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

Obesity and pulmonary disease: unanswered questions

Obesity is associated with risk of pulmonary disease, and adversely affects lung function. The parallel increase in obesity and asthma suggests the two conditions are linked; indeed, they can worsen each other. Obesity and inadequate asthma control are associated with poor quality of life, and place a high economic burden on public health. Although the obesity-lung interaction is a major issue for basic research and clinical studies, various questions remain unanswered. Do intrauterine and early life factors impact on the development of obesity and lung disease? If so, can this be prevented? Asthma is generally more severe in obese subjects, but is adiposity a driver of a new asthma phenotype that features greater morbidity and mortality, worse control and decreased response to medications? Obese individuals have small lung volumes, hence their airway calibre is reduced and airway resistance is increased. What puzzles physicians is whether peripheral airways undergo remodelling, which would increase bronchoconstriction. Obese asthmatics respond suboptimally to anti-inflammatory treatment, which raises the question: 'what drug for what patient?' Life expectancy is decreased in obesity and in chronic pulmonary disorders, but does obesity protect against or trigger chronic obstructive pulmonary disease? The time has come to find answers to these questions.

Weight gain after lung reduction surgery is related to improved lung function and ventilatory efficiency

RATIONALE

Lung volume reduction surgery (LVRS) is associated with weight gain in some patients, but the group that gains weight after LVRS and the mechanisms underlying this phenomenon have not been well characterized.

OBJECTIVES

To describe the weight change profiles of LVRS patients enrolled in the National Emphysema Treatment Trial (NETT) and to correlate alterations in lung physiological parameters with changes in weight.

METHODS

We divided 1,077 non-high-risk patients in the NETT into groups according to baseline body mass index (BMI): underweight (<21 kg/m(2)), normal weight (21-25 kg/m(2)), overweight (25-30 kg/m(2)), and obese (>30 kg/m(2)). We compared BMI groups and LVRS and medical groups within each BMI stratum with respect to baseline characteristics and percent change in BMI (%ΔBMI) from baseline. We examined patients with (ΔBMI ≥ 5%) and without (ΔBMI < 5%) significant weight gain at 6 months and assessed changes in lung function and ventilatory efficiency (Ve/Vco(2)).

MEASUREMENTS AND MAIN RESULTS

The percent change in BMI was greater in the LVRS arm than in the medical arm in the underweight and normal weight groups at all follow-up time points, and at 12 and 24 months in the overweight group. In the LVRS group, patients with ΔBMI ≥ 5% at 6 months had greater improvements in FEV(1) (11.53 ± 9.31 vs. 6.58 ± 8.68%; P < 0.0001), FVC (17.51 ± 15.20 vs. 7.55 ± 14.88%; P < 0.0001), residual volume (-66.20 ± 40.26 vs. -47.06 ± 39.87%; P < 0.0001), 6-minute walk distance (38.70 ± 69.57 vs. 7.57 ± 73.37 m; P < 0.0001), maximal expiratory pressures (12.73 ± 49.08 vs. 3.54 ± 32.22; P = 0.0205), and Ve/Vco(2) (-1.58 ± 6.20 vs. 0.22 ± 8.20; P = 0.0306) at 6 months than patients with ΔBMI < 5% at 6 months.

CONCLUSIONS

LVRS leads to weight gain in nonobese patients, which is associated with improvement in lung function, exercise capacity, respiratory muscle strength, and ventilatory efficiency. These physiological changes may be partially responsible for weight gain in patients who undergo LVRS.

Muscle wasting in animal models of severe illness

Muscle wasting is a serious complication of various clinical conditions that significantly worsens the prognosis of the illnesses. Clinically relevant models of muscle wasting are essential for understanding its pathogenesis and for selective preclinical testing of potential therapeutic agents. The data presented here indicate that muscle wasting has been well characterized in rat models of sepsis (endotoxaemia, and caecal ligation and puncture), in rat models of chronic renal failure (partial nephrectomy), in animal models of intensive care unit patients (corticosteroid treatment combined with peripheral denervation or with administration of neuromuscular blocking drugs) and in murine and rat models of cancer (tumour cell transplantation). There is a need to explore genetically engineered mouse models of cancer. The degree of protein degradation in skeletal muscle is not well characterized in animal models of liver cirrhosis, chronic heart failure and chronic obstructive pulmonary disease. The major difficulties with all models are standardization and high variation in disease progression and a lack of reflection of clinical reality in some of the models. The translation of the information obtained by using these models to clinical practice may be problematic.

Use of a soluble epoxide hydrolase inhibitor in smoke-induced chronic obstructive pulmonary disease

Tobacco smoke-induced chronic obstructive pulmonary disease (COPD) is a prolonged inflammatory condition of the lungs characterized by progressive and largely irreversible airflow limitation attributable to a number of pathologic mechanisms, including bronchitis, bronchiolitis, emphysema, mucus plugging, pulmonary hypertension, and small-airway obstruction. Soluble epoxide hydrolase inhibitors (sEHIs) demonstrated anti-inflammatory properties in a rat model after acute exposure to tobacco smoke. We compared the efficacy of sEHI t-TUCB (trans-4-{4-[3-(4-trifluoromethoxy-phenyl)-ureido]-cyclohexyloxy}-benzoic acid) and the phosphodiesterase-4 (PDE4) inhibitor Rolipram (Biomol International, Enzo Life Sciences, Farmingdale, NY) to reduce lung injury and inflammation after subacute exposure to tobacco smoke over a period of 4 weeks. Pulmonary physiology, bronchoalveolar lavage, cytokine production, and histopathology were analyzed to determine the efficacy of sEHI and Rolipram to ameliorate tobacco smoke-induced inflammation and injury in the spontaneously hypertensive rat. Both t-TUCB and Rolipram inhibited neutrophil elevation in bronchoalveolar lavage. sEHI t-TUCB suppressed IFN-γ, while improving lung function by reducing tobacco smoke-induced total respiratory resistance and tissue damping (small-airway and peripheral tissue resistance). Increases in tobacco smoke-induced alveolar airspace size were attenuated by t-TUCB. Rolipram inhibited the production of airway mucus. Both t-TUCB and Rolipram inhibited vascular remodeling-related growth factor. These findings suggest that sEHI t-TUCB has therapeutic potential for treating COPD by improving lung function and attenuating the lung inflammation and emphysematous changes caused by tobacco smoke. To the best of our knowledge, this is the first report to demonstrate that sEHI exerts significant protective effects after repeated, subacute tobacco smoke-induced lung injury in a rat model of COPD.

