Prevalence and characteristics of nutritional depletion in patients with stable COPD eligible for pulmonary rehabilitation

Abdominal obesity, sarcopenia, and osteoporosis are associated with frailty in men living with and without HIV

OBJECTIVE

The relationships between frailty and body composition in older adults with HIV infection are poorly understood. We sought to describe associations between frailty and measures of body composition among adult men with HIV and without HIV.

DESIGN/METHODS

Men with and without HIV (age 50-69 years) in the Multicenter AIDS Cohort Study (MACS) Bone Strength Substudy were included if evaluated for frailty (by Fried phenotype) and body composition [BMI, waist circumference, abdominal visceral (VAT) and subcutaneous (SAT) adipose tissue, sarcopenia, and osteopenia/osteoporosis]. All participants with HIV infection were on antiretroviral therapy. Multivariate multinomial logistic regression models were used to determine associations of frailty with body composition.

RESULTS

A total of 399 men, including 199 men with HIV and 200 men without HIV, both with median age 60 years, constituted our study population. Frailty prevalence was 16% (men with HIV) vs. 8% (men without HIV). HIV serostatus was associated with a 2.43 times higher odds of frailty (P = 0.01). Higher waist circumference, VAT, sarcopenia, and femoral neck osteoporosis were associated with increased odds of frailty (aOR 4.18, 4.45, 4.15, and 13.6, respectively, and all P < 0.05); BMI and SAT were not. None of these measures presented a differential association with frailty by HIV serostatus (all P > 0.20).

CONCLUSION

Higher abdominal obesity and sarcopenia were associated with frailty among men with and without HIV. Assessment of these body composition parameters may help detect frailty in the clinical setting.

Effects of aging and comorbidities on nutritional status and muscle dysfunction in patients with COPD

Chronic obstructive pulmonary disease (COPD) is a prevalent, complex and debilitating disease which imposes a formidable burden on patients and the healthcare system. The recognition that COPD is a multifaceted disease is not new, and increasing evidence have outlined the importance of its extra-pulmonary manifestations and its relation to other comorbid conditions in the clinical course of the disease and its societal cost. The relationship between aging, COPD and its comorbidities on skeletal muscle function and nutritional status is complex, multidirectional and incompletely understood. Despite this, the current body of knowledge allows the identification of various, seemingly partially independent factors related both to the normal aging process and to the independent deleterious effects of chronic diseases on muscle function and body composition. There is a dire need of studies evaluating the relative contribution of each of these factors, and their potential synergistic effects in patients with COPD and advanced age/comorbid conditions, in order to delineate the best course of therapeutic action in this increasingly prevalent population.

Can muscle protein metabolism be specifically targeted by nutritional support and exercise training in chronic obstructive pulmonary disease?

Chronic obstructive pulmonary disease (COPD) associates with several extra-pulmonary effects. Muscle dysfunction and wasting is one of the most prominent extra-pulmonary effects and contributes to exercise limitation and health related quality of life (HRQoL), morbidity as well as mortality. The loss of muscle mass is characterised by an impaired balance between protein synthesis (anabolism) and protein breakdown (catabolism) which relates to nutritional disturbances, muscle disuse and the presence of a systemic inflammation, among other factors. Current approaches to reverse skeletal muscle dysfunction and wasting attain only modest improvements. The development of new therapeutic strategies aiming at improving skeletal muscle dysfunction and wasting are needed. This requires a better understanding of the underlying molecular pathways responsible for these abnormalities. In this review we update recent research on protein metabolism, nutritional depletion as well as physical (in)activity in relation to muscle wasting and dysfunction in patients with COPD. We also discuss the role of nutritional supplementation and exercise training as strategies to re-establish the disrupted balance of protein metabolism in the muscle of patients with COPD. Future areas of research and clinical practice directions are also addressed.

Joint statement for the diagnosis, management, and prevention of chronic obstructive pulmonary disease for Gulf Cooperation Council countries and Middle East-North Africa region, 2017

Smoking and subsequent development of COPD is an ever-increasing epidemic in Arabian Gulf and Middle East countries, with no signs of decline. The important fact to be highlighted is that this COPD epidemic of increasing incidence and prevalence is mostly unrecognized by patients, due to the common attribution of symptoms to "smoker's cough", and the underdiagnosis and undertreatment by physicians because the common signs and symptoms masquerade as asthma. Consequently, there are long-term adverse effects of missing the diagnosis. The purpose of this review article is to focus upon the status of COPD in Arabian Gulf and Middle East countries, stressing the increasing burden of smoking and COPD, to emphasize the specific factors leading to rise in prevalence of COPD, to bring to light the underdiagnosis and undermanagement of COPD, and to treat COPD in conformity with standard guidelines with local and regional modifications. This review ends with suggestions and recommendations to the health department to formulate policies and to generate awareness among the general public about the side effects of smoking and consequences of COPD.

The Influence of Body Composition on Pulmonary Rehabilitation Outcomes in Chronic Obstructive Pulmonary Disease Patients

INTRODUCTION

Alterations in body composition are commonly present in chronic obstructive pulmonary disease (COPD). The hypothesis of this study is that COPD patients would achieve clinical benefits after pulmonary rehabilitation (PR) independent of muscle mass depletion or body weight.

METHODS

We conducted a retrospective cohort study using single-frequency bioelectrical impedance analysis (BIA) for assessment of fat-free mass (FFM) depletion (muscle depletion). Patients were stratified into three categories based on (1) obesity BMI ≥ 30 kg/m², (2) non-obesity BMI < 30 kg/m², and (3) combined cachexia (BMI < 21 kg/m² and FFM index < 16 kg/m²) and muscle atrophy (BMI ≥ 21 kg/m² and FFMI < 16 kg/m²). PR outcomes were defined as the improvement in exercise capacity (maximal exercise capacity, 6-min walk, constant workload cycle exercise duration) and quality of life determined by Chronic Respiratory Questionnaire after PR.

RESULTS

We studied 72 patients with available FFM measured by BIA. Patients were predominantly elderly man (N = 71; 98%), with a mean age of 72 years with COPD GOLD stage I-IV. The groups were balanced in terms of age, comorbidities, baseline FEV1, exercise capacity, and quality of life. The absolute changes in patients with muscle depletion or obesity compared to those without muscle depletion or obesity were not statistically different as was the percentage of patients reaching the minimal clinically important difference (MCID) after PR.

CONCLUSION

A comprehensive PR program in COPD patients improved exercise tolerance and quality of life independent of muscle mass depletion or obesity. Similarly, muscle depletion or obesity had no effect on the percentage of patients achieving the MCID for measures of quality of life and exercise tolerance after PR.

Mice overexpressing growth hormone exhibit increased skeletal muscle myostatin and MuRF1 with attenuation of muscle mass

Background

In contrast to the acute effects of growth hormone (GH) on skeletal muscle protein synthesis, long-term GH treatment appears to have negligible effects on muscle mass. Despite this knowledge, little is known regarding the chronic effects of GH on skeletal muscle protein synthesis and atrophy signaling pathways. The purpose of this study was to determine if protein synthesis pathways are attenuated and/or muscle atrophy intracellular signaling pathways are altered in the skeletal muscle of transgenic bovine GH (bGH) mice.

