Should Non-eosinophilic Asthmatic Subjects be Treated With Inhaled Corticosteroids?

General objective: To assess whether inhaled corticosteroids alone or in combination with long-acting beta-2 agonists are an effective treatment in non-eosinophilic asthmatic subjects. Specific objective 1. To compare the change in clinical and functional outcomes after treatment with fluticasone or placebo in non-eosinophilic asthmatic subjects. Specific objective 2. To assess whether the combination of inhaled corticosteroids (ICS) and with long-acting beta-2 agonists provides an improvement of asthma control compared to the treatment with ICS or placebo in non-eosinophilic asthmatics. Hypothesis: Treatment with ICS induces a significant clinical and physiologic improvement of non-eosinophilic asthmatic subjects. ICS/Salmeterol also provides a clinical and physiologic benefit compared to placebo. Primary end point: Asthma Control Questionnaire (ACQ) score after 4 weeks of treatment with ICS or placebo. The Asthma Control Questionnaire has been chosen as a primary outcome since it is the most relevant clinical measure to assess asthma control over a short period of time. In patients whose asthma is stable between clinic visits, reliability of the ACQ is high (intraclass correlation coefficient (ICC)=0.90). Furthermore, the questionnaire is also very responsive to changes in asthma control(7). Therefore, this is the ideal tool to assess and compare the changes in asthma control over a short period of time. This instrument has the advantage of including both asthma symptoms as well as forced expiratory flow in one second (FEV1). A change of ACQ of 0.5 has been shown to be clinically significant. Therefore, we will be able to assess whether or not a treatment with ICS has the ability to significantly improve asthma control in non-eosinophilic asthmatic subjects. The questionnaire is provided in appendix III. Other functional and clinical outcomes such as quality of life, FEV1, provocative concentration of methacholine inducing a 20% fall in FEV1 (PC20), number of rescue medication and number of asthma exacerbations will also be assessed as secondary outcomes. The study has two steps: The first step will be a randomized double-blind, placebo-controlled, multicenter study comparing the efficacy of ICS and placebo for 4 weeks in asthmatic subjects without sputum eosinophilia followed by an open ICS/salmeterol 4-week treatment for all subjects. (See study design in appendix III). Inclusion criteria One hundred subjects will be enrolled.