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

Scaling skeletal muscle function to mass in patients with moderate-to-severe COPD

Skeletal muscle performance and muscle mass are commonly reduced in patients with advanced chronic obstructive pulmonary disease (COPD). It is currently unclear, however, whether negative changes in muscle structure and function are proportionately related to each other in these patients. In a cross-sectional study, 39 patients (post-bronchodilator FEV1=49.7+/-15.5% pred) and 17 controls were submitted to knee isokinetic dynamometry [peak torque (PT), isometric strength (IS), and total work (TW)] and dual energy X-ray absorptiometry for the evaluation of leg muscle mass (LMM). Muscle function (F) was normalised for LMM by using ratio standards (F.LMM-1), power function ratios (F.LMM-b, where b is usually not equal 1), and analysis of covariance (ANCOVA). Patients with COPD presented with reduced PT, IS, TW, and LMM as compared to controls: there were significant linear correlations among these variables in both groups (P<0.05). Ratio standards of PT.LMM-1 and TW.LMM-1 were, on average, 14% lower in patients than controls (P<0.01). The coefficients for allometric correction of IS and TW were significantly higher in patients as compared to controls (0.975 vs. 0.603 and 1.471 vs. 0.824, respectively, P<0.05), i.e. more LMM was needed to generate a given functional output in patients than normal subjects. In addition, adjusted means of muscle function variables by ANCOVA were 11-18% lower for patients than controls with LMM as the covariate (P<0.05). We conclude that factors other than simple atrophy (i.e. mass-independent mechanisms) might play a role in explaining the COPD-related skeletal muscle dysfunction.

Body composition in patients with chronic obstructive pulmonary disease: which method to use in clinical practice?

The objective of the present study was to compare anthropometry with bioelectrical impedance (BIA) in relation to densitometry (dual-energy X-ray absorptiometry; DEXA) as methods of nutritional assessment and body composition in out-patients with chronic pulmonary obstructive disease (COPD). We conducted a cross-sectional clinical study with sixty-one patients with COPD (forty-two men and nineteen women), mean age of 66.5 (sd 7.9) years and forced expiratory volume in 1 s of 1.3 (sd 0.6) litres (52.2 (sd 19.8) % predicted), referred to the Pulmonary Rehabilitation Center. The patients were evaluated regarding nutrition status and body composition as determined by anthropometry, BIA and DEXA. In the results, 34.4 % showed mild obstruction, 31.2 %, moderate and 34.4 %, severe obstruction. According to the BMI (mean 24.5 (sd 4.5) kg/m2), 45.9 % of the patients exhibited normal weight, while 27.9 % were underweight and 26.2 % were obese. Related to fat-free mass (FFM), anthropometry and BIA compared with DEXA presented high correlations (r 0.96 and 0.95 respectively; P < 0.001) and high reliability between the methods (alpha 0.98; P < 0.001). Agreement analysis between the methods shows that anthropometry overestimates (0.62 (sd of the difference 2.89) kg) while BIA underestimates FFM (0.61 (sd of the difference 2.82) kg) compared with DEXA. We concluded that according to the nutritional diagnosis, half of our population of patients with COPD showed normal weight, while the other half comprised equal parts obese and underweight patients. Body composition estimated by BIA and anthropometry presented good reliability and correlation with DEXA; the three methods presented satisfactory clinical accuracy despite the great disparity of the limits of agreement.

Prevalence of nutritional depletion in a large out-patient population of patients with COPD

OBJECTIVE

The present study focuses on the prevalence of nutritional depletion in relation to functional performance, airflow limitation, experienced dyspnoea and health status in a large multi-center out-patient population with chronic obstructive pulmonary disease (COPD).

METHODS

In 39 out-patient centers in The Netherlands, 389 patients with moderate to severe COPD (217 men) were recruited. The study evaluated on the baseline characteristics of the COSMIC study. Measurements included body composition by bioelectrical impedance analysis, dyspnoea by MRC-score, peripheral muscle function by isometric handgrip strength and disease-specific health status by St. George Respiratory Questionnaire.

RESULTS

The prevalence of nutritional depletion (defined as body mass index (BMI)<or=21 kg/m2 and/or fat-free mass index (FFMI)<or=15 (females) or <or=16 (males) kg/m2) was high (27%). Prevalence of normal BMI and low FFMI was 15%, and of low BMI and low FFMI 11%. The prevalence of low BMI as well as low FFMI was significantly higher in female than in male COPD patients, 18% and 40% vs. 10% and 20%, respectively (both P<0.01). No differences in FEV1%predicted, dyspnoea score and health status were observed between depleted and non-depleted COPD patients. Multiple linear regression analysis in the total group showed that handgrip strength correlated with FFMI after correction for sex distribution and age, but not FEV1%predicted.

CONCLUSIONS

The prevalence of nutritional depletion was high in a large out-patient COPD population in The Netherlands, especially in female COPD patients. Depletion of FFM was associated with impaired peripheral muscle strength, independent of disease severity.

The effect of obesity on chronic respiratory diseases: pathophysiology and therapeutic strategies

Sedentary lifestyles and increased pollution brought about by industrialization pose major challenges to the prevention of both obesity and chronic respiratory diseases such as chronic obstructive pulmonary disease (COPD), asthma, obstructive sleep apnea and obesity hypoventilation syndrome. Obesity has emerged as an important risk factor for these respiratory diseases, and in many instances weight loss is associated with important symptomatic improvement. Moreover, obesity may influence the development and presentation of these diseases. In this article, we review the current understanding of the influence of obesity on chronic respiratory diseases and the clinical management of obesity concurrent with asthma, COPD, obstructive sleep apnea or obesity hypoventilation syndrome.