[Diaphragm and skeletal muscle dysfunction in COPD]

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is often accompanied by skeletal muscle alterations, resulting in enhanced morbidity and mortality.

STATE OF THE ART

Many studies have highlighted important structural and biochemical modifications in limb and respiratory muscles in COPD. Reviewing the similarities and differences between the two most studied muscles in COPD, the quadriceps and the diaphragm, may provide important clues about the mechanisms dictating muscle changes that occur in this disease.

PERSPECTIVES

Though these two muscle groups share a common systemic environment, discrepancies are observed in their respective alterations. These phenotypic differences suggest that, in addition to systemic factors, the local microenvironment must participate in the reorganization seen in these two muscles in COPD.

CONCLUSIONS

The current review introduces the alterations observed in the quadriceps and diaphragm in the context of COPD and suggests possible signaling pathways involved in the development of muscle dysfunction.

Strength training increases maximum working capacity in patients with COPD--randomized clinical trial comparing three training modalities

BACKGROUND AND OBJECTIVE

Skeletal muscle dysfunction contributes to exercise limitation in patients with chronic obstructive pulmonary disease (COPD). Strength training increases muscle strength and muscle mass, but there is an ongoing debate on the additional effect concerning the exercise capacity. The purpose of this study was to compare the effects of three different exercise modalities in patients with COPD including endurance training (ET), progressive strength training (ST) and the combination of strength training and endurance training (CT).

DESIGN

A prospective randomized trial.

METHODS

Thirty-six patients with COPD were randomly allocated either to ET, ST, or CT. Muscle strength, cardiopulmonary exercise testing, lung function testing and quality of life were assessed before and after a 12-week training period.

RESULTS

Exercise capacity (Wmax) increased significantly in all three training groups with increase of peak oxygen uptake (VO2peak) in all three groups, reaching statistical significance in the ET group and the CT group. Muscle strength (leg press, bench press, bench pull) improved in all three training groups, with a higher improvement in the ST (+39.3%, +20.9%, +20.3%) and the CT group (+43.3%, +18.1%, +21.6%) compared to the ET group (+20.4%, +6.4%, +12.1%).

CONCLUSIONS

Progressive strength training alone increases not only muscle strength and quality of life, but also exercise capacity in patients with COPD, which may have implications in prescription of training modality. CLINICALTRIALS.GOV IDENTIFIER: NCT01091623.

The National Emphysema Treatment Trial (NETT): Part I: Lessons learned about emphysema

The National Emphysema Treatment Trial (NETT) was a multicenter prospective randomized controlled trial that compared optimal medical treatment, including pulmonary rehabilitation, with optimal medical treatment plus lung volume reduction surgery (LVRS). It was the largest and most complete collection of patient demographic, clinical, physiological, and radiographic data ever compiled in severe emphysema. NETT investigated the effects of optimal medical management and LVRS on short- and long-term survival, as well as lung function, exercise performance, and quality of life. NETT also provided much information regarding the evaluation and prognosis of severe emphysema; specifically the important negative influences that hyperinflation and small airway disease have on survival. NETT emphasized the importance of addressing nonpulmonary issues such as nutrition, cardiac disease, anxiety, and depression in emphysema. NETT demonstrated that physiological, genomic, and radiographic phenotype can predict patient survival as well as response to treatment. Because the major purpose of NETT was to compare bilateral LVRS with optimal medical treatment in emphysema, patients enrolled into NETT were comprehensively characterized and selected to have a specific window of airflow obstruction and hyperinflation and to lack significant comorbidities. The NETT patient population’s restrictive features offer distinct advantages (well-characterized predominant emphysematous phenotype) and disadvantages (lack of comorbidities and significant chronic bronchitis) that must be considered when interpreting the implications of these results. Herein, we provide a summary of the major NETT findings that provide insight into the evaluation and medical treatment of emphysema.

Energy expenditure at rest and during walking in patients with chronic respiratory failure: a prospective two-phase case-control study

Background

Measurements of Energy Expenditure (EE) at rest (REE) and during physical activities are increasing in interest in chronic patients. In this study we aimed at evaluating the validity/reliability of the SenseWear®Armband (SWA) device in terms of REE and EE during assisted walking in Chronic Respiratory Failure (CRF) patients receiving long-term oxygen therapy (LTOT).

