Body composition changes in male patients with chronic obstructive pulmonary disease: Aging or disease process?

Muscle loss phenotype in COPD is associated with adverse outcomes in the UK Biobank

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disorder with systemic consequences that can cause a muscle loss phenotype (MLP), which is characterized by the loss of muscle mass, muscle strength, or loss of both muscle and fat mass. There are limited data comparing the individual traits of MLP with clinical outcomes in a large unbiased cohort of COPD patients. Our aim was to determine the proportion of patients who met criteria for MLP in an unbiased sample of COPD patients at the population-level. We also determined if specific MLP features were associated with all-cause and COPD-related mortality.

METHODS

A retrospective population-based cohort analysis of the UK Biobank was performed. COPD was defined by a FEV1/FVC ratio < 0.7, physician established diagnosis of COPD, or those with a COPD-related hospitalization before baseline assessment. MLP included one or more of the following: 1) Low fat-free mass index (FFMI) on bioelectric impedance analysis (BIA) or 2) Appendicular skeletal muscle index (ASMI) on BIA, 3) Low muscle strength defined by handgrip strength (HGS), or 4) Low muscle and fat mass based on body mass index (BMI). Cox regression was used to determine the association between MLP and all-cause or COPD-related mortality. All models were adjusted for sex, age at assessment, ethnicity, BMI, alcohol use, smoking status, prior cancer diagnosis and FEV1/FVC ratio.

RESULTS

There were 55,782 subjects (56% male) with COPD followed for a median of 70.1 months with a mean(± SD) age at assessment of 59 ± 7.5 years, and FEV1% of 79.2 ± 18.5. Most subjects had mild (50.4%) or moderate (42.8%) COPD. Many patients had evidence of a MLP, which was present in 53.4% of COPD patients (34% by ASMI, 26% by HGS). Of the 5,608 deaths in patients diagnosed with COPD, 907 were COPD-related. After multivariate adjustment, COPD subjects with MLP had a 30% higher hazard-ratio for all-cause death and 70% higher hazard-ratio for COPD-related death.

CONCLUSIONS

Evidence of MLP is common in a large population-based cohort of COPD and is associated with higher risk for all-cause and COPD-related mortality.

Identification of genes and key pathways underlying the pathophysiological association between sarcopenia and chronic obstructive pulmonary disease

PURPOSE

Chronic obstructive pulmonary disease (COPD) patients are likely to develop sarcopenia, while the exact mechanism underlying the association between sarcopenia and COPD is still not clear. This cohort study aims to explore the genes, signaling pathways, and transcription factors (TFs) that are related to the molecular pathogenesis of sarcopenia and COPD.

METHODS

According to the strict inclusion criteria, two gene sets (GSE8479 for sarcopenia and GSE76925 for COPD) were obtained from the Gene Expression Omnibus (GEO) platform. Overlapping differentially expressed genes (DEGs) in sarcopenia and COPD were detected, and comprehensive bioinformatics analysis was conducted, including functional annotation, enrichment analysis of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), construction of a protein-protein interaction (PPI) network, co-expression analysis, identification and validation of hub genes, and TFs prediction and verification.

RESULTS

In total, 118 downregulated and 92 upregulated common DEGs were detected. Functional analysis revealed that potential pathogenesis involves oxidoreductase activity and ferroptosis. Thirty hub genes were detected, and ATP metabolic process and oxidative phosphorylation were identified to be closely related to the hub genes. Validation analysis revealed that SAA1, C3, and ACSS2 were significantly upregulated, whereas ATF4, PPARGC1A, and MCTS1 were markedly downregulated in both sarcopenia and COPD. In addition, six TFs (NFKB1, RELA, IRF7, SP1, MYC, and JUN) were identified to regulate the expression of these genes, and SAA1 was found to be coregulated by NFKB1 and RELA.

CONCLUSION

This study uncovers potential common mechanisms of COPD complicated by sarcopenia. The hub gene SAA1 and the NF-κB signaling pathway could be involved, and oxidative phosphorylation and ferroptosis might be important contributors to this comorbidity.

