Body composition and sarcopenia in patients with chronic obstructive pulmonary disease

Investigation of nutrition status and analysis of 180-day readmission factors in elderly hospitalized patients with COPD

BACKGROUND AND OBJECTIVE

Malnutrition is prevalent among elderly patients with COPD, who also experience a high rate of readmission. Therefore, it is imperative to investigate the nutrition status of these patients, identify risk factors for readmission, and offer insights for clinical management. To achieve this, a cross-sectional study was conducted to investigate factors influencing nutrition status using GLIM criteria and explore the 180-day readmission factors among hospitalized elderly COPD patients.

METHORDS AND RESULTS

The data were collected from a hospital in Southwest China, encompassing a cohort of 319 eligible patients. Among elderly hospitalized COPD patients, the prevalence of malnutrition was 49.53% (158/319). Multivariate logistic regression revealed malnutrition (OR = 3.184), very severe airway obstruction (OR = 3.735), and Number of comorbidities ≥ 3 (OR = 5.754) as significant risk factors for 180-day readmission.

CONCLUSIONS

These findings suggest that malnutrition is a prevalent issue among elderly hospitalized patients with COPD and constitutes one of the risk factors contributing to the 180-day readmission rate. Therefore, timely identification and treatment for malnourished patients are crucial.

Phase angle as an indicator of sarcopenia and malnutrition in patients with chronic obstructive pulmonary disease

BACKGROUND

Phase angle (PhA), which is measured using bioelectrical impedance analysis, is an indicator of muscle quality and malnutrition. PhA has been shown to be correlated with sarcopenia and malnutrition; however, studies on patients with chronic obstructive pulmonary disease (COPD) are limited. In this study, we investigated the correlation between PhA and sarcopenia and malnutrition and determined the cutoff values of PhA for those in patients with COPD.

METHODS

This study included 105 male patients with COPD (mean age 75.7 ± 7.7 years, mean forced expiratory volume in 1s % predicted [%FEV1] 57.0 ± 20.1%) and 12 male controls (mean age 74.1 ± 3.8 years) who were outpatients between December 2019 and March 2024. PhA was measured using the InBody S10, and its correlation with sarcopenia and malnutrition was assessed. The cutoff PhA values for sarcopenia and malnutrition were determined using receiver operating characteristic curves.

RESULTS

The prevalence rates of sarcopenia and malnutrition were 31% and 22%, respectively, in patients with COPD. PhA significantly correlated with sarcopenia- and malnutrition-related indicators. Multivariate logistic regression analysis independently correlated PhA with sarcopenia and malnutrition. The cutoff values of the PhA for sarcopenia and malnutrition were 4.75° (AUC = 0.78, 95% CI = 0.68-0.88) and 4.25° (AUC = 0.75, 95% CI = 0.63-0.86), respectively.

CONCLUSIONS

PhA was significantly correlated with sarcopenia and malnutrition in Japanese patients with COPD and may be a useful diagnostic indicator.

Prevalence and clinical characteristics of Sarcopenia in older adult patients with stable chronic obstructive pulmonary disease: a cross-sectional and follow-up study

BACKGROUND

The relationship between sarcopenia and chronic obstructive pulmonary disease (COPD) has been increasingly reported, and there is some overlap regarding their clinical features and pulmonary rehabilitation (PR) strategies. No Korean study has reported the actual prevalence of sarcopenia in patients with stable COPD who are recommended for pulmonary rehabilitation. This study evaluated the prevalence and clinical features of sarcopenia in older adult outpatients with stable COPD and the changes after 6 months.

METHODS

In this cross-sectional and 6-month follow-up study, we recruited 63 males aged ≥ 65 diagnosed with stable COPD. Sarcopenia was diagnosed using the AWGS 2019 criteria, which included hand grip strength testing, bioelectrical impedance analysis, Short Physical Performance Battery administration, and Strength, Assistance with walking, Rising from a chair, Climbing stairs, and Falling screening tool administration. A 6-minute walk test (6 MWT) was conducted, forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), maximal inspiratory and expiratory pressures (MIP and MEP, respectively) and peak expiratory flow (PEF) were assessed, and patient-reported questionnaires were administered.

RESULTS

At baseline, 14 (22%) patients were diagnosed with possible sarcopenia, and eight (12.6%) were diagnosed with sarcopenia. There were significant differences in the age; body mass index; Body mass index, airflow Obstruction, Dyspnea, and Exercise index; modified Medical Research Council dyspnea scores; and International Physical Activity Questionnaire scores between the normal and sarcopenia groups. Whole-body phase angle, MIP, MEP, PEF, and 6-minute walk distance (6 MWD) also showed significant differences. Over 6 months, the proportion of patients with a reduced FEV1 increased; however, the proportion of patients with sarcopenia did not increase.

CONCLUSION

A relatively low prevalence of sarcopenia was observed in older adult outpatients with stable COPD. No significant change in the prevalence of sarcopenia was found during the 6-month follow-up period.

TRIAL REGISTRATION

The study was registered with the Clinical Research Information Service (KCT0006720). Registration date: 30/07/2021.

