Pathophysiology of Respiration

R. Rubinsztajn, T. Przybyłowski, M. Maskey-Warzęchowska, K. Karwat, R. Chazan

Exacerbations of chronic obstructive pulmonary disease (COPD) are one of the most important factors which influence the course of disease and quality of life in COPD patients. The aim of the study was to assess the exacerbation frequency in COPD patients in relation to COPD severity and to evaluate the impact of the number of exacerbations on quality of life. The study included 445 COPD patients in all four progressive stages of the disease according to GOLD classification. The patients recorded exacerbations in diaries. Spirometry, St. George's Respiratory Questionnaire, and dyspnea score were assessed at baseline and after 12 and 24 months from enrollment. After 24 months, 261 diaries were returned. The mean number of exacerbations per year in the sequential GOLD 1-4 stages of COPD was as follows: 1.3 ± 2.1, 1.4 ± 2.0, 1.7 ± 1.8, and 3.4 ± 4.5. A statistical difference in the exacerbation frequency was noted for GOLD 4 and the remaining groups. A significant negative correlation was found between the number of exacerbations and functional status for GOLD 2 and 3 stages. We conclude that the number of exacerbations is the highest in the most severe stage of the disease. The quality of life of patients with moderate and severe COPD correlates negatively with the number of exacerbations.