Association of pectoralis muscle area on computed tomography with airflow limitation severity and respiratory outcomes in COPD: A population-based prospective cohort study

BACKGROUND

Previous studies have shown that patients with chronic obstructive pulmonary disease (COPD) of severe or very severe airflow limitation have a reduced pectoralis muscle area (PMA), which is associated with mortality. However, whether patients with COPD of mild or moderate airflow limitation also have a reduced PMA remains unclear. Additionally, limited evidence is available regarding the associations between PMA and respiratory symptoms, lung function, computed tomography (CT) imaging, lung function decline, and exacerbations. Therefore, we conducted this study to evaluate the presence of PMA reduction in COPD and to clarify its associations with the referred variables.

METHODS

This study was based on the subjects enrolled from July 2019 to December 2020 in the Early Chronic Obstructive Pulmonary Disease (ECOPD) study. Data including questionnaire, lung function, and CT imaging were collected. The PMA was quantified on full-inspiratory CT at the aortic arch level using predefined -50 and 90 Hounsfield unit attenuation ranges. Multivariate linear regression analyses were performed to assess the association between the PMA and airflow limitation severity, respiratory symptoms, lung function, emphysema, air trapping, and the annual decline in lung function. Cox proportional hazards analysis and Poisson regression analysis were used to evaluate the PMA and exacerbations after adjustment.

RESULTS

We included 1352 subjects at baseline (667 with normal spirometry, 685 with spirometry-defined COPD). The PMA was monotonically lower with progressive airflow limitation severity of COPD after adjusting for confounders (vs. normal spirometry; Global Initiative for Chronic Obstructive Lung Disease [GOLD] 1: β=-1.27, P=0.028; GOLD 2: β=-2.29, P<0.001; GOLD 3: β=-4.88, P<0.001; GOLD 4: β=-6.47, P=0.014). The PMA was negatively associated with the modified British Medical Research Council dyspnea scale (β=-0.005, P=0.026), COPD Assessment Test score (β=-0.06, P=0.001), emphysema (β=-0.07, P<0.001), and air trapping (β=-0.24, P<0.001) after adjustment. The PMA was positively associated with lung function (all P<0.05). Similar associations were discovered for the pectoralis major muscle area and pectoralis minor muscle area. After the 1-year follow-up, the PMA was associated with the annual decline in the post-bronchodilator forced expiratory volume in 1 s percent of predicted value (β=0.022, P=0.002) but not with the annual rate of exacerbations or the time to first exacerbation.

CONCLUSION

Patients with mild or moderate airflow limitation exhibit a reduced PMA. The PMA is associated with airflow limitation severity, respiratory symptoms, lung function, emphysema, and air trapping, suggesting that PMA measurement can assist with COPD assessment.

Physical Activity, Exercise Capacity, and Body Composition in U.S. Veterans with Chronic Obstructive Pulmonary Disease (COPD)

RATIONALE

Differences in body composition may contribute to variability in exercise capacity (EC) and physical activity (PA) in chronic obstructive pulmonary disease (COPD). Most studies have employed bioimpedance-based surrogates of muscle (lean) mass; relatively few studies have included consideration of fat mass and limited studies have been performed using dual X-ray absorptiometry (DXA)-assessed body composition.

OBJECTIVE

To determine whether DXA-assessed muscle (lean) and fat mass exhibit differential correlations with EC and PA in COPD Methods: US Veterans with COPD (defined as FEV1/FVC<0.7 or emphysema on clinical chest computed tomography) had DXA-assessed body composition, EC (6-minute walk distance; 6MWD), objective PA (average daily step counts), and self-reported PA measured at enrollment. Associations between EC, PA, and body composition were examined using Spearman correlations and multivariable models adjusted a priori for age, sex, race, and lung function.

