Anthropometric and pulmonary function test profiles of outpatients with stable chronic obstructive pulmonary disease

Preoperative DLco and FEV1 are correlated with postoperative pulmonary complications in patients after esophagectomy

Limited information is available regarding the association between preoperative lung function and postoperative pulmonary complications (PPCs) in patients with esophageal cancer who undergo esophagectomy. This is a retrospective cohort study. Patients were classified into low and high lung function groups by the cutoff of the lowest fifth quintile of forced expiratory volume in 1 s (FEV1) %predicted (%pred) and diffusing capacity of the carbon monoxide (DLco) %pred. The PPCs compromised of atelectasis requiring bronchoscopic intervention, pneumonia, and acute lung injury/acute respiratory distress syndrome. Modified multivariable-adjusted Poisson regression model using robust error variances and inverse probability treatment weighting (IPTW) were used to assess the relative risk (RR) for the PPCs. A joint effect model considered FEV1%pred and DLco %pred together for the estimation of RR for the PPCs. Of 810 patients with esophageal cancer who underwent esophagectomy, 159 (19.6%) developed PPCs. The adjusted RR for PPCs in the low FEV1 group relative to high FEV1 group was 1.48 (95% confidence interval [CI] = 1.09-2.00) and 1.98 (95% CI = 1.46-2.68) in the low DLco group relative to the high DLco group. A joint effect model showed adjusted RR of PPCs was highest in patients with low DLco and low FEV1 followed by low DLco and high FEV1, high DLco and low FEV1, and high DLco and high FEV1 (Reference). Results were consistent with the IPTW. Reduced preoperative lung function (FEV1 and DLco) is associated with post-esophagectomy PPCs. The risk was further strengthened when both values decreased together.

Combined Effect of Early Nutrition Therapy and Rehabilitation for Patients with Chronic Obstructive Pulmonary Disease Exacerbation: A Prospective Randomized Controlled Trial

The effectiveness of rehabilitation programs (RP) for chronic obstructive pulmonary disease (COPD) exacerbation remains controversial. However, few studies have investigated the combined effects of exercise and nutritional therapy. This study aimed to determine the effects of combined nutritional therapy on the physical function and nutritional status of patients with COPD exacerbation who underwent early RP. A randomized controlled trial was conducted in patients hospitalized for COPD exacerbations. Patients were assigned to receive a regular diet in addition to RP (control group) or RP and nutrition therapy (intervention group). Physical function, including quadricep strength and body composition, was assessed. The intervention group was administered protein-rich oral nutritional supplements. A total of 38 patients with negligible baseline differences were included in the analysis. The intervention group showed a notably greater change in quadriceps strength. Lean body mass and skeletal muscle indices markedly decreased in the control group but were maintained in the intervention group. Logistic regression analysis identified nutritional therapy as a significant factor associated with increased muscle strength. No serious adverse events were observed in either group. Therefore, nutritional therapy combined with RP is safe and effective for improving exercise function while maintaining body composition in patients with COPD exacerbation.

Optimizing Nutrition Assessment to Create Better Outcomes in Lung Transplant Recipients: A Review of Current Practices

Lung transplantation offers patients with end-stage lung disease an opportunity for a better quality of life, but with limited organ availability it is paramount that selected patients have the best opportunity for successful outcomes. Nutrition plays a central role in post-surgical outcomes and, historically, body mass index (BMI) has been used as the de facto method of assessing a lung transplant candidate’s nutritional status. Here, we review the historical origins of BMI in lung transplantation, summarize the current BMI literature, and review studies of alternative/complementary body composition assessment tools, including lean psoas area, creatinine-height index, leptin, and dual x-ray absorptiometry. These body composition measures quantify lean body mass versus fat mass and may provide a more comprehensive analysis of a patient’s nutritional state than BMI alone.

Add-on interventions during pulmonary rehabilitation

Both pulmonary rehabilitation (PR) and chronic obstructive pulmonary disease (COPD) are generic terms and it increasingly becomes clear that rehabilitation programmes need to be tailored to the complexity and circumstances of the individual patient. Indeed, PR is described as a comprehensive, individualized intervention based on thorough assessment of identifiable treatable traits. The current review summarizes ongoing developments regarding additional interventions and tools to facilitate PR and improve outcomes in patients with a chronic respiratory disease.

Effects of acupuncture on nutritional state of patients with stable chronic obstructive pulmonary disease (COPD): re-analysis of COPD acupuncture trial, a randomized controlled trial

BACKGROUND

There are an increasing number of evidences that chronic obstructive pulmonary disease (COPD) is a systemic illness and that bodyweight loss is its prominent manifestation. We focused on the nutritional outcomes to find out the effectiveness of acupuncture on nutritional state of COPD patients and on their prognosis in our previous interventional study.

METHODS

The present study is re-analysis of our previous interventional study, COPD Acupuncture Trial (CAT) published in 2012. Data from CAT was re-analyzed in terms of nutritional status, inflammatory biomarkers, and prognostic index. Nutritional states were evaluated by the measurements of body weight, body composition, and muscle strength, and the nutritional hematological examination results (retinol-binding protein (RBP), prealbumin (PA), transferrin (Tf), and hemoglobin (Hb) in serum), and inflammation biomarkers such as carboxyhemoglobin (COHb), High sensitivity C-reactive protein (Hs-CRP), Tumor Necrosis Factor-alpha (TNF-α), Interleukin 6 (IL-6), and Serum Amyloid A (SAA) were measured. The BODE index was measured in terms of prognosis. These measurements were compared between the real acupuncture group (RAG) and the placebo acupuncture group (PAG). All data are presented as mean (SD) or mean (95% CI). The difference between baseline and final volumes was compared using analysis of covariance (ANCOVA). Moreover, correlations between nutritional hematological examination scores and inflammation biomarker parameters were assessed using Spearman's rank correlation coefficient.

RESULTS

After 12 weeks, the change in body weight was significantly greater in the RAG compared with the PAG (mean [SD] difference from baseline: 2.5 [0.4] in RAG vs - 0.5 [1.4] in PAG; mean difference between the groups: 3.00, 95% CI, 2.00 to 4.00 with ANCOVA). Patients in RAG also had improvements in the results of nutritional hematological examination (RBP, PA, Tf, Hb), Inflammation biomarkers (TNF-α, IL-6, SAA, Hs-CRP, COHb) and the BODE index.

CONCLUSION

This study demonstrated some clear evidences that acupuncture can be a useful adjunctive therapy to improve nutritional state of COPD patients.

TRIAL REGISTRATION

UMIN Clinical Trials Registry ( UMIN000001277 ). Retrospectively registered.

Current Nutrition Practices in Adult Lung Transplantation

Nutrition therapy is vital to the overall management of lung transplant recipients. The objective of this review is to outline the current applications of pre- and posttransplant nutrition management of the adult lung transplant recipient. Pretransplant nutrition therapy decisions are based on cause of end-stage lung disease, transplant indications, and pretransplant nutritional status. Maintaining adequate nutrient stores is the major goal of nutrition therapy for patients awaiting transplantation. In the posttransplant course, several gastrointestinal (GI) complications such as gastroesophageal reflux, gastroparesis, and distal intestinal obstruction syndrome complicate nutritional recovery. Long-term nutrition therapy for lung transplant recipients is aimed at management of common comorbid conditions such as obesity, diabetes mellitus, hypertension, osteoporosis, and hyperlipidemia. Lung transplantation outcomes are steadily improving; however, much has yet to be explored to improve the nutrition management of these patients in both the pre- and posttransplantation course.

