Methods: between January and December 2012, a total of 208 consecutive asthmatic adult patients (65% female), attending to out-patients clinic (Sezana) were involved in the study . The mean age was 55.4 ± 1.6 years. The diagnosis of asthma was assessed according to Global Initiative for Asthma (GINA) guidelines. Asthma control was assessed by Asthma Control Test (ACT). The residual volume expressed as percent of total lung capacity (TLC), RV/TLC% were measured.Predicted values for RV/TLC%(measured by full body plethysmography) were computed using the equations.Demographic criteria and smoking habits were also analysed.
Results: 35% of patients had changes in the small airways. The mean age was 59.4±1.5 years (51% female). Of them , 19.4% were active smokers and 1.3% were former smokers .11.5% patients without involvement of small airways diseases were active smokers and 0.7% former smokers.The average value for RV/TLC% was 147.5%±13.8.According to Asthma Control Test scores 60% of our patients without involvement of small airways disease had controlled asthma. The reverse situations were among the patients with small airways involvement.There were more patients in the not well controlled group 54%. 53% of patients with small airways involvement had exacerbations in this year (28% had one exacerbation, 20% two exacerbations and 5% three or more exacerbations). 21% of patients with not involvement of small airways had exacerbations ( 18% had one exacerbation , 2% two exacerbations and 1% three exacerbations).The number of asthmatic patients requiring hospitalization due to asthma in the investigated period was higher in the patients with small airways involvement(8%) than in the patients without small airways involvement (4%). 22.2% of patients with small airways disease and 12 % of patients with non small airways involvement had nocturnal asthma.
Conclusions: the results suggest that adult asthmatics with small airways involvement suffer from a more severe and less controlled asthma.