Peak anaerobic power in patients with COPD: gender related differences

The aim of the study was to investigate peak anaerobic power during all-out exercise in patients with COPD. Twenty patients (ten women, ten men) [FEV1=50.5 (7.6)% of predicted] and 11 healthy subjects (six women, five men) performed: (1) three maximal sprints on a cycle ergometer to measure peak anaerobic power (Pmax) and optimal velocity (Vopt), (2) assessment of whole-body composition by dual-energy X-ray absorptiometry (DEXA) and (3) assessment of mean habitual daily energy expenditure (MHDEE). Pmax was 30% lower in COPD than in healthy subjects [22.9 (7.1) vs. 32.8 (5.6) W kg-1 (legs FFM), P<0.001]. Nevertheless, Vopt was similar in both series. In COPD, Pmax was lower in women than in men [21.4 (7.7) vs. 23.8(6.4) W kg-1 (legs FFM), P<0.05]. Vopt was lower in women than in COPD men [72.6 (11.3) vs. 89.3 (13.8) rpm, P<0.05]. MHDEE was lower in COPD than in healthy subjects [8019 (1254) vs. 9093 (1660) kJ day-1]. In COPD, MHDEE was lower in women than in men (P<0.001). This study demonstrates that in COPD patients, the decrease in peak anaerobic power could play a role in their specific muscular dysfunction. Considerable differences were observed in peripheral muscle function, body composition and MHDEE between women and men. The skeletal muscle of women and men may therefore adapt to COPD in different ways.

Greater whole-body myofibrillar protein breakdown in cachectic patients with chronic obstructive pulmonary disease

BACKGROUND

Experimental studies indicate that greater skeletal muscle protein breakdown is a trigger for the cachexia that often is prevalent in chronic obstructive pulmonary disease (COPD).

OBJECTIVE

We compared myofibrillar protein breakdown (MPB) with whole-body (WB) protein breakdown (PB) in 9 cachectic COPD patients [x +/- SEM forced expiratory volume in 1 s (FEV(1)): 48 +/- 4% of predicted], 7 noncachectic COPD patients (FEV(1): 53 +/- 5% of predicted), and 7 age-matched healthy control subjects, who were matched by body mass index with the noncachectic patients.

DESIGN

After the subjects fasted overnight (10 h) and discontinued the maintenance medication, a primed constant and continuous infusion protocol was used to infuse L-[ring-(2)H(5)]-phenylalanine and L-[ring-(2)H(2)]-tyrosine to measure WB protein turnover and L-[(2)H(3)]-3-methylhistidine to measure WB MPB. Three arterialized venous blood samples were taken between 80 and 90 min of infusion to measure amino acid concentrations and tracer enrichments.

RESULTS

Body composition, WB protein turnover, and WB MPB did not differ significantly between the noncachectic COPD and control subjects. Cachectic COPD patients had lower fat mass and fat-free mass values (both: P < 0.01) than did the noncachectic COPD patients. WB MPB was significantly (P < 0.05) higher in the cachectic COPD group (18 +/- 3 nmol . kg(-1) . min(-1)) than in the combined control and noncachectic COPD groups (10 +/- 1 nmol . kg(-1) . min(-1)), but WB protein turnover did not differ significantly between the groups. Correlations with fat-free mass were significant (P < 0.05) for plasma glutamate and branched-chain amino acids, and that for WB MPB trended toward significance (P = 0.07).

CONCLUSION

Cachexia in clinically stable patients with moderate COPD is characterized by increased WB MPB, which indicates that myofibrillar protein wasting is an important target for nutritional and pharmacologic modulation.

Manifestações sistêmicas na doença pulmonar obstrutiva crônica

A doença pulmonar obstrutiva crônica é progressiva e está relacionada a uma resposta inflamatória anormal dos pulmões à inalação de partículas e/ou gases tóxicos, sobretudo a fumaça de cigarro. Embora acometa primariamente os pulmões, diversas manifestações extrapulmonares relacionadas a esta enfermidade têm sido descritas. O aumento do número de células inflamatórias, que resulta em produção anormal de citocinas pró-inflamatórias, e o desequilíbrio entre a formação de radicais livres e a capacidade antioxidante, resultando em sobrecarga oxidativa, provavelmente são mecanismos envolvidos na inflamação local e sistêmica. Além disso, a diminuição do condicionamento físico secundária às limitações ventilatórias pode estar envolvida no desenvolvimento de alterações musculares. A doença pulmonar obstrutiva crônica apresenta diversas manifestações sistêmicas que incluem a depleção nutricional, a disfunção dos músculos esqueléticos, que contribui para a intolerância ao exercício, e as manifestações relacionadas a co-morbidades comumente observadas nestes pacientes. Essas manifestações têm sido relacionadas à sobrevida e ao estado geral de saúde dos pacientes. Nesse sentido, esta revisão tem como objetivo discutir os achados da literatura relacionados às manifestações sistêmicas da doença pulmonar obstrutiva crônica, ressaltando o papel da inflação sistêmica, e algumas perspectivas de tratamento.

ESPEN Guidelines on Enteral Nutrition: Cardiology and Pulmonology

These guidelines are intended to give evidence-based recommendations for the use of enteral nutrition (EN) in patients with chronic heart failure (CHF) and chronic obstructive pulmonary disease (COPD). They were developed by an interdisciplinary expert group in accordance with officially accepted standards and are based on all relevant publications since 1985. They have been discussed and accepted in a consensus conference. EN by means of oral nutritional supplements (ONS) or tube feeding (TF) enables nutritional intake to be maintained or increased when normal oral intake is inadequate. No data are yet available concerning the effects of EN on cachexia in CHF patients. However, EN is recommended to stop or reverse weight loss on the basis of physiological plausibility. In COPD patients, EN in combination with exercise and anabolic pharmacotherapy has the potential to improve nutritional status and function. Frequent small amounts of ONS are preferred in order to avoid postprandial dyspnoea and satiety as well as to improve compliance.

Body mass, fat-free body mass, and prognosis in patients with chronic obstructive pulmonary disease from a random population sample: findings from the Copenhagen City Heart Study

RATIONALE

Low body mass index (BMI) is a marker of poor prognosis in chronic obstructive pulmonary disease (COPD). In the general population, the harmful effect of low BMI is due to the deleterious effects of a low fat-free mass index (FFMI; fat-free mass/weight(2)).

OBJECTIVES

We explored distribution of low FFMI and its association with prognosis in a population-based cohort of patients with COPD.