Associations between the distance covered in the incremental shuttle walk test and lung function and health status in patients with chronic obstructive pulmonary disease

BACKGROUND

Field walk tests such as the incremental shuttle walk test (ISWT) are simple tests for assessing the degree of disability in individuals with chronic obstructive pulmonary disease (COPD). In the present study, the correlations between exercise performance in the ISWT, lung function, and health status were examined in patients with COPD of varying severities.

METHODS

A retrospective examination of 277 COPD patients was performed using the ISWT and lung function tests along with assessment of health status using St. George׳s Respiratory Questionnaire (SGRQ). In addition, we assessed the correlations between the walking distance, lung function parameters, and SGRQ scores.

RESULTS

ISWT distances were poorly correlated with lung function parameters and SGRQ scores in mild COPD patients. In contrast, ISWT distances were significantly correlated with pulmonary function parameters, such as vital capacity (%predicted) and forced expiratory volume in one second, and SGRQ scores in moderate and severe COPD patients.

CONCLUSIONS

The ISWT is more independent of health status and pulmonary function in patients with mild COPD compared to moderate or severe cases. Therefore, the exercise capacity of patients with mild COPD should be estimated by the ISWT.

Management of chronic obstructive pulmonary disease beyond the lungs

Chronic obstructive pulmonary disease (COPD) is an umbrella term that covers many clinical subtypes with clearly different pulmonary and extra-pulmonary characteristics, but with persistent airflow limitation in common. This insight has led to the development of a more personalised approach in bronchodilator therapy, prevention of exacerbations, and advanced treatments (such as non-invasive ventilation and lung volume reduction techniques). However, systemic manifestations and comorbidities of COPD also contribute to different clinical phenotypes and warrant an individualised approach as part of integrated disease management. Alterations in bodyweight and composition, from cachexia to obesity, demand specific management. Psychological symptoms are highly prevalent, and thorough diagnosis and treatment are necessary. Moreover, prevention of exacerbations requires interventions beyond the lungs, including treatment of gastro-oesophageal reflux disease, reduction of cardiovascular risks, and management of dyspnoea and anxiety. In this Review, we discuss the management of COPD beyond the respiratory system and propose treatment strategies on the basis of the latest research and best practices.

Conflicting role of sarcopenia and obesity in male patients with chronic obstructive pulmonary disease: Korean National Health and Nutrition Examination Survey

OBJECTIVE

To determine the impact of sarcopenia and obesity on pulmonary function and quality of life (QOL) in chronic obstructive pulmonary disease (COPD) patients.

RESEARCH DESIGN AND METHODS

Data were obtained from the Korea National Health and Nutrition Examination Survey, including data from health interviews, health examinations, nutritional questionnaires, and laboratory findings. Laboratory data included pulmonary function assessment and dual energy X-ray absorptiometry results. Sarcopenia was measured by dual energy X-ray absorptiometry, and obesity was defined by body mass index. Male COPD patients were then classified into 4 groups according to the presence of sarcopenia and obesity.

RESULTS

In male patients with COPD, the prevalence of sarcopenia was found to be 29.3%, and that of sarcopenic obesity was 14.2%. Furthermore, 22.5% of the patients observed in this study had impaired QOL. Following multivariable statistical analysis, both sarcopenia and obesity were independent risk factors for worsening lung function. Adjusted values of forced vital capacity and forced expiratory volume in 1 second were the lowest in the sarcopenic obesity group. Sarcopenia was also associated with more subjective activity limitation and poorer QOL; however obesity was related to less subjective limitation and better QOL after multivariable analysis. Adjusted value of QOL was the lowest in sarcopenic subjects without obesity, and the highest in obese subject without sarcopenia.

CONCLUSIONS

Both sarcopenia and obesity were found to be associated with worsening lung function in male COPD patients. However, obesity was positively correlated with improved QOL while sarcopenia was negatively correlated with QQL.

Body composition in patients with stable chronic obstructive pulmonary disease: comparison with malnutrition in healthy smokers

OBJECTIVE

Although malnutrition (body mass index (BMI)<18.5kg/ m(2)) has been associated with impaired health status in patients with chronic obstructive pulmonary disease (COPD), the effects of body composition (body fat and protein percentage) in patients with COPD have not been clearly demonstrated.

MATERIALS AND METHODS

A total of 180 stable patients with COPD at the stages of moderate, severe, very severe, and 50 healthy subjects were included in this prospective study. All subjects underwent a clinical evaluation, spirometry tests, anthropometric measurements and blood analysis.

RESULTS

Frequency of underweight was higher in COPD (11.7%) patients than the control group (8%). The frequency of underweight increased as the severity of COPD worsens. There was body decomposition (protein or fat depletion) in not only all underweight patients but also some normal/overweight COPD patients, as well as in the healthy subjects. Deterioration in FEV1 (L), and FEV1/FVC was more evident in underweight patients with protein and fat depletion compared to normal/overweight patients (p=0.004, and p=0.005). Inspiratory and expiratory respiratory muscle power was lower in under-weight patients with depletion than in normal/overweight patients (p=0.02, and p=0.01). DLCO and DLCO/VA were significantly lower in underweight patients than in normal/overweight patients (p=0.003, and p=0.004), they were also lower in normal/overweight patients with depletion than in normal/overweight patients with no depletion (p=0.01, and p=0.07). Normal/overweight patients with protein depletion had the most frequent number of exacerbations than others (p=0.04).

CONCLUSION

These results show that the body decomposition is important in patients with COPD. Assessment of body composition should be a part of nutritional assessment besides BMI in patients with COPD.

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.

Nutritional supplementation for stable chronic obstructive pulmonary disease

BACKGROUND

Individuals with chronic obstructive pulmonary disease (COPD) and low body weight have impaired pulmonary status, reduced diaphragmatic mass, lower exercise capacity and higher mortality than those who are adequately nourished. Nutritional support may be useful for their comprehensive care.

OBJECTIVES

To assess the impact of nutritional support on anthropometric measures, pulmonary function, respiratory and peripheral muscles strength, endurance, functional exercise capacity and health-related quality of life (HRQoL) in COPD.If benefit is demonstrated, to perform subgroup analysis to identify treatment regimens and subpopulations that demonstrate the greatest benefits.

SEARCH METHODS

We identified randomised controlled trials (RCTs) from the Cochrane Airways Review Group Trials Register, a handsearch of abstracts presented at international meetings and consultation with experts. Searches are current to April 2012.

SELECTION CRITERIA

Two review authors independently selected trials for inclusion, assessed risk of bias and extracted the data. Decisions were made by consensus.

