Nutritional status in chronic obstructive pulmonary disease: Role of hypoxia

The Role of Bioactive Small Molecules in COPD Pathogenesis

Chronic obstructive pulmonary disease (COPD) is recognized as a predominant contributor to mortality worldwide, which causes significant burdens to both society and individuals. Given the limited treatment options for COPD, there lies a critical realization: the imperative for expeditious development of novel therapeutic modalities that can effectively alleviate disease progression and enhance the quality of life experienced by COPD patients. Within the intricate field of COPD pathogenesis, an assortment of biologically active small molecules, encompassing small protein molecules and their derivatives, assumes crucial roles through diverse mechanisms. These mechanisms relate to the regulation of redox balance, the inhibition of the release of inflammatory mediators, and the modulation of cellular functions. Therefore, the present article aims to explore and elucidate the distinct roles played by different categories of biologically active small molecules in contributing to the pathogenesis of COPD.

Serum growth differentiation factor 15 as a biomarker for malnutrition in patients with acute exacerbation of chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) is a common respiratory disease that often coexists with malnutrition during acute exacerbation (AECOPD) and significantly affects the prognosis. Previous studies have shown that growth differentiation factor 15 (GDF15) levels promote appetite suppression, weight loss, and muscle weakness, and are markedly high in peripheral blood following inflammatory stimulation. However, it is still unknown whether serum GDF15 levels can be used to predict malnutrition in patients with AECOPD.

Methods

A total of 142 patients admitted to the Department of Respiratory Medicine at Anshun People's Hospital between December 2022 and August 2023 were selected for this study. The participants were divided into two groups: malnutrition group (n = 44) and non-malnutrition group (n = 98) based on a body mass index (BMI) < 18.5 kg/m2, according to the Global Leadership Initiative on Malnutrition (GLIM) criteria. Serum GDF15 levels were measured using the enzyme-linked immunosorbent assay (ELISA) and compared between the two groups. Spearman correlation analysis was used to examine the association between serum GDF15 levels, baseline data, and clinical indicators. Binary logistic regression was used to identify the independent risk factors for AECOPD combined with malnutrition. The predictive value of serum GDF15, albumin (ALB), and a combination of these was evaluated to identify malnutrition in patients with AECOPD using a receiver operating characteristic (ROC) curve.

Results

Serum GDF15 levels in patients with malnutrition and AECOPD were significantly higher than those in patients without malnutrition, whereas the serum ALB levels were significantly lower than those in patients without malnutrition (p < 0.001). Moreover, serum GDF15 levels were negatively correlated with BMI (r = -0.562, p < 0.001), mid-arm circumference (r = -0.505, p < 0.001), calf circumference (r = -0.490, p < 0.001), total protein (r = -0.486, p < 0.001), ALB (r = -0.445, p < 0.001), and prognostic nutritional index (r = -0.276, p = 0.001), and positively correlated with C-reactive protein (r = 0.318, p < 0.001), COPD assessment test score (r = 0.286, p = 0.001), modified medical research council classification (r = 0.310, p < 0.001), and global initiative for chronic obstructive pulmonary disease grade (r = 0.177, p = 0.035). Furthermore, serum GDF15 levels were an independent risk factor for malnutrition in patients with AECOPD (OR = 1.010, 95% CI, 1.003∼1.016). The optimal cut-off value of serum GDF15 level was 1,092.885 pg/mL, with a sensitivity of 65.90% and a specificity of 89.80%, while the serum ALB level was 36.15 g/L, with a sensitivity of 86.40% and a specificity of 65.00%, as well as a combined sensitivity of 84.10% and a specificity of 73.90%. Serum GDF15 and serum ALB levels had a good predictive ability (AUC = 0.856, AUC = 0.887), and the ROC revealed a greater combined prediction value for the two (AUC = 0.935).

Conclusion

Serum GDF15 levels could be used as a potential biomarker in the prediction of malnutrition in patients with AECOPD, offering a guidance for future clinical evaluation of malnutrition.

Pathogenesis of sarcopenia in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a common pulmonary disease characterized by persistent respiratory symptoms and airflow obstruction. In addition to lung diseases, chronic obstructive pulmonary disease (COPD) is often associated with other organ diseases, and sarcopenia is one of the common diseases. In recent years, multiple factors have been proposed to influence muscle dysfunction in COPD patients, including systemic and local inflammation, oxidative stress, hypoxia, hypercapnia, protein synthesis, catabolic imbalance, nutritional changes, disuse, ageing, and the use of medications such as steroids. These factors alone or in combination can lead to a reduction in muscle mass and cross-sectional area, deterioration of muscle bioenergy metabolism, defects in muscle repair and regeneration mechanisms, apoptosis and other anatomical and/or functional pathological changes, resulting in a decrease in the muscle’s ability to work. This article reviews the research progress of possible pathogenesis of sarcopenia in COPD.

The Role of Zinc in the Pathogenesis of Lung Disease

Lung diseases, such as asthma, chronic obstructive pulmonary diseases (COPD), and cystic fibrosis (CF), are among the leading causes of mortality and morbidity globally. They contribute to substantial economic burdens on society and individuals. Currently, only a few treatments are available to slow the development and progression of these diseases. Thus, there is an urgent unmet need to develop effective therapies to improve quality of life and limit healthcare costs. An increasing body of clinical and experimental evidence suggests that altered zinc and its regulatory protein levels in the systemic circulation and in the lungs are associated with these disease’s development and progression. Zinc plays a crucial role in human enzyme activity, making it an essential trace element. As a cofactor in metalloenzymes and metalloproteins, zinc involves a wide range of biological processes, such as gene transcription, translation, phagocytosis, and immunoglobulin and cytokine production in both health and disease. Zinc has gained considerable interest in these lung diseases because of its anti-inflammatory, antioxidant, immune, and metabolic modulatory properties. Here we highlight the role and mechanisms of zinc in the pathogenesis of asthma, COPD, CF, acute respiratory distress syndrome, idiopathic pulmonary fibrosis, and pulmonary hypertension.

Update on the Etiology, Assessment, and Management of COPD Cachexia: Considerations for the Clinician

Cachexia is a commonly observed but frequently neglected extra-pulmonary manifestation in patients with chronic obstructive pulmonary disease (COPD). Cachexia is a multifactorial syndrome characterized by severe loss of body weight, muscle, and fat, as well as increased protein catabolism. COPD cachexia places a high burden on patients (eg, increased mortality risk and disease burden, reduced exercise capacity and quality of life) and the healthcare system (eg, increased number, length, and cost of hospitalizations). The etiology of COPD cachexia involves a complex interplay of non-modifiable and modifiable factors (eg, smoking, hypoxemia, hypercapnia, physical inactivity, energy imbalance, and exacerbations). Addressing these modifiable factors is needed to prevent and treat COPD cachexia. Oral nutritional supplementation combined with exercise training should be the primary multimodal treatment approach. Adding a pharmacological agent might be considered in some, but not all, patients with COPD cachexia. Clinicians and researchers should use longitudinal measures (eg, weight loss, muscle mass loss) instead of cross-sectional measures (eg, low body mass index or fat-free mass index) where possible to evaluate patients with COPD cachexia. Lastly, in future research, more detailed phenotyping of cachectic patients to enable a better comparison of included patients between studies, prospective longitudinal studies, and more focus on the impact of exacerbations and the role of biomarkers in COPD cachexia, are highly recommended.

