The prognostic role of resting pulmonary hyperinflation as measured by residual volume (RV)/total lung capacity (TLC) in chronic obstructive pulmonary disease (COPD) remains poorly understood. Therefore, this study aimed to identify the factors related to resting pulmonary hyperinflation in COPD and to determine whether resting pulmonary hyperinflation is a prognostic factor in COPD. In total, 353 patients with COPD in the Korean Obstructive Lung Disease cohort recruited from 16 hospitals were enrolled. Resting pulmonary hyperinflation was defined as RV/TLC > or = 40%. Multivariate logistic regression analysis demonstrated that older age (P = 0.001), lower forced expiratory volume in 1 second (FEV1) (P < 0.001), higher St. George Respiratory Questionnaire (SGRQ) score (P = 0.019), and higher emphysema index (P = 0.010) were associated independently with resting hyperinflation. Multivariate Cox regression model that included age, gender, dyspnea scale, SGRQ, RV/TLC, and 6-min walking distance revealed that an older age (HR = 1.07, P = 0.027), a higher RV/TLC (HR = 1.04, P = 0.025), and a shorter 6-min walking distance (HR = 0.99, P < 0.001) were independent predictors of all-cause mortality. Our data showed that older age, higher emphysema index, higher SGRQ score, and lower FEV1 were associated independently with resting pulmonary hyperinflation in COPD. RV/TLC is an independent risk factor for all-cause mortality in COPD.
Aged ; Dyspnea/diagnosis/physiopathology ; Exercise Test ; Exercise Tolerance ; Female ; Forced Expiratory Flow Rates/physiology ; Forced Expiratory Volume ; Humans ; Lung/*physiopathology ; Male ; Middle Aged ; Prognosis ; Pulmonary Disease, Chronic Obstructive/*diagnosis/mortality/physiopathology ; Pulmonary Emphysema/*diagnosis/mortality/physiopathology ; Republic of Korea ; Residual Volume/*physiology ; Respiratory Function Tests ; Surveys and Questionnaires ; Total Lung Capacity/*physiology ; Vital Capacity ; Walking/physiology

BACKGROUND/AIMS: Many studies have investigated angina and its relationship with chronic obstructive pulmonary disease (COPD). However, angina was diagnosed only by noninvasive tests or only by clinical symptoms in most of these studies. The aim of this study was to compare the prognosis, including rate of hospitalization and death from significant coronary artery lesion and nonsignificant coronary artery lesion angina, in patients with COPD. METHODS: Patients with COPD who underwent coronary angiography (CAG) due to angina were reviewed retrospectively at a tertiary referral hospital. COPD is defined as post-bronchodilator forced expiratory volume in 1 sec/forced vital capacity (FEV1/FVC) of < 70%. A significant coronary lesion is defined as at least 50% diameter stenosis of one major epicardial artery in CAG. RESULTS: In total, 113 patients were enrolled. Mean follow-up duration was 39 +/- 21 months. Of the patients, 52 (46%) had mild COPD and 48 (42%) had moderate COPD. Sixty-nine (61%) patients had significant stenosis in CAG. The death rate in the follow-up period was 2.21 per 100 patient-years. No significant difference was observed among the all-cause mortality rate, admission rate, or intensive care unit admission rate in patients who had COPD with or without significant coronary artery disease. Pneumonia or acute exacerbation of COPD was the most common cause of admission. CONCLUSIONS: In patients having COPD with angina who underwent CAG, no significant difference was observed in mortality or admission events depending on the presence of a significant coronary artery lesion during the 2-year follow-up period.
Aged ; Angina Pectoris/*etiology ; Chi-Square Distribution ; Coronary Angiography ; Coronary Stenosis/*complications/mortality/radiography ; Female ; Forced Expiratory Volume ; Hospitalization ; Humans ; Kaplan-Meier Estimate ; Lung/physiopathology ; Male ; Middle Aged ; Prognosis ; Pulmonary Disease, Chronic Obstructive/*complications/diagnosis/mortality/physiopathology ; Republic of Korea ; Retrospective Studies ; Risk Assessment ; Risk Factors ; Severity of Illness Index ; Spirometry ; Time Factors ; Vital Capacity