Impact of nutritional support on functional status during an acute exacerbation of chronic obstructive pulmonary disease

Improvement of Lung Function by Micronutrient Supplementation in Patients with COPD: A Systematic Review and Meta-Analysis

BACKGROUND

A healthy, well-balanced diet plays an essential role in respiratory diseases. Since micronutrient deficiency is relatively common in patients with chronic obstructive pulmonary disease (COPD), micronutrient supplementation might have the beneficial health effects in those patients. This systematic review and meta-analysis aimed to demonstrate the impact of micronutrient supplementation on the lung function of patients with COPD.

METHODS

The PubMed, Cochrane Library, and Web of Science databases were searched from their corresponding creation until February 2024. Search terms included 'chronic obstructive pulmonary disease', 'COPD', 'micronutrients', 'dietary supplements', 'vitamins', 'minerals', and 'randomized controlled trials'. Meta-analysis was performed to evaluate the effects of micronutrient supplementation alone or complex on lung function in patients with COPD.

RESULTS

A total of 43 RCTs fulfilled the inclusion criteria of this study. Meta-analysis revealed that vitamin D supplementation could significantly improve FEV1% (WMDdifferences between baseline and post-intervention (de): 6.39, 95% CI: 4.59, 8.18, p < 0.01; WMDpost-intervention indicators (af): 7.55, 95% CI: 5.86, 9.24, p < 0.01) and FEV1/FVC% (WMDde: 6.88, 95%CI: 2.11, 11.65, WMDaf: 7.64, 95% CI: 3.18, 12.10, p < 0.001), decrease the odds of acute exacerbations, and improve the level of T-cell subsets, including CD3+%, CD4+%, CD8+%, and CD4+/CD8+% (all p < 0.01). The effects of compound nutrients intervention were effective in improving FEV1% (WMDde: 8.38, 95%CI: 1.89, 14.87, WMDaf: 7.07, 95%CI: -0.34, 14.48) and FEV1/FVC% (WMDde: 7.58, 95% CI: 4.86, 10.29, WMDaf: 6.00, 95% CI: 3.19, 8.81). However, vitamin C and vitamin E supplementation alone had no significant effects on lung function (p > 0.05).

CONCLUSIONS

Micronutrient supplementation, such as vitamin D alone and compound nutrients, has improved effect on the lung function of patients with COPD. Therefore, proper supplementation with micronutrients would be beneficial to stabilize the condition and restore ventilation function for COPD patients.

Effectiveness of Dietary Counselling With or Without Nutritional Supplementation in Hospitalised Patients who are Malnourished or at Risk of Malnutrition - A Systematic Review and Meta-Analysis

Background

Nutrition support is associated with improved survival and nonelective hospital readmission rates among malnourished medical inpatients; however, limited evidence supporting dietary counseling is available. We intend to determine the effect of dietary counseling with or without oral nutrition supplementation (ONS), compared with standard care, on hospitalized adults who are malnourished or at risk of malnutrition.

Methods

We searched MEDLINE/PubMed, CINAHL, Embase, Scopus, The Cochrane Library, and Google Scholar for studies listed from January 1, 2011, to August 31, 2021. Meta‐analysis was performed to obtain pooled risk ratios (RRs) and 95% CIs to estimate the effect. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was used to assess the certainty of the evidence.

Results

Sixteen studies were identified. Compared with standard care, dietary counseling with or without ONS probably does not reduce inpatient rates of 30‐day mortality (RR = 1.24; 0.60–2.55; I² = 45%; P = 0.56; moderate certainty), slightly reduces 6‐month mortality (RR = 0.83; 0.69–1.00; I² = 16%; P = 0.06; high certainty), reduces complications (RR = 0.85; 0.73–0.98; I² = 0%; P = 0.03; high certainty), and may slightly reduce readmission (RR = 0.83; 0.66–1.03; I² = 55%; P = 0.10; low certainty) but may not reduce length of stay (mean difference: −0.75 days; −1.66‐0.17; I² = 70%; P = 0.11; low certainty). Intervention may result in slight improvements in nutrition status/intake and weight/body mass index (low certainty).

Conclusions

There is an increase in the certainty of evidence regarding the positive impact of dietary counseling on outcomes. Future studies should standardize and provide details/frequencies of counseling methods and ONS adherence to determine dietary counseling effectiveness.

Increased energy and/or protein intake improves anthropometry and muscle strength in chronic obstructive pulmonary disease patients: a systematic review with meta-analysis on randomised controlled clinical trials

Compromised nutritional status is associated with a poor prognosis in chronic obstructive pulmonary disease (COPD) patients. However, the impact of nutritional support in this group of patients is controversial. The present study systematically reviewed the effect of energy and or protein supplements or food fortification on anthropometry and muscle strength of COPD patients. We searched MEDLINE (PubMed), EMBASE, Cochrane Library and Scopus for all published randomised clinical trials without language restriction up to May 2021. Three reviewers performed study selection and data extraction independently. We judged the risk of bias by RoB 2 and the certainty of evidence by the GRADE approach. We included thirty-two randomised controlled trials and compiled thirty-one of them (1414 participants) in the random-effects model meta-analyses. Interventions were energy and/or protein oral nutritional supplements or food fortification added to the diet for at least one week. Pooled analysis revealed that nutritional interventions increased body weight (muscle circumference (MD) = 1·44 kg, 95 % CI 0·81, 2·08, I2 = 73 %), lean body mass (standardised mean difference (SMD) = 0·37; 95 % CI 0·15, 0·59, I2 = 46 %), midarm muscle circumference (MD = 0·29 mm2, 95 % CI 0·02, 0·57, I2 = 0 %), triceps skinfold (MD = 1·09 mm, 95 % CI 0·01, 2·16, I2 = 0 %) and handgrip strength (SMD = 0·39, 95 % CI 0·07, 0·71, I2 = 62 %) compared with control diets. Certainty of evidence ranged from very low to low, and most studies were judged with some concerns or at high risk of bias. This meta-analysis revealed, with limited evidence, that increased protein and/or energy intake positively impacts anthropometric measures and handgrip strength of COPD patients.