Methodology/Principal Findings

In a two-phase prospective protocol we studied 40 severe patients and 35 age-matched healthy controls. In phase-1 we determined the validity and repeatability of REE measured by SWA (REEa) in comparison with standard calorimetry (REEc). In phase-2 we then assessed EE and Metabolic Equivalents-METs by SWA during the 6-minute walking test while breathing oxygen in both assisted (Aid) or unassisted (No-Aid) modalities. When compared with REEc, REEa was slightly lower in patients (1351±169 vs 1413±194 kcal/day respectively, p<0.05), and less repeatable than in healthy controls (0.14 and 0.43 coefficient respectively). COPD patients with CRF patients reported a significant gain with Aid as compared with No-Aid modality in terms of meters walked, perceived symptoms and EE.

Conclusions/Significance

SWA provides a feasible and valid method to assess the energy expenditure in CRF patients on LTOT, and it shows that aided walking results in a substantial energy saving in this population.

[Concept and significance of a subjective and multiple index system of clinical evaluation for traditional Chinese medicine]

Traditional Chinese medicine (TCM) has its own system of diagnosis and treatment theory, and its methods for evaluating clinical efficacy are different from those of Western medicine. Applying evaluation techniques and methods that are used in Western medicine mechanically to TCM will not work. So building evaluation techniques, which adhere to regulations and characteristics of TCM, is necessary and imperative. As the quality of life and patient-reported outcome instruments were brought into practice and developed, clinical evaluation ideas and methods for TCM are provided with an opportunity for development. This article puts forward the concept of subjective complex outcomes (SCOs), which constitutes subjective feelings gained from the patient, doctor and caregiver, different from laboratory parameters. SCOs provide a multidimensional and complex health-related quality of life (HRQL) assessment and focus on the source of assessment information of diseases. This article also introduces a case study building SCO methods of TCM treatment for chronic obstructive pulmonary diseases, in order to promote discussion and provide a platform for future research.

Cachexia as a major underestimated and unmet medical need: facts and numbers

Cachexia is a serious, however underestimated and underrecognised medical consequence of malignant cancer, chronic heart failure (CHF), chronic kidney disease (CKD), chronic obstructive pulmonary disease (COPD), cystic fibrosis, rheumatoid arthritis, Alzheimer's disease, infectious diseases, and many other chronic illnesses. The prevalence of cachexia is high, ranging from 5% to 15% in CHF or COPD to 60% to 80% in advanced cancer. By population prevalence, the most frequent cachexia subtypes are in order: COPD cachexia, cardiac cachexia (in CHF), cancer cachexia, and CKD cachexia. In industrialized countries (North America, Europe, Japan), the overall prevalence of cachexia (due to any disease) is growing and currently about 1%, i.e., about nine million patients. The relative prevalence of cachexia is somewhat less in Asia, but is a growing problem there as well. In absolute terms, cachexia is, in Asia (due to the larger population), as least as big a problem as in the Western world. Cachexia is also a big medical problem in South America and Africa, but data are scarce. A consensus statement recently proposed to diagnose cachexia in chronic diseases when there is weight loss exceeding 5% within the previous 3-12 months combined with symptoms characteristic for cachexia (e.g., fatigue), loss of skeletal muscle and biochemical abnormalities (e.g., anemia or inflammation). Treatment approaches using anabolics, anti-catabolic therapies, appetite stimulants, and nutritional interventions are under development. A more thorough understanding of the pathophysiology of cachexia development and progression is needed that likely will lead to combination therapies being developed. These efforts are greatly needed as presence of cachexia is always associated with high-mortality and poor-symptom status and dismal quality of life. It is thought that in cancer, more than 30% of patients die due to cachexia and more than 50% of patients with cancer die with cachexia being present. In other chronic illnesses, one can estimate that up to 30% of patients die with some degree of cachexia being present. Mortality rates of patients with cachexia range from 10% to 15% per year (COPD), to 20% to 30% per year (CHF, CKD) to 80% in cancer.

Efeitos do exercício resistido de membros superiores na força muscular periférica e na capacidade funcional do paciente com DPOC

INTRODUÇÃO: A disfunção muscular periférica na doença pulmonar obstrutiva crônica (DPOC) contribui diretamente para a intolerância ao exercício físico, porém ainda não há consenso sobre estratégias adequadas de treinamento físico para esses pacientes. OBJETIVO: Avaliar o efeito do exercício resistido de membros superiores (MMSS) em pacientes com DPOC moderada a muito grave no ganho de força e na capacidade funcional. MÉTODOS: Doze pacientes com DPOC foram divididos em dois grupos: controle (GC) e treinado (GT). O GT realizou treinamento de força, três vezes por semana, durante seis semanas, com carga de 80% de uma repetição máxima (RM). Antes e após o tratamento, foram realizados os testes de 1 RM e o Pegboard and Ring Test (PBRT) em ambos os grupos. RESULTADOS: Após o tratamento, verificou-se aumento significativo da força muscular no GT (aumento de 52% no supino sentado e 22% no pulley, com p < 0,05); e quanto ao PBRT, não houve diferença significativa em ambos os grupos. CONCLUSÃO: O treinamento de força de MMSS com duração de seis semanas foi capaz de aumentar a força muscular, mas não a funcionalidade de pacientes com DPOC moderada a muito grave.