RESULTS

Subjects (n=98) were predominantly white (88%), obese (mean BMI 30.2±6.2), and male, (94%) with a mean age (±SD) of 69.9±7.9 years and moderate airflow obstruction (mean FEV1% 68±20). Modest inverse correlations between EC and PA with fat mass were observed (Spearman's rho range [-0.20]-[-0.34]) while measures of muscle (lean) mass were not significantly associated with EC or PA. The appendicular skeletal muscle (ASM)-to-weight ratio, which considers both muscle (lean) and fat mass, was consistently associated with EC (8.4 [95%CI=2.9-13.8] meter increase on 6MWD per 1% increase in ASM-to-weight ratio), objective PA (194.8 [95%CI=15.2-374.4] steps per day per 1% increase in ASM-to-weight ratio), and self-reported PA in multivariable-adjusted models.

CONCLUSION

DXA-assessed body composition measures which include consideration of both lean and fat mass are associated with cross-sectional EC and PA in COPD populations. Clinical trial registered at ClinicalTrials.gov (NCT02099799).

Prediction of Sarcopenia Using Multiple Biomarkers of Neuromuscular Junction Degeneration in Chronic Obstructive Pulmonary Disease

Patients with chronic obstructive pulmonary disease (COPD) present with an advanced form of age-related muscle loss or sarcopenia. Among multiple pathomechanisms of sarcopenia, neuromuscular junction (NMJ) degradation may be of primary relevance. We evaluated the circulating biomarkers of NMJ degradation, including c-terminal agrin fragment -22 (CAF22), brain-derived neurotrophic factor (BDNF), and glial cell line-derived neurotrophic factor (GDNF) as predictors of sarcopenia in COPD during pulmonary rehabilitation (PR). Male, 61-77-year-old healthy controls and patients of COPD (n = 77-84/group) were recruited for measurements of circulating CAF22, BDNF, and GDNF levels. Functional assessment and measurements of plasma biomarkers were performed at diagnosis and following six months of PR. CAF22 levels were elevated while BDNF and GDNF levels were reduced in COPD patients at diagnosis, which were incompletely restored to normal levels following PR. These biomarkers showed varying degrees of associations with indexes of sarcopenia and functional recovery during PR. Logistic regression revealed that the combined use of three biomarkers enhanced the diagnostic accuracy of sarcopenia better than single biomarkers. Altogether, measurements of plasma CAF22, BDNF, and GDNF may be helpful for the accurate diagnosis of sarcopenia and functional capacity in COPD during PR.

Mortality and Exacerbation Risk by Body Mass Index in Patients with COPD in TIOSPIR® and UPLIFT®

Rationale

There is an association between body mass index (BMI) and mortality in chronic obstructive pulmonary disease (COPD), with underweight individuals having higher mortality risk. Mortality and exacerbation risks among individuals with higher BMI are unclear.

Objectives

To examine the relationship between BMI and adverse outcomes in COPD.

Methods

This post hoc analysis included data from TIOSPIR (Tiotropium Safety and Performance in Respimat) (N = 17,116) and tiotropium-treated patients in UPLIFT (Understanding Potential Long-term Impacts on Function with Tiotropium) (N = 2,986). BMI classes (underweight [BMI < 20 kg/m²], normal weight [BMI 20 to <25 kg/m²], overweight [BMI 25 to <30 kg/m²], obesity class I [BMI 30 to <35 kg/m²], obesity class II [BMI 35 to <40 kg/m²], and obesity class III [BMI ⩾ 40 kg/m²]) were examined for adjusted associations with mortality, exacerbation, and nonfatal cardiovascular event risk using over 50,000 patient-years of cumulative follow-up data. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox regression models.

Results

In TIOSPIR, obesity prevalence was 22%, overweight 32%, and underweight 12%. The proportion of females was highest in obesity classes II and III. Overweight and obese participants had better baseline lung function versus other BMI classes; underweight participants were more likely to be current smokers. Underweight participants had a significantly higher risk of death (HR, 1.88; 95% CI, 1.62–2.20; P < 0.0001) and severe exacerbations (HR, 1.31; 95% CI, 1.16–1.47; P < 0.0001) versus normal-weight participants; however, overweight and obese participants were at lower to no additional risk. Results from UPLIFT were similar to TIOSPIR.

