PURPOSE: Chronic obstructive pulmonary disease (COPD) is a major cause of chronic morbidity and mortality throughout the world. According to the Global Burden of Disease Study, COPD was the sixth leading cause of death and the 12th leading cause of morbidity worldwide in 1990.
METHODS: Large nationwide COPD prevalence survey was performed in Korea in 2001. In the 246,079 sampling areas, 200 survey areas are randomly selected. The questionnaire survey on physician diagnosed diseases with respiratory symptoms was performed and spirometry was performed by trained technicians, using a same dry rolling seal spirometer.
RESULTS: Airway obstruction was defined by GOLD criteria. By GOLD criteria, 16.2% had obstructive lung disease in the participants older than 45 years old. However about half of the subjects had mild disease (9.5% in the participants older than 45 years old). The prevalence of respiratory symptoms in the mild COPD patients was significantly lower than in the moderate and severe COPD patients (chronic sputum 3.4% vs 12.0% respectively; P < 0.05, chronic cough 2.7% vs 10.4% respectively; P < 0.05). In the mild COPD patients, diagnostic rate was also low. The prevalence of current smoking was 42.5% in mild groups and 44.8% in moderate and severe groups, respectively (P<0.05).
CONCLUSION: By GOLD criteria, about half of the COPD patient had a mild disease. The prevalence of respiratory symptoms and diagnostic rate were lower in mild COPD patients, but smoking rate was not lower than in the moderate and severe COPD patients.
CLINICAL IMPLICATIONS: As the Characteristics of mild COPD were different from moderate and severe COPD patients, long term follow up is needed.
DISCLOSURE: Jae Hee Jeong, None.