The relationship of dyspnea and disease severity with anthropometric indicators of malnutrition among patients with chronic obstructive pulmonary disease

The effect of acupuncture on exercise capacity in patients with COPD is mediated by improvements of dyspnea and leg fatigue: a causal mediation analysis using data from a randomized controlled trial

BACKGROUND

Acupuncture is known to improve exercise capacity in patients with chronic obstructive pulmonary disease (COPD), but its mechanism remains unknown. Whether acupuncture improves exercise capacity in patients with COPD through alleviation of leg fatigue and dyspnea is examined by applying causal mediation analysis to previous trial data.

METHODS

Sixty-two patients with COPD completed treatments with either real or placebo acupuncture once a week for 12 weeks. Walk distance measured using the 6-minute walk test and intensities of leg fatigue and dyspnea in the modified Borg scale were evaluated at baseline and after treatment. The intervention effect of acupuncture against the placebo acupuncture on two mediators, changes in leg fatigue and dyspnea, and whether they mediated improvements in walk distance, were analyzed.

RESULTS

Linear regression analysis showed that the unstandardized regression coefficients [95% confidence interval (CI)] for the intervention effect by acupuncture were -4.9 (-5.8--4.0) in leg fatigue and -3.6 (-4.3--2.9) in dyspnea. Mediation analysis showed that when changes in leg fatigue were considered as a mediator, direct effect, indirect effect and proportion mediated were 47.1 m (95% CI, 4.6-85.1), 34.3 m (-2.1-82.1), and 42.1%, respectively, and when changes in dyspnea were considered as a mediator, they were 9.8 m (-32.9-49.9), 72.5 m (31.3-121.0), and 88.1%, respectively, and the effects of joint mediator were -5.8 m (-55.4-43.9), 88.9 m (32.7-148.5), and 107.0%, respectively.

CONCLUSION

The improvement in exercise capacity by acupuncture is explained by changes in both leg fatigue and dyspnea.

Determinants of Activity Phenotype in Patients with Chronic Obstructive Pulmonary Disease

Introduction

Physical activity (PA) and sedentary behavior (SB) have attracted attention in chronic obstructive pulmonary disease (COPD), and there have been efforts to evaluate PA and SB separately. The factors associated with the characteristics of the four activity phenotypes defined by the durations of PA and SB are largely unknown. The aim of this study was to clarify the factors that could differentiate each activity phenotype.

Materials and Methods

Study subjects were outpatients with stable COPD who were ≥40 years of age. We investigated the influence of 26 different factors on the activity phenotypes of COPD and extracted the factors that showed significant differences among the four activity phenotypes.

Results

Two hundred sixteen patients were included in the analysis. Exercise capacity and dyspnea were determinants that distinguished the low PA groups from the high PA groups. The pulmonary function and desaturation during exercise were factors that distinguished the high PA with low SB group from the low PA with high SB group. BMI, grip strength, upper arm circumference and HbA1c were higher in the low PA and low SB group than in the low PA and high SB group.

Conclusion

These factors could be the determinants discriminating activity phenotypes of patients with COPD.

AND-ASPEN and ESPEN consensus, and GLIM criteria for malnutrition identification in AECOPD patients: a longitudinal study comparing concurrent and predictive validity

BACKGROUND/OBJECTIVES

Malnutrition in chronic obstructive pulmonary disease (COPD) patients is prevalent and usually assessed by body mass index (BMI), which can lead to misdiagnosis. The subjective global assessment (SGA) is the reference method for this diagnose in hospitalized patients. In the last decade, new tools have emerged Academy of Nutrition and Dietetics-American Society for Parenteral and Enteral Nutrition [AND-ASPEN], European Society for Clinical Nutrition and Metabolism [ESPEN], and Global Leadership Initiative on Malnutrition [GLIM]). Therefore, this study aimed to assess the concurrent and predictive validity of these tools in acute exacerbated COPD (AECOPD) patients.

SUBJECTS/METHODS

Prospective cohort study with hospitalized AECOPD patients. Malnutrition was diagnosed by SGA (reference method), AND-ASPEN, ESPEN, and GLIM consensus. Hospital length of stay (LOS) and mortality were the outcomes evaluated.

