Sarcopenia in Advanced COPD Affects Cardiometabolic Risk Reduction by Short-Term High-intensity Pulmonary Rehabilitation

Associations of nutritional intake and inflammatory factors with sarcopenia in community-dwelling older adults: a cross-sectional study

PURPOSE

Sarcopenia is an age-related disease that is related to nutritional intake and chronic low-grade inflammation. The aim of this study was to investigate the association of dietary intake, inflammatory markers and sarcopenia among the community-dwelling older adults.

METHODS

A total of 1001 older adults aged 60 and above were recruited. According to the criteria established by the Asian Working Group for Sarcopenia 2019, this paper assessed the presence of sarcopenia and using a Food Frequency Questionnaire to evaluate daily dietary intake. Serum levels of inflammatory markers were measured using the ELISA method.

RESULTS

A total of 1001 participants took part in the study (mean 70.6 years), comprising 396 males and 605 females, the prevalence of sarcopenia was 19.6%. Multivariate analysis revealed that high levels of leucine, methionine, threonine, histidine, aspartic acid, calcium, zinc, and vitamin C were associated with a lower risk of sarcopenia. Higher dietary inflammatory index scores were associated with a higher risk of sarcopenia (OR  1.67, 95% CI 1.12-2.47). Higher tumor necrosis factor-like weak inducer of apoptosis (TWEAK) (OR 1.04, 95% CI 1.02-1.07) was associated with a higher risk of sarcopenia, and a lower skeletal muscle mass, strength, and physical function. Conversely, higher insulin-like growth factor-1 (IGF-1) (OR 0.83, 95% CI 0.74-0.94) and glutathione S-transferase (GST) (OR 0.75, 95% CI 0.61-0.91) were associated with a lower risk of sarcopenia.

CONCLUSIONS

This cross-sectional study revealed alterations in amino acid and micronutrient intake among older adults with sarcopenia. The levels of TWEAK were associated with an increased risk of sarcopenia, whereas IGF-1 and GST were associated with a reduced risk of sarcopenia.

Current perspectives on the rehabilitation of COPD patients with comorbidities

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is frequently accompanied by a variety of comorbidities, complicating management and rehabilitation efforts. Understanding this interplay is crucial for optimizing patient outcomes.

AREAS COVERED

This review, based on the MEDLINE, Embase and Cochrane Library databases, summarizes the main research on the rehabilitation of patients with COPD, with an emphasis on relevant comorbidities, such as cardiovascular diseases, pulmonary hypertension, lung cancer, metabolic, musculoskeletal, and gastrointestinal disorders. anxiety/depression and cognitive disorders. The study highlights the importance of pre-participation assessments, ongoing monitoring and personalized rehabilitation programs. A review includes a comprehensive literature search to assess the scientific evidence on these interventions and their impact.

EXPERT OPINION

The integration of cardiorespiratory rehabilitation program is essential for improving physical capacity and quality of life in COPD patients with comorbidities. While existing studies highlight positive outcomes, challenges such as interdisciplinary collaboration and access to rehabilitation services remain. Future strategies must prioritize personalized and integrated approaches programs combining pharmacological optimization and a close monitoring during cardiopulmonary rehabilitation to significantly reduce hospital readmissions and mortality, even in patients with complex multimorbidities. Continued research is necessary to refine rehabilitation protocols and better understand the complexities of managing COPD alongside cardiac conditions.

Exploring the relationship between sarcopenia and 11 respiratory diseases: a comprehensive mendelian randomization analysis

BACKGROUND

Sarcopenia (SP) is an aging-related loss of muscle mass and function, affecting the respiratory system. However, the causality of the association between sarcopenia on lung diseases remains elusive.

METHODS

The bidirectional univariate Mendelian randomization (UVMR), multivariate MR (MVMR) analysis, and mediation MR were utilized to systematically investigate the genetic causal relationship of SP and 11 respiratory diseases. Independent genomic variants related to sarcopenia or respiratory diseases were identified as instrumental variables (IVs), and the summary level data of genome-wide associated studies (GWAS) were obtained from the UK biobank and FinnGen. MVMR analysis was conducted to explore the mediation effects of body mass index (BMI), Alcohol Use Disorders Identification Test (AUDIT), smoking, education attainment (EA), physical activity, and Type 2 Diabetes Mellitus (T2DM).

RESULTS

Forward UVMR analysis based on the primary method revealed that pneumoconiosis was associated with a higher risk of appendicular lean mass (ALM) (OR = 1.01, p = 0.03), and BMI (10.65%), smoking (10.65%), and physical activity (17.70%) had a mediating role in the effect of pneumoconiosis on ALM. In reverse MR analysis, we found that genetically predicted ALM was significantly associated with an increased risk of pulmonary embolism (PE) (OR = 1.24, p = 7.21E-05). Chronic obstructive pulmonary disease (COPD) (OR = 0.98, p = 0.002) and sarcoidosis (OR = 1.01, p = 0.004) were identified to increase the loss of left-hand grip strength (HGS). Conversely, the increase in left- HGS presented a protective effect on chronic bronchitis (CB) (OR = 0.35, p = 0.03), (OR = 0.80, p = 0.02), and asthma (OR = 0.78, p = 0.04). Similarly, the loss of the right-HGS elevated the risk of low respiratory tract infection (LRTI) (OR = 0.97, p = 0.02) and bronchiectasis (OR = 1.01, p = 0.03), which is also an independent protective factor for LRTI and asthma. In the aspects of low HGS, the risk of LRTI was increased after MVMR analysis, and the risk of sarcoidosis and pneumoconiosis was elevated in the reverse analysis. Lastly, asthma was found to be related to the loss of the usual walking pace, and the reverse MR analysis suggested a causal relationship between the usual walking pace and LRTI (OR = 0.32, p = 2.79 × 10-5), asthma (OR = 0.24, p = 2.09 × 10-6), COPD (OR = 0.22, p = 6.64 × 10-4), and PE(OR = 0.35, p = 0.03).