Systemic effects of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is associated with important extrapulmonary, or systemic, effects. There is systemic as well as pulmonary inflammation in COPD and this, together with systemic oxidative stress, contributes to their development. Skeletal muscle dysfunction contributes to exercise limitation. There is a loss of muscle mass and a reduction in the proportion of type 1 fibers. Sedentarism, hypoxia, corticosteroid therapy, nutritional depletion and systemic inflammation may contribute to its development. Weight loss is another important effect. It is associated with a worse prognosis, which changes with therapy and may be due to reductions in calorie intake, changes in intermediate metabolism and effects of systemic inflammation. Cardiovascular disease is a frequent cause of death in COPD and coronary artery disease, left ventricular failure and arrhythmias are systemic effects of COPD, as well as comorbidities sharing a common etiology. Exacerbations of COPD may increase the risk of coronary events by increasing the level of systemic inflammation. Osteoporosis is more common in COPD (even after adjusting for corticosteroid usage) and may be due to a combination of inactivity and the effects of systemic inflammation. COPD is also associated with systemic endothelial dysfunction and CNS abnormalities (including depression), which may also be due to the effects of systemic inflammation. These systemic effects respond to COPD treatments, including pulmonary rehabilitation, nutritional supplementation and inhaled corticosteroids, as well as specific drugs, such as bisphosphonates or diuretics. There is growing evidence that novel approaches, such as the use of statins, may also be of value.

The prevalence of quadriceps weakness in COPD and the relationship with disease severity

Quadriceps strength relates to exercise capacity and prognosis in chronic obstructive pulmonary disease (COPD). We wanted to quantify the prevalence of quadriceps weakness in COPD and hypothesised that it would not be restricted to patients with severe airflow obstruction or dyspnoea. Predicted quadriceps strength was calculated using a regression equation (incorporating age, sex, height and fat-free mass), based on measurements from 212 healthy subjects. The prevalence of weakness (defined as observed values 1.645 standardised residuals below predicted) was related to Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage and Medical Research Council (MRC) dyspnoea score in two cohorts of stable COPD outpatients recruited from the UK (n = 240) and the Netherlands (n = 351). 32% and 33% of UK and Dutch COPD patients had quadriceps weakness. A significant proportion of patients in GOLD stages 1 and 2, or with an MRC dyspnoea score of 1 or 2, had quadriceps weakness (28 and 26%, respectively). These values rose to 38% in GOLD stage 4, and 43% in patients with an MRC Score of 4 or 5. Quadriceps weakness was demonstrable in one-third of COPD patients attending hospital respiratory outpatient services. Quadriceps weakness exists in the absence of severe airflow obstruction or breathlessness.

Smoking status and tumor necrosis factor-alpha mediated systemic inflammation in COPD patients

BACKGROUND

Smoking cause airway and systemic inflammation and COPD patients present low grade inflammation in peripheral blood. However, data on the influence of smoking itself on systemic inflammation in COPD patients are scarce. This study investigated the association between inflammation, smoking status, and disease.

METHODS

A cross-sectional analysis comparing 53 COPD ex-smokers, 24 COPD current smokers, 24 current smoker controls and 34 never-smoker controls was performed. Assessments included medical history, body composition, spirometry, and plasma concentration of tumor necrosis factor-alpha (TNF-alpha), interleukins (IL)-6, IL-8, and C-reactive protein (CRP).

RESULTS

Our exploratory analysis showed that serum TNF-alpha was higher in COPD current smokers [4.8(4.2-5.8)pg/mL] and in current smoker controls [4.8 (4.2-6.1) pg/mL] when compared to COPD ex-smokers [4.3 (3.9-4.9)pg/mL; p = 0.02] and to never-smoker controls [3.7 (3.4-4.0)pg/mL; p < 0.001]. Multiple regression results with and without adjustment for covariates were consistent with the hypothesis that TNF-alpha levels were associated with smoking status in both models (p < 0.001 and p < 0.001). IL-6 and CRP were significantly higher in COPD patients when compared to smoker and never-smoker controls and the multiple regression analysis confirmed the association of these mediators with disease, but not with smoking status (p < 0.001 and p < 0.001). IL-8 had only a borderline association with disease in both models (p = 0.069 and p = 0.053). No influence of disease severity, inhaled corticosteroid, fat-free mass (FFM) depletion and long term oxygen therapy (LTOT) use on systemic inflammation was found.

CONCLUSION

Smoking may influence TNF-alpha mediated systemic inflammation, which, in turn, may account for some of the benefits observed in patients with COPD who stop smoking.

Methods for the assessment of peripheral muscle fatigue and its energy and metabolic determinants in COPD

It has been well established that, in addition to the pulmonary involvement, COPD has systemic consequences that can lead to peripheral muscle dysfunction, with greater muscle fatigue, lower exercise tolerance and lower survival in these patients. In view of the negative repercussions of early muscle fatigue in COPD, the objective of this review was to discuss the principal findings in the literature on the metabolic and bioenergy determinants of muscle fatigue, its functional repercussions, as well as the methods for its identification and quantification. The anatomical and functional substrate of higher muscle fatigue in COPD appears to include lower levels of high-energy phosphates, lower mitochondrial density, early lactacidemia, higher serum ammonia and reduced muscle perfusion. These alterations can be revealed by contraction failure, decreased firing rates of motor units and increased recruitment of motor units in a given activity, which can be functionally detected by a reduction in muscle strength, power and endurance. This review article also shows that various types of muscle contraction regimens and protocols have been used in order to detect muscle fatigue in this population. With this understanding, rehabilitation strategies can be developed in order to improve the resistance to muscle fatigue in this population.

Nutritional status is related to fat-free mass, exercise capacity and inspiratory strength in severe chronic obstructive pulmonary disease patients

INTRODUCTION

Being overweight or obese is associated with a higher rate of survival in patients with advanced chronic obstructive pulmonary disease (COPD). This paradoxical relationship indicates that the influence of nutritional status on functional parameters should be further investigated.

OBJECTIVE

To investigate the impact of nutritional status on body composition, exercise capacity and respiratory muscle strength in severe chronic obstructive pulmonary disease patients.

