Poor nutritional intake is a dominant factor for weight loss in chronic obstructive pulmonary disease

: SETTING Increase in energy expenditure and/or decrease in nutritional intake leads to low body mass index (BMI). The balance between energy expenditure and nutritional intake has rarely been evaluated in a large population of patients with chronic obstructive pulmonary disease (COPD). OBJECTIVE To evaluate BMI, nutritional intake and physical activity and the association of these factors with the severity of airflow obstruction in COPD patients. DESIGN We analysed the Korean National Health and Nutrition Examination Survey (KNHANES) data set from 2012 to 2015. RESULTS Among the 9682 individuals (1601 with COPD and 8081 without COPD) recruited, BMI was lower in COPD patients than in non-COPD participants (males, 23.86 ± 2.76 vs. 24.28 ± 2.80, P CONCLUSION Patients with COPD had a low nutritional intake with little physical activity, which worsened with advancing COPD stage. In late-stage COPD, impaired nutritional intake outweighed the decrease in physical activity, resulting in weight loss. .