CONCLUSIONS

This data-driven MR analysis revealed SP was bidirectional causally associated with lung diseases, providing genetic evidence for further mechanistic and clinical studies to understand the crosstalk between SP and lung diseases.

Predictive and therapeutic value of lipoprotein-associated phospholipaseA2 in sarcopenia in chronic obstructive pulmonary disease

BACKGROUND

Sarcopenia, characterized by progressive muscle dysfunction, is a common complication of chronic obstructive pulmonary disease (COPD). Our previous study revealed serum Lipoprotein-associated phospholipaseA2 (Lp-PLA2) level significantly increased in COPD and associated with exercise tolerance. This study further investigated the functions and target potential of Lp-PLA2 for sarcopenia in COPD.

METHODS

The circulating Lp-PLA2 level/enzyme activity in COPD patients and age-matched healthy volunteers were measured. Clinical parameters on skeletal muscle were measured and their correlations with Lp-PLA2 were analyzed. We explored the involvement of Lp-PLA2 in vivo and treatment effectiveness of darapladib (a specific Lp-PLA2 inhibitor) in CS-induced muscle dysfunction models.

RESULTS

Circulating Lp-PLA2 level/enzyme activity was elevated in COPD patients compared with healthy controls, negatively associated with skeletal muscle mass and function. In CS-induced muscle dysfunction murine models, up-regulated serum Lp-PLA2 level/enzyme activity was verified again. In CS-exposed mouse models, darapladib treatment reversed muscle mass loss and muscle dysfunction, meanwhile rescued upregulation of MuRF1 and atrogin-1, and activation of inflammatory factors, oxidant enzymes and NF-κB signaling.

CONCLUSIONS

Lp-PLA2 could be a potential indicator for sarcopenia in COPD. Darapladib, a Lp-PLA2 inhibitor, can alleviate CS-induced skeletal muscle dysfunction and represents a potential therapeutic for sarcopenia in COPD.

Role of nutrition in patients with coexisting chronic obstructive pulmonary disease and sarcopenia

Chronic obstructive pulmonary disease (COPD) is one of the most common chronic diseases in the elderly population and is characterized by persistent respiratory symptoms and airflow obstruction. During COPD progression, a variety of pulmonary and extrapulmonary complications develop, with sarcopenia being one of the most common extrapulmonary complications. Factors that contribute to the pathogenesis of coexisting COPD and sarcopenia include systemic inflammation, hypoxia, hypercapnia, oxidative stress, protein metabolic imbalance, and myocyte mitochondrial dysfunction. These factors, individually or in concert, affect muscle function, resulting in decreased muscle mass and strength. The occurrence of sarcopenia severely affects the quality of life of patients with COPD, resulting in increased readmission rates, longer hospital admission, and higher mortality. In recent years, studies have found that oral supplementation with protein, micronutrients, fat, or a combination of nutritional supplements can improve the muscle strength and physical performance of these patients; some studies have also elucidated the possible underlying mechanisms. This review aimed to elucidate the role of nutrition among patients with coexisting COPD and sarcopenia.

Relationship between asthma and sarcopenia in the elderly: a nationwide study from the KNHANES

OBJECTIVE

Few studies have investigated the relationship between asthma and sarcopenia. We aimed to examine the relationship between asthma and sarcopenia in a community-dwelling geriatric population, especially regarding lung function and asthma control.

METHODS

A cross-sectional dataset from the Korean National Health and Nutrition Examination Survey 2008-2011 was utilized. Data regarding asthma history, age at asthma onset, recent asthma exacerbations, and hospitalization for asthma exacerbations were obtained using structured questionnaires. Appendicular skeletal muscle was calculated as the sum of the skeletal muscle mass, and physical activity was assessed using the International Physical Activity Questionnaire.

RESULTS

Asthma presented an estimated incidence of 6.17 ± 0.37% in the elderly. Groups were divided and analyzed according to asthma, muscle mass, and physical activity. Sarcopenia was associated with aging, male sex, smoking history, low body mass index (BMI), and reduced lung function with or without asthma. Sarcopenic asthma had a younger onset and reduced physical activity than non-sarcopenic asthma. Obstructive patterns were more frequent in asthmatics exhibiting low or moderate physical activity levels than in those with high activity, but asthma control was not associated with sarcopenia and physical activity. Multivariate logistic regression analyses showed that compared with control, sarcopenic asthma was associated with FEV1 < 60%, and airway obstruction, and with aging, male, and lower BMI, compared with non-sarcopenic asthma.

CONCLUSIONS

Our findings suggest that decreased muscle mass and physical activity levels contribute to reduced lung function in elderly asthmatics. Furthermore, sarcopenic asthma was associated with aging, low BMI, and reduced lung function in the elderly.

Prevalence of sarcopenia in patients with COPD through different musculature measurements: An updated meta-analysis and meta-regression

Aim

Chronic obstructive pulmonary disease (COPD) patients vary widely in terms of the prevalence of sarcopenia, which is partially attributed to differences in diagnostic criteria and disease severity. There are several different musculature measurements that are used to quantify sarcopenia. This study included published literature for meta-analysis to assess the sarcopenia prevalence in COPD patients and correlate the disease with the clinical characteristics of such patients.