DATA COLLECTION AND ANALYSIS

We used post-treatment values when pooling the data for all outcomes, and change from baseline scores for primary outcomes. We used mean difference (MD) to pool data from studies that measured outcomes with the same measurement tool and standardised mean difference (SMD) when the outcomes were similar but the measurement tools different. We contacted authors of the primary studies for missing data.We established clinical homogeneity prior to pooling. We presented the results with 95% confidence intervals (CI) in the text and in a 'Summary of findings' table.

MAIN RESULTS

We included 17 studies (632 participants) of at least two weeks of nutritional support. There was moderate-quality evidence (14 RCTs, 512 participants, nourished and undernourished) of no significant difference in final weight between those who received supplementation and those who did not (MD 0.69 kg; 95% CI -0.86 to 2.24). Pooled data from 11 RCTs (325 undernourished patients) found a statistically significant weight gain (MD 1.65 kg; 95% CI 0.14 to 3.16) in favour of supplementation; three RCTs (116 mixed population) found no significant difference between groups (MD -1.28 kg; 95% CI -6.27 to 3.72). However, when analysed as change from baseline, there was significant improvement with supplementation: 14 RCTs (five of which had imputed SE), MD 1.62 kg (95% CI 1.27 to 1.96 ); 11 RCTs (malnourished), MD 1.73 kg (95% CI 1.29 to 2.17) and three RCTs (mixed), MD 1.44 kg (95% CI 0.68 to 2.19).There was low-quality evidence from five RCTs (six comparisons, 287 participants) supporting a significant improvement from baseline for fat-free mass/fat-free mass index (SMD 0.57; 95% CI 0.04 to 1.09), which was larger for undernourished patients (three RCTs, 125 participants; SMD 1.08; 95% CI 0.70 to 1.47). There was no significant change from baseline noted for adequately nourished patients (one RCT, 71 participants; SMD 0.27; 95% CI -0.20 to 0.73), or for a mixed population (two RCTs, 91 participants; SMD -0.05; 95% CI -0.76 to 0.65).There was moderate-quality evidence from two RCTs (91 mixed participants) that nutritional supplementation significantly improved fat mass/fat mass index from baseline (SMD 0.90; 95% CI 0.46 to 1.33).There was low-quality evidence (eight RCTs, 294 participants) of an increase in mid-arm muscle circumference change (MAMC; MD 0.29; 95% CI 0.02 to 0.57).There was low-quality evidence (six RCTs, 125 participants) of no significant difference in change from baseline scores for triceps measures (MD 0.54; 95% CI -0.16 to 1.24).There was low-quality evidence (five RCTs, 142 participants) of no significant difference between groups in the six-minute walk distance (MD 14.05 m; 95% CI -24.75 to 52.84), 12-minute walk distance or in shuttle walking. However, the pooled change from baseline for the six-minute walk distance was significant (MD 39.96 m; 95% CI 22.66 to 57.26).There was low-quality evidence (seven RCTs, 228 participants) that there was no significant difference between groups in the forced expiratory volume in one second (FEV(1); SMD -0.01; 95% CI -0.31 to 0.30) when measured in litres or percentage predicted.There was low-quality evidence (nine RCTs, 245 participants) of no significant between group difference in maximum inspiratory pressure (MIP; MD 3.54 cm H(2)O; 95% CI -0.90 to 7.99), but those who received supplementation had a higher maximum expiratory pressure (MEP; MD 9.55 cm H(2)O; 95% CI 2.43 to 16.68). For malnourished patients (seven RCTs, 189 participants), those with supplementation had significantly better MIP (MD 5.02; 95% CI 0.29 to 9.76) and MEP (MD 12.73; 95% CI 4.91 to 20.55).There was low-quality evidence (four RCTs, 130 participants) of no significant difference in HRQoL total score (SMD -0.36; 95% CI -0.77 to 0.06) when pooling results from both the St George's Respiratory Questionnaire (SGRQ) and the Chronic Respiratory Questionnaire (CRQ).Two trials (67 participants) used the SGRQ to measure individual domains of activity, impact and symptoms. At the end of treatment, the pooled total SGRQ score was both statistically and clinically significant (MD -6.55; 95% CI -11.7 to -1.41). The three RCTs (123 participants) that used the CRQ to measure the change in individual domains (dyspnoea, fatigue, emotion, mastery), found no significant difference between groups.

AUTHORS' CONCLUSIONS

We found moderate-quality evidence that nutritional supplementation promotes significant weight gain among patients with COPD, especially if malnourished. Nourished patients may not respond to the same degree to supplemental feeding. We also found a significant change from baseline in fat-free mass index/fat-free mass, fat mass/fat mass index, MAMC (as a measure of lean body mass), six-minute walk test and a significant improvement in skinfold thickness (as measure of fat mass, end score) for all patients. In addition, there were significant improvements in respiratory muscle strength (MIP and MEP) and overall HRQoL as measured by SGRQ in malnourished patients with COPD.These results differ from previous reviews and should be considered in the management of malnourished patients with COPD.

The relationships of serum prealbumin levels with parameters that indicate severity of disease and emphysema pattern in patients with stable chronic obstructive pulmonary disease

OBJECTIVE

Malnutrition, which is a complication frequently observed in chronic obstructive pulmonary disease (COPD) and negatively affects prognosis, has become a parameter that must be monitored. Even though various methods are applied to assess malnutrition, biochemical parameters, especially serum prealbumin levels, are useful.

MATERIALS AND METHODS

The relationships between serum prealbumin levels, which we used as an indicator of malnutrition, with the severity of disease and the parameters predicting emphysema in stable COPD patients with no additional health problems were determined in this prospective study.

RESULTS

One hundred stable COPD patients were evaluated prospectively. Serum prealbumin levels had a negative correlation with the total number of hospitalizations due to acute exacerbation, total hospitalization time, and average number of annual hospitalizations, whereas it showed a positive correlation with FEV1 and FEV1/FVC% values. Serum prealbumin levels were positively correlated with the length of the line connecting the costophrenic sinus to the dome of the diaphragm, which is used to assess the presence of emphysema and was negatively correlated with retrosternal distance. Also, in COPD patients with low prealbumin levels, while the FEV1 and FEV1/FVC% values and the length of the line connecting the costophrenic sinus to the diaphragm dome significantly decreased, the retrosternal distance dramatically increased compared to COPD patients with normal prealbumin levels.

CONCLUSION

Serum prealbumin levels were convenient for monitoring malnutrition in COPD, were correlated with spirometric and anamnestic data indicating the severity of COPD, and were useful in distinguishing the subtype of COPD due to its decrease in the presence of emphysema.

Management of dyspnea in patients with chronic obstructive pulmonary disease

A progressive and debilitating illness, chronic obstructive pulmonary disease (COPD) has major worldwide impact. In addition to the care for underlying causes of disease, COPD treatment involves palliative intervention to address associated symptoms; in later stages of disease, when the underlying disease has been maximally treated, symptom management assumes primacy as the goal of care. Dyspnea is the most distressing symptom experienced by COPD patients. When dyspnea cannot be relieved by traditional COPD management strategies (i.e., "refractory dyspnea"), the goal of care shifts from prolonged survival to minimized symptoms, improved function, and enhanced quality of life. Numerous pharmacologic and non-pharmacologic interventions are available to achieve these goals, but supporting evidence is variable. This review summarizes options for managing refractory dyspnea in COPD patients, referring to the available evidence and highlighting areas for further investigation. Topics include oxygen, opioids, psychotropic drugs, inhaled frusemide, Heliox28, nutrition, psychosocial support, and breathing techniques.

