Smoking occurs frequently in patients with asthma. Recent surveys on smoking prevalence report 21-26% current smokers in populations of patients with asthma. Detrimental effects of active smoking in asthma include worse asthma control, an impaired response to corticosteroids and accelerated lung function decline.

The mechanisms by which cigarette smoking contributes to disease severity in asthma are incompletely understood, but it has been suggested that cigarette smoking may change inflammation and airway remodelling in asthma to become more similar to that in COPD (chronic obstructive pulmonary disease).

Any form of tobacco use, especially cigarette smoking, plays an important role in this disease. Asthmatic smokers are prone to several negative outcomes. Cigarette smoking by itself is associated with airway inflammation and features of airway remodelling including increased epithelial proliferation, squamous cell metaplasia, goblet cell hyperplasia, smooth muscle hypertrophy, and increases in bronchial glands mass.

Corticosteroid insensitivity is an important clinical feature of asthma, particularly in patients with severe disease and smokers. The mechanisms of corticosteroid insensitivity in asthmatic patients are poorly understood.

One of the major problems in the treatment of smoking asthma patients is the lack of efficacy data in this group of patients as smokers have almost always been excluded from studies on asthma due to perceived concerns about recruiting patients with COPD. Therefore, there is a lack of specific information about the treatment of asthma in smokers. The asthmatic smoker is a special phenotype with important therapeutic and prognostic clinical implications.

Inclusion criteria:

1. Stable asthmatic patients (however smokers, or non-smokers) will be included (stable asthmatic defined as no emergency clinic or hospital visit, oral corticosteroid prescription, or change in asthma treatment in the past month) and (Current smoking was defined as 5 or more cigarettes per day and a smoking history of 5 pack years or greater).
2. Treatment with long-acting b2-agonists, and leukotriene receptor antagonists was allowed.

Exclusion criteria:

1. Acute severe asthma.
2. Causes of airway obstruction other than asthma as COPD patients, bronchiectasis……etc.
3. Age <18 and >45 years old.
4. Body mass index >35.
5. Requirement for treatment with or the presence of conditions likely to be exacerbated by oral corticosteroids
6. The intention to stop smoking. Eligibility for the study required demonstration of reversible airflow obstruction (FEV1 bronchodilator response to b2 agonist of >12% [and >200 mL]) or a positive methacholine test result. All lung function assessments met relevant international consensus guidelines.

Stable asthmatic patients (however smokers, or non-smokers) will be included (stable asthmatic defined as no emergency clinic or hospital visit, oral corticosteroid prescription, or change in asthma treatment in the past month) and (Current smoking was defined as 5 or more cigarettes per day and a smoking history of 5 pack years or greater).