Methods

The gastrocnemius and soleus from 5-month-old male bGH mice (n = 9) and wild type (WT) controls (n = 9) were harvested and analyzed for proteins involved in the protein synthesis (Akt/mTOR), growth and proliferation (MAPK), and muscle atrophy (MuRF1 and myostatin) pathways.

Results

Total body mass was significantly increased in bGH mice compared to WT controls (49%, P < 0.0001). When expressed relative to total body mass, the gastrocnemius (− 28%, P < 0.0001), but not the soleus, was significantly lower in mice overexpressing GH, compared to controls. Transgenic bGH mice had elevated phosphorylation levels of protein kinase b (Akt1), 4E-binding protein 1 (4E-BP1), p70 S6 kinase, p42/44, and p38 (P < 0.05) compared to WT littermates. Mature myostatin (26 kDa), premature myostatin (52 kDa), and activin receptor type IIB (AcvR2B) protein levels were increased in bGH mice (P < 0.05), along with elevated phosphorylation levels of mothers against decapentaplegic homolog (Smad2) (59%, P < 0.0001). Mice overexpressing GH had increased MuRF1 expression (30%, P < 0.05) and insulin receptor substrate 1 (IRS1) serine phosphorylation (44%, P < 0.05) in the gastrocnemius, but not the soleus, when compared to controls.

Conclusions

These findings demonstrate that chronic elevations in circulating GH have a critical impact on signaling pathways involved in skeletal muscle protein synthesis and atrophy, and suggest that MuRF1, myostatin, and IRS1 serine phosphorylation may act to inhibit exaggerated glycolytic muscle growth, in environments of chronic GH/IGF-1 excess.

Fat-free mass depletion in patients with COPD in Brazil: development of a new cutoff point and its relation with mortality and extrapulmonary manifestations

BACKGROUND/OBJECTIVES

None of the cutoff points for fat-free mass index (FFMI) were tested for the Brazilian population, and it is unknown whether the available ones are able to discriminate extrapulmonary disease manifestations. This cross-sectional study aims to develop and validate a cutoff point for FFM depletion based on Brazilian patients with chronic obstructive pulmonary disease (COPD) and to verify its association and of previously published cutoffs with extrapulmonary manifestations.

SUBJECTS/METHODS

A new cutoff point was obtained from the best FFMI value for discrimination of preserved exercise capacity in a sample of patients (n=57). The discriminative capacity was assessed in another sample (n=96). The new cutoff point and other previously published ones were tested to discriminate low exercise capacity, physical inactivity, sedentary lifestyle and low quality of life. A receiver operation characteristics curve with area under the curve (AUC) value was plotted and each cutoff points' discriminative capacity was calculated. Cox regression and Kaplan-Meier method assessed the association between the cutoff points and mortality.

RESULTS

The new cutoff points for FFMI were 14.65 kg/m² for women (AUC=0.744; sensitivity (Se)=0.88; specificity (Sp)=0.60) and 20.35 kg/m² for men (AUC=0.565; Se=0.36; Sp=0.81). The new cutoffs were the best to discriminate poor exercise capacity assessed by walked distance in % predicted and quality of life. Only the new cutoff point was associated with mortality (HR=2.123; 95% CI: 1.03-4.33, P=0.039, log rank P=0.035).

CONCLUSIONS

Only the new cutoff point was associated with all-cause mortality, and it had the highest discriminating capacity for exercise capacity and quality of life in Brazilian patients with COPD.

Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Lung Disease 2017 Report. GOLD Executive Summary

This Executive Summary of the Global Strategy for the Diagnosis, Management, and Prevention of COPD, Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2017 report focuses primarily on the revised and novel parts of the document. The most significant changes include: (1) the assessment of chronic obstructive pulmonary disease has been refined to separate the spirometric assessment from symptom evaluation. ABCD groups are now proposed to be derived exclusively from patient symptoms and their history of exacerbations; (2) for each of the groups A to D, escalation strategies for pharmacologic treatments are proposed; (3) the concept of deescalation of therapy is introduced in the treatment assessment scheme; (4) nonpharmacologic therapies are comprehensively presented; and (5) the importance of comorbid conditions in managing chronic obstructive pulmonary disease is reviewed.

Thoracic muscle cross-sectional area is associated with hospital length of stay post lung transplantation: a retrospective cohort study

Low muscle mass is common in lung transplant (LTx) candidates; however, the clinical implications have not been well described. The study aims were to compare skeletal muscle mass in LTx candidates with controls using thoracic muscle cross-sectional area (CSA) from computed tomography and assess the association with pre- and post-transplant clinical outcomes. This was a retrospective, single-center cohort study of 527 LTx candidates [median age: 55 IQR (42-62) years; 54% male]. Thoracic muscle CSA was compared to an age- and sex-matched control group. Associations between muscle CSA and pre-transplant six-minute walk distance (6MWD), health-related quality of life (HRQL), delisting/mortality, and post-transplant hospital outcomes and one-year mortality were evaluated using multivariable regression analysis. Muscle CSA for LTx candidates was about 10% lower than controls (n = 38). Muscle CSA was associated with pre-transplant 6MWD, but not HRQL, delisting or pre- or post-transplant mortality. Muscle CSA (per 10 cm² difference) was associated with shorter hospital stay [0.7 median days 95% CI (0.2-1.3)], independent of 6MWD. In conclusion, thoracic muscle CSA is a simple, readily available estimate of skeletal muscle mass predictive of hospital length of stay, but further study is needed to evaluate the relative contribution of muscle mass versus functional deficits in LTx candidates.

2D-DIGE proteomic analysis of vastus lateralis from COPD patients with low and normal fat free mass index and healthy controls

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is associated with several extra-pulmonary effects of which skeletal muscle wasting is one of the most common and contributes to reduced quality of life, increased morbidity and mortality. The molecular mechanisms leading to muscle wasting are not fully understood. Proteomic analysis of human skeletal muscle is a useful approach for gaining insight into the molecular basis for normal and pathophysiological conditions.

METHODS

To identify proteins involved in the process of muscle wasting in COPD, we searched differentially expressed proteins in the vastus lateralis of COPD patients with low fat free mass index (FFMI), as a surrogate of muscle mass (COPDL, n = 10) (FEV1 33 ± 4.3% predicted, FFMI 15 ± 0.2 Kg.m-2), in comparison to patients with COPD and normal FFMI (COPDN, n = 8) and a group of age, smoking history, and sex matched healthy controls (C, n = 9) using two-dimensional fluorescence difference in gel electrophoresis (2D-DIGE) technology, combined with mass spectrometry (MS). The effect of silencing DOT1L protein expression on markers of cell arrest was analyzed in skeletal muscle satellite cells (HSkMSCs) in vitro and assessed by qPCR and Western blotting.

RESULTS

A subset of 7 proteins was differentially expressed in COPDL compared to both COPDN and C. We found an increased expression of proteins associated with muscle homeostasis and protection against oxidative stress, and a decreased expression of structural muscle proteins and proteins involved in myofibrillogenesis, cell proliferation, cell cycle arrest and energy production. Among these was a decreased expression of the histone methyltransferase DOT1L. In addition, silencing of the DOT1L gene in human skeletal muscle satellite cells in vitro was significantly related to up regulation of p21 WAF1/Cip1/CDKN1A, a marker of cell arrest and ageing.