METHODS

We used data on 1,898 patients with COPD identified in a population-based epidemiologic study in Copenhagen. FFM was measured using bioelectrical impedance analysis. Patients were followed up for a mean of 7 yr and the association between BMI and FFMI and mortality was examined taking age, sex, smoking, and lung function into account.

MAIN RESULTS

The mean FFMI was 16.0 kg/m(2) for women and 18.7 kg/m(2) for men. Among subjects with normal BMI, 26.1% had an FFMI lower than the lowest 10th percentile of the general population. BMI and FFMI were significant predictors of mortality, independent of relevant covariates. Being in the lowest 10th percentile of the general population for FFMI was associated with a hazard ratio of 1.5 (95% confidence interval, 1.2-1.8) for overall mortality and 2.4 (1.4-4.0) for COPD-related mortality. FFMI was also a predictor of overall mortality when analyses were restricted to subjects with normal BMI.

CONCLUSIONS

FFMI provides information in addition to BMI and assessment of FFM should be considered in the routine assessment of COPD.

Supplemental oxygen prevents exercise-induced oxidative stress in muscle-wasted patients with chronic obstructive pulmonary disease

RATIONALE

Although oxygen therapy is of clear benefit in patients with severe chronic obstructive pulmonary disease (COPD), recent studies have shown that short-term supplementary oxygen may increase oxidative stress and inflammation within the airways.

OBJECTIVE

We investigated whether systemic inflammation and oxidative stress at rest and during exercise in patients with COPD are influenced by supplemental oxygen.

METHODS

Nine normoxemic, muscle-wasted patients with moderate to very severe COPD were studied. Plasma markers of systemic inflammation (leukocyte counts, interleukin 6 [IL-6]) and oxidative stress (lipid peroxidation, protein oxidation, antioxidant capacity) were measured after treatment with either supplemental oxygen (nasal, 4 L . min(-1)) or compressed air, both at rest (1 h treatment) and after submaximal exercise (40 W, constant work rate). In addition, free-radical production by neutrophils and ATP-degradation products were determined before and after exercise.

RESULTS

Short-term oxygen breathing at rest did not influence systemic low-grade inflammation and oxidative stress. The IL-6 response to exercise was attenuated during cycling with supplemental oxygen. Exercise-induced lipid and protein oxidation were prevented by treatment with supplemental oxygen. This was associated with both decreased free-radical production by neutrophils and reduced formation of (hypo)xanthine and uric acid.

CONCLUSION

Short-term supplementary oxygen does not affect basal systemic inflammation and oxidative stress but prevents exercise-induced oxidative stress in normoxemic, muscle-wasted patients with COPD, and attenuates plasma IL-6 response. Inhibition of neutrophil activation and ATP degradation appears to be involved in this effect.

Pulmonary Rehabilitation in Patients Undergoing Lung-Volume Reduction Surgery

Chronic obstructive pulmonary disease (COPD) is the most common form of primary pulmonary disability. Few effective treatment options exist for it, but recently, lung-volume reduction surgery (LVRS) has been shown to be effective in selected patients with emphysema. Pulmonary rehabilitation is an integral part of the preparation for and recovery from the procedure and has significant benefit in helping to improve the quality of life and conditioning of patients with COPD who undergo LVRS.

OVERALL ARTICLE OBJECTIVES

(a) To describe the role of pulmonary rehabilitation in LVRS, (b) to understand the components of a comprehensive pulmonary rehabilitation program, and (c) to describe the effects of a pulmonary rehabilitation program.

Measuring body composition in chronic heart failure: A comparison of methods

AIMS

Fat-free mass (FFM) is increasingly recognized as a systemic marker of disease severity in chronic organ failure and is an important target for physiologic and pharmacologic interventions to improve functional status. The aim of this study was therefore to evaluate two clinical methods to assess FFM in patients with chronic heart failure (CHF) using deuterium dilution (DEU) as reference and bromide dilution to assess the ratio between intracellular (ICW) and extracellular water (ECW) as potential confounder.

METHODS

Body composition was measured with dual-energy X-ray absorptiometry (DXA), bioelectrical impedance analysis (BIA) and DEU in 22 stable patients from our heart failure outpatient clinic and 24 healthy age matched controls.

RESULTS

FFM values measured by DXA and DEU in patients (r = 0.92, SEE: 3.1 kg) and controls (r = 0.99, SEE: 1.3 kg) were strongly related. In both patients and controls, the inter method difference increased with higher values of FFM (DXA overestimating DEU). The ICW/ECW ratio was within the normal range and comparable between the groups. In patients, a highly significant correlation coefficient was found (r = 0.93, SEE 2.1 p = 0.01) between total body water (DEU) and height squared/resistance (Ht2/R). On multiple regression next to Ht2/R, body weight was an independent predictor of FFM(DEU) (r = 0.95, SEE 2.5 kg, p<0.001; TBWdeu = 0.528 Ht2/R + (0.182 weight) + 8.277).

CONCLUSION

DXA and DEU are appropriate and interchangeable laboratory methods for assessment of FFM in clinically stable heart failure patients, however, overestimation of FFM(DXA) should be considered. BIA is a suitable clinical alternative for diagnostic purposes.

Systemic effects of COPD

Chronic obstructive pulmonary disease (COPD) is characterised by a range of pathological changes of the respiratory system, including airflow limitation secondary to structural changes of the small airways and loss of alveolar attachments, inflammation, ciliary dysfunction, and increased mucous production. COPD also has significant systemic consequences. The relationships between these pulmonary and nonpulmonary morbidities are not fully understood, and this further complicates the assessment of disease severity and prognosis. Although improving lung function and disease symptoms have been the main focus of COPD management, these parameters alone do not reflect the full burden of disease. More recent endeavours have highlighted the potential role of addressing physical limitations imposed by systemic alterations. It is evident that systemic manifestations are common in COPD. Indeed, many patients demonstrate a gradual and significant weight loss that exacerbates the course and prognosis of disease. This weight loss is often accompanied by peripheral muscle dysfunction and weakness, which markedly contribute to exercise limitation and impaired quality of life. Weight loss has been postulated to be the result of a high metabolic rate that is not compensated for by increased dietary intake. The cause of this elevated metabolism is a matter of much debate, and several factors have been implicated. Similarly, the processes underlying depletion of muscle mass and function have not been fully delineated. The impact of the systemic manifestations of COPD is substantial, and although many attempts have been made to elucidate the mechanisms underlying these manifestations, there are important questions, which remain to be answered. An increase in our understanding in this field will doubtless highlight potential therapeutic targets, and assist in guiding future therapeutic development.

