RT Journal Article SR Electronic T1 Prevalence of hyperinflation and its reversibility in asthma patients with poorly controlled disease or significant dyspnea JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP P2252 VO 40 IS Suppl 56 A1 Thierry Perez A1 Pascal Chanez A1 Daniel Dusser A1 Daniel Vesque A1 Philippe Devillier YR 2012 UL http://erj.ersjournals.com/content/40/Suppl_56/P2252.abstract AB Introduction: Inflammation in asthma involves proximal and distal airways. The latter may induce a significant hyperinflation (HI).Aim: To evaluate the prevalence of HI by body plethysmography in asthmatic patients with poorly controlled disease and/or significant dyspnea.Methods: In 324 patients (age 49 ± 17; FEV1 75 ± 18 % pred) insufficient asthma control was defined by an ACT score < 20 (n = 302) or a significant dyspnea by a MRC score ≥ 1 (n=22).HI was defined by either a RV > pred + 1.64 RSD (=RV-HI) or a FRC > 120 % pred (= FRC-HI). HI reversibility after bronchodilator was defined by a decrease of RV > 20 % or a reduction of FRC > 10 % from baseline. Change in dyspnea and chest tightness were evaluated by a VAS.Results: HI was found in 49 % (RV-HI) and 47 % (FRC-HI) of cases. Prevalence of HI was higher in patients with a FEV1 < 60 % pred than in those with a FEV1 > 80 % pred: 78 % for RV-HI and 70 % for FRC-HI, vs 34 % and 40 %, respectively. ACT score was lower in patients with FRC-HI (13.4 ± 4 vs 14.6 ± 4; p = 0.004). Post-bronchodilator change was -10 ± 13 % for FRC, and - 12 ± 21 % for RV. HI reversibility was obtained in 59 % of cases with RV-HI and 47 % of cases with FRC-HI. Chest tightness decrease after bronchodilator was greater in patients with baseline FRC-HI (- 44 ± 25 vs - 37 ± 24 mm, p = 0.02). Dyspnea improvement was higher in those with baseline RV-HI (- 45 ± 26 mm vs - 38 ± 23, p = 0.02).Conclusion: Hyperinflation is frequent in poorly controlled asthma, including patients with normal FEV1, suggesting an involvement of distal airways. It appearsreversible in more than half of cases.