Chronic obstructive pulmonary disease as a risk factor for sarcopenia: A systematic review and meta-analysis

Sarcopenia prevalence and its risk factors in chronic obstructive pulmonary disease (COPD) vary partly due to definition criteria. This systematic review aimed to identify the prevalence and risk factors of sarcopenia in COPD patients. This review was registered in PROSPERO (CRD42022310750). Nine electronic databases were searched from inception to September 1st, 2022, and studies related to sarcopenia and COPD were identified. Study quality was assessed using a validated scale matched to study designs, and a meta-analysis was performed to evaluate sarcopenia prevalence. COPD patients with sarcopenia were compared to those without sarcopenia for BMI, smoking, and mMRC. The current meta-analysis included 15 studies, with a total of 7,583 patients. The overall sarcopenia prevalence was 29% [95% CI: 22%-37%], and the OR of sarcopenia in COPD patients was 1.51 (95% CI: 1.19-1.92). The meta-analysis and systematic review showed that mMRC (OR = 2.02, P = 0.04) and age (OR = 1.15, P = 0.004) were significant risk factors for sarcopenia in COPD patients. In contrast, no significant relationship was observed between sarcopenia and smoking and BMI. Nursing researchers should pay more attention to the symptomatic management of COPD and encourage patients to participate in daily activities in the early stages of the disease.

HDAC9 inhibition reduces skeletal muscle atrophy and enhances regeneration in mice with cigarette smoke-induced COPD

Cigarette smoke (CS) is the major risk factor for chronic obstructive pulmonary disease (COPD), and sarcopenia is one of the significant comorbidities of COPD. However, the pathogenesis of CS-related deficient skeletal muscle regeneration has yet to be clarified. The impact of CS on myoblast differentiation was examined, and then we determined which HDAC influenced the myogenic process and muscle atrophy in vitro and in vivo. Finally, we further investigated the potential mechanisms via RNA sequencing. Long-term CS exposure activated skeletal muscle primary satellite cells (SCs) while inhibiting differentiation, and defective myogenesis was also observed in C2C12 cells treated with CS extract (CSE). The level of HDAC9 changed in vitro and in vivo in CS exposure models as well as COPD patients, as detected by bioinformatics analysis. Our data showed that CSE impaired myogenic capacity and myotube formation in C2C12 cells via HDAC9. Moreover, inhibition of HDAC9 in mice exposed to CS prevented skeletal muscle dysfunction and promoted SC differentiation. The results of RNA-Seq analysis and verification indicated that HDAC9 knockout improved muscle differentiation in CS-exposed mice, probably by acting on the AKT/mTOR pathway and inhibiting the P53/P21 pathway. More importantly, the serum of HDAC9 KO mice exposed to CS alleviated the differentiation impairment of C2C12 cells caused by serum intervention in CS-exposed mice, and this effect was inhibited by LY294002 (an AKT/mTOR pathway inhibitor). These results suggest that HDAC9 plays an essential role in the defective regeneration induced by chronic exposure to CS.

Postural balance in COPD with obstructive sleep apnoea: a cross-sectional study

Objective

The aim of this study was to assess the postural balance in COPD patients with obstructive sleep apnoea (OSA). Physical activity, anxiety and depression symptoms, mood, and falls were also assessed in this population.

Methods

Moderate to severe COPD patients were assessed for laboratory and clinical postural balance (force platform and mini-balance evaluation systems test (Mini-BESTest)), physical activity (accelerometry), OSA (polysomnography), sleep quality (Pittsburgh Sleep Quality Index), sleepiness (Epworth Sleepiness Scale), anxiety and depression symptoms (Hospital Anxiety and Depression Scale), dyspnoea (modified Medical Research Council), clinical status (COPD Assessment Test) and mood (Brunel Mood Scale). Self-reported falls were recorded for 6 months via phone calls.

Results

COPD patients (n=70) were divided according to the polysomnography findings into the no OSA (n=30), mild OSA (n=25), and moderate to severe OSA (n=15) groups. Compared to patients with no OSA, those with moderate to severe OSA (msOSA group) presented median (interquartile range) increased path length (30.5 (23.9-34.5) cm versus 39.0 (30.6-52.6) cm, anteroposterior displacement (1.89 (1.39-2.31) cm versus 2.54 (2.06-2.83) cm and postural adjustment velocity (1.02 (0.80-1.15) cm·s-1 versus 1.30 (1.02-1.76) cm·s-1) (p<0.05). No differences were observed in the Mini-BESTest scores among the groups. The msOSA group presented a greater number of recurrent fallers in the first follow-up trimester. No association was observed between postural balance and age and pulmonary function.

Conclusion

Individuals with COPD and moderate to severe OSA present changes in postural balance, including broader oscillation, faster postural adjustments and a greater risk of falls than those with no OSA. Physical activity, anxiety and depression symptoms, and mood are similar between COPD patients with and without OSA.

The triad of physiological challenges: investigating the intersection of sarcopenia, malnutrition, and malnutrition-sarcopenia syndrome in patients with COPD - a cross-sectional study

BACKGROUND

One of the most prevalent respiratory disorders in modern society is chronic obstructive pulmonary disease (COPD). Frequent comorbidities in patients with COPD are abnormal nutritional status and body composition variations. Malnutrition-sarcopenia syndrome, which occurs when the 2 conditions - malnutrition and sarcopenia - coexist, raises the risk of death more than either condition alone. The current study sought to determine the prevalence of malnutrition, sarcopenia, and malnutrition-sarcopenia syndrome in patients with COPD as well as the association between these diseases and the severity of COPD.

METHODS

The study was an analytical cross-sectional study conducted on hospitalized patients with COPD. The sample size of the study was calculated to be 160. A self-structured questionnaire was used to collect the data, containing sociodemographic characteristics, clinical profiles, anthropometric assessment, and bioimpedance indices. Sarcopenia was diagnosed with low muscle strength and muscle mass by the EWGSOP2 recommendations. Muscle mass is measured by BIA and muscle strength (Handgrip) was measured by a Hand Dynamometer. Assessment of the risk of malnutrition was performed using the Mini Nutritional Assessment-Short Form questionnaire and was confirmed by GLIM criteria. The COPD assessment test (CAT) tool determined the severity of the condition. For the data analysis, comparisons were made using Student's t test and Mann-Whitney test in bivariate analysis. Multivariate logistic regression analyses were performed considering the outcomes of patients with COPD by CAT scores, prolonged length of stay, and hospital readmission 6 months after discharge.