CONCLUSIONS

2D-DIGE coupled with MS identified differences in the expression of several proteins in the wasted vastus lateralis that are relevant to the disease process. Down regulation of DOT1L in the vastus lateralis of COPDL patients may mediate the muscle wasting process through up regulation of markers of cell arrest and senescence.

Global Strategy for the Diagnosis, Management and Prevention of Chronic Obstructive Lung Disease 2017 Report: GOLD Executive Summary

This Executive Summary of the Global Strategy for the Diagnosis, Management and Prevention of COPD, Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2017 Report focuses primarily on the revised and novel parts of the document. The most significant changes include: (i) the assessment of chronic obstructive pulmonary disease has been refined to separate the spirometric assessment from symptom evaluation. ABCD groups are now proposed to be derived exclusively from patient symptoms and their history of exacerbations; (ii) for each of the groups A to D, escalation strategies for pharmacological treatments are proposed; (iii) the concept of de-escalation of therapy is introduced in the treatment assessment scheme; (iv)non-pharmacological therapies are comprehensively presented and (v) the importance of co-morbid conditions in managing COPD is reviewed.

Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Lung Disease 2017 Report: GOLD Executive Summary

This Executive Summary of the Global Strategy for the Diagnosis, Management, and Prevention of COPD (GOLD) 2017 Report focuses primarily on the revised and novel parts of the document. The most significant changes include: 1) the assessment of COPD has been refined to separate the spirometric assessment from symptom evaluation. ABCD groups are now proposed to be derived exclusively from patient symptoms and their history of exacerbations; 2) for each of the groups A to D, escalation strategies for pharmacological treatments are proposed; 3) the concept of de-escalation of therapy is introduced in the treatment assessment scheme; 4) nonpharmacologic therapies are comprehensively presented and; 5) the importance of comorbid conditions in managing COPD is reviewed.

Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Lung Disease 2017 Report: GOLD Executive Summary

This Executive Summary of the Global Strategy for the Diagnosis, Management, and Prevention of COPD (GOLD) 2017 Report focuses primarily on the revised and novel parts of the document. The most significant changes include: 1) the assessment of chronic obstructive pulmonary disease has been refined to separate the spirometric assessment from symptom evaluation. ABCD groups are now proposed to be derived exclusively from patient symptoms and their history of exacerbations; 2) for each of the groups A to D, escalation strategies for pharmacological treatments are proposed; 3) the concept of de-escalation of therapy is introduced in the treatment assessment scheme; 4) nonpharmacologic therapies are comprehensively presented and; 5) the importance of comorbid conditions in managing COPD is reviewed.

Sarcopenia correlates with systemic inflammation in COPD

Background

Muscle wasting and chronic inflammation are predominant features of patients with COPD. Systemic inflammation is associated with an accelerated decline in lung function. In this study, the prevalence of sarcopenia and the relationships between sarcopenia and systemic inflammations in patients with stable COPD were investigated.

Materials and methods

In a cross-sectional design, muscle strength and muscle mass were measured by handgrip strength (HGS) and bioelectrical impedance analysis in 80 patients with stable COPD. Patients (≥40 years old) diagnosed with COPD were recruited from outpatient clinics, and then COPD stages were classified. Sarcopenia was defined as the presence of both low muscle strength (by HGS) and low muscle mass (skeletal muscle mass index [SMMI]). Levels of circulating inflammatory biomarkers (IL-6 and high-sensitivity TNFα [hsTNFα]) were measured.

Results

Sarcopenia was prevalent in 20 (25%) patients. Patients with sarcopenia were older, had lower body mass index, and a higher percentage of cardiovascular diseases. In addition, they had significantly higher modified Medical Research Council scores and lower 6-minute walk distance than those without sarcopenia. HGS was significantly correlated with age, modified Medical Research Council score, and COPD Assessment Test scores. Both HGS and SMMI had associations with IL-6 and hsTNFα (HGS, r=−0.35, P=0.002; SMMI, r=−0.246, P=0.044) level. In multivariate analysis, old age, lower body mass index, presence of cardiovascular comorbidities, and higher hsTNFα levels were significant determinants for sarcopenia in patients with stable COPD.

Conclusion

Sarcopenia is very common in patients with stable COPD, and is associated with more severe dyspnea-scale scores and lower exercise tolerance. Systemic inflammation could be an important contributor to sarcopenia in the stable COPD population.

Vitamin D deficiency: What does it mean for chronic obstructive pulmonary disease (COPD)? a compherensive review for pulmonologists

OBJECTIVES

Vitamin D deficiency and Chronic Obstructive Pulmonary Disease (COPD) are both under-recognized health problems, world-wide. Although Vitamin D has long been known for calcemic effects it also has less known noncalcemic effects. Recent data have shown that Vitamin D deficiency is highly prevalent in patients with COPD and correlates with forced expiratory volume in one second (FEV₁ ) and FEV₁ decline. The objective of this work was to review the current literature on vitamin D deficiency in relation with COPD.

DATA SOURCE

A literature search, using the words "vitamin D" and "COPD", was undertaken in Pubmed database.

RESULTS

The noncalcemic effects of vitamin D relating with COPD may be summarised as increasing antimicrobial peptide production, regulation of inflammatory response and airway remodelling. Vitamin D inhibits the production of several proinflammatory cytokines and leads to suppression Th1 and Th17 responses which may be involved in the pathogenesis of COPD. Vitamin D insufficiency may also contribute to chronic respiratory infections and airway colonization so returning vitamin D concentrations to an optimal range in patients with COPD might reduce bacterial load and concomitant exacerbations.Vitamin D is also important for COPD-related comorbodities such as osteoporosis, muscle weakness and cardiovascular diseases. Data about the effect of Vitamin D supplementation on those comorbidities in relation with COPD are been scarce.

CONCLUSION

Improving the blood level of Vitamin D into the desired range may have a beneficial effect bones and muscles, but more studies are needed to test to test that hypothesis.

Two-year mortality in survivors of acute exacerbations of chronic obstructive pulmonary disease: A North Indian study

OBJECTIVES

Data about long-term mortality of Indian patients following acute exacerbation of chronic obstructive pulmonary disease (AECOPD) are scant. We set out to study the 2-year mortality in north Indian patients following discharge after AECOPD.

MATERIALS AND METHODS

One hundred and fifty-one (96 male) patients admitted for AECOPD and discharged were followed for 2 years at 3, 6, 12, 18, and 24 months for mortality. Statistical analysis was performed to identify risk factors associated with mortality.

RESULTS

Sixty (39.7%) of the 151 recruited died during the 24 months of follow-up, 30 (19.8%) at 3-month, 43 (28.5%) at 6-month, 49 (32.4%) at 1-year, 55 (36.4%) at 18-month, and 60 (39.7%) at 2 years. There was no mortality in Global Initiative for Chronic Obstructive Lung Disease (GOLD) Stage I (0 of 6 cases), whereas it was 12.3% (n = 8 of 65 patients) in GOLD Stage II, 41.7% (n = 15 of 36 cases), in GOLD Stage III, and 84.1% (n = 37 of 4 cases), of patients with GOLD Stage IV. Mortality was associated with 6-min walk distance, oxygen saturation, low body mass index, history of congestive heart failure, and St. George Respiratory Questionnaire score.