RETRACTED: Effects of Omega-3 Polyunsaturated Fatty Acids on Inflammatory Markers in COPD

BACKGROUND

COPD, the fifth-leading cause of death worldwide, is characterized by chronic inflammation. However, no available agent can effectively cure this inflammation. A dietary supplement containing omega-3 polyunsaturated fatty acids (PUFAs) has anti-inflammatory effects. In this study, we hypothesized that nutritional support with omega-3 PUFA-rich diets may be useful for treating COPD, and we compared the clinical features and inflammatory mediator levels between the COPD patients who received an omega-3 PUFA-rich supplement and those who received a nonrich supplement.

METHODS

Sixty-four COPD patients received 400 kilocalories per day of an omega-3 PUFA-rich supplement (n-3 group) or an omega-3 PUFA-nonrich supplement (n-6 group) for 2 years. We prospectively investigated the clinical features of these patients and measured the levels of inflammatory mediators.

RESULTS

In 6-min walk testing, the dyspnea Borg scale and decrease of arterial oxygen saturation measured by pulse oximetry significantly improved in the n-3 group. Leukotriene B4 levels in serum and sputum and tumor necrosis factor-alpha and interleukin-8 levels in sputum decreased significantly in the n-3 group, while there was no significant change in the n-6 group. Two patients in the n-3 group and three patients in the n-6 group had mild diarrhea, and three patients in the n-3 group and three patients in the n-6 group had nausea; however, their symptoms were controllable and they improved with treatment. With multiple regression analysis, it was proved that the omega-3 PUFA-rich diet significantly contributed to the change in cytokine levels in this study.

CONCLUSION

We suggest nutritional support with an omega-3 PUFA-rich diet as a safe and practical method for treating COPD.

Systemic inflammatory response to exhaustive exercise in patients with chronic obstructive pulmonary disease

Systemic inflammation may be present in patients with chronic obstructive pulmonary disease (COPD). Exercise is known to elicit an inflammatory response. We hypothesized that the systemic inflammatory response to exercise might be exaggerated in COPD patients compared to healthy subjects. Sixteen COPD patients and 11 healthy subjects performed a maximal incremental bicycle test. Before and at maximal exercise arterial blood samples were taken to determine circulating catecholamines, (subsets of) leukocytes, acute phase proteins, creatine kinase and myoglobin. At rest, increased levels of norepinephrine and systemic inflammation were present in COPD. The response of catecholamines to exercise was lower in COPD patients (P<0.01), which in part was due to the lower maximal exercise capacity of these patients (P<0.01). Exercise-induced leukocytosis showed similar responses in both groups, but occurred at higher levels in COPD. Although patients had increased levels of CRP at rest (P<0.001), exercise did not affect acute phase proteins. No systemic signs of muscle damage were found. The present study shows that COPD patients are exposed to systemic inflammation that is intensified by exhaustive exercise. The inflammatory response in COPD is not exaggerated compared to healthy subjects but occurs at a higher level and is observed at lower external workload.

BMI and oral glucocorticoids as predictors of prognosis in COPD patients on long-term oxygen therapy

AIMS

The objectives of the study were to determine whether body mass index (BMI), and oral corticosteroid use predict survival and hospitalization in hypoxaemic chronic obstructive pulmonary disease (COPD) patients.

METHODS

The study was a prospective cohort study with analysis of a nationwide database (Danish Oxygen Register). We studied survival and hospitalization in 221 hypoxaemic COPD patients who were on long-term oxygen therapy (LTOT).

RESULTS

Low BMI was strongly associated with high mortality (P < 0.001). Maintenance treatment with steroids was only associated with higher mortality in overweight patients (BMI > or = 25 kg/m2), RR = 3.8 (1.4-10.5), P = 0.011. Whereas BMI had no influence on risk of any hospitalization in patients using oral steroids, high BMI was independently associated with reduced risk of any hospitalization in patients without oral steroids [the RR of any hospitalization for each 1 kg/m2 increase in BMI was 0.94 (CI: 0.90-0.99), P = 0.009]. Overall, the use of oral steroids was associated with increased risk of any hospitalization, RR = 1.7 (1.2-2.4), P = 0.002. This increase was especially pronounced in the group with BMI above 25 kg/m2, where steroid treatment increased the risk of any hospitalization with RR = 3.6 (1.5-8.7), P = 0.005.

CONCLUSIONS

In hypoxaemic patients on LTOT, low BMI is an independent risk factor of death and any hospitalization. Maintenance treatment with oral corticosteroids is associated with increased mortality and hospitalization in COPD patients with high BMI. Our findings suggest that loss of body weight should be avoided, and that oral corticosteroids should be used cautiously in patients on LTOT--especially those with high BMI. Further research on the role of changes in body composition as a prognostic factor is needed.

Pulmonary cachexia, systemic inflammatory profile, and the interleukin 1beta -511 single nucleotide polymorphism

BACKGROUND

Cachexia is common in chronic obstructive pulmonary disease (COPD) and is thought to be linked to an enhanced systemic inflammatory response.

OBJECTIVE

We investigated differences in the systemic inflammatory profile and polymorphisms in related inflammatory genes in COPD patients.