RESULTS

The mean age of the participants was 48 ± 5 years. Approximately 61.9% were found to be sarcopenic. Approximately 45.6% of participants had malnutrition. Malnutrition sarcopenia syndrome was diagnosed in 32.5% of patients. The study analysis revealed that patients with COPD with malnutrition-sarcopenia syndrome had more than twice the odds of prolonged hospital stay, re-admission within 6 months, and higher CAT scores.

CONCLUSION

The study revealed a high prevalence of sarcopenia, malnutrition, and malnutrition sarcopenia syndrome in patients with COPD. These conditions were found to be statistically significant with prolonged length of stay, re-admission within 6 months, and CAT scores. The findings highlight the importance of addressing these conditions as part of the management of the patients.

The association between walking pace and hand grip strength with the risk of chronic obstructive pulmonary disease: a bidirectional Mendelian randomization study

BACKGROUND

Chronic Obstructive Pulmonary Disease (COPD) currently ranks as the third leading cause of mortality worldwide, imposing substantial burdens on societal and individual health. Amongst health research tools, walking pace (WP) and hand grip strength (HGS) are cornerstones, extensively associated with diverse health conditions. However, the intricate interplay between these factors and COPD risk remains ambiguous. This study aims to elucidate the causal association of WP, HGS, with COPD risk through a bidirectional Mendelian randomization (MR) approach.

METHODS

Bidirectional MR analysis was performed using Genome-wide association study (GWAS) data of European individuals for WP, HGS, and COPD. Inverse Variance Weighted (IVW) served as the primary MR analysis approach. To supplement the IVW findings, four additional MR methods [MR-Egger, weighted median, maximum likelihood, simple median] were used. To assess heterogeneity and pleiotropy, sensitivity analyses were performed. In addition, multivariate MR (MVMR) analysis was used to assess causality after adjustment for potential confounders.

RESULTS

IVW method results show a significant negative association between WP and COPD risk in both initial (genome-wide threshold, odds ratio (OR) = 0.21, 95% confidence interval (CI) 0.09-0.51, P = 5.06 × 10- 4) and secondary (locus-wide threshold, OR = 0.27, 95%CI: 0.18-0.41, P = 4.88 × 10- 10) MR analysis. The reverse MR analysis suggested that COPD also diminishes WP. Additionally, a causal risk reduction for COPD with right HGS (OR = 0.74, 95% CI: 0.58-0.94, P = 1.44 × 10- 2) was only found in secondary MR analysis. The outcomes of the four additional MR methods also suggested similar causal relationships, and sensitivity analyses endorsed their robustness. Lastly, the MVMR analysis demonstrated that the WP's effect on reducing COPD risk persisted independently of potential confounding variables.

CONCLUSION

A bidirectional causal relationship exists between typical WP and COPD risk. Conversely, a decrease in right HGS is unidirectionally associated with an increased risk of COPD. The study suggests that WP may serve as a predictive factor for COPD or as a simple evaluative indicator for prognosis.

Association between appendicular lean mass and chronic obstructive pulmonary disease: epidemiological cross-sectional study and bidirectional Mendelian randomization analysis

Background

The association of BMI with COPD, and sarcopenia in COPD have been both confirmed by several studies, but research on the relationship and causality of body lean mass and the risk of chronic obstructive pulmonary disease (COPD) remains to be discovered. The purpose of this study was to explore the association between lean mass and COPD risk as well as to further examine the causal relationship in the findings.

Methods

Three thousand four hundred fifty-nine participants from NHANES 2013-2018 were included in the epidemiological cross-sectional study to assess the association between relative lean mass and COPD by restricted spline analysis (RCS) and weighted multiple logistic regression. Furthermore, to verify the causality between lean mass and COPD, a two-sample Mendelian randomization (MR) with inverse variance weighting (IVW) method was used to analyze GWAS data from European ancestry. Genetic data from the United Kindom Biobank for appendicular lean mass (450,243 cases) and lung function (FEV₁/FVC) (400,102 cases) together with the FinnGen platform for COPD (6,915 cases and 186,723 controls) were used for MR.

Results

Weighted multiple logistic regression showed a significant correlation between relative appendicular lean mass and COPD after adjusting for confounders (OR = 0.985, 95% CI: 0.975-0.995). Compared to the lower mass (155.3-254.7) g/kg, the high mass (317.0-408.5) g/kg of appendicular lean apparently decreases the risk of COPD (OR = 0.214, 95% CI: 0.060-0.767). Besides, in the analysis of MR, there was a forward causality between appendicular lean mass and COPD (IVW: OR = 0.803; 95%CI: 0.680-0.949; p = 0.01), with a weak trend of causality to lung function.

Conclusion

Our study not only found an inverse association between appendicular lean mass and COPD but also supported a unidirectional causality. This provided possible evidence for further identification of people at risk for COPD and prevention of COPD based on limb muscle exercise and nutritional supplementation to maintain skeletal muscle mass.

Nutritional State and COPD: Effects on Dyspnoea and Exercise Tolerance

Chronic Obstructive Pulmonary Disease (COPD) is a disease that is spreading worldwide and is responsible for a huge number of deaths annually. It is characterized by progressive and often irreversible airflow obstruction, with a heterogeneous clinical manifestation based on disease severity. Along with pulmonary impairment, COPD patients display different grades of malnutrition that can be linked to a worsening of respiratory function and to a negative prognosis. Nutritional impairment seems to be related to a reduced exercise tolerance and to dyspnoea becoming a major determinant in patient-perceived quality of life. Many strategies have been proposed to limit the effects of malnutrition on disease progression, but there are still limited data available to determine which of them is the best option to manage COPD patients. The purpose of this review is to highlight the main aspects of COPD-related malnutrition and to underline the importance of poor nutritional state on muscle energetics, exercise tolerance and dyspnoea.