Methods

A comprehensive review of the English and Chinese literature on sarcopenia prevalence in COPD patients was conducted using electronic databases such as China National Knowledge Infrastructure (CNKI), Web of Science, Cochrane Library, EMBASE, PubMed, and Wanfang. Two researchers analyzed the studies for Newcastle-Ottawa Scale. The software Stata 11.0 was employed for the analysis of the acquired data. The standard mean differences method was utilized for the estimation and quantification of the effect size. Furthermore, a fixed- or random-effects model was employed for conducting a combined analysis.

Results

In total, 56 studies were included as per the specific inclusion criteria. The resulting data of the assessed COPD patients in this research indicated a 27% prevalence of sarcopenia. Further analysis of subgroups was executed per disease severity, ethnicity, diagnostic criteria, gender, and age. Per these findings, increased disease severity elevated the prevalence of sarcopenia. The Latin American and Caucasian populations indicated an increased prevalence of sarcopenia. In addition, the prevalence of sarcopenia was related to diagnostic criteria and definition. Male COPD patients had a higher prevalence of sarcopenia than female COPD patients. COPD patients with an average age greater than 65 had a slightly higher prevalence of sarcopenia. COPD patients with comorbid sarcopenia had poorer pulmonary function, activity tolerance, and clinical symptoms than patients with COPD alone.

Conclusion

Sarcopenia prevalence is high (27%) in COPD patients. In addition, these patients had worse pulmonary function and activity tolerance compared to patients without sarcopenia.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=367422, identifier CRD42022367422.

Ultrasound Assessment of the Rectus Femoris in Patients with Chronic Obstructive Pulmonary Disease Predicts Sarcopenia

PURPOSE

Sarcopenia, an age-related loss of skeletal muscle mass and function, is frequent in patients with chronic obstructive pulmonary disease (COPD) and is linked to a poor prognosis. The diagnosis of sarcopenia requires specific equipment and is inconvenient to introduce into clinical practice. Ultrasound is an innovative method to assess muscle quantity. The objective of this research was to evaluate the use of ultrasound for prospectively screening for sarcopenia in COPD patients.

PATIENTS AND METHODS

A total of 235 stable patients with COPD were included in this observational study and divided into development and validation sets. The Asian Working Group for Sarcopenia standards were used to define sarcopenia. The thickness (RF_thick) and cross-sectional area (RF_csa) of the rectus femoris were measured using ultrasound. Receiver operating characteristic curve analysis of RF_thick and RF_csa was used to predict sarcopenia. Nomogram models were constructed based on RF_thick, RF_csa, age and body mass index to identify sarcopenia.

RESULTS

Sarcopenia was present in 83 (35.32%) patients. Patients with sarcopenia had advanced age, decreased pulmonary function, decreased physical function and poor clinical outcomes. RF_thick and RF_csa showed good predictive ability for sarcopenia in the development and validation sets. The nomogram based on RF_thick and RF_csa could detect sarcopenia in COPD patients, and all had significant predictive performance in the development and validation sets. The calibration plot showed good agreement between the nomogram predictions and actual observations.

CONCLUSION

The ultrasound measurement of the rectus femoris has potential for the clinical assessment of sarcopenia in patients with COPD.

Myostatin/HIF2α-Mediated Ferroptosis is Involved in Skeletal Muscle Dysfunction in Chronic Obstructive Pulmonary Disease

Objective

Methods

Results

Conclusion

β-Sitosterol Attenuates Dexamethasone-Induced Muscle Atrophy via Regulating FoxO1-Dependent Signaling in C2C12 Cell and Mice Model

Sarcopenia refers to a decline in muscle mass and strength with age, causing significant impairment in the ability to carry out normal daily functions and increased risk of falls and fractures, eventually leading to loss of independence. Maintaining protein homeostasis is an important factor in preventing muscle loss, and the decrease in muscle mass is caused by an imbalance between anabolism and catabolism of muscle proteins. Although β-sitosterol has various effects such as anti-inflammatory, protective effect against nonalcoholic fatty liver disease (NAFLD), antioxidant, and antidiabetic activity, the mechanism of β-sitosterol effect on the catabolic pathway was not well known. β-sitosterol was assessed in vitro and in vivo using a dexamethasone-induced muscle atrophy mice model and C2C12 myoblasts. β-sitosterol protected mice from dexamethasone-induced muscle mass loss. The thickness of gastrocnemius muscle myofibers was increased in dexamethasone with the β-sitosterol treatment group (DS). Grip strength and creatine kinase (CK) activity were also recovered when β-sitosterol was treated. The muscle loss inhibitory efficacy of β-sitosterol in dexamethasone-induced muscle atrophy in C2C12 myotube was also verified in C2C12 myoblast. β-sitosterol also recovered the width of myotubes. The protein expression of muscle atrophy F-box (MAFbx) was increased in dexamethasone-treated animal models and C2C12 myoblast, but it was reduced when β-sitosterol was treated. MuRF1 also showed similar results to MAFbx in the mRNA level of C2C12 myotubes. In addition, in the gastrocnemius and tibialis anterior muscles of mouse models, Forkhead Box O1 (FoxO1) protein was increased in the dexamethasone-treated group (Dexa) compared with the control group and reduced in the DS group. Therefore, β-sitosterol would be a potential treatment agent for aging sarcopenia.