CONCLUSION

Indian patients discharged after AECOPD have a high 2-year mortality. Measures to reduce the frequency of exacerbations need to be routinely adopted in patients with COPD.

Quantitative Assessment of Erector Spinae Muscles in Patients with Chronic Obstructive Pulmonary Disease. Novel Chest Computed Tomography-derived Index for Prognosis

RATIONALE

Loss of skeletal muscle mass and physical inactivity are important manifestations of chronic obstructive pulmonary disease (COPD), and both are closely related to poor prognoses in patients with COPD. Antigravity muscles are involved in maintaining normal posture and are prone to atrophy with inactivity. The erector spinae muscles (ESM) are one of the antigravity muscle groups, and they can be assessed by chest computed tomography (CT).

OBJECTIVES

We hypothesized that the cross-sectional area of ESM (ESMCSA) visualized on chest CT images may serve as a predictor of mortality in patients with COPD.

METHODS

This study was part of the prospective observational study undertaken at Kyoto University Hospital. ESMCSA was measured on a single-slice axial CT image at the level of the 12th thoracic vertebra in patients with COPD. The cross-sectional area of the pectoralis muscles (PMCSA) was also measured. We evaluated the relationship between ESMCSA and clinical parameters, including mortality, in patients with COPD. Age- and height-matched smoking control subjects were also evaluated.

MEASUREMENTS AND MAIN RESULTS

In total, 130 male patients and 20 smoking control males were enrolled in this study. ESMCSA was significantly lower in patients with COPD than in the smoking control subjects and was significantly correlated with disease severity. There was a significant but only moderate correlation between ESMCSA and PMCSA. ESMCSA was significantly correlated with previously reported prognostic factors, such as body mass index, dyspnea (modified Medical Research Council dyspnea scale score), FEV1 percent predicted value, inspiratory capacity to total lung capacity ratio, and emphysema severity (percentage of the lung field occupied by low attenuation area). Compared with PMCSA, ESMCSA was more strongly associated with mortality in patients with COPD. Stepwise multivariate Cox proportional hazards analysis revealed that, among these known prognostic factors, ESMCSA was the strongest risk factor for mortality (hazard ratio, 0.85; 95% confidence interval, 0.79-0.92; P < 0.001) and mMRC dyspnea scale score was an additional factor (hazard ratio, 2.35; 95% confidence interval, 1.51-3.65; P < 0.001).

CONCLUSIONS

ESMCSA assessed by chest CT may be a valuable clinical parameter, as ESACSA correlates significantly with physiological parameters, symptoms, and disease prognosis.

The Effect of Fatigue and Fatigue Intensity on Exercise Tolerance in Moderate COPD

INTRODUCTION

Fatigue is one of the most disabling symptoms in COPD, but little is known about the impact of fatigue on functional disability. We explored the impact of fatigue and fatigue intensity on exercise tolerance after adjusting for other factors using multivariate analysis and compared it to that of dyspnoea.

METHODS

A total of 119 patients with mainly moderate-severe stable COPD (38 % women, mean age 66 years) were enrolled. We used the Medical Research Council dyspnoea scores (MRC), Manchester COPD fatigue scale (MCFS) and its three dimensions, Borg scales for fatigue and dyspnoea, six-minute walk distance (6MWD), St George's Respiratory Questionnaire, the BODE index, and the Centre for Epidemiological Study on Depression scale (CES-D), and we measured spirometry, blood gases, systemic inflammatory markers and fat-free mass index (FFMI).

RESULTS

Fatigue measured using the MCFS was associated with 6MWD and explained 22 % of the variability in 6MWD (p < 0.001). Fatigue remained associated with 6MWD after adjusting for MRC dyspnoea, FFMI and FEV1, FVC, PaO2, PaCO2, CES-D, TNF-alpha, smoking status, age and gender. We found that 33, 50 and 23 % of patients reported an increase by 2 scores on Borg scales for fatigue, dyspnoea or both at the end of the 6MWT. Fatigue scores (both before and after the 6MWT) were negatively correlated with 6MWD after adjusting for FEV1, FFMI, CES-D score and age (p = 0.007 and 0.001, respectively).

CONCLUSION

In moderate stable COPD, fatigue may be a central driver of functional disability, to the same extent as dyspnoea.

Microvascular oxygen extraction during maximal isometric contraction in patients with chronic obstructive pulmonary disease

Abstract Introduction: COPD presents decrease in oxidative metabolism with possible losses of cardiovascular adjustments, suggesting slow kinetics microvascular oxygen during intense exercise. Objective: To test the hypothesis that chronic obstructive pulmonary disease (COPD) patients have lower muscle performance in physical exercise not dependent on central factors, but also greater muscle oxygen extraction, regardless of muscle mass. Methods: Cross-sectional study with 11 COPD patients and nine healthy subjects, male, paired for age. Spirometry and body composition by DEXA were evaluated. Muscular performance was assessed by maximal voluntary isometric contraction (MVIC) in isokinetic dynamometer and muscle oxygen extraction by the NIRS technique. Student t-test and Pearson correlation were applied. A significance level of p<0.05 was adopted. Results: Patients had moderate to severe COPD (FEV1 = 44.5 ± 9.6% predicted; SpO2 = 94.6 ± 1.6%). Lean leg mass was 8.3 ± 0.9 vs. 8.9 ± 1.0 kg (p =0.033), when comparing COPD and control patients, respectively. The decreased muscle oxygen saturation corrected by muscle mass was 53.2% higher (p=0.044) in the COPD group in MVIC-1 and 149.6% higher (p=0.006) in the MVIC-2. Microvascular extraction rate of oxygen corrected by muscle mass and total work was found to be 114.5% higher (p=0.043) in the COPD group in MVIC-1 and 210.5% higher (p=0.015) in the MVIC-2. Conclusion: COPD patients have low muscle performance and high oxygen extraction per muscle mass unit and per unit of work. The high oxygen extraction suggests that quantitative and qualitative mechanisms can be determinants of muscle performance in patients with COPD.

Adaptations in limb muscle function following pulmonary rehabilitation in patients with COPD - a review

Even though chronic obstructive pulmonary disease (COPD) is primarily a disease of the respiratory system, limb muscle dysfunction characterized by muscle weakness, reduced muscle endurance and higher muscle fatigability, is a common secondary consequence and a major systemic manifestation of the disease. Muscle dysfunction is especially relevant in COPD because it is related to important clinical outcomes such as mortality, quality of life and exercise intolerance, independently of lung function impairment. Thus, improving muscle function is considered an important therapeutic goal in COPD management. Pulmonary rehabilitation (PR) is a multidisciplinary, evidence-based and comprehensive approach used to promote better self-management of the disease, minimize symptom burden, optimize functional status, and increase participation in activities of daily life. Exercise training, including cardiovascular and muscle exercises, is the cornerstone of PR and is considered the best available strategy to improve exercise tolerance and muscle function among patients with COPD. This paper addresses the various components of exercise training within PR used to improve limb muscle function in COPD, providing clinicians and health-care professionals with an overview and description of these various exercise modalities and of their effects on limb muscle function. Guidance and recommendations to help design optimal limb muscle training regimens for these patients are also presented.