Study of the burden on patients with chronic obstructive pulmonary disease

BACKGROUND

Health-related quality of life measures are widely used in patients with chronic obstructive pulmonary disease (COPD). However, they are extremely limited when used to evaluate patients outside the clinical trials. The aim of this study was to analyse the burden of the disease using a simple, validated, self-administered questionnaire specifically developed for patients in daily clinical practice.

METHODS

A total of 3935 patients (74.5% men; mean age, 67 years) participated in a cross-sectional study. The burden of COPD on patients was measured using the Clinical COPD Questionnaire (CCQ). COPD was rated at four levels by the forced expiratory volume in one second (FEV(1)) according to The Global Initiative for Chronic Obstructive Lung Disease (GOLD) scale.

RESULTS

The disease mainly affects old men (more than 50% were over 65 years of age) and non-employed men (23% were employed). Of the patients studied, 22.7% continued smoking, especially men (24.4% of men vs. 18.1% of women). Most patients (54%) were diagnosed with moderate stage II COPD. Severity of COPD was lower in women: 29.6% of men had severe COPD compared with 13.7% of women. During the last year, 65.1% had at least one acute exacerbation and 36.6% were admitted to hospital because of COPD exacerbation. No association was found between the body mass index and COPD stage. The variable that most influenced the disease burden was dyspnoea, as progression from grade 0 to grade 4 increased the disease burden by 1.78 points for symptoms, 2.43 for functional state and 1.53 for mental state. The functional classification of COPD also had a significant influence on the disease burden.

CONCLUSIONS

The present findings show that dyspnoea and the degree of airflow limitation are the clinical variables that most affect the burden of COPD from the patient's point of view.

COPD as a lung disease with systemic consequences--clinical impact, mechanisms, and potential for early intervention

The natural course of chronic obstructive pulmonary disease (COPD) is complicated by the development of systemic consequences and co-morbidities. These may be major features in the clinical presentation of COPD, prompting increasing interest. Systemic consequences may be defined as non-pulmonary manifestations of COPD with an immediate cause-and-effect relationship, whereas co-morbidities are diseases associated with COPD. The major systemic consequences/co-morbidities now recognized are: deconditioning, exercise intolerance, skeletal muscle dysfunction, osteoporosis, metabolic impact, anxiety and depression, cardiovascular disease, and mortality. The mechanisms by which these develop are unclear. Probably many factors are involved. Two appear of paramount importance: systemic inflammation, which presents in some patients with stable disease and virtually all patients during exacerbations, and inactivity, which may be a key link to most COPD-related co-morbidities. Further studies are required to determine the role of inflammatory cells/mediators involved in systemic inflammatory processes in causing co-morbidities; the link between activity and co-morbidities; and how COPD therapy may affect activity. Both key mechanisms appear to be influenced significantly by COPD exacerbations. Importantly, although the prevalence of systemic consequences increases with increasing severity of airflow obstruction, both systemic consequences and co-morbidities are already present in the Global Initiative for Chronic Obstructive Lung Disease Stage II. This supports the concept of early intervention in chronic obstructive pulmonary disease. Although at present early intervention studies in COPD are lacking, circumstantial evidence suggests that current treatments may influence events leading to the systemic consequences and co-morbidities, and thus may affect the clinical manifestations of the disease.

Determinants of lung volumes in chronic spinal cord injury

OBJECTIVE

To characterize determinants of lung volumes in chronic spinal cord injury (SCI).

DESIGN

Cross-sectional.

SETTING

VA Boston Healthcare System.

PARTICIPANTS

White men (N=330) with chronic SCI.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Questionnaire responses and measurements of lung volumes.

RESULTS

Adjusted for SCI severity and stature, greater body mass index (BMI) was associated (all P<.05) with lower total lung capacity (TLC) (-38.7 mL x kg(-1) x m(-2)), functional residual capacity (FRC) (-73.9 mL x kg(-1) x m(-2)), residual volume (RV) (-40.4 mL x kg(-1) x m(-2)), and expiratory reserve volume (ERV) (-32.2 mL x kg(-1) x m(-2)). The effect of BMI on RV was most pronounced in quadriplegia (-72 mL x kg(-1) x m(-2)). Lifetime smoking was associated with a greater FRC (5.3 mL/pack-year) and RV (3.1 mL/pack-years). The effects of lifetime smoking were also greatest in quadriplegia (11 mL/pack-year for FRC; 7.8 mL/pack-year for RV). Time since injury, independent of age, was associated with a decrease in TLC, FRC, ERV, and RV (P<.05). Age was not a predictor of TLC once time since injury was considered.

CONCLUSIONS

Determinants of FRC, TLC, ERV, and RV in chronic SCI include factors related and unrelated to SCI. The mechanisms remain to be determined but likely involve the elastic properties and muscle function of the respiratory system and perhaps the effects of systemic inflammation related to adiposity. Addressing modifiable factors such as obesity, muscle stiffness, and smoking may improve respiratory morbidity and mortality in SCI by improving pulmonary function.

[Malnutrition in children with chronic bronchitis]

OBJECTIVE

To study nutritional status in children with chronic bronchitis (CB) in relation with lung function.

METHODS

In this cohort of study, 46 patients aged 6.0 to 17.5 years (mean: 11.9 years) with chronic bronchitis were recruited. None had cystic fibrosis. Body weight, height, skinfold thicknesses, percentage of ideal body weight-for-height (percentage of IBW), body mass index (BMI), BMI Z-score, fat mass and fat-free mass were used to evaluate nutritional status. Arterial blood gases, vital capacity (VC), forced expiratory volume in one s (FEV1), functional residual capacity (FRC) and maximum inspiratory (Pi(max)) and expiratory (Pe(max)) pressures at the mouth were used to evaluate respiratory function.

RESULTS

Thirteen children (28%) had malnutrition defined as percentage of IBW lower than 90%, with a predominant fat mass depletion. VC (65+/-13% versus 79+/-15%; p=0.006) and FEV1 (59+/-16% versus 69+/-14%; p=0.03) were significantly lower in children with malnutrition than in children without malnutrition, but no significant differences were observed with regard to the FEV1/VC ratio and blood gases. Pi(max) (56+/-11% versus 88+/-37%, p=0,02) and Pe(max) (46+/-12% versus 58+/-19%, p=0,3) were also lower in children with malnutrition as compared to than without malnutrition.

CONCLUSION

Malnutrition can be observed in children with CB and is associated with significant lower lung function parameters. This could be explained by decrease in respiratory muscle strength.

