Asthma diagnosis and treatment – 1008. Is small airways disease a widely prevalent yet underdiagnosed phenotype of asthma and COPD in India?

Results Data comprised 14 males, 35 females, mean age 54yrs (31-72), 82 % never-smokers. 44 had post bronchodilator studies. FEF75 or FEF25-75 < 65% were categorised as SAW disease. Pre bronchodilator (Pre-BD) Mean FEV1/ FVC was 78% (70-91%), however Mean FEF75 and FEF25-75 (% predicted) were 34.5% and 43.3% respectively. 6 patients had both, a reversibility in FEV1 >12% and increase by 200ml. Interestingly, of the remaining 38 patients who had no reversibility on a postbronchodilator study, 19 had > 30% reversibility in either FEF 25-75 or FEF75 (Mean reversibility of 53.5%) with a mean post bronchodilator increase in flow rates of 506.3 mL/s. All patients improved symptomatically with inhaled bronchodilator ± steroid therapy.