Sarcopenia is associated with cardiovascular risk in men with COPD, independent of adiposity

Background

Sarcopenia is a well-established risk factor for atherosclerotic cardiovascular disease (ASCVD), but its relationship with chronic obstructive pulmonary disease (COPD) has not been fully determined. This study is aimed to investigate the association between sarcopenia and risk for ASCVD in patients with COPD, independent of central obesity and fat mass.

Methods

Data regarding 704 men with COPD (mean age: 63.4 years) were extracted from the 2008 to 2011 Korean National Health and Nutrition Examination Surveys. Sarcopenia index and fat mass were assessed using dual-energy X-ray absorptiometry. Sarcopenia was defined according to the presence of sarcopenia index values < 1 standard deviation from the cutoff (0.774) among the study participants. ASCVD risk was evaluated using American College of Cardiology/American Heart Association guidelines. High probability of ASCVD was defined as ASCVD risk > 20%.

Results

The quartile-stratified sarcopenia index was negatively associated with ASCVD risk (P < 0.001). ASCVD risk and prevalence of high ASCVD risk were significantly greater in sarcopenic participants than in non-sarcopenic participants, regardless of central obesity and fat mass (all P < 0.001). Multivariate regression analyses demonstrated an independent association between sarcopenia and ASCVD risk (estimated ± standard error = 3.63 ± 0.77%, P < 0.001) and high ASCVD risk (odds ratio [OR] = 2.32, 95% confidence interval [CI] 1.05–5.15, P = 0.039). Furthermore, sarcopenia was an independent factor for high ASCVD risk in participants with moderate to very severe airflow limitation (OR = 2.97, 95% CI 1.06–8.36, P < 0.001).

Conclusions

Sarcopenia was significantly associated with an increased risk for ASCVD in men with COPD, independent of central obesity and fat mass. High ASCVD risk was significantly associated with sarcopenia, particularly in participants with moderate to very severe airflow limitation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02109-3.

Resistin as a Systemic Inflammation-Related Biomarker for Sarcopenia in Patients With Chronic Obstructive Pulmonary Disease

Background

Sarcopenia is common in patients with chronic obstructive pulmonary disease (COPD) and is mainly caused by systemic inflammation. Resistin acts as a proinflammatory cytokine and is involved in the activation of multiple inflammatory signaling pathways. The aim of this study was to determine the relationship between resistin levels and systemic inflammation and to assess the clinical value of circulating resistin for sarcopenia in patients with COPD.

Methods

In this prospective observational study, we enrolled 235 patients with COPD who were divided into development and validation sets. The definition of sarcopenia followed the guidelines from the Asian Working Group for Sarcopenia. Serum concentrations of resistin and TNF-α were measured using an enzyme-linked immunosorbent assay (ELISA).

Results

In this study, higher serum resistin levels were significantly associated with lower skeletal muscle mass and muscular strength. The serum resistin levels in patients with sarcopenia were significantly higher than those in patients without sarcopenia. The serum resistin level had positive correlations with the serum TNF-α level (r = 0.250, p = 0.007). The predictive efficacy of the serum resistin level (AUC: 0.828) for sarcopenia was superior to that of the serum TNF-α level (AUC: 0.621). The cutoff point (7.138 ng/ml) for the serum resistin level was validated in the validation set (AUC: 0.818).

Conclusions

Serum resistin levels were associated with systemic inflammation and can be used accurately and easily to predict sarcopenia in patients with COPD.

Growth Differentiation Factor-15 as a Biomarker for Sarcopenia in Patients With Chronic Obstructive Pulmonary Disease

Purpose

Sarcopenia is an important factor contributing to comorbidities in patients with chronic obstructive pulmonary disease (COPD) and is an independent risk factor for increased mortality. The diagnostic process for sarcopenia requires specific equipment and specialized training and is difficult procedurally. A previous study found that GDF15 levels are associated with skeletal muscle mass and function in patients with COPD. However, whether circulating GDF15 levels can be used for the prediction of sarcopenia in patients with COPD is unknown.

Methods

This study included 235 patients with stable COPD who were divided into a development set (n = 117) and a validation set (n = 118), and we followed the definition of sarcopenia as defined by the guidelines from the Asian Working Group for Sarcopenia. Serum concentrations of GDF15 were measured using an enzyme-linked immunosorbent assay (ELISA), and construction of a nomogram and decision curve analysis were performed using the R package “rms.”

Results

In this study, serum GDF15 levels were negatively associated with skeletal muscle mass (r = –0.204, p = 0.031), handgrip strength (r = –0.274, p = 0.004), quadriceps strength (r = –0.269, p = 0.029), and the thickness (r = –0.338, p < 0.001) and area (r = –0.335, p < 0.001) of the rectus femoris muscle in patients with COPD. Furthermore, the serum levels of GDF15 in patients with sarcopenia were significantly higher than those in controls. Importantly, serum levels of GDF15 could effectively predict sarcopenia in patients with COPD based on the development set (AUC = 0.827) and validation set (AUC = 0.801). Finally, a nomogram model based on serum GDF15 levels and clinical features showed good predictive ability (AUC > 0.89) in the development and validation sets.

Conclusion

Serum GDF15 levels could be used to accurately and easily evaluate sarcopenia in patients with COPD.