METHODS

Thirty-two patients (nine women) were divided into three groups according to their body mass indices (BMI): overweight/obese (25 < or = BMI < or = 34.9 kg/m(2), n=8), normal weight (18.5 < or = BMI < or = 24.9 kg/m(2), n=17) and underweight (BMI <18.5 kg/m(2), n=7). Spirometry, bioelectrical impedance, a six-minute walking distance test and maximal inspiratory and expiratory pressures were assessed.

RESULTS

Airway obstruction was similar among the groups (p=0.30); however, overweight/obese patients had a higher fat-free mass (FFM) index [FFMI=FFM/body weight(2) (mean+/-SEM: 17+/-0.3 vs. 15+/-0.3 vs. 14+/-0.5 m/kg(2), p<0.01)], exercise capacity (90+/-8 vs. 79+/-6 vs. 57+/-8 m, p=0.02) and maximal inspiratory pressure (63+/-7 vs. 57+/-5 vs. 35+/-8 % predicted, p=0.03) in comparison to normal weight and underweight patients, respectively. In addition, on backward multiple regression analysis, FFMI was the unique independent predictor of exercise capacity (partial r=0.52, p<0.01).

CONCLUSIONS

Severe chronic obstructive pulmonary disease (COPD) patients who were overweight or obese had a greater FFM, exercise capacity and inspiratory muscle strength than patients with the same degree of airflow obstruction who were of normal weight or underweight, and higher FFM was independently associated with higher exercise capacity. These characteristics of overweight or obese patients might counteract the drawbacks of excess weight and lead to an improved prognosis in COPD.

Factors associated with the minimal clinically important difference for health-related quality of life after physical conditioning in patients with COPD

OBJECTIVE

To identify factors associated with the minimal clinically important difference (MCID) for health-related quality of life (HRQoL) after physical conditioning in patients with COPD.

METHODS

Thirty-five patients were submitted to a 12-week program of physical conditioning (strength training plus low-intensity aerobic exercise). Body composition, incremental treadmill test results, endurance treadmill test results, six-minute walk test results, peripheral muscle strength, MIP, baseline dyspnea index (BDI) and Saint George's Respiratory Questionnaire (SGRQ) scores were assessed at baseline and after the program, thus allowing the variations (Delta) to be calculated. The MCID for HRQoL was defined as a reduction of > 4% in the SGRQ total score. Subjects who responded to the program, achieving the MCID for HRQoL, were allocated to the responders (R) group (n = 24), and the remainder were allocated to the non-responders (NR) group (n = 11).

RESULTS

The values obtained for the following variables were significantly higher in group R than in group NR (p < 0.05): FEV1 (1.48 + or - 0.54 L vs. 1.04 + or - 0.34 L); VEF1/FVC (47.9 + or - 11.7% vs. 35.5 + or - 10.7%); PaO2 (74.1 + or - 9.7 mmHg vs. 65.0 + or - 8.9 mmHg); and DeltaBDI, expressed as median and interquartile range (2.0 [0.0-3.5] vs. 0.0 [0.0-1.0]). The DeltaBDI correlated significantly with the DeltaSGRQ symptoms domain score, activity domain score and total score (r = 0.44, 0.60 and 0.62, respectively, p < 0.01 for all). After logistic regression, only DeltaBDI remained as a predictor of MCID for HRQoL.

CONCLUSIONS

Achieving the MCID for HRQoL after physical conditioning is associated with dyspnea reduction in COPD patients. Therefore, there is a need to develop treatment strategies designed to interrupt the dyspnea-inactivity-dyspnea cycle in such patients.

Structural and functional changes of peripheral muscles in chronic obstructive pulmonary disease patients

PURPOSE OF REVIEW

The purpose of this review is to identify new advances in our understanding of skeletal muscle dysfunction in patients with chronic obstructive pulmonary disease (COPD).

RECENT FINDINGS

Recent studies have confirmed the relevance of muscle dysfunction as an independent prognosis factor in COPD. Animal studies have shed light on the molecular mechanisms governing skeletal muscle hypertrophy/atrophy. Recent evidence in patients with COPD highlighted the contribution of protein breakdown and mitochondrial dysfunction as pathogenic mechanisms leading to muscle dysfunction in these patients.

SUMMARY

COPD is a debilitating disease impacting negatively on health status and the functional capacity of patients. COPD goes beyond the lungs and incurs significant systemic effects among which muscle dysfunction/wasting is one of the most important. Muscle dysfunction is a prominent contributor to exercise limitation, healthcare utilization and an independent predictor of morbidity and mortality. Gaining more insight into the molecular mechanisms leading to muscle dysfunction/wasting is key for the development of new and tailored therapeutic strategies to tackle skeletal muscle dysfunction/wasting in COPD patients.

Obesity, adipokines, and lung disease

This review summarizes the state of the current literature relating to the associations of lung disease on obesity and adipokines (proteins produced by adipose tissue) in humans. Obesity is an independent risk factor for asthma. Recent studies suggest that obesity is also an independent risk factor for chronic airflow obstruction, as is seen with chronic obstructive pulmonary disease (COPD). The mechanistic basis for these associations in humans is not established, although a possible role for adipokines has been invoked. Leptin, a proinflammatory adipokine, and adiponectin, an anti-inflammatory adipokine, are causally associated with asthma in mice. Although human studies are currently inconclusive, high-serum leptin and low-serum adiponectin concentrations predict asthma, independent of obesity, in select population groups, such as premenopausal women in the United States. In contradistinction, low-serum leptin and high-serum adiponectin concentrations are associated with stable COPD, although these associations are likely confounded by fat mass. Interestingly, leptin may promote systemic and airway inflammation in stable COPD patients. On the other hand, COPD may upregulate systemic and lung adiponectin expression. The precise mechanism and significance of the associations between these adipokines and lung disease at the current stage is confusing and frankly paradoxical in places. This area of research needs additional study that may open up novel therapeutic strategies for these lung diseases.