L-carnitine as an ergogenic aid for patients with chronic obstructive pulmonary disease submitted to whole-body and respiratory muscle training programs

The effects of adding L-carnitine to a whole-body and respiratory training program were determined in moderate-to-severe chronic obstructive pulmonary disease (COPD) patients. Sixteen COPD patients (66 +/- 7 years) were randomly assigned to L-carnitine (CG) or placebo group (PG) that received either L-carnitine or saline solution (2 g/day, orally) for 6 weeks (forced expiratory volume on first second was 38 +/- 16 and 36 +/- 12%, respectively). Both groups participated in three weekly 30-min treadmill and threshold inspiratory muscle training sessions, with 3 sets of 10 loaded inspirations (40%) at maximal inspiratory pressure. Nutritional status, exercise tolerance on a treadmill and six-minute walking test, blood lactate, heart rate, blood pressure, and respiratory muscle strength were determined as baseline and on day 42. Maximal capacity in the incremental exercise test was significantly improved in both groups (P < 0.05). Blood lactate, blood pressure, oxygen saturation, and heart rate at identical exercise levels were lower in CG after training (P < 0.05). Inspiratory muscle strength and walking test tolerance were significantly improved in both groups, but the gains of CG were significantly higher than those of PG (40 +/- 14 vs 14 +/- 5 cmH2O, and 87 +/- 30 vs 34 +/- 29 m, respectively; P < 0.05). Blood lactate concentration was significantly lower in CG than in PG (1.6 +/- 0.7 vs 2.3 +/- 0.7 mM, P < 0.05). The present data suggest that carnitine can improve exercise tolerance and inspiratory muscle strength in COPD patients, as well as reduce lactate production.

Temporal associations among energy intake, plasma linoleic acid, and growth improvement in response to treatment initiation after diagnosis of cystic fibrosis

OBJECTIVE

It is unclear why some patients with cystic fibrosis (CF) succeed ("responders") in recovering from malnutrition and growth faltering after treatment initiation whereas others fail to do so ("nonresponders"). We conducted a study to test the hypothesis that sustained high energy intake (increased EN) and normal plasma essential fatty acid status are critical determinants of treatment responsiveness within 2 years after diagnosis of CF.

METHODS

A total of 71 CF children who had pancreatic insufficiency but not meconium ileus and were enrolled in the Wisconsin CF Neonatal Screening Project were studied. Responders were defined by having achieved adequate weight gain, as indicated by a recovery of weight z score (Wtz) comparable to Wtz at birth (WtzBR) within 2 years of diagnosis. Increased EN and sustained normal plasma linoleic acid level (increased pLA) were defined by achieving energy intake > or =120% of estimated requirement for > or =75% of the time and maintaining plasma LA > or =26% of total fatty acids for > or =75% of the time, respectively.

RESULTS

Thirty-two (68%) screened patients and 13 (54%) patients whose CF was diagnosed conventionally recovered WtzBR within 2 years of diagnosis. Screened patients responded at significantly younger ages (mean/median: 6.3/4.3 months) than patients whose CF was diagnosed conventionally (mean/median: 15.8/11.8 months). Proportionately fewer screened patients (33%) achieved increased EN compared with patients whose CF was diagnosed conventionally (73%). However, more screened patients responded to increased EN and recovered WtzBR (91%) than patients whose CF was diagnosed conventionally (56%), although this difference was of borderline significance. Compared with having neither increased EN nor increased pLA, the likelihood of being a responder was greatest with combined increased EN and increased pLA, followed by increased EN only. The positive associations between increased EN and increased pLA to treatment responsiveness remained significant after adjustment for neonatal screening status, baseline height and weight status, and indices of pulmonary disease severity.

CONCLUSION

Increased EN and increased pLA are critical in promoting adequate weight gain in children with newly diagnosed CF.

Palliative management of refractory dyspnea in COPD

COPD is a progressive illness with worldwide impact. Patients invariably reach a point at which they require palliative interventions. Dyspnea is the most distressing symptom experienced by these patients; when not relieved by traditional COPD management strategies it is termed "refractory dyspnea" and palliative approaches are required. The focus of care shifts from prolonging survival to reducing symptoms, increasing function, and improving quality of life. Numerous pharmacological and non-pharmacological interventions can achieve these goals, though evidence supporting their use is variable. This review provides a summary of the options for the management of refractory dyspnea in COPD, outlining currently available evidence and highlighting areas for further investigation. Topics include oxygen, opioids, psychotropic drugs, inhaled furosemide, Heliox, rehabilitation, nutrition, psychosocial support, breathing techniques, and breathlessness clinics.

Nutritional support and quality of life in stable chronic obstructive pulmonary disease (COPD) patients

RATIONALE

Nutritional depletion is a common problem in chronic obstructive pulmonary disease (COPD) patients. It is caused, to a large extent, by an imbalance between low-energy intake and high-energy requirements. This problem adversely affects morbidity and mortality. However, the use of nutritional supplements to reach their energy necessities requires optimisation between positive and adverse effects on outcome before being used systematically as part of their comprehensive care.

PURPOSE

The aim of our study was to investigate the effects of oral nutritional repletion on quality of life in stable COPD patients.

METHODS

Prospective, randomised and multi-centre study. Stable COPD patients with a body mass index 22, a fat-free mass index 16, and/or a recent involuntary weight loss (5% during last month, or 10% during the last 3 months) were studied. Exclusion criteria were to present signs of an airway infection, to have a cardiovascular, neurological, or endocrine disease, to be treated with oral steroids, immunosuppressors or oxygen therapy at home, and to receive nutritional supplements. During 12 weeks, patients were encouraged to ingest a total daily defined energy intake. Randomly, in patients from group A the total daily energy load was Resting Energy Expenditure (REE)x1.7, and those from group B, REE x1.3. Total daily energy intake was achieved with regular food plus, if necessary, oral nutritional supplement rich in proteins (with 50% of whey protein), with predominance of carbohydrates over fat, and enriched in antioxidants. Primary end-point variable was quality of life. Secondary end-point outcomes included body weight, body composition, lung function, handgrip strength, and compliance with the energy intake previously planned. Data were treated with a SAS System. Student's test, Wilcoxon's rank sum test, and Mann-Whitney's test were used.

RESULTS

At baseline both groups of patients were comparable. All patients needed oral nutritional supplements to achieve total daily defined energy intake. After 12 weeks of follow-up, patients in both groups significantly increased energy intake. Patients in group A increased body weight (P=0.001), triceps skin fold thickness (P=0.009) and body fat mass (P=0.02), and decreased body fat-free mass index (P=0.02). In this group a marked increase in airflow limitation was observed. A tendency to increase body weight and handgrip strength, and to decrease airflow limitation was observed in patients from group B. Furthermore, patients in the later group showed a significant improvement in the feeling of control over the disease (P=0.007) and a tendency to better the other criteria in a quality of life scale.

CONCLUSIONS

According to our results, total daily energy intake of REE x 1.3 is preferable to REE x 1.7 in mild stable COPD patients. The administration of oral nutritional supplements, rich in proteins (with 50% of whey protein), with predominance of carbohydrates over fat, and enriched in antioxidants, to achieve total daily defined energy intake in patients in group B was followed by a significant improvement of one criteria (mastery) among many others in a quality of life scale.

Nutritional supplementation for stable chronic obstructive pulmonary disease

BACKGROUND

Low body weight in patients with chronic obstructive pulmonary disease (COPD) is associated with an impaired pulmonary status, reduced diaphragmatic mass, lower exercise capacity and higher mortality rate when compared to adequately nourished individuals with this disease. Nutritional support may therefore be a useful part of their comprehensive care.