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.

Understanding the role of smoking and chronic excess alcohol consumption on reduced caloric intake and the development of sarcopenia

This narrative review provides mechanistic insight into the biological link between smoking and/or chronic excess alcohol consumption, and increased risk of developing sarcopenia. Although the combination of excessive alcohol consumption and smoking is often associated with ectopic adipose deposition, this review is focused on the context of a reduced caloric intake (leading to energy deficit) that also may ensue due to either lifestyle habit. Smoking is a primary cause of periodontitis and chronic obstructive pulmonary disease that both induce swallowing difficulties, inhibit taste and mastication, and are associated with increased risk of muscle atrophy and mitochondrial dysfunction. Smoking may contribute to physical inactivity, energy deficit via reduced caloric intake, and increased systemic inflammation, all of which are factors known to suppress muscle protein synthesis rates. Moreover, chronic excess alcohol consumption may result in gut microbiota dysbiosis and autophagy-induced hyperammonemia, initiating the up-regulation of muscle protein breakdown and down-regulation of muscle protein synthesis via activation of myostatin, AMPK and REDD1, and deactivation of IGF-1. Future research is warranted to explore the link between oral healthcare management and personalised nutrition counselling in light of potential detrimental consequences of chronic smoking on musculoskeletal health outcomes in older adults. Experimental studies should investigate the impact of smoking and chronic excess alcohol consumption on the gut-brain axis, and explore biomarkers of smoking-induced oral disease progression. The implementation of behavioural change interventions and health policies regarding smoking and alcohol intake habits may mitigate the clinical and financial burden of sarcopenia on the healthcare system.

Validation of Asian Body Mass Index Cutoff Values for the Classification of Malnutrition Severity According to the Global Leadership Initiative on Malnutrition Criteria in Patients with Chronic Obstructive Pulmonary Disease Exacerbations

Low body mass index (BMI) is an independent predictor of prolonged hospital stay and mortality in patients with chronic obstructive pulmonary disease (COPD). However, to the best of our knowledge, no studies have examined the validity of Asian BMI cutoff values for classifying severity based on the Global Leadership Initiative on Malnutrition (GLIM) criteria in patients with acute COPD exacerbations. This study sought to validate whether Asian BMI cutoff values can accurately predict 30-day in-hospital mortality, length of stay, and 90-day readmission outcomes for patients with acute COPD exacerbations. The present retrospective cohort study was conducted using a large claims database created by the JMDC. Patients were classified into three groups according to the severity of low BMI assessed using Asian BMI cutoff values. As a result, 624 (29.4%) had severely low BMI, and 444 (20.9%) had moderately low BMI. The severity of low BMI, as assessed by the Asian BMI cutoff values used in the GLIM criteria, was independently associated with 30-day in-hospital mortality (moderately low BMI: HR, 1.87; 95% CI, 1.13−3.08; p = 0.014 and severely low BMI: HR, 2.55; 95% CI, 1.66−3.92; p < 0.001). The Asian BMI cutoff values used to classify the severity of malnutrition in the GLIM criteria are clinically functional for predicting the prognosis of patients with acute COPD exacerbations.

Relationship of body mass index on activities of daily living in hospitalized patients with chronic obstructive pulmonary disease

BACKGROUND

Weight loss and low lean body mass in patients with chronic obstructive pulmonary disease (COPD) are associated with increased mortality; however, the association between body mass index (BMI) and physical ability remains undetermined. We aimed to investigate the effect of BMI on activities of daily living (ADL) in hospitalized patients with COPD.

METHODS

We used the Japan Medical Data Center's hospital-based database to extract data on hospitalized patients aged ≥ 20 years admitted for COPD between April 2014 and December 2018. The primary outcome was the presence or absence of deterioration in the Barthel Index score for ADLs at discharge compared with that at admission. Secondary outcomes were the length of hospital stay, readmission within 30 days, and the number of drugs administered on admission.

RESULTS

We identified 6529 patients with COPD from the Diagnosis Procedure Combination database, of which 3476 were analyzed (excluded: n = 5, ages < 20 years; n = 3048, missing entries). Barthel Index scores tended to decline in patients with BMI < 18.5 kg/m² (odds ratio, OR: 2.030, p < 0.001) and Hugh-Jones grade 4 (OR: 1.79, p = 0.05) and grade 5 (OR: 2.15, p = 0.01), but not in the obese group (p = 0.598). The low-weight group had a significantly longer hospital stay (p < 0.001) at 14 (8-25) days with greater readmissions within 30 days (6.3%, p < 0.001).

CONCLUSION

Low BMI is associated with lower Barthel Index scores, longer hospital stays, requiring readmissions within 30 days of discharge.

Hepatic drug metabolism in older people with body composition changes

AIM

Dosage adjustment is essential in older individuals because they are prone to experience a decline in liver function and changes in body composition. However, quantitative tests or equations for evaluating the activity of hepatic drug metabolism have not yet been clearly established. We examined hepatic drug metabolism activities in older individuals, focusing on changes in body composition parameters.

METHODS

Lansoprazole and nifedipine, substrates of the metabolic enzymes cytochrome P450 (CYP) 2C19 and 3A4, respectively, were selected to study hepatic drug metabolism. Residual samples from blood test for older patients were evaluated to determine drug metabolism. The body composition of relevant patients was determined by analyzing characteristic parameters of skeletal muscle mass index (SMI), handgrip strength (HGS) and hepatic steatosis index (HSI). The differences in hepatic drug metabolism were studied statistically among categories in terms of the cut-off value of these parameters.