DESIGN

A cross-sectional study was performed in 99 patients with COPD (Global Initiative for Chronic Obstructive Lung Disease stages II-IV), who were stratified by cachexia based on fat-free mass index (FFMI; in kg/m2: <16 for men and <15 for women) and compared with healthy control subjects (HCs). Body composition was determined by bioelectrical impedance analysis. Plasma concentrations and gene polymorphisms of interleukin 1beta (IL-1beta -511), IL-6 (IL-6 -174), and the tumor necrosis factor system (TNF-alpha -308 and lymphotoxin-alpha +252) were determined. Plasma C-reactive protein, leptin, and urinary pseudouridine (as a marker of cellular protein breakdown) were measured.

RESULTS

Fat mass, leptin, and pseudouridine were significantly different (P < 0.001) between noncachectic patients (NCPs) and cachectic patients (CPs: n = 35); the systemic inflammatory cytokine profile was not. NCPs had a body compositional shift toward a lower fat-free mass and a higher fat mass compared with HCs. CPs and NCPs had a greater systemic inflammatory response (P < 0.05) than did HCs, as reflected in C-reactive protein, soluble TNF-R75, and IL-6 concentrations. The overall distribution of the IL-1beta -511 polymorphism was significantly different between the groups (P < 0.05).

CONCLUSIONS

In COPD patients, who are characterized by an elevated systemic inflammatory response, cachexia is not discriminatory for the extent of increase in inflammatory status. This study, however, indicates a potential influence of genetic predisposition on the cachexia process.

Nutritional management of the patient with chronic obstructive pulmonary disease

The prevalence and prognostic importance of malnutrition in chronic obstructive pulmonary disease (COPD), the factors that contribute to development of nutritional depletion, and the available evidence regarding effects of nutrition support in these patients are the subjects of this review. Nutritional depletion, as indicated by weight loss and loss of lean body mass, is a common complication of advanced COPD (particularly, but not limited to, the emphysematous type). Low body weight or recent weight loss and in particular depleted lean body mass in patients with COPD have been shown to be independent predictors of mortality, outcomes after acute exacerbations, hospital admission rates, and need for mechanical ventilation. The factors thought to contribute to nutritional depletion in these patients include elevated resting and activity-related energy expenditure, reduced dietary intake relative to resting energy expenditure, accelerated negative nitrogen balance, particularly during acute exacerbations of COPD, medication effects, and perhaps most importantly an elevated systemic inflammatory response. Studies to date suggest that, although it can help limit weight loss and negative energy balance in these patients, the effect of nutritional supplementation alone on clinically significant outcomes such as pulmonary function and exercise capacity is minimal. However, nutritional supplementation may have a role in the management of COPD when provided as part of an integrated rehabilitation program incorporating a structured exercise component as an anabolic stimulus.

Mid-Arm Muscle Area Is a Better Predictor of Mortality Than Body Mass Index in COPD

BACKGROUND

A low body mass index (BMI) has been shown to be an independent indicator of poor prognosis in patients with COPD. However, some studies suggest that muscle mass depletion (MD) is the main factor responsible for the negative effects attributable to malnutrition.

STUDY OBJECTIVE

To evaluate the prognostic influence of MD estimated from anthropometric parameters.

DESIGN AND MEASUREMENTS

Mortality was studied in a prospective cohort of 96 male patients with COPD (average age, 69 +/- 9 years; FEV1 percentage of predicted, 44 +/- 18% [ +/- SD]) followed up for 3 years, with an evaluation of the prognostic influence of the following anthropometric parameters: BMI, mid-arm muscle area (MAMA), and fat-free mass index. Other risk factors were also analyzed, such as age, comorbidity (Charlson index), basal dyspnea index, the St. George's Respiratory Questionnaire score, the number of hospital admissions in the year prior to nutritional evaluation, the number of hospital admissions in the year immediately after nutritional evaluation (Hpost), spirometry, and blood gases.

RESULTS

In the multivariate study, Pa(CO2) (p = 0.003; hazard ratio, 1.08), Hpost (p = 0.005, hazard ratio, 4.63), and a MAMA value less than or equal to percentile 25 of the reference value (p25) [p = 0.025; hazard ratio, 3.78] were found to be independent indicators of poor prognosis. Respiratory mortality after 12, 24, and 36 months in the patients with MAMA < or = p25 was 12.1%, 31.4%, and 39.2%, respectively, vs 5.9%, 7.9%, and 13% in the group of patients without MD (p = 0.006). In normal-weight or overweight patients, MAMA < or = p25 increased the risk of mortality 3.4-fold (p = 0.032).

CONCLUSIONS

MD is a better predictor of mortality than BMI in patients with COPD, fundamentally in normal-weight or overweight patients. The prognostic influence of MD can be estimated indirectly by determining the MAMA, an inexpensive, simple, and rapidly obtained anthropometric measure.

Altered interorgan response to feeding in patients with chronic obstructive pulmonary disease

BACKGROUND

Previously, we reported increased values for whole-body protein turnover in patients with chronic obstructive pulmonary disease (COPD) in the postabsorptive state.

OBJECTIVE

The objective was to investigate whether intake of a carbohydrate-protein meal influences whole-body protein turnover differently in COPD patients and control subjects.

DESIGN

Eight normal-weight patients with moderate COPD and 8 healthy control subjects were examined in the postabsorptive state and after 2 h of repeatedly ingesting a maltodextrin casein-based protein meal (0.02 g x kg body wt(-1) x 20 min(-1)). Combined simultaneous, continuous, intravenous infusion of L-[ring-2H5]-phenylalanine and L-[ring-2H2]-tyrosine tracer and oral repeated ingestion of 1-13C-phenylalanine were performed to measure whole-body protein synthesis (WbPS) and first-pass splanchnic extraction of phenylalanine. Endogenous rate of appearance of phenylalanine as the measure of whole-body protein breakdown (WbPB) and netWbPS was calculated as WbPS--WbPB. Arterialized venous blood was sampled for amino acid enrichment and concentration analyses.

RESULTS

Feeding induced an increase in WbPS and a reduction in WbPB. The reduction in WbPB was larger in the COPD group than in the control group (P < 0.05) and was related to the lower splanchnic extraction of phenylalanine in the patients. Consequently, netWbPS increased more after feeding in the COPD group than in the control group (P < 0.05).

