About one-fifth of patients with chronic obstructive pulmonary disease (COPD) in a newly reported study suffered from disease-related malnutrition, based on international diagnostic criteria, and half of patients with advanced disease were malnourished.
The cross-sectional analysis also showed a high rate of skeletal muscle mass loss in COPD patients based on international standard criteria.
The study, appearing in the journal Respiratory Medicine, is the first to provide data on the prevalence of malnutrition and sarcopenia among COPD patients using newly established criteria from the European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Working Group on Sarcopenia in Older People (EWGSOP).
“A relatively high prevalence of malnutrition and sarcopenia was found in COPD patients applying international standard criteria, with some discrepancy between the two diagnoses,” Francesca de Blasio, PhD, of Italy’s University of Naples Medical School, and colleagues, wrote. “In addition, clear-cut changes in raw bioimpedance analysis (BIA) variables were observed in malnourished patients with systemic inflammation and sarcopenia patients.”
Weight loss, poor nutrition, and sarcopenia are common disease-related features of advanced COPD which have important implications for the management of disease, but defining the diagnostic criteria for malnutrition or sarcopenia is widely debated, the researchers noted.
“A wide range of differences in the estimated prevalence of malnutrition in COPD has been reported in the literature, possibly due not only to the characteristics of patients (stages of the disease, exacerbations, etc.), but also to the use of different diagnostic approaches,” they wrote.
The researchers noted that in the clinical setting, fat-free mass (FEM) and skeletal muscle mass (SM) are commonly estimated in COPD patients using predictive equations that include bioimpedance analysis data. One objective of their study was to assess whether significant changes in raw BIA variables occur in the context of COPD-related malnutrition and/or sarcopenia.
The cross-sectional study included 263 patients with COPD (185 males and 78 females) who underwent both clinical examination and respiratory, anthropometric, bio-electrical impedance analysis (BIA raw variables: phase angle and impedance ratio), handgrip strength (HGS), 4-m gait speed and biochemical measurements while undergoing a comprehensive, inpatient 4-to-6 week pulmonary rehabilitation protocol.
Malnutrition and sarcopenia were diagnosed based on ESPEN and EWGSOP criteria, respectively.
All patients were 50 or older and had a baseline post-bronchodilator ratio of FEV1 to forced vital capacity of less than 0.7.
Among the main study findings:
- Overall prevalence of malnutrition and sarcopenia was 19.8% and 24.0%, respectively, and increasing with disease severity
- Prevalence of sarcopenia was significantly higher in patients with malnutrition (71.2% versus 12.3%; P<0.001), especially in those with cachexia (85.7% versus 61.3%; P<0.001)
- Malnourished patients with sarcopenia had a significant reduction in BMI, fat-free mass and HGS compared to non-sarcopenic patients
- Impedance ratio significantly increased and phase angle decreased in patients with severe sarcopenia and in cachectic patients
“Raw BIA variables (IR and phase angle) are altered in malnourished COPD patients, especially in those with cachexia (i.e., disease-related malnutrition with inflammation) or severe sarcopenia,” the researchers wrote. “BIA is a quick, non-invasive method to estimate body composition in the clinical setting, with the purpose to identify malnutrition and improve treatment (i.e., nutritional support and/or exercise rehabilitation).”
Lack of data on FFM or SM obtained with dual-energy x-ray absorptiometry (DXA) or other reference techniques was an important limitation, the researchers noted.
“Defining nutritional depletion and malnutrition should be of primary importance in both the clinical setting and management of COPD patients,” de Blasio and colleagues concluded.
“According to the results of the present study, there is a need for standardized and reproducible criteria in the diagnosis of malnutrition and sarcopenia in COPD. Within the group of malnourished patients, very clear differences emerged between patients with and without systemic inflammation with respect to raw BIA variables, i.e., IR and [phase angle]. Further research should further assess the applications of BIA for both clinical assessment of malnutrition and sarcopenia and the evaluation of the response to nutritional and/or pharmacological interventions.”
The researchers declared no relevant relationships with industry related to this study.
Robert Jasmer, MD Associate Clinical Professor of Medicine, University of California, San Francisco and Dorothy Caputo, MA, BSN, RN, Nurse Planner