RESULTS

Older male patients receiving lansoprazole and nifedipine in the low SMI (<7.0 kg/m² ) category showed an 85-90% reduction in respective CYP2C19 and CYP3A4 metabolic activities compared with the normal SMI category. For the female patients, CYP2C19 and CYP3A4 metabolic activities showed no significant correlation with SMI and HGS. Fatty liver disease (HSI ≥36) was found to reduce CYP2C19 metabolic activity particularly in older female patients.

CONCLUSIONS

Low CYP2C19 metabolic activity was statistically correlated with low SMI in male patients and high HSI in female patients, whereas low CYP3A4 metabolic activity was statistically correlated with low HGS in male patients. Geriatr Gerontol Int 2022; 22: 449-454.

Malnutrition, Sarcopenia, and Malnutrition-Sarcopenia Syndrome in Older Adults with COPD

Purpose: Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death in the world population. In addition to airflow obstruction, COPD is associated with multiple systemic manifestations, including impaired nutritional status or malnutrition and changes in body composition (low muscle mass, LMM). Poor nutritional status and sarcopenia in subjects with COPD leads to a worse prognosis and increases health-related costs. Data from previous studies indicate that 30–60% of subjects with COPD are malnourished, 20–40% have low muscle mass, and 15–21.6% have sarcopenia. This study aimed to assess the prevalence of malnutrition, sarcopenia, and malnutrition-sarcopenia syndrome in elderly subjects with COPD and investigate the relationship between COPD severity and these conditions.Patients and methods: A cross-sectional study involving 124 patients with stable COPD, aged ≥60, participating in a stationary pulmonary rehabilitation program. Nutritional status was assessed following the Global Leadership Initiative on Malnutrition (GLIM) criteria and sarcopenia with the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) criteria. The results of pulmonary function tests and exercise capacity were obtained from the hospital database. Results: 22.6% of participants had malnutrition according to the GLIM criteria. Subjects with malnutrition had lower gait speed (p = 0.0112) and worse results of the Six Minute Walk Test. Sixteen participants (12.9%) had sarcopenia; 12 subjects with sarcopenia had concomitant malnutrition. The prevalence of severe and very severe obstruction (GOLD3/GOLD4) was 91.7%. It was significantly higher in patients with malnutrition-sarcopenia syndrome. Conclusions: Malnutrition was found in nearly one out of four subjects with COPD, while sarcopenia was one out of seven patients. About 10% of our study sample had malnutrition-sarcopenia syndrome. The prevalence of severe and very severe obstruction was significantly higher in patients with malnutrition-sarcopenia syndrome.

Cachexia Versus Sarcopenia in Clinical Characteristics and Prognostic Value After Radical Gastrectomy for Gastric Cancer: A Large-Scale Prospective Study

BACKGROUND

Sarcopenia and cachexia are two predictors of adverse clinical outcomes, but they are partly overlapping. We aimed to compare the characteristics and prognostic value of cachexia and sarcopenia in patients after gastrectomy.

METHODS

From 2014 to 2019, a total of 1215 gastric cancer patients were enrolled. Cachexia and sarcopenia were diagnosed according to the most recent consensus definitions. Baseline characteristics and clinical outcomes were compared between the two groups. Risk factors of survival were evaluated by Cox regression analysis.

RESULTS

Of all patients, 26.5% were diagnosed with cachexia and 19.8% were diagnosed with sarcopenia. Sarcopenia was more prevalent in elderly patients, while cachexia was prone to occur in patients with TMN stage III. Survival curves showed that sarcopenia had adverse effects in patients with TMN stage I and II-III, while cachexia was only associated with poor survival at stages II-III. For the entire cohort, both cachexia and sarcopenia were adverse factors for prognosis. However, for stage I patients, sarcopenia was an independent predictor for overall survival (OS) (HR = 4.939, P < 0.001) and disease-free survival (DFS) (HR = 4.256, P < 0.001), but not cachexia; for stage II-III patients, cachexia was an independent predictor for OS (HR = 1.538, P < 0.001) and DFS (HR = 1.473, P = 0.001), but not sarcopenia.

CONCLUSIONS

Sarcopenia and cachexia have different clinical characteristics and prognostic values. For patients with early stage gastric cancer, detection for sarcopenia was more meaningful than cachexia. However, the prognostic significance of cachexia exceeded sarcopenia in advanced cancer.

Prevalence, associated factors, and prognostic value of sarcopenia in patients with acute exacerbated chronic obstructive pulmonary disease: A cohort study

BACKGROUND AND AIMS

Besides pulmonary dysfunctions, patients with chronic obstructive pulmonary disease (COPD) also frequently have systemic comorbidities. Among these, sarcopenia is associated with worse pulmonary function and clinical outcomes. Patients with acute exacerbated COPD (AECOPD) have increased systemic inflammation, which can intensify muscle dysfunction. Therefore, the present study aimed to evaluate the prevalence of sarcopenia in AECOPD patients and assess the associated factors and their prognostic value. As a secondary aim, we also assessed the performance of calf circumference (CC) to diagnose this condition.

METHODS

Prospective cohort study in a Brazilian public hospital with AECOPD patients. Sarcopenia was assessed according to the recommendations from the European Working Group of Sarcopenia in Older People Consensus 2 (EWGSOP2); namely, reduced handgrip strength (HGS) combined with low fat-free mass index (FFMI) or CC. Data on clinical, nutritional, and sociodemographic features were collected. The evaluated clinical outcomes were the length of hospital stay (LOS), admission in intensive care units (ICUs), and in-hospital death.

