Relationship between chronic obstructive pulmonary disease (COPD) assessment test score and prognostic factors of COPD patients / 第二军医大学学报

ABSTRACT

Objective To observe the correlation between chronic obstructive pulmonary disease (COPD) assessment test (CAT) score and prognostic factors, so as to investigate the value of CAT score in predicting the prognosis of COPD. Methods A total of 81 patients with newly diagnosed COPD in our hospital during Jul. 2011 to Sep. 2012, without using inhaled corticosteroid (ICS)/long-acting β2 agonist (LABA) or long-acting antimuscarinic agent (LAMA), were divided into group A (low risk, less symptoms), B (low risk, more symptoms), C (high risk, less symptoms) and D (high risk, more symptoms) groups according to Global Initiative for Chronic Obstructive Lung Disease (GOLD, 2011 edition), and the patients were given ICS/LABA or ICS/LABA+ LAMA treatment for 3 months. The CAT score, age, smoking quantity, pulmonary function indices, body mass index (BMI), 6-min walking distance (6MWD), modified medical British research council (mMRC) dyspnea scale, and the times of acute exacerbation of COPD (AECOPD) in previous one year were collected before and after treatment. The clinical characteristics analysis and correlation analysis were performed. Results The average age of the 81 COPD patients was (66.27±8.52) years, with 88.89% being males and 85.19% having smoking history. The proportions of group A, B, C and D were 8.64%, 30.86%, 4.94% and 55.56% before treatment, repectively. The values of the forced expiratory volumein one second (FEV1), predicted amount as a percentage of FEV1 (FEV1%Pred), forced vital capacity (FVC), predicted amount as a percentage of FVC (FVC% Pred), peak expiratory flow (PEF), predicted amount as a percentage of PEF (PEF%Pred), and 6MWD in CAT score ≥ 10 groups were significantly less than those in CAT score 10 group (P < 0. 05). The above parameterswere not significantly different between patients with CAT score being 10-20, 20-30 and ≥ 30 groups. mMRC scale and times of AECOPD in CAT score ≥20 groups were significantly higher than those in CAT score 10 group (P < 0. 05). No significant difference in FEV1/FVC was found in different CAT score groups. The CAT score was significantly correlated with mMRC scale (pre-treatment r2 = 0. 417, P lt; 0. 001; post-treatment r2 =0. 19, P < 0. 001), 6MWD (pretreatment r2 = 0. 320, P < 0. 001 post-treatment r2 = 0. 19, P < 0. 001), pre-treatment FEV1 (r2 = 0. 177, P = 0. 001 5), FEV1 %Pred(r2 = 0. 125, P = 0. 002), PEF(r2=0. 164, P = 0. 002 4), PEF%Pred (r2=0. 129, P = 0. 007 6), FVC (r2 = 0. 098, P=0. 021), FVC%Pred (r2 = 0. 094, P = 0. 024), FEV1/FVC(r2 = 0. 101, P = 0. 005 7), and AECOPD number (r2 = 0. 059, P = 0. 028); and not correlated with the quantity of smoking (r2 = 0. 041, P = 0. 083), BMI (r2 =0. 00, P = 0.89), and post-treatment FEV1 (r2 =0. 01, P = 0. 22) or FEV1 %Pred (r2 =0. 003, P = 0. 09). Conclusion COPD is prone to occur in the male smokers, with the highest proportion found in group D. CAT score has a good correlation with pre- and pos-- treatment mMRC scale and exercise capacity, suggesting it has a potential for predicting prognosis of COPD.