The Association between Fat-Free Mass and Exercise Test Outcomes in People with Chronic Obstructive Pulmonary Disease: A Systematic Review

People with chronic obstructive pulmonary disease (COPD) tend to have abnormally low levels of fat-free mass (FFM), which includes skeletal muscle mass as a central component. The purpose of this systematic review was to synthesise available evidence on the association between FFM and exercise test outcomes in COPD. MEDLINE, Cochrane Library, EMBASE, Web of Science, and Scopus were searched. Studies that evaluated exercise-related outcomes in relation to measures of FFM in COPD were included. Eighty-three studies, containing 18,770 (39% female) COPD participants, were included. Considerable heterogeneity was identified in the ways that FFM and exercise test outcomes were assessed; however, higher levels of FFM were generally associated with greater peak exercise capacity. This association was stronger for some exercise test outcomes (e.g. peak rate of oxygen consumption during incremental cycle exercise testing) than others (e.g. six-minute walking distance). This review identified heterogeneity in the methods used for measuring FFM and exercise capacity. There was, in general, a positive association between FFM and exercise capacity in COPD. There was also an identified lack of studies investigating associations between FFM and temporal physiological and perceptual responses to exercise. This review highlights the significance of FFM as a determinant of exercise capacity in COPD.

Effect of Exercise on Secondary Sarcopenia: A Comprehensive Literature Review

Simple Summary

Sarcopenia is an inevitable component of aging. It is officially recognized as a muscle disease with an ICD-10-MC diagnosis code that can be used to bill for care in some countries. Sarcopenia can be classified into primary or age-related sarcopenia and secondary sarcopenia. The condition is referred to as secondary sarcopenia when any other comorbidities are present in conjunction with aging. Secondary sarcopenia is more prevalent than primary sarcopenia and requires special attention. Exercise interventions may help in our understanding and prevention of sarcopenia with a specific morbidity Glomerular filtration rate that exercise improves muscle mass, quality or physical function in elderly subjects with cancer, type 2 diabetes, kidney diseases and lung diseases. In this review, we summarize recent research that has studied the impact of exercise on patients with secondary sarcopenia, specifically those with one comorbid condition. We did not discover any exercise intervention specifically for subjects with secondary sarcopenia (with one comorbidity). Even though there is a strong argument for using exercise to improve muscle mass, quality or physical function in subjects with cancer, type 2 diabetes, kidney diseases, lung diseases and many more, very few studies have reported baseline sarcopenia assessments. Based on the trials summarized in this review, we may propose but not conclude that resistance, aerobic, balance training or even walking can be useful in subjects with secondary sarcopenia with only one comorbidity due to the limited number of trials. This review is significant because it reveals the need for broad-ranging research initiatives involving secondary sarcopenic patients and highlights a large secondary sarcopenia research gap.

Abstract

Background: Sarcopenia has been recognized as an inevitable part of aging. However, its severity and the age at which it begins cannot be predicted by age alone. The condition can be categorized into primary or age-related sarcopenia and secondary sarcopenia. Sarcopenia is diagnosed as primary when there are no other specific causes. However, secondary sarcopenia occurs if other factors, including malignancy or organ failure, are evident in addition to aging. The prevalence of secondary sarcopenia is far greater than that of primary sarcopenia and requires special attention. To date, nutrition and exercise have proven to be the best methods to combat this disease. The impact of exercise on subjects suffering from sarcopenia with a specific morbidity is worthy of examination for understanding and prevention. The purpose of this review, therefore, is to summarize recent research that has investigated the impact of exercise in patients with secondary sarcopenia, specifically with one comorbidity. Methods: Pubmed, Web of Science, Embase and Medline databases were searched comprehensively with no date limit for randomized controlled trials. The literature was specifically searched for clinical trials in which subjects were sarcopenic with only one comorbidity participating in an exercise intervention. The most visible comorbidities identified and used in the search were lung disease, kidney disease, heart disease, type 2 diabetes, cancer, neurological diseases, osteoporosis and arthritis. Results: A total of 1752 studies were identified that matched the keywords. After removing duplicates, there were 1317 articles remaining. We extracted 98 articles for full screening. Finally, we included 21 relevant papers that were used in this review. Conclusion: Despite a strong rationale for using exercise to improve muscle mass, quality or physical function in subjects with cancer, type 2 diabetes, kidney disease, lung disease and many more, baseline sarcopenia evaluation has been reported in very few trials. The limited number of studies does not allow us to conclude that exercise can improve sarcopenia in patients with other comorbidities. This review highlights the necessity for wide-ranging research initiatives involving secondary sarcopenic patients.

Diagnosis, prevalence, and clinical impact of sarcopenia in COPD: a systematic review and meta-analysis

Sarcopenia prevalence and its clinical impact are reportedly variable in chronic obstructive pulmonary disease (COPD) due partly to definition criteria. This review aimed to identify the criteria used to diagnose sarcopenia and the prevalence and impact of sarcopenia on health outcomes in people with COPD. This review was registered in PROSPERO (CRD42018092576). Five electronic databases were searched to August 2018 to identify studies related to sarcopenia and COPD. Study quality was assessed using validated instruments matched to study designs. Sarcopenia prevalence was determined using authors' definitions. Comparisons were made between people who did and did not have sarcopenia for pulmonary function, exercise capacity, quality of life, muscle strength, gait speed, physical activity levels, inflammation/oxidative stress, and mortality. Twenty-three studies (70% cross-sectional) from Europe (10), Asia (9), and North and South America (4) involving 9637 participants aged ≥40 years were included (69.5% men). Sarcopenia criteria were typically concordant with recommendations of hEuropean and Asian consensus bodies. Overall sarcopenia prevalence varied from 15.5% [95% confidence interval (CI) 11.8-19.1; combined muscle mass, strength, and/or physical performance criteria] to 34% (95%CI 20.6-47.3; muscle mass criteria alone) (P = 0.009 between subgroups) and was greater in people with more severe [37.6% (95%CI 24.8-50.4)] versus less severe [19.1% (95%CI 10.2-28.0)] lung disease (P = 0.020), but similar between men [41.0% (95%CI 26.2-55.9%)] and women [31.9% (95%CI 7.0-56.8%)] (P = 0.538). People with sarcopenia had lower predicted forced expiratory volume in the first second (mean difference -7.1%; 95%CI -9.0 to -5.1%) and poorer exercise tolerance (standardized mean difference -0.8; 95%CI -1.4 to -0.2) and quality of life (standardized mean difference 0.26; 95%CI 0.2-0.4) compared with those who did not (P < 0.001 for all). No clear relationship was observed between sarcopenia and inflammatory or oxidative stress biomarkers. Incident mortality was unreported in the literature. Sarcopenia is prevalent in a significant proportion of people with COPD and negatively impacts upon important clinical outcomes. Opportunities exist to optimize its early detection and management and to evaluate its impact on mortality in this patient group.

