PT - JOURNAL ARTICLE AU - Li Hong-Lin AU - Hong Ping Zhang AU - Bing Miao Liang AU - Gang Wang TI - Does small-airways dysfunction predispose to greater perceived respiratory symptoms during bronchoconstriction in asthma? DP - 2014 Sep 01 TA - European Respiratory Journal PG - P1772 VI - 44 IP - Suppl 58 4099 - http://erj.ersjournals.com/content/44/Suppl_58/P1772.short 4100 - http://erj.ersjournals.com/content/44/Suppl_58/P1772.full SO - Eur Respir J2014 Sep 01; 44 AB - Background: Small-airways dysfunction(SAD) is associated with poor asthma control, but its mechanism is unclear. Our aim was to explore influence of SAD on respiratory symptoms during acute airway narrowing.Methods: Adult asthma patients with FEV1%≥80% (n=185) were consecutively recruited and followed by methacholine provocation test. Lung function (FEV1; MMEF and RV), ACQ, and AQLQ at baseline were assessed. Dyspnea intensity (Borg scale), qualitative descriptors of breathlessness and other respiratory symptoms (visual analogue scales, VAS) were measured at baseline and after provocation.Results: These patients were divided into four groups: MMEF≥65% and RV≥125.80% (group A), MMEF≥65% and RV<125.80% (group B); MMEF<65% and RV≥125.80% (group C), MMEF<65% and RV<125.80% (group D). The C group had the worst ACQ and AQLQ. The C group had increased dyspnea score (1.8±1.6) compared with the A (1.2±1.2), B (1.0±1.0) and D (1.1±1.2) groups at baseline (P=0.038). The B (19.6±18.7 and 23.4±18.2) and D (21.4±23.5 and 19.8±23.1) groups experienced greater VAS increase in chest tightness and cough than the A (9.9±14.4 and 12.8±21.9) and C (14.4±24.7 and 13.4±17.8) groups after provocation. Furthermore, the C and D groups displayed the higher frequency in some descriptors of breathlessness than others. MMEF was related to FEV1, Borg score, VAS increase of chest tightness, asthma duration and exacerbations. However, no relationship between MMEF and respiratory symptoms after adjusting for gender, asthma duration, baseline FEV1 and Borg score, PD20, and body mass index was found.Conclusions: It doesn't find SAD predisposes to greater respiratory symptoms.