The adverse impact of cadmium on immune function and lung host defense

Cadmium (Cd) is a transition metal, also referred to as a heavy metal, that is naturally abundant in the earth's crust. It has no known benefit to humans. It is primarily released into our environment through mining and smelting in industrial processes and enters the food chain through uptake by plants from contaminated soil and water. In humans, Cd primarily enters the body through ingestion of foods and cigarette smoke and has an extremely long resident half-life in the body compared to other transition metals. Environmental workplace exposure is also a source through inhalation, although much less common. The principal organs adversely affected by Cd following acute and chronic exposure are the kidneys, bone, vasculature and lung. Cd adversely impacts cell function through changes in gene expression and signal transduction and is recognized as a carcinogen. Despite a substantial body of mechanistic studies in cells and animal models, the overall impact of Cd on innate immune function in humans remains poorly understood. The best evidence is perhaps alteration of reactive oxygen species balance and signaling in cells that regulate innate immunity causing alteration of the inflammatory response that is postulated to contribute to chronic diseases. Epidemiologic studies support this possibility since increased tissue levels in humans are strongly associated with leading chronic diseases including chronic obstructive pulmonary disease (COPD), which will be discussed in depth. Additional studies are required to understand how chronic exposure and accumulation of this leading environmental toxicant in vital organs negatively impact innate immune function and host defense leading to chronic disease in humans.

[Nutritional status and dietary intake in patients with chonic obstructive pulmonary disease]

INTRODUCTION

Undernutrition is a predictor of mortality in chronic obstructive pulmonary disease (COPD). The objectives of our study were to assess nutritional intake in COPD and to study its relationship with disease severity.

METHODS

A cross-sectional study that included 66 patients followed for COPD. Patients included had a body composition study and a respiratory and nutritional assessment.

RESULTS

The mean age of the population was 66±9 years. The lean body mass index (LMI) was reduced in 26.1% of patients. It was significantly associated with the GOLD group (P=0.04) and significantly correlated with the forced expiratory volume in the first second (FEV1) (P=0.02) and the distance covered during the six-minute walk test (TM6) (P=0.01). A significant difference was found between the caloric intakes and the different GOLD groups (P=0.04). Mean intakes of calories (P=0.002; r=0.07), protein (P=0.01; r=0.16), carbohydrates (P=0.02; r=0.2) and iron (P=0.01; r=0.13) were significantly correlated with the TM6 results. Caloric intake was significantly correlated with LMI (P=0.01; r=0.16), body mass index (P=0.04; r=0.12), FEV1 (P=0.04; r=-0.12) and GOLD stage (0.002). Similarly, protein intake was significantly correlated with LMI (P=0.001; r=0.11), body mass index (P=0.02; r=0.16), FEV1(%) (P=0.001; r=-0.16) and GOLD stage (P=0.002).

CONCLUSION

Undernutrition in COPD is caused by decreased food intake and increased resting energy expenditure. Adequate intakes of glucose, protein, fibers, vitamins and zinc are associated with improved ventilatory function.

Mitochondrial DNA mutations contribute to high altitude pulmonary edema via increased oxidative stress and metabolic reprogramming during hypobaric hypoxia

High altitude pulmonary edema (HAPE) is experienced by non-acclimatized sea level individuals on exposure to high altitude hypoxic conditions. Available evidence suggests that genetic factors and perturbed mitochondrial redox status may play an important role in HAPE pathophysiology. However, the precise mechanism has not been fully understood. In the present study, sequencing of mitochondrial DNA (mtDNA) from HAPE subjects and acclimatized controls was performed to identify pathogenic mutations and to determine their role in HAPE. Hypobaric hypoxia induced oxidative stress and metabolic alterations were also assessed in HAPE subjects. mtDNA copy number, mitochondrial oxidative phosphorylation (mtOXPHOS) activity, mitochondrial biogenesis were measured to determine mitochondrial functions. The data revealed that the mutations in Complex I genes affects the secondary structure of protein in HAPE subjects. Further, increased oxidative stress during hypobaric hypoxia, reduced mitochondrial biogenesis and mtOXPHOS activity induced metabolic reprogramming appears to contribute to mitochondrial dysfunctions in HAPE individuals. Haplogroup analysis suggests that mtDNA haplogroup H2a2a1 has potential contribution in the pathobiology of HAPE in lowlanders. This study also suggests contribution of altered mitochondrial functions in HAPE susceptibility.

Muscle mass and function are related to respiratory function in chronic obstructive pulmonary disease

Background: Chronic obstructive pulmonary disease (COPD), as an airway limitation condition, is accompanied by alteration of muscle mass and function. We aimed to determine the relationship between disease severity and body composition, muscle function, and nutritional status in COPD patients. Methods: This cross-sectional study was conducted on 129 COPD participants. Muscle strength, body composition, and calf circumference (CC) were measured using a hydraulic hand dynamometer, bioelectrical impedance analysis (BIA), and a tape measure, respectively. Furthermore, fat-free mass index (FFMI), body mass index (BMI) and muscle mass value were calculated by equations. Forced expiratory volume in one second (FEV1) was assessed as well. Nutritional status was also evaluated by subjective global assessment (SGA) questionnaire. SPSS software (version 21 ) was used, chi-square, fisher's exact test, univariate and multivariate linear regression models were used for statistical analysis. P-values less than 0.05 were considered significant. Results: Based on FEV1 classification, 52.7% of the patients had severe conditions. The reports indicated that the prevalence of low CC was 54.2%, low muscle mass 38.7%, low FFMI 34.8%, low right handgrip strength 61.2% and low left handgrip strength 64.3%. Furthermore, there was an increasing trend based on FEV1 in low CC (p=0.032), low muscle mass (p=0.005), low FFMI (p=0.002), low right handgrip strength (p=0.004) and low left handgrip strength (p=0.014). The results of univariate analysis showed muscle mass (p=0.036), total protein (p=0.043), FFM (p=0.047), FFMI (p=0.007), SGA (p=0.029), right handgrip strength (p=0.004) and left hand grip strength (p=0.023) were associated with FEV1. In addition, the results of multivariate analysis demonstrated low values of FFMI (p=0.005) and right handgrip strength (p=0.042) were the main detrimental factors for FEV1. The results of multivariate analysis were confirmed by stepwise model. Conclusion: Low values of muscle mass and function are prevalent among COPD patients. The present study revealed that low FFMI and handgrip strength were closely related to disease severity.

Long-term Air Pollution Exposure Under European Union Limits and Adolescents' Lung Function: Modifying Effect of Abnormal Weight in the GINIplus and LISA Birth Cohorts

BACKGROUND

Abnormal weights, eg, obesity, has shown a strong modifying effect on the association between air pollution exposure and lung function impairment in adults.

RESEARCH QUESTION

How might weight status modify the effects of long-term air pollution exposure on adolescents' lung function, particularly in areas with pollution levels much lower than the current European Union (EU) air quality standards?