Conclusions

These results suggest that there is a strong association between body weight, COPD events, and risk of death. A holistic management approach taking into account respiratory and cardiovascular risk factors and nutritional status is needed to improve the general well-being of patients with COPD.

Longitudinal changes in total and regional body composition in patients with chronic obstructive pulmonary disease

Background and objective

Low fat‐free mass (FFM) is common in patients with chronic obstructive pulmonary disease (COPD) and contributes to morbidity and mortality. Few studies have evaluated longitudinal changes in body composition in patients with COPD compared with non‐COPD controls. This study aimed to compare longitudinal changes in total and regional body composition between patients with COPD and non‐COPD controls and investigate predictors of changes in body composition in COPD.

Methods

Patients with COPD and non‐COPD controls participating in the Individualized COPD Evaluation in relation to Ageing (ICE‐Age) study, a single‐centre, longitudinal, observational study, were included. Subjects were assessed at baseline and after 2 years of follow‐up. Among other procedures, body composition was measured by dual‐energy X‐ray absorptiometry scan. The number of exacerbations/hospitalizations 1 year before inclusion and during follow‐up were assessed in patients with COPD.

Results

A total of 405 subjects were included (205 COPD, 87 smoking and 113 non‐smoking controls). Patients with COPD and smoking controls presented a significant decline in total FFM (mean [95% CI]: −1173 [−1527/−820] g and −486 [−816/−156] g, respectively) while body composition remained stable in non‐smoking controls. In patients with COPD, the decline in FFM was more pronounced in legs (−174 [−361/14] g) and trunk (−675 [−944/406] g) rather than in arms (54 [−19/126] g). The predictors of changes in total and regional FFM in patients with COPD were gender, number of previous hospitalizations, baseline values of FFM and BMI.

Conclusion

Patients with COPD present a significant decline in FFM after 2 years of follow‐up, this decline is more pronounced in their legs and trunk.

Patients with chronic obstructive pulmonary disease (COPD) present a significant decline in total, leg and trunk low fat‐free mass (FFM), while arms FFM remains stable after 2 years of follow‐up. We identified a subgroup of patients with preserved FFM at baseline and history of previous hospitalizations that present greater decline in total and leg FFM compared to other patients with COPD.

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The product of trunk muscle area and density on the CT image is a good indicator of energy expenditure in patients with or at risk for COPD

Background

Physical inactivity due to cachexia and muscle wasting is well recognized as a sign of poor prognosis in chronic obstructive pulmonary disease (COPD). However, there have been no reports on the relationship between trunk muscle measurements and energy expenditure parameters, such as the total energy expenditure (TEE) and physical activity level (PAL), in COPD. In this study, we investigated the associations of computed tomography (CT)-derived muscle area and density measurements with clinical parameters, including TEE and PAL, in patients with or at risk for COPD, and examined whether these muscle measurements serve as an indicator of TEE and PAL.

Methods

The study population consisted of 36 male patients with (n = 28, stage 1–4) and at risk for (n = 8) COPD aged over 50 years. TEE was measured by the doubly labeled water method, and PAL was calculated as the TEE/basal metabolic rate estimated by the indirect method. The cross-sectional areas and densities of the pectoralis muscles, rectus abdominis muscles, and erector spinae muscles were measured. We evaluated the relationship between these muscle measurements and clinical outcomes, including body composition, lung function, muscle strength, TEE, and PAL.

Results

All the muscle areas were significantly associated with TEE, severity of emphysema, and body composition indices such as body mass index, fat-free mass, and trunk muscle mass. All trunk muscle densities were correlated with PAL. The product of the rectus abdominis muscle area and density showed the highest association with TEE (r = 0.732) and PAL (r = 0.578). Several trunk muscle measurements showed significant correlations with maximal inspiratory and expiratory pressures, indicating their roles in respiration.

Conclusions

CT-derived measurements for trunk muscles are helpful in evaluating physical status and function in patients with or at risk for COPD. Particularly, trunk muscle evaluation may be a useful marker reflecting TEE and PAL.