CONCLUSION

Feeding induces more protein anabolism in normal-weight patients with moderate COPD than in healthy control subjects. This is probably because these COPD patients are characterized by an adaptive interorgan response to feeding to prevent or delay weight loss at this disease stage.

Nutritional status, dietary energy intake and the risk of exacerbations in patients with chronic obstructive pulmonary disease (COPD)

Loss of body weight, as a result of imbalance between increased energy demand and/or reduced dietary intake, is a common problem in patients with COPD. The aim of this investigation was to examine the relationship between nutritional intake, change in body weight and the risk of exacerbation in patients with COPD. The study comprised 41 patients who were hospitalised because of an exacerbation of COPD. The follow-up period was 12 months. Weight, height and lung function were measured at baseline. At the 12-month follow-up, weight change and current weight were assessed by an interview and nutritional intake was recorded in a food diary for 7 days. An acute exacerbation was defined as having been admitted to hospital and/or making an emergency visit to hospital, due to COPD during the follow-up period. At baseline, 24% of the patients were underweight (body mass index (BMI)<20 kg/m2), 46% were of normal weight (BMI 20-25 kg/m2) and 29% were overweight (BMI>25 kg/m2). Energy intake was lower than the calculated energy demand for all groups. During the follow-up period, 24 of the 41 patients had an exacerbation. A low BMI at inclusion and weight loss during the follow-up period were independent risk factors for having an exacerbation (P=0.003 and 0.006, respectively). We conclude that, in patients who are hospitalised because of COPD, underweight and weight loss during the follow-up period are related to a higher risk of having new exacerbations.

A novel polymorphism in secretory phospholipase A2-IID is associated with body weight loss in chronic obstructive pulmonary disease

RATIONALE

Chronic and systemic inflammation, a potential cause of body weight loss in patients with chronic obstructive pulmonary disease (COPD), may be associated with the proinflammatory properties of secretory phospholipases A2 (sPLA2s), especially the group II subfamily sPLA2s.

OBJECTIVES

We tested our hypothesis that the individual susceptibility to body weight loss in patients with COPD is attributed to the genetic variances of this sPLA2 gene region.

METHODS

A total of 12 single nucleotide polymorphisms (SNPs) encompassing the sPLA2 gene region were determined in 276 male patients with COPD.

MEASUREMENTS AND MAIN RESULTS

We first analyzed our patients whose body mass index (BMI) was at the bottom 100 (BMI, 17.13 +/- 1.29 kg/m2) and at the top 100 (23.83 +/- 1.98) in relation to SNPs. Both the Fisher's exact test (odds ratio, 2.36; 95% confidence interval, 1.34-4.18; p = 0.004) and logistic regression analysis (odds ratio, 2.10; 95% confidence interval, 1.13-3.90; p = 0.019) showed statistical significance between one SNP (National Center for Biotechnology Information SNP reference: rs584367) and the reduction of BMI in the recessive model in patients with COPD. Using all the patients, a significant difference between the values of BMI (log transformed) of the mutant group (CT + TT) and that of the nonmutant group (CC) of this SNP (mean [SE], 1.293 [0.005] vs. 1.317 [0.006]; p = 0.003) was found after adjustment for age, smoking habit, and pulmonary function (analysis of covariance). Importantly, this SNP caused a change in amino acids in sPLA2-IID protein (Gly80Ser).

CONCLUSIONS

These results suggest that sPLA2-IID may be one of the susceptibility genes that contribute to body weight loss in patients with COPD.

Post-exercise heart rate recovery and mortality in chronic obstructive pulmonary disease

Abnormal heart rate recovery (HRR) after exercise, a marker of cardiac autonomic dysfunction, is associated with poor prognosis in various populations. As chronic obstructive pulmonary disease (COPD) is associated with cardiac autonomic dysfunction, we tested the hypothesis that patients with COPD have a lower HRR than healthy people, and evaluated whether a delay in HRR is associated with an increased risk of mortality in COPD. The records of 147 COPD patients were reviewed (65.1+/-9.1 years, mean+/-sd, 42 women/105 men, forced expiratory volume in 1s (FEV1): 42+/-15% predicted) and compared to 25 healthy subjects (61.6+/-4.5 years, 5 women/20 men, FEV1: 100+/-14% predicted) during recovery after an exercise test. Heart rate was measured at peak exercise and at 1-min recovery, the difference between the two being defined as HRR (11+/-9 beats in COPD patients vs. 20+/-9 beats in healthy subjects, P < 0.0001). During a mean follow-up of 43.1+/-22.0 months, 32 patients died. Abnormal HRR (14 beats) was a strong predictor of mortality in COPD patients (adjusted hazard ratio: 5.12, 95% CI [1.54-17.00]). In conclusion, COPD patients have a lower HRR than healthy subjects, and have a worse prognosis when presenting abnormal HRR.

Preparing Nurses for the Global Pandemic of Chronic Obstructive Pulmonary Disease

PURPOSE

To raise awareness of the global pandemic of chronic obstructive pulmonary disease (COPD), its multiple underlying causes, and how to fight it, with particular attention to needs in nursing education.

METHODS

Integrative review of the literature.

FINDINGS

The main underlying causes of COPD are both individual and environmental factors, and the disease usually results from an interaction between these two factors. The prevalence of COPD is highest in countries where cigarette smoking has been, or still is, very common, and it is lowest in countries where smoking is less common, or total tobacco consumption per person is low. COPD is to some extent a preventable disease especially by preventing exposure to tobacco smoke and to occupational dusts and chemicals including vapours, irritants, fumes, and indoor and outdoor air pollution. The main implication for nurses and nursing curricula is to expand the focus from the individual to include population-based intervention programmes.

CONCLUSIONS

Addressing the underlying causes of COPD and providing appropriate interventions are within the scope of nursing practice and responsibility. Changes in nursing education are needed for nurses to be able to address the COPD pandemic.