STUDY DESIGN AND METHODS

In this observational study, we investigated 2,224 adolescents from the German Infant Study on the Influence of Nutrition Intervention Plus Environmental and Genetic Influences on Allergy Development and the Influence of Life Style Factors on the Development of the Immune System and Allergies in East and West Germany birth cohorts. Lung function was measured at age 15 years. Underweight, normal weight, and overweight or obese were defined using percentiles of BMI. Average concentrations of air pollution were modelled at residential addresses at four exposure windows between 0 and 15 years. Multivariate linear regression models were fitted by weight group on lung function with exposure at each window or cumulative exposure since birth.

RESULTS

The median air pollution concentrations were half to two-thirds of the EU standards. Significant associations were observed only for individuals who were underweight and overweight or obese. For example, per interquartile range increase in nitrogen dioxide at the 15-year exposure window, FEV₁ declined by -2.9% (95% CI, -5.2% to -0.5%) for the underweight group and -3.4% (95% CI, -5.4% to -1.2%) for the overweight or obese group. Similarly, longer exposure to moderate-level air pollution since birth was associated significantly with lung function impairment for groups with abnormal weight.

INTERPRETATION

Exposure to low to moderate levels of air pollution was associated with lung function impairment for adolescents with abnormal weight. Longer exposure aggravated the adverse effect. Whether a critical exposure window since birth exists warrants further exploration.

Imbalance in zinc homeostasis enhances lung Tissue Loss following cigarette smoke exposure

Cigarette smoke exposure is a major cause of chronic obstructive pulmonary disease. Cadmium is a leading toxic component of cigarette smoke. Cadmium and zinc are highly related metals. Whereas, zinc is an essential metal required for normal health, cadmium is highly toxic. Zrt- and Irt-like protein 8 (ZIP8) is an avid transporter of both zinc and cadmium into cells and is abundantly expressed in the lung of smokers compared to nonsmokers. Our objective was to determine whether disturbed zinc homeostasis through diet or the zinc transporter ZIP8 increase susceptibility to lung damage following prolonged cigarette smoke exposure.

METHODS

Cigarette smoke exposure was evaluated in the lungs of mice subject to insufficient and sufficient zinc intakes, in transgenic ZIP8 overexpressing mice, and a novel myeloid-specific ZIP8 knockout strain.

RESULTS

Moderate depletion of zinc intakes in adult mice resulted in a significant increase in lung cadmium burden and permanent lung tissue loss following prolonged smoke exposure. Overexpression of ZIP8 resulted in increased lung cadmium burden and more extensive lung damage, whereas cigarette smoke exposure in ZIP8 knockout mice resulted in increased lung tissue loss without a change in lung cadmium content, but a decrease in zinc.

CONCLUSIONS

Overall, findings were consistent with past human studies. Imbalance in Zn homeostasis increases susceptibility to permanent lung injury following prolonged cigarette smoke exposure. Based on animal studies, both increased and decreased ZIP8 expression enhanced irreversible tissue damage in response to prolonged tobacco smoke exposure. We believe these findings represent an important advancement in our understanding of how imbalance in zinc homeostasis and cadmium exposure via tobacco smoke may increase susceptibility to smoking-induced lung disease.

Long-term maintenance of nutritional status with ninjinyoueito in terminal patients with chronic respiratory disease: Two case reports

Ninjinyoeito, is a traditional herbal (Kampo) medicine which is administered to patients with debilitating diseases in North-East Asia. Ninjinyoeito has been reported to be effective against loss of physical strength, fatigue and loss of appetite in patients with wasting diseases. The present study described long-term maintenance of body weight with ninjinyoueito in 2 terminal patients with chronic respiratory diseases. The first patient was a 75-year-old with chronic obstructive pulmonary disease (COPD) who took ninjinyoueito for ≥5 years and the second patient was a 72-year-old man with metastatic lung cancer with combined pulmonary fibrosis and emphysema (CPFE) who took ninjinyoueito for ≥1 year. Both of them maintained their physique and nutritional status during the terminal stages of disease and there were no adverse effects observed in these 2 patients which could be attributed to ninjinyoueito. The results suggest that ninjinyoueito may be a supplementary treatment for the maintenance of nutritional status in patients with a chronic respiratory disease accompanied by wasting, such as COPD.

Dietary Patterns and Prevalence of Post-bronchodilator Airway Obstruction in Dairy Farmers Exposed to Organic Dusts

Exposure to organic dusts is an independent causative factor of chronic obstructive pulmonary disease (COPD). Unhealthy dietary patterns have been associated with poor lung function in smokers. This study investigated whether dietary patterns were associated with post-bronchodilator airway obstruction, a hallmark of COPD, in dairy farmers exposed to organic dusts. All subjects were identified by screening programs and patients with airflow obstruction were matched with subjects with normal spirometry. Six groups were compared, defined by their exposures (non-smoking dairy farmers, smokers ≥ 10 pack-years with no occupational exposure, and smoking dairy farmers) and the presence or absence of post-bronchodilator airflow obstruction, resulting in 321 study subjects. The Alternative Healthy Eating Index (AHEI) score was calculated based on an adapted food frequency questionnaire. Mean total AHEI scores were similar in all groups. Comparison between smokers with post-bronchodilator airway obstruction and subjects with post-bronchodilator airway obstruction related to occupational exposure found minimal differences in dietary patterns: dairy farmers had lower scores for the ratio of white to red meat and higher scores for cereal fiber consumption. As in previous studies, smokers with post-bronchodilator airway obstruction exhibited higher lipid intakes and lower carbohydrate intakes than their counterparts with normal spirometry. No evidence of any meaningful difference in dietary patterns was found between subjects with post-bronchodilator airway obstruction detected by screening and healthy controls, either in dairy farmers or in smokers with no occupational exposure.

Quadriceps strength in patients with chronic obstructive pulmonary disease

Background

Skeletal muscle dysfunction is well known in chronic obstructive pulmonary disease (COPD). The muscle strength is altered in various muscles variedly. Lower-limb muscle strength is very important for walking distance. Reduced lower-limb strength can affect the physical quality of life.

Objectives

The aim of the study was to assess and compare the quadriceps strength in COPD patients and age-matched healthy controls and to study the correlation between lung function parameters and the quadriceps strength in patients with COPD.

Methodology

Thirty nonsmoker male patients; thirty nonsmoker female patients with COPD; and sixty age-, BMI-, and gender-matched healthy controls were studied. Quadriceps muscle strength was measured using a quadriceps dynamometer. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV₁), FEF 25-75, and peak expiratory flow rate were measured using Helios 702 Spirometer. The quadriceps muscle strength between the two groups was compared using the unpaired Student's t-test. Correlations between FVC and FEV₁with muscle strength were analyzed using the Pearson's coefficient.

Results

The mean unilateral and bilateral quadriceps strength in both male and female COPD patients was significantly lesser than the healthy controls (P < 0.05). There was a significant positive correlation between muscle strength and FVC and muscle strength and FEV₁in patients with COPD.

