A three years longitudinal follow-up study of pulmonary function changes in patients with chronic obstructive pulmonary disease / 中华内科杂志

ABSTRACT

Objective To investigate the characteristics and the risk factors of pulmonary function in patients with chronic obstructive pulmonary disease (COPD) for a 3 year follow-up.Methods Subjects diagnosed as COPD were followed up for 3 years in the Management Center of Chronic Respiratory Disease at XINQIAO Hospital from September 2009 to June 2012.This was a retrospective study.Parameters related to respiratory function mainly first second forced expiratory volume (FEV1),COPD assessment test (CAT),6 minutes walking distance (6MWD) and acute exacerbation were recorded during follow-up.Results Although the majority of patients were treated with drugs such as inhaled corticosteroid combined with longterm bronchial dilatation during the three years,FEV1 decreased progressively.The average annual decline of FEV1 was(31.80 ± 61.99) ml,translating into a mean annual decline of(3.74 ± 6.18) ％.However,there were significant differences in changes of FEV1.Approximately,FEV1 in 78.3％ (47/60) patients decreased,only 21.7％ (13/60) patients kept stable FEV1.There was a correlation between decrease of FEV1,FEV1 ％ predicted and the exacerbation (r =0.298,0.361,0.273;P ＜ 0.05).Logistic regression showed that the positive bronchodilator reversibility and the initial FEV1 were the independent factors associated with significant changes in FEV1 (respectively,OR =5.54,95％ CI 1.55-19.73;OR =8.28,95％ CI 1.42-48.32).Conclusion The changes of pulmonary function in patients with COPD are heterogeneous,although most patients are treated in a standard way.Nearly 80％ patients still represent deterioration of pulmonary function.Decline of FEV1 is closely related to the initial pulmonary function and bronchodilator reversibility.