OBJECTIVES

To conduct a systematic review of randomised controlled trials (RCTs) to clarify whether nutritional supplementation (caloric supplementation for at least 2 weeks) improved anthropometric measures, pulmonary function, respiratory muscle strength and functional exercise capacity in patients with stable COPD.

SEARCH STRATEGY

Randomized controlled trials (RCTs) were identified from the Cochrane Airways Group register of RCTs, a hand-search of abstracts presented at international meetings and consultation with experts. Searches are current as of March 2004.

SELECTION CRITERIA

Two reviewers independently selected trials for inclusion, assessed quality and extracted the data.

DATA COLLECTION AND ANALYSIS

Within each trial and for each outcome, we calculated an effect size. The effect sizes were then pooled by a random-effects model. Homogeneity among the effect sizes was also tested.

MAIN RESULTS

Eleven studies recruiting 352 participants met the inclusion criteria. Eight papers were considered as high quality. Two studies were double-blinded. For each of the outcomes studied, the effect of nutritional support was small: the 95% confidence intervals around the pooled effect sizes all included zero. The effect of nutritional support was homogeneous across studies.

AUTHORS' CONCLUSIONS

Nutritional support had no significant effect on anthropometric measures, lung function or exercise capacity in patients with stable COPD.

Factors Affecting Drug Prescription in Patients With Stable COPD: Results From a Multicenter Spanish Study

OBJECTIVE

To determine what factors are associated with prescription of drugs to patients with stable chronic obstructive pulmonary disease (COPD).

MATERIAL AND METHODS

We studied 568 patients with stable COPD. Assessments included determination of the severity of dyspnea, body mass index, health-related quality of life, and spirometry testing.

RESULTS

The forced expiratory volume in 1 second was significantly associated with prescription of long-acting beta2-adrenergic agonists (odds ratio [OR]=0.98; 95% confidence interval [CI], 0.96-1) and inhaled corticosteroids (OR=0.98; 95% CI, 0.96-1). Quality of life was related to administration of short-acting beta2-adrenergic agonists (OR=1.02; 95% CI, 1-1.03), long-acting beta2-adrenergic agonists (OR=1.02; 95% CI, 1-1.03), ipratropium bromide (OR=1.03; 95% CI, 1-1.04), theophylline drugs (OR=1.02; 95% CI, 1-1.03), and inhaled corticosteroids (OR=1.02; 95% CI, 1-1.03). The severity of dyspnea was significantly associated with prescription of oral corticosteroids (for grade IV dyspnea, OR=15.25; 95% CI, 2.40-97.02). Body mass index was not related to drug administration.

CONCLUSIONS

Drug prescription in patients with stable COPD correlates not only with forced expiratory volume in 1 second but also with other parameters such as health-related quality of life and dyspnea.

Both generic and disease specific health-related quality of life are deteriorated in patients with underweight COPD

This study evaluated the effects of body weight on both generic and disease-specific health-related quality of life (HRQoL) of patients with COPD. A total of 83 patients with stable COPD were enrolled (mean age: 74.6 yr, mean FEV1: 1.29 L). Patients were divided into two groups according to body mass index (BMI) (UW group: BMI < or = 20, NW group: 20 < BMI < or = 26). The degree of dyspnea and both disease-specific and generic HRQoL were compared between the two groups. An oxygen cost diagram (OCD) was used to assess the degree of dyspnea and St. George's Respiratory Questionnaire (SGRQ) and Medical Outcomes Study Short Form 36-item Questionnaire (SF-36) were used for HRQoL evaluation. The OCD was significantly lower in the UW group. Compared with the NW group, the UW group showed significant deterioration in the total score and three subscales of SGRQ. SF-36 also showed significantly worse scores for the parameters of physical functioning, role emotional, bodily pain, and general health. The results of stepwise multiple regression analysis showed that OCD, FEV1, %pred. BMI were independent variables in the total score on SGRQ. The results of stepwise multiple regression analysis also showed that OCD was an independent variable for four of eight components of SF-36, while BMI was three of eight components of SF-36. In conclusion, low body weight in patients with COPD is related to a worsening of dyspnea and deterioration of both generic and disease-specific HRQoL. The present results also indicate that nutritional intervention may be important for improving dyspnea and HRQoL in patients with COPD.

[Prevalence of malnutrition in outpatients with stable chronic obstructive pulmonary disease]

OBJECTIVE

To determine the prevalence of malnutrition in outpatients with stable chronic obstructive pulmonary disease (COPD) followed at a respiratory clinic.

MATERIAL AND METHOD

In this prospective study, we assessed the nutritional status of consecutive outpatients with stable COPD by investigating various anthropometric parameters. Patients were malnourished (low body weight) if their body mass index was within the bottom quartile of a reference population. Muscle mass was determined from the midarm muscle area and if this mass was at or within the bottom quartile, muscle wasting was present. Albumin and transferrin plasma concentrations were used as a measure of visceral protein stores. Fat stores were assessed from body fat and if this value was at or within the bottom quartile, calorific malnutrition was present. All patients underwent arterial blood gas sampling at rest and spirometry.

RESULTS

A total of 178 patients--one woman (0.6%) and 177 men (99.4%)--were enrolled in the study, with a mean (SD) age of 69 (9) years. We found low body weight in 19.1% of the patients, muscle wasting in 47.2%, visceral protein depletion in 17.4%, and fat depletion in 19.1%. Of the patients with normal weight, 62.9% showed muscle wasting. The proportion of patients with a body mass index or midarm muscle area at or within the bottom quartile increased significantly with increased bronchial obstruction (P<.001 and P=.015, respectively), though 35.7% of the patients showed muscle wasting even when COPD was mild.

CONCLUSIONS

Many patients with stable COPD suffer malnutrition. Nutritional state is worse with more severe COPD. Depletion involves both fat stores and muscle and visceral protein stores, but the greatest effect is seen in muscle wasting. A significant number of patients with normal weight also suffer muscle wasting. Although changes in body composition were common in our patients, low body weight was less prevalent than has been reported for populations in countries that are socially and economically similar to Spain.

Prognostic value of nutritional depletion in patients with COPD treated by long-term oxygen therapy: data from the ANTADIR observatory

BACKGROUND

An association between weight depletion and mortality has been demonstrated in patients with COPD, but the prognostic influence of malnutrition has not been evaluated in patients with the most severe COPD treated with home long-term oxygen therapy (LTOT).

STUDY OBJECTIVE

To analyze the prognostic value of nutritional depletion in patients with COPD receiving LTOT with respect to survival and hospitalization rate.

DESIGN

Analysis of a national database (Observatory of Association Nationale pour le Traitement a Domicile de l'Insuffisance Respiratoire Chronique [ANTADIR]).

SETTING

The national nonprofit network for home treatment of patients with chronic respiratory insufficiency (ANTADIR) founded in France in the 1980s.

PATIENTS

A total of 4,088 patients with a diagnosis of chronic bronchitis or emphysema, FEV(1)/vital capacity ratio < 60%, PaO(2) < 8 kPa, and treatment with LTOT between 1984 and 1993.