Pulmonary function and functional capacity cut-off point to establish sarcopenia and dynapenia in patients with COPD

Objective

To establish a cut-off point for clinical and functional variables to determinate sarcopenia and dynapenia in COPD patients, and to analyze the impact of skeletal muscle dysfunction (SMD) on these variables.

Methods

Cross-sectional study, screened COPD patients for sarcopenia or dynapenia through low muscle mass and hand grip strength (HGS). Clinical variables: pulmonary function, respiratory muscle strength and functional capacity (FC). The precision of the variables in determining points of predictive cut-off for sarcopenia or dynapenia were performed using the Receiver Operating Characteristic curve and two-way analysis of variance.

Results

20 COPD patients stratified for sarcopenia (n = 11) and dynapenia (n = 07). Sarcopenia group presented lower lean mass and lower maximal inspiratory pressure (MIP), decreased HGS, reduced FC (p<0.050). Dynapenia group presented reduced MIP, lower HGS and walked a shorter distance at Incremental shuttle walk test (ISWT) (p<0.050). We found cut-off points of forced expiratory volume in one second (FEV1), MIP and maximal expiratory pressure (MEP) and ISWT. It is possible to identify sarcopenia or dynapenia in these patients. We found the coexistence of the conditions (SMD effect) in COPD – reduction in the distance in the ISWT (p = 0.002) and %ISWT (p = 0.017).

Conclusion

In moderate to very severe COPD patients the sarcopenia could be predicted by FEV₁ (%predicted) < 52, MIP < 73 cmH2O, MEP < 126 cmH2O and distance traveled of < 295 m in ISWT. Whereas dynapenia could be predicted by FEV₁ < 40%, MIP < 71 cmH2O, MEP < 110 cmH2O and distance of < 230 m traveled in ISWT.

Distinct skeletal muscle molecular responses to pulmonary rehabilitation in chronic obstructive pulmonary disease: a cluster analysis

BACKGROUND

Pulmonary rehabilitation (PR) is a cornerstone in the management of chronic obstructive pulmonary disease (COPD), targeting skeletal muscle to improve functional performance. However, there is substantial inter-individual variability in the effect of PR on functional performance, which cannot be fully accounted for by generic phenotypic factors. We performed an unbiased integrative analysis of the skeletal muscle molecular responses to PR in COPD patients and comprehensively characterized their baseline pulmonary and physical function, body composition, blood profile, comorbidities, and medication use.

METHODS

Musculus vastus lateralis biopsies were obtained from 51 COPD patients (age 64 ± 1 years, sex 73% men, FEV₁ , 34 (26-41) %pred.) before and after 4 weeks high-intensity supervised in-patient PR. Muscle molecular markers were grouped by network-constrained clustering, and their relative changes in expression values-assessed by qPCR and western blot-were reduced to process scores by principal component analysis. Patients were subsequently clustered based on these process scores. Pre-PR and post-PR functional performance was assessed by incremental cycle ergometry and 6 min walking test (6MWT).

RESULTS

Eight molecular processes were discerned by network-constrained hierarchical clustering of the skeletal muscle molecular rehabilitation responses. Based on the resulting process scores, four clusters of patients were identified by hierarchical cluster analysis. Two major patient clusters differed in PR-induced autophagy (P < 0.001), myogenesis (P = 0.014), glucocorticoid signalling (P < 0.001), and oxidative metabolism regulation (P < 0.001), with Cluster 1 (C1; n = 29) overall displaying a more pronounced change in marker expression than Cluster 2 (C2; n = 16). General baseline characteristics did not differ between clusters. Following PR, both 6 min walking distance (+26.5 ± 8.3 m, P = 0.003) and peak load on the cycle ergometer test (+9.7 ± 1.9 W, P < 0.001) were improved. However, the functional improvement was more pronounced in C1, as a higher percentage of patients exceeded the minimal clinically important difference in peak workload (61 vs. 21%, P = 0.022) and both peak workload and 6 min walking test (52 vs. 8%, P = 0.008) upon PR.

CONCLUSIONS

We identified patient groups with distinct skeletal muscle molecular responses to rehabilitation, associated with differences in functional improvements upon PR.

Relationship between endothelial function and skeletal muscle strength in community dwelling elderly women

BACKGROUND

The aim of this study is to determine whether there is correlation between endothelial function and skeletal muscle function measured by hand grip strength in elderly women.