Conclusion

The study shows that there is quadriceps weakness in COPD patients, and pulmonary functions have a direct impact on skeletal muscle strength. Identifying those patients who have reduced strength will allow early interventions targeted at improving the quality of life of the patient.

Improvement in Frailty in a Patient With Severe Chronic Obstructive Pulmonary Disease After Ninjin'yoeito Therapy: A Case Report

Frailty is a poor prognostic factor in patients with chronic obstructive pulmonary disease (COPD). Although various studies have assessed the effects of conventional treatment with bronchodilators, nutritional support, and pulmonary rehabilitation for frailty in patients with COPD, none have addressed the effects of traditional Japanese medicine (Kampo medicine). Herein, we report the successful management of frailty using Ninjin'yoeito therapy in a 76-year-old patient with COPD. Despite being prescribed multiple bronchodilators, nutritional supplement therapy, patient education, and pulmonary rehabilitation, the patient exhibited unintentional weight loss, low energy, and low physical activity. Ninjin'yoeito was prescribed and these subjective symptoms began to improve 1 month after treatment initiation. In 6 months, the patient reported no frailty, had increased muscle mass, and had achieved an almost normal healthy state. Ninjin'yoeito has been associated with both physical effects, such as improvement in overall physical strength and appetite, and reduction in fatigue, and psychological effects, such as greater motivation and reduction of depression and anxiety symptoms. Physicians have usually treated COPD primarily with organ-specific treatments, such as bronchodilators; however, addressing both the physiological and psychological vulnerability has been difficult. This case report illustrates the potential usefulness of Ninjin'yoeito treatment for frailty in patients with COPD.

Nutritional status and muscle dysfunction in chronic respiratory diseases: stable phase versus acute exacerbations

Nutritional abnormalities are frequent in different chronic respiratory diseases such as chronic obstructive pulmonary disease (COPD), bronchiectasis, cystic fibrosis (CF), interstitial fibrosis and lung cancer, having important clinical consequences. However, nutritional abnormalities often remained underdiagnosed due to the relative lack of awareness of health professionals. Therefore, systematic anthropometry or even better, assessment of body composition, should be performed in all patients with chronic respiratory conditions, especially following exacerbation periods when malnutrition becomes more accentuated. Nutritional abnormalities very often include the loss of muscle mass, which is an important factor for the occurrence of muscle dysfunction. The latter can be easily detected with the specific assessment of muscle strength and endurance, and also negatively influences patients' quality of life and prognosis. Both nutritional abnormalities and muscle dysfunction result from the interaction of several factors, including tobacco smoking, low physical activity-sedentarism, systemic inflammation and the imbalance between energy supply and requirements, which essentially lead to a negative balance between protein breakdown and synthesis. Therapeutic approaches include improvements in lifestyle, nutritional supplementation and training. Anabolic drugs may be administered in some cases.

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.

A journey between high altitude hypoxia and critical patient hypoxia: What can it teach us about compression and the management of critical disease?

High altitude sickness (hypobaric hypoxia) is a form of cellular hypoxia similar to that suffered by critically ill patients. The study of mountaineers exposed to extreme hypoxia offers the advantage of involving a relatively homogeneous and healthy population compared to those typically found in Intensive Care Units (ICUs), which are heterogeneous and generally less healthy. Knowledge of altitude physiology and pathology allows us to understanding how hypoxia affects critical patients. Comparable changes in mitochondrial biogenesis between both groups may reflect similar adaptive responses and suggest therapeutic interventions based on the protection or stimulation of such mitochondrial biogenesis. Predominance of the homozygous insertion (II) allele of the angiotensin-converting enzyme gene is present in both individuals who perform successful ascensions without oxygen above 8000 m and in critical patients who overcome certain disease conditions.

A minor but deadly surgery of colonic polypectomy in an elderly and fragile patient: a case report and the review of literature

Background

Epithelial dysplasia and adenomatous polyps of colorectum are precancerous lesions. Surgical removal is still one of the important treatment approaches for colorectal polyps.

Case presentation

A male patient over 78 years was admitted due to bloody stool and abdominal pain. Colonoscopic biopsy showed a high-grade epithelial dysplasia in an adenomatous polyp of sigmoid colon. Anemia, COPD, ischemic heart disease (IHD), arrhythmias, and hypoproteinemia were comorbidities. The preoperative preparation was carefully made consisting of oral nutritional supplements (ONS), blood transfusion, cardiorespiratory management, and hemostatic therapy. However, his illness did not improve but deteriorate mainly due to polyp rebleeding during preparative period. The open polypectomy was performed within 60 min under epidural anesthesia. Postoperative treatments included oxygen inhalation, bronchodilation, parenteral and enteral nutrition, human serum albumin, antibiotics, and blood transfusion. Unluckily, these did not significantly facilitate to surgical recovery on account of severe comorbidities and complications. The most serious complications were colonic leakage and secondary abdominal severe infection. The patient finally gave up treatment due to multiple organ dysfunction syndromes.

Conclusions

The polypectomy for colonic polyp is a seemingly minor but potentially deadly surgery for patients with severe comorbidities, and prophylactic ostomy should be considered for the safety.

Cachexia: a nutritional syndrome?

Cachexia leads to nutritional deficits including anorexia and loss of fat and muscle mass. In persons with precachexia or early cachexia, for example, old persons with weight loss and chronic obstructive pulmonary disease, there is strong evidence that nutritional support improves outcomes. Limited evidence suggests that this may be true for heart failure and chronic kidney disease. The evidence for nutritional support in refractory cachexia is, not surprisingly, less dramatic. It would appear that early in the cachectic process, nutrition, coupled with exercise, may be an important therapeutic approach.

Guidelines for the evaluation and treatment of muscle dysfunction in patients with chronic obstructive pulmonary disease

In patients with chronic obstructive pulmonary disease (COPD), skeletal muscle dysfunction is a major comorbidity that negatively impacts their exercise capacity and quality of life. In the current guidelines, the most recent literature on the various aspects of COPD muscle dysfunction has been included. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) scale has been used to make evidence-based recommendations on the different features. Compared to a control population, one third of COPD patients exhibited a 25% decline in quadriceps muscle strength, even at early stages of their disease. Although both respiratory and limb muscles are altered, the latter are usually more severely affected. Numerous factors and biological mechanisms are involved in the etiology of COPD muscle dysfunction. Several tests are proposed in order to diagnose and evaluate the degree of muscle dysfunction of both respiratory and limb muscles (peripheral), as well as to identify the patients' exercise capacity (six-minute walking test and cycloergometry). Currently available therapeutic strategies including the different training modalities and pharmacological and nutritional support are also described.

Prognostic factors for clinical failure of exacerbations in elderly outpatients with moderate-to-severe COPD

Background

Acute exacerbations represent a significant burden for patients with moderate-to-severe chronic obstructive pulmonary disease. Each exacerbation episode is frequently associated with a lengthy recovery and impaired quality of life. Prognostic factors for outpatients that may predict poor outcome after treatment with antibiotics recommended in the guidelines, are not fully understood. We aimed to identify pretherapy factors predictive of clinical failure in elderly (≥60 years old) outpatients with acute Anthonisen type 1 exacerbations.