MEASUREMENTS AND RESULTS

The prevalence of malnutrition, as defined by a body mass index (BMI) < 20, was 23% in men and 30% in women. BMI was significantly correlated with FEV(1) and FEV(1)/VC. The mean follow-up duration was 7.5 years. The 5-year survival rates were 24%, 34%, 44%, and 59%, respectively, for patients with BMIs < 20, 20 to 24, 25 to 29, and > or = 30. Multivariate analysis using the Cox model demonstrated that the effect of BMI on survival was independent of age, FEV(1), PaO(2), and sex. Lower BMI was the most powerful predictor of duration and rate of hospitalization, independently of blood gas levels and respiratory function. The mean (+/- SD) annual time spent in the hospital was 29.6 +/- 40.4 days for patients with a BMI < 20 vs 17.5 +/- 30.1 days for patients with a BMI > 30.

CONCLUSION

This study showed that nutritional depletion is an independent risk factor for mortality and hospitalization in patients with COPD receiving LTOT. The best prognosis was observed in overweight and obese patients.

Chronic obstructive pulmonary disease and malnutrition: why are we not winning this battle?

OBJECTIVES: To review the mechanisms involved in the origin of malnutrition in patients with chronic obstructive pulmonary disease (COPD), and to make a systematic review of randomized controlled studies, to clarify the contribution of nutritional supplementation in patients with stable COPD. METHOD: A systematic review of articles published in the field of nutrition, in any language and from several sources, including Medline, Embase, Cinahl, and the Cochrane Registry on COPD, as well as studies presented at congresses in the US and Europe. RESULTS: Studies on nutritional supplementation for more than two weeks showed a very small effect, not reaching statistical significance. A linear regression study found that old age, relative anorexia, and high inflammatory response are associated with non-response to nutritional therapy. CONCLUSION: Currently, there is no evidence that nutritional supplementation is truly effective in patients with COPD. Factors associated with non-response suggest a relationship with the degree of inflammation, including high TNF-alpha levels. Measuring inflammation markers may be useful to determine prognosis and adequate therapy. Treatment with anti-inflammatory cytokines or cytokine inhibitors seems promising for the future.

Nutritional supplementation for stable chronic obstructive pulmonary disease

BACKGROUND

Low body weight in patients with chronic obstructive pulmonary disease (COPD) is associated with an impaired pulmonary status, reduced diaphragmatic mass, lower exercise capacity and higher mortality rate when compared to adequately nourished individuals with this disease. Nutritional support may therefore be a useful part of their comprehensive care.

OBJECTIVES

To conduct a systematic review of randomized controlled trials (RCTs) to clarify whether nutritional supplementation (caloric supplementation for at least 2 weeks) improved anthropometric measures, pulmonary function, respiratory muscle strength and functional exercise capacity in patients with stable COPD.

SEARCH STRATEGY

Randomized controlled trials (RCTs) were identified from the Cochrane Airways Group register of RCTs, a hand-search of abstracts presented at international meetings and consultation with experts.

SELECTION CRITERIA

Two reviewers independently selected trials for inclusion, assessed quality and extracted the data.

DATA COLLECTION AND ANALYSIS

Within each trial and for each outcome, we calculated an effect size. The effect sizes were then pooled by a random-effects model. Homogeneity among the effect sizes was also tested.

MAIN RESULTS

From 272 references, nine RCTs were ultimately included. Six papers were considered as high quality and only two studies were double-blinded. For each of the outcomes studied, the effect of nutritional support was small: the 95% confidence intervals around the pooled effect sizes all included zero. The effect of nutritional support was homogeneous across studies. An additional search conducted in August 2001 did not identify further studies.

REVIEWER'S CONCLUSIONS

Nutritional support had no significant effect on anthropometric measures, lung function or exercise capacity in patients with stable COPD.

[Relationship between dyspnea and quality of life with body mass index and pulmonary function in patients with chronic obstructive airways disease and emphysema]

BACKGROUND

We aimed to evaluate the differences in pulmonary function, quality of life (CVRS) and dyspnea in patients with chronic obstructive pulmonary disese (COPD) and emphysema according to the body mass index (BMI). Moreover, we analyzed the relation between BMI, pulmonary function, CVRS and dyspnea.

PATIENTS AND METHOD

This was a prospective, 12-months study including 20 patients with COPD and emphysema. They were classified in group A (BMI < 21 kg/m(2) group B (BMI >= 21 kg/m(2)). We performed pulmonary function tests and determined the levels of dyspnea and CVRS according to a scale of dyspnea and a CVRS questionnaire.

RESULTS

Seven patients had a BMI < 21 kg/m(2) and it was >=21 kg/m(2) in 13 patients. DLCO in group A patients was lower than in group B. After a multiple regression analysis, the FVC accounted for 52% of dyspnea variability. Both PEM and dyspnea were the parameters that better predicted the CVRS.

CONCLUSIONS

Patients with COPD and emphysema with a VMI < 21 kg/m(2) have a lower DLCO than patients with a BMI >= 21 kg/m(2). In our patients, dyspnea sensation depended on the FVC. In addition,the CVRS depended on dyspnea sensation and PEM.

Nutritional intervention in COPD: a systematic overview

OBJECTIVE

We conducted a systematic overview of randomized controlled trials (RCTs) to clarify the contribution of nutritional supplementation for patients with stable COPD.

METHODS

RCTs were identified from several sources, including the Cochrane Airways Group register of RCTs, a hand search of abstracts presented at international meetings, and consultation with experts. Two reviewers independently selected trials for inclusion, assessed quality, and extracted the data.

RESULTS

Twenty-one reports were classified according to the type, duration of supplementation, and the presence of anabolic substances. High carbohydrate meals were associated with an increase in carbon dioxide production and a decrease in exercise capacity. Short-term crossover studies in which diets of various compositions were administered supported the notion that high carbohydrate loads increase the stress on the ventilatory system. The influence of longer-term supplementation (> 2 weeks) on weight, anthropometry, and exercise capacity varied, without there being a consistent effect. Lean body weight was only occasionally reported and health-related quality of life too rarely to be included as an outcome. The influence of recombinant human growth hormone was disappointing. Anabolic steroids increased body weight and lean body mass, but had little influence on exercise capacity.

CONCLUSION

This systematic overview in patients with COPD supports the notion that those with marginal ventilatory reserve might benefit from a dietary regimen in which a high percentage of calories are supplied by fat. Although there are reports of the benefits of nutritional repletion, trials of > 2 weeks failed to show consistent benefit on body weight. Evaluating nutritional repletion is hampered by the absence of information regarding body composition, exercise, and health-related quality of life. Growth hormone has not been shown to be useful. Further studies are needed to refine the beneficial effects of anabolic steroids as adjunctive agents together with nutritional support and exercise.

