrochloride||Improvement in treated patients(p < 0,001)||Low|
|Shioya et al/2002||22-69 (44,7)!||PRDBPC||20||Suplatast tosilate||Improvement in treated patients(p < 0,01)||Fair|