METHODS

This cross-sectional study used data of NAMGARAM-2 cohort. The NAMGARAM-2 cohort consisted of a group of people living in three rural communities. They were enrolled for studies on activity limitation due to age-related musculoskeletal disorders including knee osteoarthritis, osteoporosis, and sarcopenia. They were residents aged 40 years or older. They agreed to participate in this cohort from March 2016 to May 2017. Peripheral endothelial function was assessed by reactive hyperaemia-peripheral arterial tonometry using EndoPAT2000 system. Hand grip strength was measured using a digital hand dynamometer.

RESULTS

Endothelial function index assessed by EndoPAT was worse in the low grip strength group than that in the normal group of elderly women (1.54 ± 0.51 in the low grip strength group vs. 1.77 ± 0.67 in the normal group, P = 0.003). There was a positive correlation between hand grip strength and endothelial function (r = 0.176, P = 0.007). On stepwise multivariate analysis, endothelial dysfunction (reactive hyperaemia-peripheral arterial tonometry index < 1.67) significantly increased the risk of low hand grip strength (odds ratio = 2.019; 95% confidence interval = 1.107-3.682; P = 0.022).

CONCLUSIONS

Endothelial function and skeletal muscle strength had a significant correlation in elderly women, providing additional support for the relevant role of vascular system in sarcopenia.

Ectopic adiposity and cardiometabolic health in COPD

Rationale

Obesity/overweight is the most prevalent body composition abnormality in COPD. However, little is known about the impact of fat distribution on cardiometabolic health in COPD.

Objective

To study the associations between ectopic adiposity, cardiometabolic health, and COPD.

Methods

A total of 263 subjects (166 males; age=65±9 years) were randomly selected from the general population. Subjects were classified as non-COPD controls and COPD, according to the Global initiative for chronic Obstructive Lung Disease (GOLD) classification, and the presence of cardiometabolic comorbidities was recorded. Ectopic fat accumulation was documented from computed tomography measurements of visceral adipose tissue cross-sectional areas and muscle mean attenuation, assessed at L4–L5. Blood glucose, lipid, and adipokine profiles were also evaluated.

Results

After correcting for age, sex, and tobacco exposure, visceral adipose tissue cross-sectional area was higher in GOLD 2+ compared to GOLD 1 individuals. Consistent with this, mean muscle tissue attenuation was lower in GOLD 2+ vs GOLD 1 and non-COPD controls (P<0.001). In multiple regression models, visceral adipose tissue cross-sectional area was strongly associated with hypertension (P<0.001) and diabetes (P<0.001), while muscle attenuation was associated with coronary artery disease (P<0.001). Blood glucose, lipid, and adipokine profiles were similar across groups with the exception of leptin level which was higher in GOLD 2+ subjects compared to GOLD 1 and controls.

Conclusion

GOLD 2+ COPD was associated with ectopic fat accumulation which modulated cardiometabolic health.

Molecular signalling towards mitochondrial breakdown is enhanced in skeletal muscle of patients with chronic obstructive pulmonary disease (COPD)

Loss of skeletal muscle mitochondrial oxidative capacity is well-established in patients with COPD, but the role of mitochondrial breakdown herein is largely unexplored. Currently, we studied if mitochondrial breakdown signalling is increased in skeletal muscle of COPD patients and associates with the loss of mitochondrial content, and whether it is affected in patients with iron deficiency (ID) or systemic inflammation. Therefore, mitophagy, autophagy, mitochondrial dynamics and content markers were analysed in vastus lateralis biopsies of COPD patients (N = 95, FEV₁% predicted: 39.0 [31.0–53.6]) and healthy controls (N = 15, FEV₁% predicted: 112.8 [107.5–125.5]). Sub-analyses were performed on patients stratified by ID or C-reactive protein (CRP). Compared with controls, COPD patients had lower muscle mitochondrial content, higher BNIP3L and lower FUNDC1 protein, and higher Parkin protein and gene-expression. BNIP3L and Parkin protein levels inversely correlated with mtDNA/gDNA ratio and FEV₁% predicted. ID-COPD patients had lower BNIP3L protein and higher BNIP3 gene-expression, while high CRP patients had higher BNIP3 and autophagy-related protein levels. In conclusion, our data indicates that mitochondrial breakdown signalling is increased in skeletal muscle of COPD patients, and is related to disease severity and loss of mitochondrial content. Moreover, systemic inflammation is associated with higher BNIP3 and autophagy-related protein levels.

Resveratrol for patients with chronic obstructive pulmonary disease: hype or hope?

PURPOSE OF REVIEW

Chronic obstructive pulmonary disease (COPD) is a progressive lung disease with a high prevalence of extrapulmonary manifestations and, frequently, cardiovascular comorbidity. Resveratrol is a food-derived compound with anti-inflammatory, antioxidant, metabolic and cardioprotective potential. Therefore, resveratrol might improve the pulmonary as well as extrapulmonary pathology in COPD. In this review, we will evaluate knowledge on the effects of resveratrol on lung injury, muscle metabolism and cardiovascular risk profile and discuss if resveratrol is a hype or hope for patients with COPD.

RECENT FINDINGS

Experimental models of COPD consistently show decreased inflammation and oxidative stress in the lungs after resveratrol treatment. These beneficial anti-inflammatory and antioxidant properties of resveratrol can indirectly also improve both skeletal and respiratory muscle impairment in COPD. Recent clinical studies in non-COPD populations show improved mitochondrial oxidative metabolism after resveratrol treatment, which could be beneficial for both lung and muscle impairment in COPD. Moreover, preclinical studies suggest cardioprotective effects of resveratrol but results of clinical studies are inconclusive.