The association between vitamin D and COPD risk, severity, and exacerbation: an updated systematic review and meta-analysis

Background

In recent years, the pleiotropic roles of vitamin D have been highlighted in various diseases. However, the association between serum vitamin D and COPD is not well studied. This updated systematic review and meta-analysis aimed to assess the relationship between vitamin D and the risk, severity, and exacerbation of COPD.

Methods

A systematic literature search was conducted in PubMed, Medline, EMBASE, Chinese National Knowledge Infrastructure, Wanfang, and Weipu databases. The pooled risk estimates were standardized mean difference (SMD) with 95% confidence interval (CI) for vitamin D levels and odds ratio (OR) with 95% CI for vitamin D deficiency. Meta-regression and subgroup analyses were performed on latitude, body mass index, and assay method.

Results

A total of 21 studies, including 4,818 COPD patients and 7,175 controls, were included. Meta-analysis showed that lower serum vitamin D levels were found in COPD patients than in controls (SMD: −0.69, 95% CI: −1.00, −0.38, P<0.001), especially in severe COPD (SMD: −0.87, 95% CI: −1.51, −0.22, P=0.001) and COPD exacerbation (SMD: −0.43, 95% CI: −0.70, −0.15, P=0.002). Vitamin D deficiency was associated with increased risk of COPD (OR: 1.77, 95% CI: 1.18, 2.64, P=0.006) and with COPD severity (OR: 2.83, 95% CI: 2.00, 4.00, P<0.001) but not with COPD exacerbation (OR: 1.17, 95% CI: 0.86, 1.59, P=0.326). Assay methods had significant influence on the heterogeneity of vitamin D deficiency and COPD risk.

Conclusion

Serum vitamin D levels were inversely associated with COPD risk, severity, and exacerbation. Vitamin D deficiency is associated with increased risk of COPD and severe COPD but not with COPD exacerbation. It is worth considering assay methods in the heterogeneity sources analysis of association between vitamin D deficiency and COPD.

Preliminary study on the assessment of visceral adipose tissue using dual-energy x-ray absorptiometry in chronic obstructive pulmonary disease

Background

Visceral adipose tissue (VAT) was shown to be increased in patients with chronic obstructive pulmonary disease (COPD) compared to control subjects with comparable body mass index (BMI). Our aim was to determine the relation of VAT by dual-energy x-ray absorptiometry (DEXA) in patients with COPD by disease severity, BMI, other indices of body composition and static lung volumes.

Methods

294 COPD patients admitted for rehabilitation were studied. Lung function, static lung volumes and body composition (i.e. BMI, waist circumference, fat-free mass, fat mass and fat distribution between android and gynoid fat mass) were assessed before entering pulmonary rehabilitation. VAT was estimated within the android region by using DEXA. Patients were stratified for gender, BMI (cut-off of 25 kg/m²) and GOLD stage. To assess the impact of VAT on lung volumes, patients were also stratified for VAT less and above 50^th percentile.

Results

Both male and female patients with more severe airflow limitation had significantly lower VAT values, but these differences disappeared after stratification for BMI. VAT was significantly and strongly correlated with other body composition parameters (all p < 0.001). Patients with moderate to severe airflow limitation and lower VAT had increased static lung hyperinflation and lower diffusing capacity for carbon monoxide. Nevertheless, multivariate stepwise regression models including for BMI, age, gender and forced expiratory volume in 1 s (FEV₁) as confounders did not confirm an independent role for VAT on static lung hyperinflation and diffusion capacity.

Conclusion

After stratification for BMI, VAT is comparable in moderate to very severe COPD patients. Furthermore, BMI and demographics, but not VAT, were independent predictors of static lung hyperinflation and diffusing capacity in COPD.

Prevalence of undiagnosed airflow obstruction among people with a history of smoking in a primary care setting

Purpose

The purpose of this study was to define the prevalence of undiagnosed airflow obstruction (AO) among subjects with a history of smoking but no previous diagnosis of chronic lung disease. The finding of AO likely represents diagnosis of chronic obstructive pulmonary disease.

Patients

People aged ≥30 years with a history of smoking who attended public outpatient clinics for primary care services were included in this study.

Methods

A cross-sectional survey in five clinics in Hong Kong using the Breathlessness, Cough, and Sputum Scale, the Lung Function Questionnaire, and office spirometry was conducted.

Results

In total, 731 subjects (response rate =97.9%) completed the questionnaires and spirometry tests. Most of the subjects were men (92.5%) in the older age group (mean age =62.2 years; standard deviation =11.7). Of the 731 subjects, 107 had AO, giving a prevalence of 14.6% (95% confidence interval =12.1–17.2); 45 subjects with AO underwent a postbronchodilator test. By classifying the severity of chronic obstructive pulmonary disease using the Global Initiative for Chronic Obstructive Lung Disease, 27 (60%) were considered to be in mild category and 18 (40%) in moderate category. None of them belonged to the severe or very severe category. The total score of Lung Function Questionnaire showed that majority of the subjects with AO also had chronic cough, wheezing attack, or breathlessness, although most did not show any acute respiratory symptoms in accordance with the Breathlessness, Cough, and Sputum Scale. Diagnosis of AO was positively associated with the number of years of smoking (odds ratio =1.044, P=0.035) and being normal or underweight (odds ratio =1.605, P=0.046). It was negatively associated with a history of hypertension (odds ratio =0.491, P=0.003).

Conclusion

One-seventh of smokers have undiagnosed AO. Spirometry screening of smokers should be considered in order to diagnose AO at an early stage, with an emphasis on smoking cessation.

Identification of STOML2 as a putative novel asthma risk gene associated with IL6R

BACKGROUND

Functional variants in the interleukin-6 receptor gene (IL6R) are associated with asthma risk. We hypothesized that genes co-expressed with IL6R might also be regulated by genetic polymorphisms that are associated with asthma risk. The aim of this study was to identify such genes.

METHODS

To identify genes whose expression was correlated with that of IL6R, we analyzed gene expression levels generated for 373 human lymphoblastoid cell lines by the Geuvadis consortium and for 38 hematopoietic cell types by the Differentiation Map Portal (DMAP) project. Genes correlated with IL6R were then screened for nearby single nucleotide polymorphisms (SNPs) that were significantly associated with both variation in gene expression levels (eSNPs) and asthma risk.

RESULTS

We identified 90 genes with expression levels correlated with those of IL6R and that also had a nearby eSNP associated with disease risk in a published asthma GWAS (N = 20 776). For 16 (18%) genes, the association between the eSNP and asthma risk replicated with the same direction of effect in a further independent published asthma GWAS (N = 27 378). Among the top replicated associations (FDR < 0.05) were eSNPs for four known (IL18R1, IL18RAP, BCL6, and STAT6) and one putative novel asthma risk gene, stomatin-like protein 2 (STOML2). The expression of STOML2 was negatively correlated with IL6R, while eSNPs that increased the expression of STOML2 were associated with an increased asthma risk.