Abdominal muscle and quadriceps strength in chronic obstructive pulmonary disease

BACKGROUND

Quadriceps muscle weakness is common in chronic obstructive pulmonary disease (COPD) but is not observed in a small hand muscle (adductor pollicis). Although this could be explained by reduced activity in the quadriceps, the observation could also be explained by anatomical location of the muscle or fibre type composition. However, the abdominal muscles are of a similar anatomical and fibre type distribution to the quadriceps, although they remain active in COPD. Cough gastric pressure is a recently described technique that assesses abdominal muscle (and hence expiratory muscle) strength more accurately than traditional techniques. A study was undertaken to test the hypothesis that more severe weakness exists in the quadriceps than in the abdominal muscles of patients with COPD compared with healthy elderly controls.

METHODS

Maximum cough gastric pressure and quadriceps isometric strength were measured in 43 patients with stable COPD and 25 healthy elderly volunteers matched for anthropometric variables.

RESULTS

Despite a significant reduction in mean quadriceps strength (29.9 kg v 41.2 kg; 95% CI -17.9 to -4.6; p = 0.001), cough gastric pressure was preserved in patients with COPD (227.3 cm H(2)O v 204.8 cm H(2)O; 95% CI -5.4 to 50.6; p = 0.11).

CONCLUSIONS

Abdominal muscle strength is preserved in stable COPD outpatients in the presence of quadriceps weakness. This suggests that anatomical location and fibre type cannot explain quadriceps weakness in COPD. By inference, we conclude that disuse and consequent deconditioning are important factors in the development of quadriceps muscle weakness in COPD patients, or that activity protects the abdominal muscles from possible systemic myopathic processes.

Increased length of hospital stay in underweight and overweight patients at hospital admission: a controlled population study

BACKGROUND

Reduced lean tissue as well as high fat mass may be independent nutritional risk factors resulting in increased length of hospital stay (LOS). This controlled population study (1707 patients, 1707 volunteers) aimed to evaluate the association between LOS in Geneva and Berlin patients at hospital admission and high fat mass index (FMI, kg/m2) and low fat-free mass index (FFMI, kg/m2), and the respective value of body mass index (BMI) and of FFMI and FMI for nutritional assessment.

METHODS

Patients (891 men, 816 women) were prospectively recruited at hospital admission and compared to gender-, age- and height-matched healthy volunteers. Fat-free mass and fat mass, determined at admission by 50 kHz-bioelectrical impedance analysis, were expressed as indices (FFMI and FMI-kg/m2) to normalize for height. Patients were classified in four groups: normal, low FFMI, high FMI, or low FFMI and high FMI. Logistic regressions were used to determine the association between body composition and LOS.

RESULTS

Higher FMI and lower FFMI were found in patients at hospital admission than in sex- and age-matched healthy volunteers. Low FFMI, high FMI, and low FFMI/high FMI combined, adjusted for age, were all significantly associated with longer LOS (high FFMI: 1-5 days OR 2.4, CI 2.0-2.9; 6-10 days OR 2.3, CI 1.8-3.0; 11 days OR 2.8, CI 2.2-3.5); low FMI: 1-5 days OR 1.9, CI 1.6-2.2; 6-10 days OR 2.7, CI 2.0-3.5, 11 days OR 2.1, CI 1.7-2.7; low FFMI/high FMI: 1-5 days OR 7.8, CI 5.3-11.4; 6-10 days OR 13.6, CI 7.8-23.5, 11 days OR 11.8, CI 7.0-19.8).

CONCLUSION

Increased LOS is associated with adiposity (high FMI) and low muscle mass (low FFMI). The current study shows that both depletion of lean tissue and excess of fat mass negatively affect the LOS. Finally, we found that excess fat mass reduces the sensitivity of BMI to detect nutritional depletion.

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.

Low staffing level is associated with malnutrition in long-term residential care homes

OBJECTIVE

To determine if staffing level is associated with poor nutrition in the long-term residential care setting, adjusting for other confounding factors.

DESIGN

Cross-sectional survey.

SETTING

In total, 14 residential care facilities in Hong Kong, stratified by nature (government subvention or for-profit) to reflect the overall proportion in Hong Kong.

SUBJECTS

A total of 1914 subjects were assessed, using the Resident Assessment Instrument (RAI) 2.0. The response rate was 95% (1820 subjects), of which 1699 subjects had complete nutritional information.

INTERVENTION

Body mass index (BMI) was calculated by weighing and height measurement, and arm span was used if the subject could not stand. Subjects who were receiving parenteral or enteral nutrition via nasogastric of enterostomy tubes were excluded. A history of weight loss of 5% in the past month or 10% in the past 6 months, leaving 25% of food uneaten, and BMI < 18.5 kg/m(2) were examined as nutritional indicators. Association with age, gender, functional disability, oral problems, taste problems, presence of physical diseases and psychological well-being was examined using chi(2)-test, and multiple logistic regression.

RESULTS

In all, 26% of residents had a BMI < 18.5 kg/m(2), with a higher prevalence in the for-profit homes. History of weight loss and the record that 25% of food was left uneaten were poor indicators of low BMI. Multivariate analysis showed that having chronic obstructive airways disease, requiring help with feeding, being female, older age, were factors associated with an increased risk of poor nutrition, while being independent in activities of daily living and higher staff levels were associated with a reduced risk.

CONCLUSION

Poor nutrition is a persistent problem in the long-term care setting, and inadequate staffing levels may be a reversible cause. However, resource limitations may render efforts at improvement difficult.

SPONSORSHIP

SK Yee Memorial Fund.

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.

Diminution de la fonction musculaire dynamique dans la BPCO : étude préliminaire

BACKGROUND

The aim of the study was to investigate dynamic muscle function during all-out exercise in patients with chronic obstructive pulmonary disease (COPD) and to observe the relationship between body composition and skeletal muscle function.

MATERIAL AND METHODS

Eight patients (FEV1: 53.0 +/- 9.3%) performed three tests i) three maximal sprints on a specialised cycle ergometer to assess individual Velocity-Power relationship, and measure of maximal anaerobic power (Pmax), optimal velocity (Vopt), ii) assessment of whole-body and subregional fat-free mass (FFM) by dual-energy X-ray absorptiometry, iii) determination of maximal oxygen consumption.