SUMMARY

Resveratrol might be an interesting therapeutic candidate to counteract lung and muscle impairments characteristic to COPD. However, there is no convincing evidence that resveratrol will significantly decrease the cardiovascular risk in patients with COPD.

Prevalence and Associated Risk Factors of Sarcopenia in Female Patients with Osteoporotic Fracture

Background

We determined the prevalence of sarcopenia according to fracture site and evaluated the associated risk factors in female patients with osteoporotic fractures.

Methods

A total of 108 patients aged 50 years or older with an osteoporotic fracture (hip, spine, or wrist) were enrolled in this retrospective observational study. A diagnosis of sarcopenia was confirmed using whole-body densitometry for skeletal muscle mass measurement. Logistic regression analysis was used to analyze the risk factors for sarcopenia.

Results

Of 108 female patients treated for osteoporotic fractures between January 2016 and June 2017, sarcopenia was diagnosed in 39 (36.1%). Of these, 41.5% (17/41) had hip fractures, 35% (14/40) had spine fractures, and 29.6% (8/27) had distal radius fractures. Body mass index (BMI; P=0.036) and prevalence of chronic kidney disease (CKD; P=0.046) and rheumatoid arthritis (P=0.051) were significantly different between the groups. In multivariable analysis, BMI (odds ratio [OR], 0.76; 95% confidence interval [CI], 0.55–1.05, P=0.098) and CKD (OR 2.51; 95% CI, 0.38–16.2; P=0.233) were associated with an increased risk of sarcopenia; however, this was not statistically significant.

Conclusions

This study evaluated the prevalence of sarcopenia according to the fracture site and identified associated risk factors in patients with osteoporotic fractures. A longterm, observational study with a larger population is needed to validate our results.

Osteosarcopenia in Patients with Hip Fracture Is Related with High Mortality

BACKGROUND

This study evaluated the prevalence of osteosarcopenia, as well as the relationship between one-year mortality and osteosarcopenia, as defined by criteria of the Asian Working Group on Sarcopenia in patients age 60 or older with hip fracture.

METHODS

A total of 324 patients age 60 years or older with hip fracture were enrolled in this retrospective observational study. The main outcome measure was the prevalence of osteosarcopenia, as well as the relationship between osteosarcopenia and 1-year mortality. The diagnosis of sarcopenia was carried out according to the Asian Working Group on Sarcopenia. Whole body densitometry analysis was used for skeletal muscle mass measurement and muscle strength were evaluated by handgrip testing. Mortality was assessed at the end of 1-year. Cox regression analysis was utilized to analyze the risk factor of osteosarcopenia.

RESULTS

Of 324 patients with hip fracture, 93 (28.7%) were diagnosed with osteosarcopenia. In total, 9.0% died during the one-year follow-up. A one-year mortality of osteosarcopenia (15.1%) was higher than that of other groups (normal: 7.8%, osteoporosis only: 5.1%, sarcopenia only: 10.3%). Osteosarcopenia had a 1.8 times higher mortality rate than non-osteosarcopenia.

CONCLUSION

The present study demonstrates that the prevalence of osteosarcopenia is not rare, and has a higher mortality rate than the non-osteosarcopenia group at the 1-year follow-up period. This is the first study evaluating the relationship between mortality and osteosarcopenia in patients with hip fracture.

Increased Myogenic and Protein Turnover Signaling in Skeletal Muscle of Chronic Obstructive Pulmonary Disease Patients With Sarcopenia

BACKGROUND

Sarcopenia was recently recognized as an independent condition by an International Classification of Diseases, Tenth Revision, Clinical Modification code, and is a frequently observed comorbidity in chronic obstructive pulmonary disease (COPD). Muscle mass is primarily dictated by the balance between protein degradation and synthesis, but their relative contribution to sarcopenia is unclear.

OBJECTIVE

We aimed to assess potential differential molecular regulation of protein degradation and synthesis, as well as myogenesis, in the skeletal muscle of COPD patients with and without sarcopenia.

METHODS

Muscle biopsies were obtained from the vastus lateralis muscle. Patients with COPD were clustered based on sarcopenia defined by low appendicular skeletal muscle mass index (nonsarcopenic COPD, n = 53; sarcopenic COPD, n = 39), and compared with healthy nonsarcopenic controls (n = 13). The mRNA and protein expression of regulators and mediators of ubiquitin-proteasome system (UPS), autophagy-lysosome system (autophagy), and protein synthesis were analyzed. Furthermore, mRNA expression of myogenesis markers was assessed.

RESULTS

UPS signaling was unaltered, whereas indices of UPS regulation (eg, FOXO1 protein; p-FOXO3/FOXO3), autophagy signaling (eg, LC3BII/I; p-ULK1[Ser757]/ULK1), and protein synthesis signaling (eg, AKT1; p-GSK3B/GSK3B; p-4E-BP1/4E-BP1) were increased in COPD. These alterations were even more pronounced in COPD patients with sarcopenia (eg, FOXO1 protein; p-FOXO1/FOXO1; LC3BII/I; p-ULK(Ser555); p-AKT1/AKT1; AKT1; p-4E-BP1). Furthermore, myogenic signaling (eg, MYOG) was increased in COPD despite a concomitant increase of myostatin (MSTN) mRNA expression, with no difference between sarcopenic and nonsarcopenic COPD patients.

CONCLUSION

Together with elevated myogenic signaling, the increase in muscle protein turnover signaling in COPD, which is even more prominent in COPD patients with sarcopenia, reflects molecular alterations associated with muscle repair and remodeling.