Trial registration

NCT00656747.

Methods

Based on the moxifloxacin in AECOPDs (acute exacerbations of chronic obstructive pulmonary disease) trial (MAESTRAL) database, this study evaluated pretherapy demographic, clinical, sputum bacteriological factors using multivariate logistic regression analysis, with internal validation by bootstrap replicates, to investigate their possible association with clinical failure at end of therapy (EOT) and 8 weeks posttherapy.

Results

The analyses found that the independent factors predicting clinical failure at EOT were more frequent exacerbations, increased respiratory rate and lower body temperature at exacerbation, treatment with long-acting anticholinergic drugs, and in vitro bacterial resistance to study drug. The independent factors predicting poor outcome at 8 weeks posttherapy included wheezing at preexacerbation, mild or moderate (vs extreme) sleep disturbances, lower body temperature at exacerbation, forced expiratory volume in 1 second <30%, lower body mass index, concomitant systemic corticosteroids for the current exacerbation, maintenance long-acting β₂-agonist and long-acting anticholinergic treatments, and positive sputum culture at EOT.

Conclusion

Several bacteriological, historical, treatment-related factors were identified as predictors of early (EOT) and later (8 weeks posttherapy) clinical failure in this older outpatient population with moderate-to-severe chronic obstructive pulmonary disease. These patients should be closely monitored and sputum cultures considered before and after treatment.

Assessment of energy intake in women with chronic obstructive pulmonary disease: a doubly labeled water method study

OBJECTIVES

To maintain energy balance, reliable methods for assessing energy intake and expenditure should be used in patients with chronic obstructive pulmonary disease (COPD). The purpose of this study was to validate the diet history and 7-day food diary methods of assessing energy intake (EI) using total energy expenditure (TEE) with the doubly labeled water (DLW) method (TEEDLW) as the criterion method in outpatient women with COPD.

METHODS

EI was assessed by diet history (EIDH) and a 7-day food diary (EIFD) in 19 women with COPD, using TEEDLW as the criterion method. The three methods were compared using intra-class correlation coefficients (ICC) and Bland-Altman analyses. The participants were classified according to their reporting status (EI/TEE) as valid-reporters 0.79-1.21, under-reporters < 0.79 or over-reporters > 1.21.

RESULTS

Diet history underestimated reported EI by 28%, and 7-day food diary underestimated EI by approximately 20% compared with TEEDLW. The ICC analysis showed weak agreement between TEEDLW and EIDH (ICC=-0.01; 95%CI-0.10 to 0.17) and between TEEDLW and EIFD (ICC=0.11; 95%CI -0.16 to 0.44). The Bland-Altman plots revealed a slight systematic bias for both methods. For diet history, six women (32%) were identified as valid-reporters, and for the 7-day food diary, twelve women (63%) were identified as valid-reporters. The accuracy of reported EI was only related to BMI.

CONCLUSION

The diet history and 7-day food diary methods underestimated energy intake in women with COPD compared with the DLW method. Individuals with higher BMIs are prone to underreporting. Seven-day food diaries should be used with caution in assessing EI in women with COPD.

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.

Oxidative stress and nutritional status in chronic obstructive pulmonary disease

BACKGROUND

Oxidative stress and malnutrition are shown to have pathogenic effect in Chronic Obstructive Pulmonary Disease (COPD).

AIM

This study was done to assess the burden of oxidative stress in COPD and to determine its relation to their nutritional status.

MATERIALS AND METHODS

In this cross-sectional study, 100 COPD cases from emergency and medical ward and meeting inclusion criteria, along with age, sex and occupation (mainly farmers, housewives and drivers) matched 100 controls without COPD and meeting inclusion criteria were enrolled. Oxidative stress was assessed by measuring lipid peroxidation product, Malondialdehyde (MDA) and antioxidants, like Vitamin C, E and Red Blood Cell Catalase (RBCC). Mini Nutritional Assessment (MNA) tool and Body Mass Index (BMI) were used to assess nutritional status.

STATISTICAL ANALYSIS

Chi-square test was applied for categorical variable. Student t-test was applied for comparison of means. Analysis of Variance (ANOVA) was applied for comparison between groups followed by Bonferroni post hoc analysis. Pearson correlation method was used for quantitative variables. Statistical significance was defined as p< 0.05 (two tailed).

RESULTS

COPD cases had significantly high MDA level with low level of Vitamin E and catalase as compared to controls (p < 0.001). Most of the COPD cases were underweight (BMI ≤ 18.5 Kg/m(2)) and malnourished (MNA score less than 7). Bonferroni post-hoc analysis, showed significantly high burden of oxidative stress in underweight and malnourished cases as compared to normal weight (p < 0.05) among COPD cases. Highly significant correlation was seen between BMI and plasma MDA level (r = -0.27, p = 0.008) in COPD cases.

CONCLUSION

This study shows impaired oxidant/antioxidant balance along with malnutrition and underweight in COPD, which signals for considering antioxidant therapy along with nutritional management.

Anaemia in chronic obstructive pulmonary disease: an insight into its prevalence and pathophysiology

Chronic obstructive pulmonary disease (COPD) is a major health problem, with increasing morbidity and mortality. There is a growing literature regarding the extra-pulmonary manifestations of COPD, which can have a significant impact on symptom burden and disease progression. Anaemia is one of the more recently identified co-morbidities, with a prevalence that varies between 4.9% and 38% depending on patient characteristics and the diagnostic criteria used. Systemic inflammation seems to be an important factor for its establishment and repeated bursts of inflammatory mediators during COPD exacerbations could further inhibit erythropoiesis. However, renal impairment, malnutrition, low testosterone levels, growth hormone level abnormalities, oxygen supplementation, theophylline treatment, inhibition of angiotensin-converting enzyme and aging itself are additional factors that could be associated with the development of anaemia. The present review evaluates the published literature on the prevalence and significance of anaemia in COPD. Moreover, it attempts to elucidate the reasons for the high variability reported and investigates the complex pathophysiology underlying the development of anaemia in these patients.

Acute and chronic effects of atmospheric oxygen on the feeding behavior of Drosophila melanogaster larvae

All insects studied to date show reduced growth rates in hypoxia. Drosophila melanogaster reared in moderate hypoxia (10 kPa PO2) grow more slowly and form smaller adults, but the mechanisms responsible are unclear, as metabolic rates are not oxygen-limited. It has been shown that individual fruit flies do not grow larger in hyperoxia (40 kPa PO2), but populations of flies evolve larger size. Here we studied the effect of acute and chronic variation in atmospheric PO2 (10, 21, 40 kPa) on feeding behavior of third instar larvae of D.melanogaster to assess whether oxygen effects on growth rate can be explained by effects on feeding behavior. Hypoxic-reared larvae grew and developed more slowly, and hyperoxic-rearing did not affect growth rate, maximal larval mass or developmental time. The effect of acute exposure to varying PO2 on larval bite rates matched the pattern observed for growth rates, with a 22% reduction in 10 kPa PO2 and no effect of 40 kPa PO2. Chronic rearing in hypoxia had few effects on the responses of feeding rates to oxygen, but chronic rearing in hyperoxia caused feeding rates to be strongly oxygen-dependent. Hypoxia produced similar reductions in bite rate and in the volume of tunnels excavated by larvae, supporting bite rate as an index of feeding behavior. Overall, our data show that reductions in feeding rate can explain reduced growth rates in moderate hypoxia for Drosophila, contributing to reduced body size, and that larvae cannot successfully compensate for this level of hypoxia with developmental plasticity.