RESULTS

Maximal anaerobic power and corresponding optimal velocity were 3.9 +/- 1.6 W x kg(-1) et 85.4 +/- 17.0 rpm, respectively. COPD showed a 30% decrease of Pmax, compared to healthy older subjects (5.6 +/- 1.1 W x kg(-1)). No such difference was observed with Vopt (85.4 +/- 13.0 rpm vs 86.8 +/- 9.5 rpm). Pmax and Vopt were highly significantly correlated with lower extremities FFM, but not with airflow obstruction parameters.

CONCLUSION

Our results showed that skeletal muscle function parameters such as Pmax and Vopt could characterise peripheral muscle weakness of COPD.

Associated loss of fat-free mass and bone mineral density in chronic obstructive pulmonary disease

We hypothesized that in patients with chronic obstructive pulmonary disease, loss of fat-free mass (FFM) and loss of bone mineral density (BMD) were related to (1) each other and may be clinically inapparent, (2) urinary markers of cellular and bone collagen protein breakdown, and (3) severity of lung disease. Eight-one patients and 38 healthy subjects underwent dual-energy X-ray absorptiometry to determine body composition and BMD. Urinary protein breakdown markers, inflammatory mediators, and their soluble receptors were determined. Thirty-three patients had a low fat-free mass index (kg/m(2)), 17 of whom had a normal body mass index. Thirty-two percent of patients (13% of healthy subjects) had osteoporosis at the hip or lumbar spine. The marker of cellular protein breakdown was elevated in patients and related to lung disease severity and body composition. The marker of bone collagen breakdown was greater in patients with osteoporosis. Inflammatory mediators were elevated in patients. Loss of FFM and loss of BMD were related, occurred commonly, and could be subclinical in patients with chronic obstructive pulmonary disease. Loss of both was greatest with severe lung disease. Increased excretion of cellular and bone collagen protein breakdown products in those with low FFM and BMD indicates a protein catabolic state in these patients.

Management of severe COPD

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide, and the burden of the disorder will continue to increase over the next 20 years despite medical intervention. Apart from smoking cessation, no approach or agent affects the rate of decline in lung function and progression of the disease. Especially in the later phase, COPD is a multicomponent disorder, and various integrated intervention strategies are needed as part of the optimum management programme. This seminar describes largely non-pharmacological interventions aimed at improving health status and function of disabled patients. Exacerbations become progressively more troublesome as baseline lung function declines, commonly necessitating hospital admission and associated with the development of acute respiratory failure.

[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.

Burden and clinical features of chronic obstructive pulmonary disease (COPD)

Chronic obstructive pulmonary disease (COPD) is a major cause of chronic morbidity and mortality and represents a substantial economic and social burden throughout the world. It is the fifth leading cause of death worldwide and further increases in its prevalence and mortality are expected in the coming decades. The substantial morbidity associated with COPD is often underestimated by health-care providers and patients; likewise, COPD is frequently underdiagnosed and undertreated. COPD develops earlier in life than is usually believed. Tobacco smoking is by far the major risk for COPD and the prevalence of the disease in different countries is related to rates of smoking and time of introduction of cigarette smoking. Contribution of occupational risk factors is quite small, but may vary depending on a country's level of economic development. Severe deficiency for alpha-1-antitrypsin is rare and the impact of other genetic factors on the prevalence of COPD has not been established. COPD should be considered in any patient presenting with cough, sputum production, or dyspnoea, especially if an exposure to risk factors for the disease has been present. Clinical diagnosis needs to be confirmed by standardised spirometric tests in the presence of not-fully-reversible airflow limitation. COPD is generally a progressive disease. Continued exposure to noxious agents promotes a more rapid decline in lung function and increases the risk for repeated exacerbations. Smoking cessation is the only intervention shown to slow the decline. If exposure is stopped, the disease may still progress due to the decline in lung function that normally occurs with aging, and some persistence of the inflammatory response.

C-Reactive Protein and Body Mass Index Predict Outcome in End-Stage Respiratory Failure

STUDY OBJECTIVE

To determine the predictive factors of morbidity and mortality in patients with end-stage respiratory disease.

DESIGN

Prospective, multicenter cohort study.

SETTING

Thirteen outpatient chest clinics within the Association Nationale de Traitement à Domicile de l'Insuffisance Respiratoire.

PARTICIPANTS

Stable adult patients with chronic respiratory failure receiving long-term oxygen therapy and/or home mechanical ventilation (n = 446; 182 women and 264 men; aged 68.5 +/- 12.1 years [+/- SD]); Respiratory diseases were COPD in 42.8%, restrictive disorders in 36.3%, mixed respiratory failure in 13.5%, and bronchiectasis in 7.4%. Recruitment was performed during the yearly examination. Patients with neuromuscular diseases and sleeping apnea were excluded.

MEASUREMENTS AND RESULTS

Hospitalization days and survival were recorded during a follow-up of 14.3 +/- 5.6 months. Body mass index (BMI), serum albumin, and transthyretin levels were considered for their predictive value of outcome, together with demographic data, underlying respiratory disease, respiratory function, hemoglobin, C-reactive protein, smoking habits, oral corticosteroid use, and antibiotic treatment courses. Overall, 1.8 +/- 1.7 hospitalizations (cumulative stay, 17.6 +/- 27.1 days) were observed in 254 of 446 patients (57%). Independent predictors of hospitalization were oral corticosteroids, FEV(1), and plasma C-reactive protein. One-year and 2-year cumulative survivals were 93% and 69%, respectively. Plasma C-reactive protein, BMI, Pao(2) on room air, and oral corticosteroids independently predicted survival in multivariate analysis.

CONCLUSION

Besides established prognosis factors such as FEV(1) and Pao(2), nutritional depletion as assessed by BMI and overall systemic inflammation as estimated by C-reactive protein appear as major determinants of hospitalization and death risks whatever the end-stage respiratory disease. BMI and C-reactive protein should be included in the monitoring of chronic respiratory failure. Oral corticosteroids as maintenance treatment in patients with end-stage respiratory disease are an independent risk factor of death, and should be avoided in most cases.