Fat-free mass change after nutritional rehabilitation in weight losing COPD: role of insulin, C-reactive protein and tissue hypoxia

BACKGROUND

Fat-free mass (FFM) depletion marks the imbalance between tissue protein synthesis and breakdown in chronic obstructive pulmonary disease (COPD). To date, the role of essential amino acid supplementation (EAAs) in FFM repletion has not been fully acknowledged. A pilot study was undertaken in patients attending pulmonary rehabilitation.

METHODS

28 COPD patients with dynamic weight loss > 5% over the last 6 months were randomized to receive EAAs embedded in a 12-week rehabilitation program (EAAs group n = 14), or to the same program without supplementation (C group n = 14). Primary outcome measures were changes in body weight and FFM, using dual X-ray absorptiometry (DEXA).

RESULTS

At the 12th week, a body weight increment occurred in 92% and 15% of patients in the EAAs and C group, respectively, with an average increase of 3.8 +/- 2.6 kg (P = 0.0002) and -0.1 +/- 1.1 kg (P = 0.81), respectively. A FFM increment occurred in 69% and 15% of EAAs and C patients, respectively, with an average increase of 1.5 +/- 2.6 kg (P = 0.05) and -0.1 +/- 2.3 kg (P = 0.94), respectively. In the EAAs group, FFM change was significantly related to fasting insulin (r(2) 0.68, P < 0.0005), C-reactive protein (C-RP) (r(2) = 0.46, P < 0.01), and oxygen extraction tension (PaO(2x)) (r(2) = 0.46, P < 0.01) at end of treatment. These three variables were highly correlated in both groups (r > 0.7, P < 0.005 in all tests).

CONCLUSIONS

Changes in FFM promoted by EAAs are related to cellular energy and tissue oxygen availability in depleted COPD. Insulin, C-RP, and PaO(2x) must be regarded as clinical markers of an amino acid-stimulated signaling to FFM accretion.

Whole-Body versus Local DXA-Scan for the Diagnosis of Osteoporosis in COPD Patients

Background. Osteoporosis is an extrapulmonary effect of chronic obstructive pulmonary disease (COPD). Diagnosis of osteoporosis is based on BMD measured by DXA-scan. The best location for BMD measurement in COPD has not been determined. Aim of this study was to assess whole-body BMD and BMD of the hip and lumbar spine (local DXA) in COPD patients and compare the prevalence of osteoporosis at these locations. Methods. Whole body as well as local DXA-scan were made in 168 COPD patients entering pulmonary rehabilitation. Patient-relevant characteristics were assessed. Prevalence of osteoporosis was determined. Characteristics of patients without osteoporosis were compared to patients with osteoporosis on local DXA. Results. A higher prevalence of osteoporosis was found using local DXA compared to whole-body DXA (39% versus 21%). One quarter of patients without osteoporosis on whole body-DXA did have osteoporosis on local DXA. Significant differences in patient characteristics between patients without osteoporosis based on both DXA measurements and patients with osteoporosis based on local DXA only were found. Conclusions. DXA of the hip and lumbar spine should be made to assess bone mineral density in COPD patients. The lowest T-score of these locations should be used to diagnose osteoporosis.

Vitamin D status in relation to nutritional depletion and muscle function in patients with advanced pulmonary disease

Muscle weakness is an important complication of advanced pulmonary disease and it is associated with reduced functional activity and lower survival. Vitamin D may be involved in muscle function. The aim of this study was to investigate determinants of calcidiol (25-hydroxycholecalciferol, the major circulating indicator of vitamin D) status and associations between vitamin D metabolites and muscle function in relation to nutritional depletion. Fifty-two percent of the underweight patients (n = 42) and 55% of the normal-weight ones (n = 29) had vitamin D deficiency (< 37.5 nmol/L). The resulting models of linear regression showed that, for the calcidiol model, 24.7% of the variation for calcidiol was explained by fat mass index, vitamin D intake, and FEV(1)/FVC. The results further suggested that vitamin D intake was a stronger predictor of calcidiol status in the underweight patients than in the normal-weight ones. In the resulting models for 6-minute walking distance, calcidiol was a significant predictor, which tended to be more marked in the underweight patients than in the normal-weight ones. Low serum calcidiol concentration was associated with fat mass, lung obstruction, and low intake of vitamin D, especially in the underweight patients, and calcidiol was a predictor of walking distance.

Endurance and Resistance Training in Radically Treated Respiratory Cancer patients: A Pilot Study

Introduction. Respiratory cancer and its treatment are known to contribute to muscle weakness and functional impairment. Aim. To assess the effects of rehabilitation in patients with respiratory cancer. Methods. Radically treated respiratory cancer patients were included in a 12-week multidisciplinary rehabilitation program. Results. 16 patients (age: 61 ± 7 years; FEV₁: 57 ± 16% pred.) showed a reduced exercise tolerance (VO₂max: 56 ± 15% pred.; 6 MWD: 67 ± 11% pred.), muscle force (PImax: 54 ± 22% pred.; QF: 67 ± 16% pred.), and quality of life (CRDQd: 17 ± 5 points; CRDQf: 16 ± 5 points). Exercise tolerance, muscle force, and quality of life improved significantly after rehabilitation. Conclusion. Radically treated patients with respiratory cancer have a decreased exercise capacity, muscle force, and quality of life. 12 weeks of rehabilitation leads to a significant improvement in exercise capacity, respiratory muscle force, and quality of life.