RESULTS

Among 208 patients (54.8% females, 67.6 ± 10.1 years) evaluated, 16.3% presented sarcopenia. Malnutrition (odds ratio [OR] = 16.50, 95% confidence interval [CI] 3.58-76.08), and disease stages III-IV (OR = 4.05 95%CI 1.20-13.76) were associated with the presence of sarcopenia. The CC showed satisfactory performance in diagnosing sarcopenia as compared to FFMI as a marker of reduced muscle mass (kappa = 0.703; area under the receiver operating characteristic [AUC ROC] curve = 0.886; 95%CI 0.811-0.961). Sarcopenia was not associated with clinical outcomes.

CONCLUSION

Almost 20% of patients in this study presented sarcopenia. Malnutrition and advanced Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage were associated with increased chances of this condition in AECOPD patients. Reduced HSG combined with low CC may be an alternative when FFMI not be obtained for sarcopenia diagnosis.

Sarcopenia in older people with chronic airway diseases: the Rotterdam study

Sarcopenia is a heterogeneous skeletal muscle disorder involving the loss of muscle mass and function. However, the prevalence of sarcopenia based on the most recent definition remains to be determined in older people with chronic airway diseases. The aim was to evaluate sarcopenia prevalence and association with chronic airway diseases and its lung function in an older population, using the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) criteria. We performed a cross-sectional analysis in 5082 participants (mean age 69.0±8.8 years, 56% females) from the Rotterdam Study. Participants with interpretable spirometry and an available assessment of sarcopenia were included. The appendicular skeletal muscle mass index (ASMI) and handgrip strength (HGS) were assessed using dual-energy X-ray absorptiometry (DXA) and a hydraulic hand dynamometer, respectively. We analysed the association between sarcopenia and chronic airway diseases by using regression models adjusted for age, sex, smoking status, total fat percentage and other relevant confounders. Participants with chronic airway diseases had higher prevalence of probable sarcopenia (12.0%, 95% CI 10.2-13.8) and confirmed sarcopenia (3.0%, 95% CI 2.1-3.9) than without. Chronic airway diseases were associated with "probable sarcopenia" (OR 1.28, 95% CI 1.02-1.60), "confirmed sarcopenia" (OR 2.13, 95% CI 1.33-3.43), reduced HGS (β -0.51 (-0.90--0.11)) and reduced ASMI (β -0.19 (-0.25--0.14)). Forced expiratory volume in 1 s <80% was associated with lower HGS (β -1.03 (-1.75--0.31)) and lower ASMI (β -0.25 (-0.36--0.15)) than forced expiratory volume in 1 s ≥80%. Sarcopenia was prevalent and associated with chronic airway diseases among older population. These results suggest the need for early diagnosis of sarcopenia in older people with chronic airway diseases by applying EWGSOP2 recommendations.

Functional tests associated with sarcopenia in moderate chronic obstructive pulmonary disease

Objectives: To evaluate the association of physical and functional measures with sarcopenia in moderate chronic obstructive pulmonary disease (COPD) and to establish cutoff points for sarcopenia screening.Methods: The study included COPD with and without sarcopenia, of both sexes who were over 50 years old. Participants were assessed for lung function, body composition, grip strength, Short Physical Performance Battery (SPPB), 5-repetition, 10-repetition and 30-s sit-to-stand tests (5STS, 10STS, and 30STS, respectively). In addition, 6-min walking test, respiratory muscular strength, and physical activity level were tested.Results: The study had 35 participants, 24 men (68.6%) and moderate COPD (51.4%). COPD-sarcopenia showed lower values in lean mass, body fat and body mass alongside lower performance in 10 and 30 STS tests, SPPB and gait speed compared to non-sarcopenic group. The cutoff points with better sensitivity and specificity to identify sarcopenia were 10.88 and 34.14 s, 15 repetitions, and 10 points in the 5STS, 10STS, 30STS, and SPPB, respectively. The comparison of the receiver operating curves evidenced no differences between the functional tests. Only 30STS and SPPB showed acceptable discriminatory power.Conclusion: Functional tests, especially 30STS and SPPB, are simple and affordable tools for screening sarcopenia in COPD with moderate obstruction.

Tracking the carbons supplying gluconeogenesis

As the burden of type 2 diabetes mellitus (T2DM) grows in the 21st century, the need to understand glucose metabolism heightens. Increased gluconeogenesis is a major contributor to the hyperglycemia seen in T2DM. Isotope tracer experiments in humans and animals over several decades have offered insights into gluconeogenesis under euglycemic and diabetic conditions. This review focuses on the current understanding of carbon flux in gluconeogenesis, including substrate contribution of various gluconeogenic precursors to glucose production. Alterations of gluconeogenic metabolites and fluxes in T2DM are discussed. We also highlight ongoing knowledge gaps in the literature that require further investigation. A comprehensive analysis of gluconeogenesis may enable a better understanding of T2DM pathophysiology and identification of novel targets for treating hyperglycemia.

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.

Frequency of sarcopenia and associated outcomes in patients with chronic obstructive pulmonary disease

Background/aim

We aimed to evaluate the prevalence of sarcopenia and associated outcomes in patients with chronic obstructive pulmonary disease (COPD).

