Predictors of undernutrition in COPD patients

Abstract

Chronic obstructive pulmonary disease (COPD) is a chronic disease characterized by persistent respiratory symptoms and airflow limitation. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) report recommends smoking cessation, pharmacological therapy and pulmonary rehabilitation, but this clinical course can be negatively influenced by undernutrition, a condition documented in about 20% of COPD patients. An altered energy balance characterized by an insufficient intake of energy and nutrients is the primary cause of undernutrition, therefore the aim of this study is to investigate whether clinical and instrumental variables collected during a routine respiratory assessment associate with an altered energy balance in order to identify COPD patients at higher risk of undernutrition worth of further assessment. A total of forty-nine participants with a diagnosis of stable COPD were included in this mono-center and longitudinal study. Subjects underwent a multidimensional assessment including evaluation of medical history, evaluation of pulmonary function, evaluation of nutritional status, evaluation of energy intake and resting energy expenditure (REE) using EPIC questionnaire and indirect-calorimetry (IC), respectively, evaluation of physical impairment and mood status. The 24% of participants was at risk of undernutrition with a mean energy intake, total protein intake and lipid intake significantly lower than not at risk subjects, while REE was significantly higher. Age, sex, multimorbidity, disability and depression, and pulmonary function tests were not associated with a negative energy balance, with the exception of the Cumulative Illness Rating Scale (CIRS) severity index, which showed a significant association. Clinical evaluation and pulmonary function tests are unable to reliably predict undernutrition in COPD patients, so a nutritional screening should always be forecast in this population based on an accurate evaluation of energy intake and expenditure and body composition.