Sarcopenia in COPD: a systematic review and meta-analysis

COPD is associated with a progressive loss of muscle mass and function. However, there is an unmet need to define and standardise methods to estimate the prevalence of sarcopenia in COPD patients.

We performed a systematic review and meta-analysis of the prevalence of this extrapulmonary manifestation in COPD patients. We searched Embase, Medline (Ovid), CINAHL (EBSCO), Web of Science, Scopus and Google Scholar for studies published up to January 17, 2019, assessing sarcopenia in COPD patients based on low muscle mass and decreased muscle function. Interventional studies, in vitro experiments, protocols or reviews and meta-analyses were excluded. We estimated heterogeneity (I²) and assessed significance (Q) using a Chi-squared test for estimates obtained from random-effects models.

4465 articles were initially identified. After removing the duplicates and applying the selection criteria, we reviewed 62 full-text articles. Finally, 10 articles (n=2565 COPD patients) were included in this systematic review and meta-analyses. Overall, the prevalence of sarcopenia in patients with COPD was 21.6% (95% CI 14.6–30.9%, I²=94%), ranging from 8% in population-based to 21% in clinic-based studies, and 63% in COPD patients residing in nursing homes.

Sarcopenia is frequently observed in COPD patients, with varying prevalence across population settings. Sarcopenia in COPD should be assessed using standardised tests and cut-off points from sarcopenia consensus criteria for clinical practice and international comparisons.

We confirmed a high prevalence of sarcopenia in COPD patients, with varying prevalence across population settings. We recommend adhering to the sarcopenia consensus criteria to systematically evaluate the muscle health of COPD patients.http://bit.ly/2KA6weh

Computed tomography-derived area and density of pectoralis muscle associated disease severity and longitudinal changes in chronic obstructive pulmonary disease: a case control study

BACKGROUND

Muscle wasting is associated with prognosis in patients with chronic obstructive pulmonary disease (COPD). The cross-sectional area of skeletal muscles on computed tomography (CT) could serve as a method to evaluate body composition. The present study aimed to determine the ability of CT-derived pectoralis muscle area (PMA) and pectoralis muscle density (PMD) to determine the severity of COPD and change in longitudinal pulmonary function in patients with COPD.

METHODS

A total of 293 participants were enrolled in this study, a whom 222 had undergone at least two spirometry measurements within 3 years after baseline data acquisition. PMA and PMD were measured from a single axial slice of chest CT above the aortic arch at baseline. The emphysema index and bronchial wall thickness were quantitatively assessed in all scans. The generalized linear model was used to determine the correlation between PMA and PMD measurements and pulmonary function.

RESULTS

PMA and PMD were significantly associated with baseline lung function and the severity of emphysema (P < 0.05). Patients with the lowest PMA and PMD exhibited significantly more severe airflow obstruction (β = - 0.06; 95% confidence interval: - 0.09 to - 0.03]. PMA was statistically associated with COPD assessment test (CAT) score (P = 0.033). However, PMD did not exhibit statistically significant correlation with either CAT scores or modified Medical Research Council scores (P > 0.05). Furthermore, neither PMA nor PMD were associated with changes in forced expiratory volume in 1 s over a 3-year periods.

CONCLUSIONS

CT-derived features of the pectoralis muscle may be helpful in predicting disease severity in patients with COPD, but are not necessarily associated with longitudinal changes in lung function.

Factors associated with appendicular skeletal muscle mass among male Chinese patients with stable chronic obstructive pulmonary disease: A hospital-based cross-sectional study