Materials and methods

This cross-sectional study was performed on 219 patients aged 50 years and over who were diagnosed with chronic obstructive pulmonary disease (COPD) according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines. The study included 196 (89.5%) male and 23 (10.5%) female patients. The mean age of the patients was 66.9 ± 10.1 years. To diagnose sarcopenia, muscle function was determined by a gait speed test. Muscle strength was assessed with a hand dynamometer and muscle mass was measured with a bioelectrical impedance analysis device. Pulmonary function tests and six-min walking tests were also performed. The modified Medical Research Council (mMRC) dyspnoea scale was used to evaluate all the participants. Our sample consisted of sarcopenic patients at different stages (17 presarcopenic patients (7.8%), 32 patients with sarcopenia (14.6%), 65 patients with severe sarcopenia (29.7%), and 105 nonsarcopenic patients (47.9%).

Results

Sarcopenia was significantly associated with age, BODE (body mass index (BMI), airflow obstruction, dyspnoea, and exercise capacity) index, GOLD spirometric classification, mMRC dyspnoea scale score, BMI, and educational status. Sarcopenia in COPD patients was firmly related to the severity of the disease and its prognosis. The prevalence of sarcopenia increased in severe and very severe COPD cases. The dyspnoea score was higher, and exercise capacities were lower in sarcopenic patients.

Conclusions

Sarcopenia in COPD patients was closely related to the severity of COPD and a negative prognosis. The frequency of sarcopenia increased in severe and very severe COPD cases. Dyspnoea scores were higher and exercise capacities were lower in patients with sarcopenia. In patients with COPD, a diagnosis of sarcopenia should be considered, and preventive measures should be taken before irreversible changes develop.

Prevalence of, and risk factors for underweight or excess weight in patients with chronic obstructive emphysema from a multiethnic region of Xinjiang, China

BACKGROUND

The purpose of this study is to assess the basic nutritional status (body metabolic index, BMI) and its risk factors in the patients suffering from chronic obstructive emphysema.

METHODS

We described their demographic characteristics and comorbidity distribution of 2812 obstructive emphysema participants. Comparative analyzes were conducted on BMI with different demographic characteristics and comorbidities status, and comprehensive analysis on risk factors of excess weight and underweight in patients with different characters.

RESULTS

The prevalence of underweight and excess weight was 17.57% and 31.54% respectively. There were differences in the distribution of three types of body mass index among patients with different demographic characteristics and different comorbidities. The study found that age of 50 ~ 64 (odds ratio, OR: 2.99), tuberculosis (OR: 2.41), and low TG (OR: 2.32) were the risk factors about underweight. Low HDL-C (OR: 4.15), nonalcoholic fatter liver (NAFLD) (OR: 3.96), and age of 50 ~ 64 (OR: 2.72) were closely related to the excess weight of participants.

CONCLUSIONS

This study highlighted the prevalence of underweight and excess weight in patients among emphysema. Comorbidities were important risk factors of underweight or excess weight among chronic emphysema patients. These findings were important for the prevention and treatment of chronic obstructive emphysema in the future.

Is peak expiratory flow an accurate sarcopenia screening tool in older patients referred to respiratory rehabilitation?

PURPOSE

To assess the performance of peak expiratory flow (PEF) for sarcopenia screening in patients with chronic obstructive pulmonary disease (COPD), using the revised European Working Group on Sarcopenia in Older People (EWGSOP-2) criteria as the reference standard in pulmonary rehabilitation patients; and second, to study the factors associated with low PEF in this population.

METHODS

Diagnostic accuracy study conducted in consecutive community-dwelling COPD rehabilitation patients. Sensitivity, specificity, accuracy, likelihood ratios, predictive values, and area under the Receiver-Operating Characteristic curve were retrospectively calculated for PEF (index test) and compared with EWGSOP-2 criteria (reference standard).

RESULTS

Of 151 potentially eligible patients, 79 (67.5 ± 7.1 years; 78.8% men) fulfilled inclusion criteria and 10 (12.7%) had a diagnosis of sarcopenia. The PEF cut-off with highest accuracy (65.8%) was PEF ≤ 200 L/min (sensitivity 90%, specificity 62.3%, and positive and negative likelihood ratios 2.39 and 0.16, respectively). Airway obstruction and muscle mass were significantly associated with PEF ≤ 200 L/min.

CONCLUSIONS

Considering the EWGSOP-2 criteria as the reference standard, a cut-off of PEF ≤ 200 L/min showed only fair validity for detecting sarcopenia, so it cannot be recommended as a stand-alone screening tool in older rehabilitation patients with COPD.

Diagnostic reference values for sarcopenia in Tibetans in China

Sarcopenia is an age-associated disease characterized by loss of muscle mass and function, but the diagnostic cutoff values remain controversial. To investigate the diagnostic cutoff values and incidence of sarcopenia in a plateau population, the limb skeletal muscle mass, gait speed and grip strength of 2318 Tibetan adults were measured according to the criteria of the Asian Working Group for Sarcopenia. We found that the diagnostic reference values for sarcopenia in the high-altitude population were significantly lower than those in the plain population, and the incidences of sarcopenia in the high-altitude population over 60 years old were 17.2% in men and 36.0% in women, which were significantly higher than those in the plain population. Our study proposes reference values for the diagnosis of sarcopenia in Tibet. We suggest that the cutoff value for sarcopenia in the plateau population should be established based on altitude. Hypoxia may be an important risk factor for sarcopenia.

Low skeletal muscle area as a prognostic marker for chronic obstructive pulmonary disease in elderly patients admitted to ICU

Low L3 skeletal muscle area (SMA), which is assessed on computed tomography (CT) images, has been reported to indicate poor clinical outcomes of patients with acute exacerbation of chronic obstructive pulmonary disease (COPD). The dorsal muscle group area at the T12 vertebral level (T12DMA) was used as an alternative to L3 SMA. This study aimed to investigate whether T12DMA could be used as a predictor of in-hospital mortality and long-term survival in elderly patients with COPD admitted to the intensive care unit (ICU). This single-center retrospective case-control study was performed by analyzing the clinical information and measuring T12DMA on chest CT images of elderly patients with COPD admitted to the ICU between May 2013 and May 2018. This study included 136 patients. The multivariate logistic regression analysis showed that T12DMA, neutrophil-lymphocyte ratio, invasive mechanical ventilation, and systemic steroid therapy were independent risk factors for predicting the hospital mortality. The median survival was significantly higher in the high-T12DMA group (214 days) than in the low-T12DMA group (32 days).