Mid- to late term hypoxia in the mouse alters placental morphology, glucocorticoid regulatory pathways and nutrient transporters in a sex-specific manner

Maternal hypoxia is a common perturbation that can disrupt placental and thus fetal development, contributing to neonatal impairments. Recently, evidence has suggested that physiological outcomes are dependent upon the sex of the fetus, with males more susceptible to hypoxic insults than females. This study investigated the effects of maternal hypoxia during mid- to late gestation on fetal growth and placental development and determined if responses were sex specific. CD1 mice were housed under 21% or 12% oxygen from embryonic day (E) 14.5 until tissue collection at E18.5. Fetuses and placentas were weighed before collection for gene and protein expression and morphological analysis. Hypoxia reduced fetal weight in both sexes at E18.5 by 7% but did not affect placental weight. Hypoxia reduced placental mRNA levels of the mineralocorticoid and glucocorticoid receptors and reduced the gene and protein expression of the glucocorticoid metabolizing enzyme HSD11B2. However, placentas of female fetuses responded differently to maternal hypoxia than did placentas of male fetuses. Notably, morphology was significantly altered in placentas from hypoxic female fetuses, with a reduction in placental labyrinth blood spaces. In addition mRNA expression of Glut1, Igf2 and Igf1r were reduced in placentas of female fetuses only. In summary, maternal hypoxia altered placental formation in a sex specific manner through mechanisms involving placental vascular development, growth factor and nutrient transporter expression and placental glucocorticoid signalling. This study provides insight into how sex differences in offspring disease development may be due to sex specific placental adaptations to maternal insults.

Pulmonary rehabilitation: the reference therapy for undernourished patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) combines the deleterious effects of chronic hypoxia, chronic inflammation, insulin-resistance, increased energy expenditure, muscle wasting, and exercise deconditioning. As for other chronic disorders, loss of fat-free mass decreased survival. The preservation of muscle mass and function, through the protection of the mitochondrial oxidative metabolism, is an important challenge in the management of COPD patients. As the prevalence of the disease is increasing and the medical advances make COPD patients live longer, the prevalence of COPD-associated nutritional disorders is expected to increase in future decades. Androgenopenia is observed in 40% of COPD patients. Due to the stimulating effects of androgens on muscle anabolism, androgenopenia favors loss of muscle mass. Studies have shown that androgen substitution could improve muscle mass in COPD patients, but alone, was insufficient to improve lung function. Two multicentric randomized clinical trials have shown that the association of androgen therapy with physical exercise and oral nutritional supplements containing omega-3 polyinsaturated fatty acids, during at least three months, is associated with an improved clinical outcome and survival. These approaches are optimized in the field of pulmonary rehabilitation which is the reference therapy of COPD-associated undernutrition.

Prognostic factors in patients with terminal stage lung cancer

BACKGROUND

Lung cancer is the leading cause of cancer-related death.(1) Accurate prediction of survival in the terminal stage is important, because it may help patients make a rational decision. Although several prognostic scores have been described as effective indicators of outcome, these scores were intended for patients with other types of cancers. There is no prognostic score for patients with terminal-stage lung cancer.

OBJECTIVE

The aim of this study was to determine prognostic factors for patients with terminal-stage lung cancer.

SETTING/SUBJECTS

Patients in our palliative care unit (PCU) were selected retrospectively and divided into two independent groups, training and testing. Univariate and multivariate analyses were performed on data from the training group to detect independent prognostic factors, while data from patients in the testing group were analyzed to validate whether these prognostic factors predicted near-term death.

RESULTS

Ninety-three patients (69 in the training group and 24 in the testing group) were included in the analyses. Multivariate analysis showed that fatigue, anorexia, desaturation, hyponatremia, and hypoalbuminemia were independent prognostic factors in the training group. Mean survival time in patients who had more than three of these five factors was 9.2±2.6 days (p=0.012). In the testing group, the presence of more than three of these five factors predicted death within two weeks, with a sensitivity of 100% and specificity of 75%.

CONCLUSIONS

This study revealed that fatigue, anorexia, desaturation, hyponatremia, and hypoalbuminemia may be short-term prognostic factors in terminally ill lung cancer patients. In particular, the presence of more than three of these factors predicted death within two weeks.

[Nutritional abnormalities in chronic obstructive pulmonary disease]

Nutritional abnormalities are associated with chronic obstructive pulmonary disease with a frequency ranging from 2 to 50%, depending on the geographical area and the study design. Diagnostic tools include anthropometry, bioelectrical impedance, dual energy radioabsortiometry and deuterium dilution, being the body mass and the lean mass indices the most frequently used parameters. While the most important consequences of nutritional abnormalities are muscle dysfunction and exercise limitation, factors implicated include an imbalance between caloric intake and consumption, and between anabolic and catabolic hormones, inflammation, tobacco smoking, poor physical activity, hypoxemia, some drugs and aging/comorbidities. The most important molecular mechanism for malnutrition associated with chronic obstructive pulmonary disease appears to be the mismatching between protein synthesis and breakdown. Among the therapeutic measures proposed for these nutritional abnormalities are improvements in lifestyle and nutritional support, although the use of anabolic drugs (such as secretagogues of the growth hormone) offers a new therapeutic strategy.

Chronic obstructive pulmonary disease patient journey: hospitalizations as window of opportunity for extra-pulmonary intervention

PURPOSE OF REVIEW

Hospitalizations due to exacerbation of chronic obstructive pulmonary disease (COPD) are a major burden for patient and healthcare system. Extra-pulmonary needs and resulting interventions are poorly investigated.

RECENT FINDINGS

COPD induces nutritional issues, body composition changes and limits patient exercise capacity. The COPD patient journey can be accelerated through exacerbations during which disease-related detrimental factors such as systemic inflammation, hypoxia, inactivity, and glucocorticosteroid treatment converge and intensify, which acutely and often irreversibly worsens patient condition. Specific needs during exacerbations reach beyond the respiratory system, thus clinicians should comprehensively evaluate patients and identify potent and feasible metabolic and anabolic intervention targets. General and specific nutritional support appear feasible and with potential to cover for the changed bodily requirements during exacerbation. Adjunctive physical exercise or neuromuscular electrical stimulation may prevent the muscle loss.

SUMMARY

Hospitalizations should be considered as a window of opportunity for detailed patient assessment and implementation of tailored extra-pulmonary adjunctive strategies with long-term implications. Nutritional assessment and support as well as physical exercise appear promising but should be investigated in adequately designed and conducted trials.

Chronic obstructive pulmonary disease and mortality from pneumonia: meta-analysis

BACKGROUND

We aimed to determine whether patients with concomitant community-acquired pneumonia (CAP) and chronic obstructive pulmonary disease (COPD) are at greater risk of death when compared with those with CAP or acute COPD exacerbation alone. We also assessed the effect of inhaled corticosteroids (ICS) on pneumonia mortality in COPD.

