Conditions: Asthmatic Smokers Non-asthmatic Smokers
Keywords: asthmatics smokers inhaled corticosteroids leukotriene receptor antagonists
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 105
Healthy volunteers: yes

Brief summary:
The purpose of this study is:

1. To compare neutrophilia, eosinophilic inflammatory markers and asthma symptom indices between smokers and non-smokers.
2. To elucidate the mechanism by which cigarette smokers are resistant to corticosteroids.

Detailed description:
Many smokers have insufficient control of their symptoms due to inefficacy of ICS in this subpopulation of asthmatics. Cigarette smoking has been shown to stimulate production of cysLTs. CysLTs could activate production of IL-8 for neutrophilia as well as cause eosinophilia in the airway of asthmatics.

LTRAs are felt to be less efficacious than ICS in smokers with asthma. However, LTRA's unique mechanism of action could be particularly efficacious in preventing worsening symptoms and lung function for smokers with asthma. Given this, along with the fact that ICS are less effective in smokers, targeting cysLT could lead to significant clinical benefits for asthmatic smokers.

Data from this study may possibly serve as crucial data for the significant clinical benefits for asthmatic smokers and determination of the mechanism of corticosteroid resistance in smokers with asthma.

Arms:
arm 1: Asthmatic smokers treated with combination therapy:

Fluticasone propionate dosage - DPI 250 mcg BID for 3 months Salmeterol dosage - DPI 50 mcg BID for 3 months arm 2: Asthmatic smoker treated with Montelukast only:

Montelukast dosage: PO 10 mg QHS for 3 months arm 3: Non-smoking asthmatics treated with combination therapy:

Fluticasone propionate dosage - DPI 250 mcg BID for 3 months Salmeterol dosage - DPI 50 mcg BID for 3 months arm 4: Non-smoking asthmatic treated with Montelukast only:

Montelukast dosage: PO 10 mg QHS for 3 months arm 5: Normal controls

Interventions: intervention 1: Fluticasone Propionate intervention 2: Montelukast intervention 3: Salmeterol
Intervention descriptions: intervention 1: DPI 250 mcg BID for 3 weeks intervention 2: PO 10 mg QHS for 3 weeks intervention 3: DPI 50mg BID for 3 weeks

Protocol document: