Characteristics of bronchial asthma with persistent airflow limitation

BACKGROUND: Asthma is a chronic inflammatory disorder of airway characterized by variable symptoms and variable airflow limitation. There are many patients developed persistent airflow limitation in due course of disease due to many factors. The present study was conducted to characterize this phenotype and to identify the factors which are implicated in causing persistent airflow limitation. MATERIALS AND METHODS: We recruited consecutive 164 patients aged <40 years (to exclude chronic obstructive pulmonary disease [COPD]), diagnosed, and treated as bronchial asthma in our asthma clinic for at least 6 months. We took all clinical, lung function detail and compared between asthma with or without persistent airflow limitation. The patients were assigned to the group with persistent airflow obstruction if they presented postbronchodilator forced expiratory volume in 1 s (FEV1) or FEV1/forced vital capacity values <70% predicted. RESULTS: A total of 114 patients included in the study and 42 (36.84%) patients had persistent airflow limitation. The patients with persistent airflow limitation have a higher age and more proportion of patients were male. History of allergic rhinitis is an important risk factor found associated with asthma with persistent airflow limitation (P≤ 0.001). 26.19% of patients with persistent airflow limitation had a history of symptom since childhood and generally having a longer disease duration compared to patient without airflow limitation (P < nonsignificant). Reversibility criteria (>12% and >200 ml increase in FEV1) was fulfilled by only 26.7% of the study patients. The factors such as onset of disease after 18 years, history of atopy, serum IgE level, family history of asthma, and biomass fuel exposure did not differ between groups with or without airflow limitation. CONCLUSIONS: Bronchial asthma is more having a COPD such as spirometry features if it has been started since childhood, longer disease duration, and history of allergic rhinitis. Reversibility in spirometry, which is specific for asthma diagnosis, is found only in one-fourth of the patients.