Prevalence of chronic obstructive lung disease in Korea using data from the fifth Korea national health and nutrition examination survey

Chronic obstructive pulmonary disease (COPD) is the fifth leading cause of death worldwide. The awareness and treatment rate of the disease are low despite its relatively high prevalence. With the added data, this study aimed to identify changes in prevalence and risk factors of COPD using the data from the 5th KNHNES. The subjects of this study were 8,969 individuals aged 40 and older who satisfied suitability and reproducibility for pulmonary function tests. The prevalence, awareness and risk factors of COPD were predicted based on the questionnaires on gender, age, educational level, income level, smoking history, body mass index (BMI) and other COPD related questions. Diagnosis of COPD was based on the airflow limitation (forced expiratory volume in one second/forced vital capacity