CONCLUSION

The expression of STOML2, a gene that plays a key role in mitochondrial function and T-cell activation, is associated with both IL-6 signaling and asthma risk.

Why and How Limb Muscle Mass and Function Should Be Measured in Patients with Chronic Obstructive Pulmonary Disease

Impaired limb muscle function is a common occurrence in patients with chronic obstructive pulmonary disease (COPD), and it negatively influences exercise tolerance, quality of life, and even survival. Assessment of limb muscle mass and function in COPD is highly encouraged; it should include the quadriceps muscle, but other lower and upper limb muscles may also be evaluated to provide valuable information. Quantification of muscle mass as well as assessment of muscle strength and endurance are suggested. Bioelectrical impedance and dual-energy X-ray absorption can be realistically used in the clinical environment to monitor body composition. Although sophisticated computerized dynamometers provide the most accurate assessment, simple exercise and testing equipment are valid alternatives and they should help in implementing limb muscle function assessment in clinical settings. Isometric measurements, using strain-gauges or hand-held dynamometers, should be favored for their simplicity, availability, and quality of information provided. This perspective provides a rationale for the evaluation of limb muscle mass and function in COPD in routine clinical practice. In addition, measurement techniques used to assess limb muscle mass, strength, endurance, and fatigue in various clinical settings are discussed.

Increased expression of H19/miR-675 is associated with a low fat-free mass index in patients with COPD

BACKGROUND

Loss of muscle mass and strength is a significant comorbidity in patients with chronic obstructive pulmonary disease (COPD) that limits their quality of life and has prognostic implications but does not affect everyone equally. To identify mechanisms that may contribute to the susceptibility to a low muscle mass, we investigated microRNA (miRNA) expression, methylation status, and regeneration in quadriceps muscle from COPD patients and the effect of miRNAs on myoblast proliferation in vitro. The relationships of miRNA expression with muscle mass and strength was also determined in a group of healthy older men.

METHODS

We identified miRNAs associated with a low fat-free mass (FFM) phenotype in a small group of patients with COPD using a PCR screen of 750 miRNAs. The expression of two differentially expressed miRNAs (miR-675 and miR-519a) was determined in an expanded group of COPD patients and their associations with FFM and strength identified. The association of these miRNAs with FFM and strength was also explored in a group of healthy community-dwelling older men. As the expression of the miRNAs associated with FFM could be regulated by methylation, the relative methylation of the H19 ICR was determined. Furthermore, the proportion of myofibres with centralized nuclei, as a marker of muscle regeneration, in the muscle of COPD patients was identified by immunofluorescence.

RESULTS

Imprinted miRNAs (miR-675 and from a cluster, C19MC which includes miR-519a) were differentially expressed in the quadriceps of patients with a low fat-free mass index (FFMI) compared to those with a normal FFMI. In larger cohorts, miR-675 and its host gene (H19) were higher in patients with a low FFMI and strength. The association of miR-519a expression with FFMI was present in male patients with severe COPD. Similar associations of miR expression with lean mass and strength were not observed in healthy community dwelling older men participating in the Hertfordshire Sarcopenia Study. Relative methylation of the H19 ICR was reduced in COPD patients with muscle weakness but was not associated with FFM. In vitro, miR-675 inhibited myoblast proliferation and patients with a low FFMI had fewer centralized nuclei suggesting miR-675 represses regeneration.

CONCLUSIONS

The data suggest that increased expression of miR-675/H19 and altered methylation of the H19 imprinting control region are associated with a low FFMI in patients with COPD but not in healthy community dwelling older men suggesting that epigenetic control of this loci may contribute to a susceptibility to a low FFMI.

Alterations in whole-body arginine metabolism in chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a condition characterized by systemic low-grade inflammation that could increase the production of nitric oxide (NO), of which arginine is the sole precursor. Arginine is derived from the breakdown of protein and through the conversion of citrulline to arginine (de novo arginine production).

OBJECTIVE

Our objective was to study whole-body arginine and citrulline and related metabolism in stable COPD patients.

DESIGN

With the use of stable isotope methodology, we studied whole-body arginine and citrulline rates of appearance, de novo arginine (citrulline-to-arginine flux) and NO (arginine-to-citrulline flux) production, protein synthesis and breakdown rates, and plasma amino acid concentrations in a heterogeneous group of patients with moderate-to-severe COPD [n = 23, mean ± SE age: 65 ± 2 y, forced expiratory volume in 1 s (FEV1): 40% ± 2% of predicted], and a group of healthy older adults (n = 19, mean ± SE age: 64 ± 2 y, FEV1: 95% ± 4% of predicted).

RESULTS

Although plasma arginine and citrulline concentrations were comparable between COPD patients and controls, whole-body arginine (P = 0.015) and citrulline (P = 0.026) rates of appearance were higher in COPD patients and related to a 57% greater de novo arginine production (P < 0.0001). Despite a higher whole-body arginine clearance in COPD patients (P < 0.0001), we found no difference in NO production.

CONCLUSION

In stable patients with moderate-to-severe COPD, endogenous arginine production is upregulated to support a higher arginine utilization that is unrelated to whole-body NO production. This trial was registered at clinicaltrials.gov as NCT01173354 and NCT01172314.

Chronic obstructive pulmonary disease phenotypes and balance impairment

BACKGROUND/OBJECTIVE

Chronic obstructive pulmonary disease (COPD) is a respiratory disease that results in airflow limitation and respiratory distress, also having many nonrespiratory manifestations that affect both function and mobility. Preliminary evidence suggests that balance deficits constitute an important secondary impairment in individuals with COPD. Our objective was to investigate balance performance in two groups of COPD patients with different body compositions and to observe which of these groups are more likely to experience falls in the future.

METHODS

We included 27 stable COPD patients and 17 healthy individuals who performed a series of balance tests. The COPD patients were divided in two groups: emphysematous and bronchitic. Patients completed the activities balance confidence scale and the COPD assessment test questionnaire and afterward performed the Berg Balance Scale, timed up and go, single leg stance and 6-minute walking distance test. We analyzed the differences in the balance tests between the studied groups.

RESULTS

Bronchitic COPD was associated with a decreased value when compared to emphysematous COPD for the following variables: single leg stance (8.7 vs 15.6; P<0.001) and activities balance confidence (53.2 vs 74.2; P=0.001). Bronchitic COPD patients had a significantly higher value of timed up and go test compared to patients with emphysematous COPD (14.7 vs 12.8; P=0.001).

CONCLUSION

Patients with COPD have a higher balance impairment than their healthy peers. Moreover, we observed that the bronchitic COPD phenotype is more likely to experience falls compared to the emphysematous phenotype.