METHODS

We searched MEDLINE and EMBASE from inception to March 2012 for studies reporting on mortality in patients with COPD and CAP. We assessed ascertainment of disease, mortality, drug exposure and adjustment for confounders. Data were pooled using random effects meta-analysis, and heterogeneity was estimated using I².

RESULTS

We identified 24 eligible articles overall. Evaluation of 13 studies revealed considerable heterogeneity and a non-significant mortality risk associated with concomitant COPD and CAP as compared with CAP in five studies that reported adjusted or severity-matched data, pooled RR 1.44 (95% CI 0.97-2.16, I² = 50%). There was also considerable inconsistency amongst the effect estimates from five studies that reported on the associated mortality with concomitant CAP and COPD as compared with acute COPD exacerbations alone. Evaluation of six datasets found that ICS use in COPD was not consistently associated with lower mortality in CAP. Reports of reduced mortality with prior ICS use stemmed from three studies that enrolled participants from the same healthcare database.

CONCLUSIONS

Evidence on associated mortality risk with concomitant CAP and COPD (as opposed to CAP alone, or COPD exacerbation alone) is weak and heterogeneous. ICS use was not consistently associated with reduced mortality from pneumonia.

Distinct responses of protein turnover regulatory pathways in hypoxia- and semistarvation-induced muscle atrophy

The balance of muscle protein synthesis and degradation determines skeletal muscle mass. We hypothesized that hypoxia-induced muscle atrophy and alterations in the regulation of muscle protein turnover include a hypoxia-specific component, in addition to the observed effects of reduction in food intake in response to hypoxia. Mice were subjected to normoxic, hypoxic (8% oxygen), or pair-fed conditions for 2, 4, and 21 days. Cell-autonomous effects of hypoxia on skeletal muscle were also assessed in differentiated C2C12 myotubes. Hypoxia induced an initial rapid loss of body and muscle weight, which remained decreased during chronic hypoxia and could only in part be explained by the hypoxia-induced reduction of food intake (semistarvation). Regulatory steps of protein synthesis (unfolded protein response and mammal target of rapamycin signaling) remained active in response to acute and sustained hypoxia but not to semistarvation. Activation of regulatory signals for protein degradation, including increased expression of Murf1, Atrogin-1, Bnip3, and Map1lc3b mRNAs, was observed in response to acute hypoxia and to a lesser extent following semistarvation. Conversely, the sustained elevation of Atrogin-1, Bnip3, and Map1lc3b mRNAs and the increased activity of their upstream transcriptional regulator Forkhead box O1 were specific to chronic hypoxia because they were not observed in response to reduced food intake. In conclusion, altered regulation of protein turnover during hypoxia-induced muscle atrophy resulted from an interaction of semistarvation and a hypoxia-specific component. The finding that food restriction but not hypoxia-induced semistarvation inhibited regulatory steps in protein synthesis suggests a hypoxia-specific impairment of the coordination between protein-synthesis signaling and protein-degradation signaling in skeletal muscle.

Characterization of the inflammatory and metabolic profile of adipose tissue in a mouse model of chronic hypoxia

In both obesity and chronic obstructive pulmonary disease (COPD), altered oxygen tension in adipose tissue (AT) has been suggested to evoke AT dysfunction, subsequently contributing to metabolic complications. Studying the effects of chronic hypoxia on AT function will add to our understanding of the complex pathophysiology of alterations in AT inflammation, metabolism, and mass observed in both obesity and COPD. This study investigated the inflammatory and metabolic profile of AT after chronic hypoxia. Fifty-two-week-old C57Bl/6J mice were exposed to chronic hypoxia (8% O2) or normoxia for 21 days, after which AT and plasma were collected. Adipocyte size, AT gene expression of inflammatory and metabolic genes, AT macrophage density, and circulating adipokine concentrations were measured. Food intake and body weight decreased upon initiation of hypoxia. However, whereas food intake normalized after 10 days, lower body weight persisted. Chronic hypoxia markedly reduced AT mass and adipocyte size. AT macrophage density and expression of Emr1, Ccl2, Lep, and Tnf were decreased, whereas Serpine1 and Adipoq expression levels were increased after chronic hypoxia. Concomitantly, chronic hypoxia increased AT expression of regulators of oxidative metabolism and markers of mitochondrial function and lipolysis. Circulating IL-6 and PAI-1 concentrations were increased, and leptin concentration was decreased after chronic hypoxia. Chronic hypoxia is associated with decreased rather than increased AT inflammation, and markedly decreased fat mass and adipocyte size. Furthermore, our data indicate that chronic hypoxia is accompanied by significant alterations in AT metabolic gene expression, pointing toward an enhanced AT metabolic rate.

Nutritional status and disease severity in patients with chronic obstructive pulmonary disease (COPD)

The purpose of this study was to identify the relationship between nutritional status and the severity of the disease in patients with COPD in South Korea. This study used pretest data from a larger intervention study. Data were collected from March to October 2010, and 251 patients diagnosed with COPD from five hospitals in South Korea were included in the analysis. All participants were interviewed face-to-face. Actual dietary intake was measured by a 24-h dietary recall, and the body mass index (BMI), obstruction of the airway (FEV1% predicted), degree of dyspnea (modified Medical Research Council: MMRC), and exercise capacity (6min walking distance: 6MWD) (BODE) index was calculated to estimate the severity of the condition. Lower BODE index scores indicate lower risk of mortality. The data were analyzed by descriptive statistics, a χ(2) test, t-tests, analysis of variance (ANOVA), Pearson correlation, and hierarchical multiple regression using SPSS 18.0. The mean age of the participants was 66.83 years and 92.4% of the participants were men. The mean total energy intake was 1431.65kcal, and the mean BODE index score was 2.89. Total energy intake significantly explained additional variance in BODE, BMI, the severity of the perceived dyspnea, and the length of 6min walk after controlling for age, duration after diagnosed with COPD, and physical activities. The findings of this study emphasized the importance of calorie intake in the disease severity among COPD patients. Further research on the effects of nutritional intervention on the health outcomes of patients with COPD is warranted.

Chronic obstructive pulmonary disease and comorbidities

Results of epidemiological studies have shown that chronic obstructive pulmonary disease (COPD) is frequently associated with comorbidities, the most serious and prevalent being cardiovascular disease, lung cancer, osteoporosis, muscle weakness, and cachexia. Mechanistically, environmental risk factors such as smoking, unhealthy diet, exacerbations, and physical inactivity or inherent factors such as genetic background and ageing contribute to this association. No convincing evidence has been provided to suggest that treatment of COPD would reduce comorbidities, although some indirect indications are available. Clear evidence that treatment of comorbidities improves COPD is also lacking, although observational studies would suggest such an effect for statins, β blockers, and angiotensin-converting enzyme blockers and receptor antagonists. Large-scale prospective studies are needed. Reduction of common risk factors seems to be the most powerful approach to reduce comorbidities. Whether reduction of so-called spill-over of local inflammation from the lungs or systemic inflammation with inhaled or systemic anti-inflammatory drugs, respectively, would also reduce COPD-related comorbidities is doubtful.