RESULTS

In 241 patients (46.5% males; 68.3 ± 10.2 years), malnutrition was found in 50.0% by SGA, 54.4% by AND-ASPEN, 20.2% by ESPEN, and 47.8% by GLIM. AND-ASPEN had the best accuracy (AUC = 0.837; 95% CI 0.783-0.841) and concordance (kappa = 0.674) with SGA and it was an independent predictor of prolonged LOS (OR = 1.73; 95% CI 1.01-3.37). ESPEN consensus did not agree with SGA, but was associated with prolonged LOS (OR = 2.57 95% CI, 1.27-5.20). The GLIM had good concordance (kappa = 0.533) and accuracy with SGA (AUC = 0.768; 95% CI 0.701-0.835), but was not associated with outcomes.

CONCLUSIONS

The AND-ASPEN was the most accurate tool for diagnosing malnutrition in AECOPD patients and was an independent predictor of prolonged LOS.

Muscle mass and function are related to respiratory function in chronic obstructive pulmonary disease

Background: Chronic obstructive pulmonary disease (COPD), as an airway limitation condition, is accompanied by alteration of muscle mass and function. We aimed to determine the relationship between disease severity and body composition, muscle function, and nutritional status in COPD patients. Methods: This cross-sectional study was conducted on 129 COPD participants. Muscle strength, body composition, and calf circumference (CC) were measured using a hydraulic hand dynamometer, bioelectrical impedance analysis (BIA), and a tape measure, respectively. Furthermore, fat-free mass index (FFMI), body mass index (BMI) and muscle mass value were calculated by equations. Forced expiratory volume in one second (FEV1) was assessed as well. Nutritional status was also evaluated by subjective global assessment (SGA) questionnaire. SPSS software (version 21 ) was used, chi-square, fisher's exact test, univariate and multivariate linear regression models were used for statistical analysis. P-values less than 0.05 were considered significant. Results: Based on FEV1 classification, 52.7% of the patients had severe conditions. The reports indicated that the prevalence of low CC was 54.2%, low muscle mass 38.7%, low FFMI 34.8%, low right handgrip strength 61.2% and low left handgrip strength 64.3%. Furthermore, there was an increasing trend based on FEV1 in low CC (p=0.032), low muscle mass (p=0.005), low FFMI (p=0.002), low right handgrip strength (p=0.004) and low left handgrip strength (p=0.014). The results of univariate analysis showed muscle mass (p=0.036), total protein (p=0.043), FFM (p=0.047), FFMI (p=0.007), SGA (p=0.029), right handgrip strength (p=0.004) and left hand grip strength (p=0.023) were associated with FEV1. In addition, the results of multivariate analysis demonstrated low values of FFMI (p=0.005) and right handgrip strength (p=0.042) were the main detrimental factors for FEV1. The results of multivariate analysis were confirmed by stepwise model. Conclusion: Low values of muscle mass and function are prevalent among COPD patients. The present study revealed that low FFMI and handgrip strength were closely related to disease severity.

Respiratory Sarcopenia and Sarcopenic Respiratory Disability: Concepts, Diagnosis, and Treatment

The condition of muscle fiber atrophy and weakness that occurs in respiratory muscles along with systemic skeletal muscle with age is known as respiratory sarcopenia. The Japanese Working Group of Respiratory Sarcopenia of the Japanese Association of Rehabilitation Nutrition narratively reviews these areas, and proposes the concept and diagnostic criteria. We have defined respiratory sarcopenia as "whole-body sarcopenia and low respiratory muscle mass followed by low respiratory muscle strength and/or low respiratory function." Respiratory sarcopenia can be caused by various factors such as aging, decreased activity, undernutrition, disease, cachexia, and iatrogenic causes. We have also created an algorithm for diagnosing respiratory sarcopenia. Respiratory function decreases with age in healthy older people, along with low respiratory muscle mass and strength. We have created a new term, "Presbypnea," meaning a decline in respiratory function with aging. Minor functional respiratory disability due to aging, such as that indicated by a modified Medical Research Council level 1 (troubled by shortness of breath when hurrying or walking straight up hill), is an indicator of presbypnea. We also define sarcopenic respiratory disability as "a disability with deteriorated respiratory function that results from respiratory sarcopenia." Sarcopenic respiratory disability is diagnosed if respiratory sarcopenia is present with functional disability. Cases of respiratory sarcopenia without functional disability are diagnosed as "at risk of sarcopenic respiratory disability." Functional disability is defined as a modified Medical Research Council grade of 2 or more. Rehabilitation nutrition, treatment that combines rehabilitation and nutritional management, may be adequate to prevent and treat respiratory sarcopenia and sarcopenic respiratory disability.