Chronic Obstructive Pulmonary Disease Increases the Risk of Hip Fracture: A Nationwide Population-Based Cohort Study

Hip fractures can lead to functional disability and high mortality rates among elderly patients. The aim of this study was to investigate whether chronic obstructive pulmonary disease (COPD) is a risk factor for hip fracture. A retrospective population-based 4-year cohort study was conducted using case–control matched analysis of data from the Taiwan Longitudinal Health Insurance Database 2005 (LHID2005). Patients with a diagnosis of COPD between January 1, 2004 and December 31, 2007 were enrolled. A 2-stage approach and data from the National Health Interview Survey 2005 were applied to adjust for missing confounders in the LHID2005 cohort. Hazard ratios (HRs) and adjusted HRs were estimated hip fracture risk for the COPD. We enrolled 16,239 patients in the COPD cohort and 48,747 (1:3) patients in non-COPD cohort. The hip fracture incidences were 649 per 100,000 person-years in the study cohort and 369 per 100,000 person-years in non-COPD cohort. The hip fracture HR during the follow-up period was 1.78 (P < 0.001) and the adjusted hip fracture HR was 1.57 (P < 0.001) after adjustment for covariates by using the 2-stage approach method. Patients with COPD were at hip fracture risk and fracture-prevention strategies are essential for better quality of care.

Cachexia in chronic obstructive pulmonary disease: new insights and therapeutic perspective

Cachexia and muscle wasting are well recognized as common and partly reversible features of chronic obstructive pulmonary disease (COPD), adversely affecting disease progression and prognosis. This argues for integration of weight and muscle maintenance in patient care. In this review, recent insights are presented in the diagnosis of muscle wasting in COPD, the pathophysiology of muscle wasting, and putative mechanisms involved in a disturbed energy balance as cachexia driver. We discuss the therapeutic implications of these new insights for optimizing and personalizing management of COPD-induced cachexia.

Klotho and smoking--An interplay influencing the skeletal muscle function deficits that occur in COPD

BACKGROUND

Klotho is an 'anti-ageing' hormone and transmembrane protein; Klotho deficient mice develop a similar ageing phenotype to smokers including emphysema and muscle wasting. The objective of this study was to evaluate skeletal muscle and circulating Klotho protein in smokers and COPD patients and to relate Klotho levels to relevant skeletal muscle parameters. We sought to validate our findings by undertaking complimentary murine studies.

METHODS

Fat free mass, quadriceps strength and spirometry were measured in 87 participants (61 COPD, 13 'healthy smokers' and 13 never smoking controls) in whom serum and quadriceps Klotho protein levels were also measured. Immunohistochemistry was performed to demonstrate the location of Klotho protein in human skeletal muscle and in mouse skeletal muscle in which regeneration was occurring following injury induced by electroporation. In a separate study, gastrocnemius Klotho protein was measured in mice exposed to 77 weeks of smoke or sham air.

RESULTS

Quadriceps Klotho levels were lower in those currently smoking (p = 0.01), irrespective of spirometry, but were not lower in patients with COPD. A regression analysis identified current smoking status as the only independent variable associated with human quadriceps Klotho levels, an observation supported by the finding that smoke exposed mice had lower gastrocnemius Klotho levels than sham exposed mice (p = 0.005). Quadriceps Klotho levels related to local oxidative stress but were paradoxically higher in patients with established muscle wasting or weakness; the unexpected relationship with low fat free mass was the only independent association. Within locomotor muscle, Klotho localized to the plasma membrane and to centralized nuclei in humans and in mice with induced muscle damage. Serum Klotho had an independent association with quadriceps strength but did not relate to quadriceps Klotho levels or to spirometric parameters.

CONCLUSIONS

Klotho is expressed in skeletal muscle and levels are reduced by smoking. Despite this, quadriceps Klotho protein expression in those with established disease appears complex as levels were paradoxically elevated in COPD patients with established muscle wasting. Whilst serum Klotho levels were not reduced in smokers or COPD patients and were not associated with quadriceps Klotho protein, they did relate to quadriceps strength.

Body mass index and chronic airflow limitation in a worldwide population-based study

Nutritional status has been associated with clinical outcome in chronic airflow limitation (CAL), but epidemiological studies are scarce. We aimed to assess the relationship between body mass index (BMI) and CAL, taking into account confounding factors. 18,606 participants (49% male, 21% smokers, mean age: 55.8 ± 11.2 years, mean BMI: 26.7 ± 5.5 kg/m(2)) of the BOLD initiative from 26 sites in 23 countries were included. CAL was defined as post-bronchodilator forced expiratory volume in the first second/forced vital capacity < lower limit of normal. Low and obese BMI were defined as <21 kg/m(2) and ≥30 kg/m(2), respectively. Multivariate logistic regression analysis controlled for confounders age, sex and smoking, and meta-analysis of between-site heterogeneity and clustering. Prevalence of low and obese BMI, smoking history and prevalence of CAL were highly variable between sites. After adjustment for confounders, the meta-analysis of all sites showed that compared to subjects without CAL, low BMI was more frequent, (adjusted odds ratio (OR): 2.23 (95% confidence interval: 1.75, 2.85)) and conversely, obesity was less frequent in subjects with CAL (adjusted OR: 0.78 (0.65, 0.94)). In a worldwide population sample, CAL was associated with lower BMI, even after adjusting for confounding factors age, gender, smoking and between-site heterogeneity. These results indicate a CAL-specific association with body composition.

Effect of Megestrol Acetate and Testosterone on Body Composition and Hormonal Responses in COPD Cachexia

Background: Underweight chronic obstructive pulmonary disease (COPD) patients with involuntary weight loss have a poor prognosis; no effective therapy is currently available. We conducted the first clinical trial seeking to determine whether combination therapy with an appetite stimulant and an anabolic steroid would have beneficial effects on body composition for patients with COPD cachexia. Methods: We conducted a 12-week pilot study in which 4 men and 5 women (age 64±10 y, forced expiratory volume in 1 second [FEV₁] 31±9 %pred., body mass index [BMI] 18±3 kg/m²) with low-normal testosterone levels (average 532±45ng/dl in men and 12.4±5.3ng/dl in women) and weight loss ≥10 lbs over the previous year were treated with oral megestrol acetate 800mg/day plus weekly testosterone enanthate injections, initially 125 mg in men and 40 mg in women, with doses subsequently adjusted targeting circulating nadir testosterone levels of 850 and 300 ng/dl, respectively. Results: On treatment, nadir testosterone level increases averaged 160±250 ng/dl (NS) in men and 322±49 (p<0.001) ng/dl in women. Body weight increased in all individuals, with average end-intervention weight gain of 3.1±2.2 kg (p<0.005). Two women and 2 men had COPD exacerbations and did not complete the 12-week study. In the 5 individuals who completed, dual energy x ray absorptiometry (DEXA) scans revealed an average 2.0±1.5 kg lean mass and 2.3±1.7 kg fat mass increase (each p<0.05). No adverse effects of treatment were detected. Conclusions: Combination therapy reversed the trajectory of involuntary weight loss and increased lean mass in cachectic COPD patients. Though the interventions were apparently well tolerated, participant drop-out rate was high. Larger randomized placebo-controlled long-term studies with functional outcomes are needed.

