Relations between airways closure and the recovery of symptom in patients with severe chronic obstructive pulmonary disease

Abstract

Objective To evaluate the contributions of airways closure on the improvement of symptom in patients with severe chronic obstructive pulmonary disease (COPD) when they receive drug treatent.Methods Seventy-seven patients with severe COPD (male 53,female 24) were enrolled from Jan.2012 to Sep.2012.,who were divided into group A(37 in grade C)and group B (40 in grade D) according the clinical standard in GOLD 2011.Salmeterol/Fluticasone 50/500 μg was delivered twice a day for 4 months.Spirometric were checked at their recritment and 2 months later for the measurement of the relative change of FVC(forced vital capacity) and FEV1 which reply the improvement of airways closure.Simutanusly,six-minute walk distance (6MWD) and scales including Chronic Obstructive Pulmonary Disease Assessment Test (CAT) and the measuring scales of dyspnea (MMRC) were completed.Results After therapy,all the measurments improve in some degree.The difference of △FVC/△FEV1 between the group A and B was not obvious (3.55± 1.15 vs 3.38± 1.23,z =-0.78,P ＞0.05),also that of △CAT between them (2.23± 1.32 vs 2.40± 1.43,t =0.78,P ＞0.05).But the difference of 6MWD between the two groups was obvious [(69± 53) m vs (52 ± 40) m,t =2.28,P ＜0.05)].△FVC/△FEV1 was positively correlative with△6MWD and △CAT (r is 0.702,0.685 respectivly,P ＜ 0.05).Conclusions The extent of the improvement of airways closure in COPD patients with grade C was the same as that in grade D.But the improvement of airways closure relates to symptom and exercise tolerance,the more improvement of airways closure,the more improvement of symptom and exercise tolerance.As a simple index,△FVC/△FEV1 hinting the escape of trapped gas and the improvement of symptom,deserves more investigations. Key words: Chronic obstructive pulmonary disease; △FVC/△FEV1; Chronic Obstructive Pulmonary Disease Assessment Test; Six-minute walk distance