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

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.

Clinical Value of Muscle Mass Assessment in Clinical Conditions Associated with Malnutrition

Malnutrition results from a reduction of food intake or an alteration of nutrient assimilation and leads to decreased lean mass. Strong evidence shows that malnutrition associated with loss of muscle mass negatively impacts clinical outcomes. The preservation or improvement of muscle mass represents a challenge. This review aims to (1) describe current methods to assess muscle mass in clinical practice, (2) describe the associations between muscle mass and clinical outcomes, and (3) describe the impact of interventions aiming at increasing muscle mass on clinical outcomes. It highlights the importance of assessing muscle mass as part of the screening and the follow-up of malnutrition in clinical practice.

MECHANISMS OF ENDOCRINE DISEASE: Sarcopenia in endocrine and non-endocrine disorders

Objective This paper reviews the main mechanisms, diagnostic criteria, treatment options and available data on sarcopenia in endocrine and non-endocrine disorders. The literature notes the presence of sarcopenia as a comorbid condition or a complication of another clinical situation and not a disease that only affects elderly patients. Method We performed a literature review, focusing on the following: mechanisms related to sarcopenia in elderly patients, and sarcopenia as it presents in the context of chronic and endocrine diseases; diagnostic tools and methods; aspects of sarcopenia and treatment options specific to chronic diseases and endocrine disorders respectively. Results Sarcopenia in chronic and endocrine disorders shares many mechanisms with sarcopenia affecting elderly patients, but certain diseases can have a predominant aspect that leads to sarcopenia. The prevalence of sarcopenia varies, depending on different diagnostic criteria, from around 12 to 60% in chronic illnesses and 15 to 90% in endocrine disorders. The interplay between sarcopenia, chronic diseases and elderly patients requires further study, to clarify the impact of each, in terms of prognosis and mortality. Conclusion Awareness of the presentation of sarcopenia in the context of other diseases and ages (and not just the elderly) is fundamental to ensure that preventive measures can be deployed.

Frailty trajectories in adult lung transplantation: A cohort study

BACKGROUND

Frailty is common in adults with advanced lung disease and is associated with death before and after lung transplantation. We aimed to determine whether frailty changes from before to after the lung transplant.

METHODS

In a single-center, prospective cohort study among adults undergoing lung transplantation from 2010 to 2017, we assessed frailty by the Short Physical Performance Battery (SPPB; higher scores reflect less frailty) and Fried Frailty Phenotype (FFP; higher scores reflect greater frailty) before and repeatedly up to 36 months after transplant. We tested for changes in frailty scores over time using segmented mixed effects models, adjusting for age, sex, and diagnosis. We quantified the proportion of subjects transitioning between frailty states (frail vs not frail) from before to after the transplant.

RESULTS

In 246 subjects, changes in frailty occurred within the first 6 post-operative months and remained stable thereafter. The overall change in frailty was attributable to improvements among those subjects who were frail before transplant. They experienced a 5.1-point improvement in SPPB (95% confidence interval [CI] 4.6-5.7) and a 1.8-point improvement in FFP (95% CI -2.1 to -1.6) during the early period. Frailty by SPPB and FFP did not change in those who were not frail before transplant. Approximately 84% of survivors who were frail before transplant became not frail after transplant.

CONCLUSIONS

Pre-operative frailty resolves in many patients after lung transplantation. Because a large proportion of frailty may be attributable to advanced lung disease, frailty alone should not be an absolute contraindication to transplantation.

The Ratio Serum Creatinine/Serum Cystatin C (a Surrogate Marker of Muscle Mass) as a Predictor of Hospitalization in Chronic Obstructive Pulmonary Disease Outpatients

BACKGROUND

In chronic obstructive pulmonary disease (COPD), low muscle mass has been associated with several clinical outcomes such as low exercise capacity, hospital admission, and mortality. The Sarcopenia Index (SI) is a novel way to estimate muscle mass based on the ratio of serum creatinine (produced exclusively by muscle)/cystatin C (produced by all nucleated body cells).

OBJECTIVES

This study aims to assess the SI in stable COPD outpatients, as compared with a healthy control group, to quantify its relationship with several important clinical features in COPD, and to study its potential usefulness to predict COPD exacerbations and hospital admissions.

METHODS

The SI was calculated in 18 healthy control subjects and 65 stable COPD outpatients were included in the study. Patients were prospectively followed for 1 year after being enrolled in the study.

RESULTS

COPD patients had a lower SI than controls, that is lower muscle mass. Furthermore, patients with a modified Medical Research Council dyspnea score ≥2, patients with a COPD Assessment Test score ≥10, and patients with a high risk of exacerbation had lower levels of SI compared with patients without these characteristics. SI correlated with FEV1 (r = 0.491, p < 0.001), the 6-min walking test (r = 0.560, p = 0.001), and the Fat-Free Mass Index (r = 0.431, p = 0.017). Univariate and multivariate Cox proportional risk analysis showed that a low SI is an independent predictor of hospital admission in COPD outpatients followed for 1 year (HR 5.16, p = 0.025).

CONCLUSIONS

The ratio serum creatinine/serum cystatin C correlates with several COPD characteristics, and it can be used to predict COPD hospitalization.