Circulatory and Adipose Tissue Leptin and Adiponectin in Relationship to Resting Energy Expenditure in Patients With Chronic Obstructive Pulmonary Disease

Increases in resting energy expenditure (REE) likely contribute to weight loss in various chronic diseases. In chronic obstructive pulmonary disease (COPD), relationships between the ventilatory impairment and increased REE, and between disturbances in adipokines and weight loss were previously described. Therefore, we investigated serum levels and adipose tissue expression of leptin and adiponectin, and their relationships to REE in patients with COPD. In 44 patients with stable COPD (38 male; age 62.3±7.2 years), REE was assessed using indirect calorimetry. Subcutaneous adipose tissue samples were analyzed using real-time PCR. From underweight [n=9; body mass index (BMI) <20.0 kg.m−2], to normal weight-overweight (n=24, BMI=20.0-29.9 kg.m−2) and obese patients (n=11; BMI≥30 kg.m−2), REE adjusted for body weight decreased (32.9±6.1 vs. 26.2±5.8 vs. 23.9±6.6 kcal.kg−1.24 h−1, p=0.006), serum levels and adipose tissue expression of leptin increased (p<0.001 for both), and serum and adipose tissue adiponectin decreased (p<0.001; p=0.004, respectively). REE was inversely related to serum and adipose tissue leptin (R=−0.547, p<0.001; R=−0.458, p=0.002), and directly to serum adiponectin (R=0.316, p=0.039). Underweight patients had increased REE compared to normal weight-overweight patients, in association with reductions in serum and adipose tissue leptin, and increased serum adiponectin, suggesting a role of adipokines in energy imbalance in COPD-related cachexia.

Intake of ruminant trans fatty acids and changes in body weight and waist circumference

BACKGROUND/OBJECTIVES

Follow-up studies have suggested that total intake of trans fatty acids (TFA) is a risk factor for gain in body weight and waist circumference (WC). However, in a cross-sectional study individual TFA isomers in adipose tissue had divergent associations with anthropometry. Our objective was to investigate the association between intake of TFA from ruminant dairy and meat products and subsequent changes in weight and WC. Furthermore, potential effect modification by sex, age, body mass index and WC at baseline was investigated.

SUBJECTS/METHODS

Data on weight, WC, habitual diet and lifestyle were collected at baseline in a Danish cohort of 30,851 men and women aged 50-64 years. Follow-up information on weight and WC was collected 5 years after enrolment. The associations between intake of ruminant TFA (R-TFA) and changes in weight and WC were analysed using multiple linear regression with cubic spline modelling.

RESULTS

Intake of R-TFA, both absolute and energy-adjusted intake, was significantly associated with weight change. Inverse associations were observed at lower intakes with a levelling-off at intakes >1.2 g/day and 0.4 energy percentage (E %). Absolute, but not energy-adjusted, intake of R-TFA was significantly associated with WC change. An inverse association was observed at lower intakes with a plateau above an intake of 1.2 g/day.

CONCLUSIONS

The present study suggests that intake of R-TFA is weakly inversely associated with changes in weight, whereas no substantial association with changes in WC was found.

Role of mtDNA haplogroups in COPD susceptibility in a southwestern Han Chinese population

The interplay of a complex genetic basis with the environmental factors of chronic obstructive pulmonary disease (COPD) may account for the differences in individual susceptibility to COPD. Mitochondrial DNA (mtDNA) contributes to an individual's ability to resist oxidation, an important determinant that affects COPD susceptibility. To investigate whether mtDNA haplogroups play important roles in COPD susceptibility, the frequencies of mtDNA haplogroups and an 822-bp mtDNA deletion in 671 COPD patients and 724 control individuals from southwestern China were compared. Multivariate logistic regression analysis revealed that, whereas mtDNA haplogroups A and M7 might be associated with an increased risk for COPD (OR=1.996, 95% CI=1.149-2.831, p=0.006, and OR=1.754, 95% CI=1.931-2.552, p=0.021, respectively), haplogroups F, D, and M9 might be associated with a decreased risk for COPD in this population (OR=0.554, 95% CI=0.390-0.787, p=0.001; OR=0.758, 95% CI=0.407-0.965, p=0.002; and OR=0.186, 95% CI=0.039-0.881, p=0.034, respectively). Additionally, the increased frequency of the 822-bp mtDNA deletion in male cigarette-smoking subjects among COPD patients and controls of haplogroup D indicated that haplogroup D might increase an individual's susceptibility to DNA damage from external reactive oxygen species derived from heavy cigarette smoking. We conclude that haplogroups A and M7 might be risk factors for COPD, whereas haplogroups D, F, and M9 might decrease the COPD risk in this Han Chinese population.

Cadmium-mediated toxicity of lung epithelia is enhanced through NF-κB-mediated transcriptional activation of the human zinc transporter ZIP8

Cadmium (Cd), a toxic heavy metal and carcinogen that is abundantly present in cigarette smoke, is a cause of smoking-induced lung disease. SLC39A8 (ZIP8), a zinc transporter, is a major portal for Cd uptake into cells. We have recently identified that ZIP8 expression is under the transcriptional control of the NF-κB pathway. On the basis of this, we hypothesized that cigarette-smoke induced inflammation would increase ZIP8 expression in lung epithelia, thereby enhancing Cd uptake and cell toxicity. Herein we report that ZIP8 is a central mediator of Cd-mediated toxicity. TNF-α treatment of primary human lung epithelia and A549 cells induced ZIP8 expression, resulting in significantly higher cell death attributable to both apoptosis and necrosis following Cd exposure. Inhibition of the NF-κB pathway and ZIP8 expression significantly reduced cell toxicity. Zinc (Zn), a known cytoprotectant, prevented Cd-mediated cell toxicity via ZIP8 uptake. Consistent with cell culture findings, a significant increase in ZIP8 mRNA and protein expression was observed in the lung of chronic smokers compared with nonsmokers. From these studies, we conclude that ZIP8 expression is induced in lung epithelia in an NF-κB-dependent manner, thereby resulting in increased cell death in the presence of Cd. From this we contend that ZIP8 plays a critical role at the interface between micronutrient (Zn) metabolism and toxic metal exposure (Cd) in the lung microenvironment following cigarette smoke exposure. Furthermore, dietary Zn intake, or a lack thereof, may be a contributing factor in smoking-induced lung disease.

Molecular mechanisms of cachexia in chronic disease

Cachexia is a metabolic syndrome that manifests with excessive weight loss and disproportionate muscle wasting. It is related to many different chronic diseases, such as cancer, infections, liver disease, inflammatory bowel disease, cardiac disease, chronic obstructive pulmonary disease, chronic renal failure and rheumatoid arthritis. Cachexia is linked with poor outcome for the patients. In this article, we explore the role of the hypothalamus, liver, muscle tissue and adipose tissue in the pathogenesis of this syndrome, particularly concentrating on the role of cytokines, hormones and cell energy-controlling pathways (such as AMPK, PI3K/Akt and mTOR). We also look at possible future directions for therapeutic strategies.