Clinical pharmacy-led disease and medicine management programme for patients with COPD

AIM

The aim was to investigate the impact of a disease and medicine management programme, focusing on self-management in patients with chronic obstructive pulmonary disease (COPD).

METHODS

One hundred and seventy-three patients (mean age 67 years; 54% female) were recruited; 86 patients were randomly assigned to an intervention group and 87 to a usual care (control) group. Intervention patients received education on disease state, medications and breathing techniques. Patients were given booklets and a customized action plan (antibiotic and oral steroid to be initiated promptly by patients for exacerbations). Patients were followed up at 6 and 12 months during a scheduled visit. The St George's Respiratory Questionnaire (SGRQ), COPD Knowledge and Morisky adherence questionnaires were administered to all patients at baseline, 6 and 12 months. Outcome measures included hospital admissions, emergency department (ED) visits, health-related quality of life (HRQoL) and medication adherence.

RESULTS

Over the 12-month period in the intervention group, ED visits decreased by 50% (P= 0.02) and hospitalization by approximately 60% (P= 0.01). On the SGRQ, differences reached statistical significance on the symptom (-7.5; P= 0.04) and impact (-7.4; P= 0.03) subscales but not on the physical activity subscale. There was a significant difference between the intervention and usual care groups regarding knowledge scores (75.0 vs. 59.3; P= 0.001) and good adherence to medication (77.8% vs. 60.0%, P= 0.019). There was no significant difference regarding smoking between study groups.

CONCLUSIONS

The clinical pharmacy-led management programme can improve adherence, reduce the need for hospital care in patients with COPD and improve aspects of their HRQoL.

Clinical pharmacy-led disease and medicine management programme for patients with COPD

AIM

The aim was to investigate the impact of a disease and medicine management programme, focusing on self-management in patients with chronic obstructive pulmonary disease (COPD).

METHODS

One hundred and seventy-three patients (mean age 67 years; 54% female) were recruited; 86 patients were randomly assigned to an intervention group and 87 to a usual care (control) group. Intervention patients received education on disease state, medications and breathing techniques. Patients were given booklets and a customized action plan (antibiotic and oral steroid to be initiated promptly by patients for exacerbations). Patients were followed up at 6 and 12 months during a scheduled visit. The St George's Respiratory Questionnaire (SGRQ), COPD Knowledge and Morisky adherence questionnaires were administered to all patients at baseline, 6 and 12 months. Outcome measures included hospital admissions, emergency department (ED) visits, health-related quality of life (HRQoL) and medication adherence.

RESULTS

Over the 12-month period in the intervention group, ED visits decreased by 50% (P= 0.02) and hospitalization by approximately 60% (P= 0.01). On the SGRQ, differences reached statistical significance on the symptom (-7.5; P= 0.04) and impact (-7.4; P= 0.03) subscales but not on the physical activity subscale. There was a significant difference between the intervention and usual care groups regarding knowledge scores (75.0 vs. 59.3; P= 0.001) and good adherence to medication (77.8% vs. 60.0%, P= 0.019). There was no significant difference regarding smoking between study groups.

CONCLUSIONS

The clinical pharmacy-led management programme can improve adherence, reduce the need for hospital care in patients with COPD and improve aspects of their HRQoL.

Development and characterization of a rat model of chronic obstructive pulmonary disease (COPD) induced by sidestream cigarette smoke

Cigarette smoke (CS) induced chronic obstructive pulmonary disease (COPD) has been emerging as a great health problem in China. However, lack of appropriate animal model slows down the progress in understanding pathogenesis of the disease. The aim of current study is to establish and evaluate a more adequate rat model of COPD. Study was performed with rats exposed to sidestream cigarette smoke 2h/d and 7d/wk for 2, 4, 6, 8, 10, 12, 24 and 36 wk in a CS chamber (carbon monoxide concentration was 231+/-11ppm). The lung function was determined by using the forced oscillation technique. Pathologic changes were determined by using histological analyses and mucin measurement. Following 36-wk exposure, airway resistance (Raw) and respiratory system elastance (Ers) in CS group rats was elevated by 28.5% and 37.5%, respectively. Up to 4.1-, 2.3- and 1.4-fold increase in the number of neutrophils, macrophages and lymphocytes was observed in the BALF of CS rats. Using quantitative histomorphology techniques, it was found that mean linear intercept (MLI) and mean alveolar airspace (MAA) of CS rats increased by 44.8% and 43.7%, respectively, indicating the occurrence of emphysema. The characteristics of chronic bronchitis including hyperplasia of bronchial epithelial cells, hypersecretion of mucus and development of peribronchial fibrosis were also found in rat lungs. CS group rats showed 43% body weight gain reduction. To conclude, a more adequate sidestream cigarette smoke rat COPD model was established, which will be beneficial for understanding the pathogenesis of the disease and for evaluation of drug effectiveness.

Advances in understanding and assessing malnutrition

PURPOSE OF REVIEW

To describe the varying views on the pathophysiology of malnutrition in different populations and the definitions that result from these views. To propose an umbrella definition for different malnutrition syndromes and principles of assessment of nutritional state.

RECENT FINDINGS

At present, tacitly or openly inflammatory activity is considered to contribute to the malnourished state. The malnourished state, therefore, arises from a combination of inflammation and a disturbed nutrient balance (undernutrition or overnutrition). The undernourished category of malnutrition leads to loss of body cell mass, which, together with inflammation diminish host response and quality of life. On the basis of these findings, malnutrition may be assessed by estimating nutrient balance but, subsequently, to measure body composition (muscle mass), inflammatory activity (plasma albumin and C-reactive protein) and muscle endurance and force. Changes in muscle function in patients with chronic obstructive pulmonary disease are associated with changes in fiber composition. Few data exist in other malnourished states.