The 2014 ESPEN Arvid Wretlind Lecture: Metabolism & nutrition: Shifting paradigms in COPD management

COPD is a chronic disease of the lungs, but heterogeneous with respect to clinical manifestations and disease progression. This has consequences for health risk assessment, stratification and management. Heterogeneity can be driven by pulmonary events but also by systemic consequences (e.g. cachexia and muscle weakness) and co-morbidity (e.g. osteoporosis, diabetes and cardiovascular disease). This paper shows how a metabolic perspective on COPD has contributed significantly to understanding clinical heterogeneity and the need for a paradigm shift from reactive medicine towards predictive, preventive, personalized and participatory medicine. These insights have also lead to a paradigm shift in nutritional therapy for COPD from initial ignorance or focusing on putative adverse effects of carbohydrate overload on the ventilatory system to beneficial effects of nutritional intervention on body composition and physical functioning as integral part of disease management. The wider implications beyond COPD as disease have been as clinical model for translational cachexia research.

The relationship between anthropometric indicators and walking distance in patients with chronic obstructive pulmonary disease

Background

Exercise intolerance is a major issue affecting many people with COPD. Six-minute walking distance (6MWD) is a widely used indicator of exercise capacity in patients with COPD. The process is strenuous and time-consuming, especially for patients who have muscle wasting. Anthropometric indicators that reflect body lean mass, such as body mass index (BMI), mid-arm circumference (MAC), and calf circumference (CC), may have value in predicting exercise intolerance.

Purpose

This study attempted to determine the abilities of simple anthropometric indicators including BMI, MAC, and CC in reflecting the exercise intolerance of COPD patients.

Methods

We recruited 136 nonhospitalized ambulatory COPD patients without acute conditions from a general hospital in Taiwan. Each subject’s BMI, MAC, and CC were measured, and they were examined with pulmonary function tests and a 6-minute walk test.

Results

Among the three anthropometric indicators examined, CC showed the strongest correlation with the 6MWD, followed by MAC and BMI. CC was also strongly associated with functional capacity, followed by MAC, according to the receiver operating characteristic curves. CC and MAC, but not BMI, were significantly associated with exercise intolerance according to logistic regression models that controlled for potential confounders.

Conclusion

Among the three variables examined, CC and walking distance may have the strongest association in COPD patients. CC may have value in serving as an adjunct to 6MWD in evaluating exercise intolerance of patients with COPD.

Systemic manifestations of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease is a complex multisystem disease with comorbidities and systemic manifestations that affect respiratory symptoms, exacerbation frequency and mortality. This article gives an overview of these systemic manifestations and their importance, and offers strategies for managing them.

Oxidative and proteolysis-related parameters of skeletal muscle from hamsters with experimental pulmonary emphysema: a comparison between papain and elastase induction

The objective of this study was to investigate whether emphysema induced by elastase or papain triggers the same effects on skeletal muscle, related to oxidative stress and proteolysis, in hamsters. For this purpose, we evaluated pulmonary lesions, body weight, muscle loss, oxidative stress (thiobarbituric acid-reactive substances, total and oxidized glutathiones, chemiluminescence stimulated by tert-butyl hydroperoxide and carbonyl proteins), chymotrypsin-like and calpain-like proteolytic activities and muscle fibre cross-sectional area in the gastrocnemius muscles of emphysemic hamsters. Two groups of animals received different intratracheal inductions of experimental emphysema: by 40 mg/ml papain (EP) or 5.2 IU/100 g animal (EE) elastase (n = 10 animals/group). The control group received intratracheal instillation of 300 μl sterile NaCl 0.9%. Compared with the control group, the EP group had reduced muscle weight (18.34%) and the EE group had increased muscle weight (8.37%). Additionally, tert-butyl hydroperoxide-initiated chemiluminescence, carbonylated proteins and chymotrypsin-like proteolytic activity were all elevated in the EP group compared to the CS group, while total glutathione was decreased compared to the EE group. The EE group showed more fibres with increased cross-sectional areas and increased calpain-like activity. Together, these data show that elastase and papain, when used to induce experimental models of emphysema, lead to different speeds and types of adaptation. These findings provide more information on choosing a suitable experimental model for studying skeletal muscle adaptations in emphysema.

Antagonistic implications of sarcopenia and abdominal obesity on physical performance in COPD

Decreased physical performance due to loss of muscle mass (i.e. sarcopenia) is prevalent in ageing and appears more pronounced in chronic disease. A comprehensive profile of the sarcopenic phenotype in chronic obstructive pulmonary disease (COPD) is not yet available. The aim of the present study was to characterise prevalence, functional implications and predictive value of sarcopenia with or without abdominal obesity in Dutch COPD patients eligible for pulmonary rehabilitation.

505 COPD patients (aged 37–87 years; 57% male) underwent assessment of lung function, body composition and physical functioning, before entering pulmonary rehabilitation. Sarcopenia was assessed by appendicular skeletal muscle index (ASMI) and abdominal obesity by android/gynoid percentage fat mass (A/G%FM) using dual energy X-ray absorptiometry.

86.5% of patients were sarcopenic and showed lower physical functioning, while coexistent abdominal obesity (78.0%) resulted in higher physical functioning. Implications on endurance were less pronounced in women. The predictive value for physical functioning was higher for the “three-compartment” model (ASMI, bone mineral content and A/G%FM) than the “two-compartment” model (fat-free mass index and fat mass index) or “one-compartment” model (body mass index).

In patients eligible for pulmonary rehabilitation, sarcopenia is highly prevalent in all body mass index categories and associated with impaired strength, and in men also with decreased endurance. Abdominal obesity seems to have protective effects on physical functioning. ASMI is a better predictor for physical functioning than fat-free mass index.

Dietary intake of patients with moderate to severe COPD in relation to fat-free mass index: a cross-sectional study

BACKGROUND

Fat-free mass (FFM) depletion has been shown to be a better predictor of mortality than BMI in chronic obstructive pulmonary disease (COPD) patients. The specific aim of the current study was to assess the nutritional status of stable COPD patients in relation to fat free mass index profiles.

METHODS

We investigated 65 male moderate-to-severe stable COPD patients. A self-reported questionnaire was applied about general characteristics and smoking history. Nutritional intake was assessed by using a 54-item quantitative food frequency questionnaire. Weight, height, mid-upper arm circumference (MUAC), waist circumference (WC), handgrip strength and body composition measurements were taken by a trained dietitian. The data were analyzed with SPSS 15.0 software.

RESULTS

The mean age of the patients was 62.1 ± 8.9 years. Among all of the patients 13.8% was underweight (BMI < 21 kg/m(2)) and 18.5% had a low fat-free mass index (FFMI < 16 kg/m(2)). The percentages of the patients who did not meet the daily recommended intakes (RNI) were highest for magnesium (93.8%) and calcium (92.3%). Mean daily consumptions of milk-yogurt, red meat and fruits were significantly low in the low FFMI group compared to normal FFMI group (for all; p < 0.05). Patients with normal FFMI had significantly higher weight, height, WC, MUAC, handgrip strength, fat and fat-free mass than the patients with low FFMI (for all; p < 0.05).

CONCLUSIONS

Dieticians should be aware of COPD patients with low FFMI in order to evaluate the nutritional intake and therefore plan nutritional strategies to improve prognosis of the disease.