Influence of body weight on the severity of dyspnea in chronic obstructive pulmonary disease

A substantial number of patients with COPD are underweight (UW); they comprise the clinical subtype of "dyspneic" or emphysematous. To determine whether these patients are more dyspneic than normal weight (NW) patients with COPD, we quantitated the severity of dyspnea, using a modified Medical Research Council (MRC) dyspnea scale, in 33 UW and 57 NW patients and compared their pulmonary function tests (PFTs), arterial blood gases (ABGs), and respiratory muscle strength as estimated by maximum static inspiratory (PI(max)) and expiratory (PE(max)) mouth pressures (all as means +/- SEM). Body mass index was 18.7 +/- 1.2 and 24.5 +/- 1.8 kg/m(2) in UW and NW patients, respectively (p < 0.0001). The MRC dyspnea scale was 3. 1 +/- 0.9 in UW and 2.5 +/- 1.2 in NW groups (p = 0.035). All PFT and ABG parameters were similar in the two groups except for DCO (36 +/- 11% in UW and 57 +/- 17% in NW, p < 0.001) and PI(max) (55 +/- 18 mm Hg in UW and 66 +/- 19 mm Hg in NW, p = 0.020). In a stepwise multiple regression model, %DCO and %MVV combined were the best predictors of dyspnea severity (R(2) = 0.30, p = 0.001). We conclude that UW patients with COPD are more dyspneic than NW patients. Although the origin of dyspnea in COPD is multifactorial, changes in DCO and respiratory muscle strength may contribute to its intensity.

Smoking and chronic obstructive pulmonary disease

Smoking is overwhelmingly the major cause of chronic bronchitis and emphysema worldwide. Additional risk factors for developing COPD are presented, along with the variables that govern cigarette smoke deposition in the lung. Major paradigms for the pathogenesis of COPD, including the protease-antiprotease and oxidant-antioxidant theories are described, and evidence for impaired reparative mechanisms in the causation of emphysema is noted. A description of the natural history of declining lung function in smokers and in the susceptible subset of smokers that ultimately develop smoking-induced COPD is accompanied by a discussion of the effects of smoking cessation on preservation of lung health. The disordered ventilation and gas-exchange physiology in the cigarette smoke-damaged lung is explained on the basis of the observed morphological changes.

Nutritional support for individuals with COPD: a meta-analysis

RATIONALE

Malnutrition in patients with COPD is associated with an impaired pulmonary status, reduced diaphragmatic mass, lower exercise capacity, and higher mortality rate when compared to adequately nourished individuals with COPD. Nutritional support may therefore be a useful part of their comprehensive care.

PURPOSE

To conduct a meta-analysis of randomized controlled trials (RCTs) to clarify whether nutritional supplementation (caloric supplementation for at least 2 weeks) improved anthropometric measures, pulmonary function, respiratory muscle strength, and functional exercise capacity in patients with stable COPD.

METHODS

RCTs were identified from several sources, including the Cochrane Airways Group register of RCTs, a hand search of abstracts presented at international meetings, and consultation with experts. Two reviewers independently selected trials for inclusion, assessed quality, and extracted the data. Within each trial and for each outcome, we calculated an effect size. The effect sizes were then pooled by a random-effects model. Homogeneity among the effect sizes was also tested.

RESULTS

From 272 references, nine RCTs were ultimately included. Six articles were considered as high quality. Only two studies were double blinded. For each of the outcomes studied, the effect of nutritional support was small: the 95% confidence intervals around the pooled effect sizes all included zero. The effect of nutritional support was homogeneous across studies.

CONCLUSION

Nutritional support had no effect on improving anthropometric measures, lung function, or functional exercise capacity among patients with stable COPD.

Tissue wasting in patients with chronic obstructive pulmonary disease

Malnutrition is common among individuals suffering from hypoxemic chronic obstructive pulmonary disease (COPD), advanced HIV disease, and in patients with chronic, severe congestive heart failure. Although increased morbidity and mortality has been associated with weight loss in these conditions, the pathophysiology of malnutrition remains somewhat unclear for each. In COPD, the primary postulated mechanism is hypermetabolism resulting in elevated total caloric expenditure arising from increased airway resistance, increased O2 cost of ventilation, increased dietary induced thermogenesis, inefficient substrate use and perhaps, increased levels of proinflammatory cytokines. In AIDS, postulated mechanisms include hypermetabolism arising from increased activation of proinflammatory cytokines, along with futile cycling of fatty acids and de novo lipogenesis early in the course of HIV infection; intestinal malabsorption and anorexia also play a role in many inflicted individuals. In cardiac cachexia, dietary and metabolic factors, and levels and activity of cytokines, thyroid hormone, catecholamines and cortisol have been suggested as being responsible for causing weight loss in a most cases.

Inflammation and repair processes in chronic obstructive pulmonary disease

COPD is characterized by chronic inflammation and injury of both the airways and the parenchymal structures of the lung. These processes are associated with ongoing repair. Whether repair leads to restoration of normal tissue architecture or to altered tissue structure with loss of function depends on complex interrelationships of a variety of interacting mediators. The possibility that repair processes can be modulated by exogenous agents raises the possibility that therapeutic strategies aimed at repair can be effective. Such strategies offer tremendous promise both for slowing the relentlessly progressive natural history which most often characterizes COPD and, possibly, for restoring lung function. Rennard SI. Inflammation and repair processes in chronic obstructive pulmonary disease.

Elevated O2 cost of ventilation contributes to tissue wasting in COPD

BACKGROUND AND OBJECTIVES

Thirty to 50% of all COPD patients experience tissue wasting that may be caused by hypermetabolism, but the cause of the perturbed metabolic state is unclear. We hypothesized that the elevated O2 cost of ventilation (O2 COV) may be a contributing factor. All of the data are presented as means (+/-SEM). Ten hypoxemic (a PaO2 of 54+/-3 mm Hg) stable COPD patients (an FEV1/FVC ratio of 42+/-4%) and five healthy control subjects were studied. The patients were divided into two groups based on nutritional status. Group 1 (n = 6) was malnourished (a body mass index [BMI] of 17.6+/-0.7 kg/m2), and group 2 (n = 4) was normally nourished (a BMI of 26.0+/-3 kg/m2). The O2 COV was determined by measuring the change in the oxygen consumption (VO2) and the minute ventilation (VE) caused by CO2-induced hyperventilation.

RESULTS AND CONCLUSIONS

Group 1 had an elevated O2 COV when compared to group 2 and the control group, respectively: 16.4+/-1.0 vs 9.7+/-1.0 and 2.4+/-0.2 mL O2/L of VE (p < 0.05). The VO2 at rest was higher for group 1 than for group 2 and the control group, respectively: 4.5+/-0.3 vs 3.1+/-0.5 and 3.4+/-0.2 mL/kg/min (p < 0.05). The resting energy expenditure (REE) % predicted for group 1 was also higher than group 2 and the control group, respectively: 125+/-3% vs 87+/-7% and 97+/-2% (p < 0.05). Significant correlations were observed that implicate the increased O2 COV as a cause of tissue wasting: O2 COV vs BMI (r = -0.79; p = 0.007), O2 COV vs REE % predicted (r = 0.66; p = 0.039), and REE % predicted vs BMI (r = -0.83; p = 0.003). The O2 COV was also correlated with lung function: FEV1/FVC vs O2 COV (r = -0.84; p = 0.002). We conclude that in these COPD patients the O2 COV is associated with an increased metabolic rate which, in turn adversely affects the nutritional status.