Uncovering undernutrition in chronic obstructive pulmonary disease: Beyond body mass index

Undernutrition, a common but treatable complication of chronic obstructive pulmonary disease (COPD), contributes to poor outcomes but is under-detected. Improved detection could prompt dietary intervention which may improve outcomes. We investigated whether adding a measure of muscle mass (fat-free mass index, FFMI) or a malnutrition screening tool (Mini Nutritional Assessment, MNA®) to the commonly used measure of body mass index (BMI), helps detect undernutrition in COPD.

We conducted a retrospective chart review of 86 outpatients with COPD. Demographic and disease severity data were collected, and nutritional status assessed using BMI, FFMI and MNA®.

Patients comprised 55% males with median age 71.5 years, severe COPD (median FEV₁ = 0.74 (30.5% predicted)) and high symptom impact (median COPD Assessment Test (CAT) = 23). Twenty-eight percent of patients had low BMI, 27% had low FFMI, 22% were MNA®-classified malnourished and 43% were MNA®-classified at risk of malnutrition. MNA® correlated moderately with BMI and classified 55% of patients with healthy/high BMI as either malnourished or at risk of malnutrition. FFMI and BMI correlated strongly, and low FFMI was present in 5% of patients with healthy/high BMI. The undernutrition measures also showed weak to moderate correlations with disease severity (spirometry data) and MNA® weakly correlated with symptom impact (CAT).

The MNA® identified more undernourished patients than FFMI or BMI. It also correlated with disease severity and broader symptom burden. The MNA® appears to be a simple tool for earlier detection of patients who may benefit from dietary intervention, potentially enhancing their quality of life.