Malnutrition in Japanese patients with chronic obstructive pulmonary disease: A prospective cohort study

Malnutrition is a common condition in patients with chronic obstructive pulmonary disease (COPD) and is associated with impaired lung function, worsened dyspnea, increased exacerbations, and higher mortality. However, diagnostic criteria for malnutrition have not been consistent. The Global Leadership Initiative on Malnutrition criteria were recently introduced to standardize the diagnosis of malnutrition. This study aimed to evaluate the prevalence, characteristics, and outcomes of malnutrition according to low body mass index of the Global Leadership Initiative on Malnutrition criteria in Japanese patients with COPD. A prospective observational study was conducted among Japanese patients with COPD from April 2018 to September 2024. Patient characteristics, exacerbation frequency, and mortality were assessed over a 5-year follow-up period. The odds ratios (ORs) for exacerbations were estimated using logistic regression analysis. A Cox proportional hazards model was used to examine the association between malnutrition and mortality. Among 309 patients (294 males, 15 females; median age, 76 years) with stable COPD, 14.5% were diagnosed with malnutrition. Patients diagnosed with malnutrition had a higher median age and showed greater airflow obstruction, more severe dyspnea, worsened health status, depressive state, muscle weakness, reduced exercise capacity, and lower physical activity compared with those who without malnutrition (all P < .05). Malnourished patients had a higher risk of exacerbations, including hospital admissions, compared with well-nourished patients (OR, 2.7, 95% confidence interval [CI], 1.2-5.9; and OR, 3.6, 95% CI, 1.5-8.7, respectively). All-cause and respiratory-associated mortality were significantly higher in malnourished patients than those without malnutrition (43.6% vs 19.1%, and 10.3% vs 2.5%, respectively; both P < .01). The adjusted hazard ratio for all-cause mortality in malnourished patients was 2.3 (95% CI, 1.3-4.2). Malnutrition is associated with adverse outcomes in Japanese patients with COPD, emphasizing the need for timely diagnosis and management.