Limbs muscle wasting is a common disorder in patients with chronic obstructive pulmonary disease (COPD) that limits daily activities and exercise intolerance, especially in males. The present study aimed to estimate the prevalence of appendicular skeletal muscle mass (ASM) in male patients with stable COPD. In addition, factors associated with parameters of ASM were also investigated.We recruited 116 male patients with stable COPD from the outpatient clinic between September 2016 and December 2017. For each patient, we obtained demographic characteristics and measured post-bronchodilator forced expiratory volume in 1 second, symptoms, exacerbations history, and ASM. ASM was defined as the sum of the muscle masses of the 4 limbs.Appendicular skeletal muscle mass index (ASMI) in male patients with stable COPD was 8.2 ± 0.9 kg/m, and the prevalence of low skeletal muscle mass was 7.8% (9 of 116 patients). Multiple linear-regression analysis showed that body mass index, occupation, fat-free mass index, and the modified medical research council scale were significantly correlated with ASMI. Compared with nonexercise group, lower limb muscle mass and ASM were significantly improved in physical exercise group.Underweight, retirement, fat-free mass depletion, and severe dyspnea are all risk factors for ASM in male patients with stable COPD. Our findings also justify the importance of exercise training in improving ASM.

Inspiratory muscle strength, diaphragmatic mobility, and body composition in chronic obstructive pulmonary disease

BACKGROUND AND PURPOSE

Chronic obstructive pulmonary disease (COPD) is a systemic inflammatory disease that can cause repercussions on respiratory muscles and body composition. The aim of the current study was to evaluate inspiratory muscle strength, diaphragmatic mobility, and body composition in COPD subjects and to correlate these variables.

METHODS

This was a cross-sectional study performed with 21 COPD patients. Inspiratory muscle strength (manovacuometry), pulmonary function test (forced vital capacity [FVC], forced expiratory volume in 1 s [FEV₁ ], and FEV₁ /FVC ratio), diaphragmatic mobility (ultrasonography), and body composition (bioelectrical impedance analysis) were examined.

RESULTS

COPD individuals in Stages II (28.9%), III (52%), and IV (19%) according to Global Initiative for Chronic Obstructive Disease were recruited, 61.9% of which were men. Inspiratory muscle weakness was found in 47.6% of subjects, who presented a lower fat-free mass percentage (p = 0.017) and smaller fat-free mass index (p = 0.001) and greater fat mass percentage (p = 0.029) and less diaphragmatic mobility (p = 0.007) compared with the nonrespiratory weakness group. Maximal inspiratory pressure exhibited a moderately positive relationship to the fat-free mass index (r = 0.767, p < 0.001) and a weak positive relationship to diaphragmatic mobility (r = 0.496, p = 0.022).

CONCLUSION

Our study showed a high prevalence of inspiratory muscle weakness based on the severity of airway obstruction and on the presence of muscular depletion. The evaluation of body composition detected important changes. It also demonstrated that not only muscular weakness was present in these patients but also this had repercussions on the mobility of the diaphragm muscle.

Body composition and sarcopenia in patients with chronic obstructive pulmonary disease

PURPOSE

Changes in body composition are commonly present in chronic obstructive pulmonary disease (COPD). The main aim of this study were to evaluate changes in body composition and the prevalence of pre-sarcopenia and sarcopenia in patients with COPD, compared with two control groups and correlate these parameters with indices of COPD severity (VEF1 and GOLD) and prognosis (BODE).

METHODS

This was a cross-sectional study in COPD patients (DG) that undergone body composition assessment by DXA. Two control groups were used, smokers individuals without COPD (smokers group, SG), and healthy never smokers individuals (never smokers group, NSG).

RESULTS

DG comprised 121 patients (65 women, mean age 67.9 ± 8.6 years). The percentage of total body fat mass (TFM) was significantly lower in DG in both genders, despite no difference in BMI. Both BMI and relative skeletal muscle mass index (RSMI) decreased according to the worsening of GOLD in men and women, as well as the TFM and total lean mass (TLM) in men. As BODE get worse, BMI and RSMI decreased in both sexes, as well as TLM in men. The prevalence of pre-sarcopenia in the DG was 46.3% and no different with controls. In DG 12.4% were sarcopenic. Patients with sarcopenia were older and had worse prognosis. Higher BODE prognostic index, higher the prevalence of sarcopenia (OR 3.5, 95% CI 1.06-11.56, p = 0.035).

CONCLUSIONS

This study showed alterations in body composition parameters in patients with COPD. A high prevalence of sarcopenia and the association with worse prognostic index.