SUMMARY

There is an increasing acknowledgement of the fact that malnutrition is caused by disturbances in nutrient balance and inflammatory activity. This leads to changes in body composition and diminished function. An umbrella definition has been proposed including the pathogenetic factors, underlying the different malnutrition syndromes and dictating the methods to assess malnutrition.

Targeted treatment in COPD: a multi-system approach for a multi-system disease

Chronic obstructive pulmonary disease is a varied condition when examined from a number of different perspectives including factors which influence disease development, pathological process and clinical features. There may be a complex interaction between the degree by which each of these processes influences the development of COPD and the subsequent clinical phenotype with which the patient presents. The varied host response and subsequent clinical phenotype has generated much interest in recent years. It is possible that failure of treatment to impact on mortality and reverse the disease process is because of the heterogeneous nature of the condition. Identification and targeted treatment of clinical and pathological phenotypes within the broad spectrum of COPD may therefore improve outcome. This article will review previous work which has attempted to phenotype COPD and identify if specific treatment for these phenotypes has been shown to be of benefit. It will examine the work on pathological processes and clinical manifestations, both pulmonary and systemic, and will focus on pharmacological therapies.

Effect of three exercise programs on patients with chronic obstructive pulmonary disease

We compared the effect of three different exercise programs on patients with chronic obstructive pulmonary disease including strength training at 50_80% of one-repetition maximum (1-RM) (ST; N = 11), low-intensity general training (LGT; N = 13), or combined training groups (CT; N = 11). Body composition, muscle strength, treadmill endurance test (TEnd), 6-min walk test (6MWT), Saint George's Respiratory Questionnaire (SGRQ), and baseline dyspnea (BDI) were assessed prior to and after the training programs (12 weeks). The training modalities showed similar improvements (P > 0.05) in SGRQ-total (ST = 13 +/- 14%; CT = 12 +/- 14%; LGT = 11 +/- 10%), BDI (ST = 1.8 +/- 4; CT = 1.8 +/- 3; LGT = 1 +/- 2), 6MWT (ST = 43 +/- 51 m; CT = 48 +/- 50 m; LGT = 31 +/- 75 m), and TEnd (ST = 11 +/- 20 min; CT = 11 +/- 11 min; LGT = 7 +/- 5 min). In the ST and CT groups, an additional improvement in 1-RM values was shown (P < 0.05) compared to the LGT group (ST = 10 +/- 6 to 57 +/- 36 kg; CT = 6 +/- 2 to 38 +/- 16 kg; LGT = 1 +/- 2 to 16 +/- 12 kg). The addition of strength training to our current training program increased muscle strength; however, it produced no additional improvement in walking endurance, dyspnea or quality of life. A simple combined training program provides benefits without increasing the duration of the training sessions.

Influence of lean body mass on cardiopulmonary repercussions during the six-minute walk test in patients with COPD

OBJECTIVE

Although lean body mass (LBM) has been associated with mortality in patients with COPD, its influence on functional limitation is not clear. The objective of this study was to analyze the cardiopulmonary variables in COPD patients with or without LBM depletion, prior to and after the six-minute walk test (6MWT).

METHODS

We evaluated COPD patients, 32 with LBM depletion and 36 without. All patients underwent clinical evaluation, spirometry, evaluation of body mass composition and 6MWT, as well as completing questionnaires related to quality of life and perception of dyspnea.

RESULTS

No significant differences in the severity of airway obstruction, perception of dyspnea and quality of life scores were found between the groups. The distance covered on the 6MWT was similar in COPD patients with and without LBM depletion (470.3 +/- 68.5 m vs. 448.2 +/- 89.2 m). However, patients with LBM depletion presented significantly greater differences between baseline and final values in terms of heart rate and Borg scale index for lower limb fatigue. There was a significant positive correlation between distance covered on the 6MWT and FEV1 (r = 0.381, p = 0.01).

CONCLUSIONS

In the patients studied, functional exercise tolerance and quality of life were unaffected by LBM depletion. However, the patients with LBM depletion presented more pronounced lower limb fatigue during the 6MWT, which underscores the importance of the evaluation and treatment of systemic manifestations in COPD patients.

Exercise and muscle dysfunction in COPD: implications for pulmonary rehabilitation

Skeletal muscle dysfunction in COPD (chronic obstructive pulmonary disease) patients, particularly of the quadriceps, is of clinical interest because it not only influences the symptoms that limit exercise, but may also contribute directly to poor exercise performance and health status, increased healthcare utilization, and mortality. Furthermore, unlike the largely irreversible impairment of the COPD lung, skeletal muscles represent a potential site to improve patients' level of function and quality of life. However, despite expanding knowledge of potential contributing factors and greater understanding of molecular mechanisms of muscle wasting, only one intervention has been shown to be effective in reversing COPD muscle dysfunction, namely exercise training. Pulmonary rehabilitation, an intervention based on individually tailored exercise training, has emerged as arguably the most effective non-pharmacological intervention in improving exercise capacity and health status in COPD patients. The present review describes the effects of chronic exercise training on skeletal muscles and, in particular, focuses on the known effects of pulmonary rehabilitation on the quadriceps muscle in COPD. We also describe the current methods to augment the effects of pulmonary rehabilitation and speculate how greater knowledge of the molecular pathways of skeletal muscle wasting may aid the development of novel pharmaceutical agents.