A review on the Role of Oral Nutritional Supplements in Chronic Obstructive Pulmonary Disease

Due to the high smoking rate in developing countries and the rising aging population in high-income countries, the global prevalence of chronic obstructive pulmonary disease (COPD), estimated to be 11.7%, is increasing and is the third-leading cause of mortality. COPD is likely to be present in elderly individuals with impaired gastro-enteric functions. Gastrointestinal congestion, dyspnea, and anxiety are pathophysiological characteristics of COPD, contributing to poor appetite, reduced dietary intake, and high-energy expenditure. These factors are implicated in the progression of malnutrition in COPD patients. Malnutrition is detrimental to lung functions and is associated with an increased risk of infection, exacerbation and mortality, and a longer duration of hospitalization. Therefore, nutritional support to treat malnutrition in COPD patients is very vital. Oral nutritional supplements (ONS) may hold the key to COPD treatment. To clarify this statement, we review current evidence for ONS in COPD patients to benefit from clinical outcomes.

Dietary advice with or without oral nutritional supplements for disease-related malnutrition in adults

BACKGROUND

Disease-related malnutrition has been reported in 10% to 55% of people in hospital and the community and is associated with significant health and social-care costs. Dietary advice (DA) encouraging consumption of energy- and nutrient-rich foods rather than oral nutritional supplements (ONS) may be an initial treatment.

OBJECTIVES

To examine evidence that DA with/without ONS in adults with disease-related malnutrition improves survival, weight, anthropometry and quality of life (QoL).

SEARCH METHODS

We identified relevant publications from comprehensive electronic database searches and handsearching. Last search: 01 March 2021.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of DA with/without ONS in adults with disease-related malnutrition in any healthcare setting compared with no advice, ONS or DA alone.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study eligibility, risk of bias, extracted data and graded evidence.

MAIN RESULTS

We included 94, mostly parallel, RCTs (102 comparisons; 10,284 adults) across many conditions possibly explaining the high heterogeneity.  Participants were mostly older people in hospital, residential care and the community, with limited reporting on their sex. Studies lasted from one month to 6.5 years.  DA versus no advice - 24 RCTs (3523 participants) Most outcomes had low-certainty evidence. There may be little or no effect on mortality after three months, RR 0.87 (95% confidence interval (CI) 0.26 to 2.96), or at later time points. We had no three-month data, but advice may make little or no difference to hospitalisations, or days in hospital after four to six months and up to 12 months. A similar effect was seen for complications at up to three months, MD 0.00 (95% CI -0.32 to 0.32) and between four and six months. Advice may improve weight after three months, MD 0.97 kg (95% CI 0.06 to 1.87) continuing at four to six months and up to 12 months; and may result in a greater gain in fat-free mass (FFM) after 12 months, but not earlier. It may also improve global QoL at up to three months, MD 3.30 (95% CI 1.47 to 5.13), but not later. DA versus ONS - 12 RCTs (852 participants) All outcomes had low-certainty evidence. There may be little or no effect on mortality after three months, RR 0.66 (95% CI 0.34 to 1.26), or at later time points. Either intervention may make little or no difference to hospitalisations at three months, RR 0.36 (95% CI 0.04 to 3.24), but ONS may reduce hospitalisations up to six months. There was little or no difference between groups in weight change at three months, MD -0.14 kg (95% CI -2.01 to 1.74), or between four to six months. Advice (one study) may lead to better global QoL scores but only after 12 months. No study reported days in hospital, complications or FFM. DA versus DA plus ONS - 22 RCTs (1286 participants) Most outcomes had low-certainty evidence. There may be little or no effect on mortality after three months, RR 0.92 (95% CI 0.47 to 1.80) or at later time points. At three months advice may lead to fewer hospitalisations, RR 1.70 (95% CI 1.04 to 2.77), but not at up to six months. There may be little or no effect on length of hospital stay at up to three months, MD -1.07 (95% CI -4.10 to 1.97). At three months DA plus ONS may lead to fewer complications, RR 0.75 (95% CI o.56 to 0.99); greater weight gain, MD 1.15 kg (95% CI 0.42 to 1.87); and better global QoL scores, MD 0.33 (95% CI 0.09 to 0.57), but this was not seen at other time points. There was no effect on FFM at three months. DA plus ONS if required versus no advice or ONS - 31 RCTs (3308 participants) Evidence was moderate- to low-certainty. There may be little or no effect on mortality at three months, RR 0.82 (95% CI 0.58 to 1.16) or at later time points. Similarly, little or no effect on hospitalisations at three months, RR 0.83 (95% CI 0.59 to 1.15), at four to six months and up to 12 months; on days in hospital at three months, MD -0.12 (95% CI -2.48 to 2.25) or for complications at any time point. At three months, advice plus ONS probably improve weight, MD 1.25 kg (95% CI 0.73 to 1.76) and may improve FFM, 0.82 (95% CI 0.35 to 1.29), but these effects were not seen later. There may be little or no effect of either intervention on global QoL scores at three months, but advice plus ONS may improve scores at up to 12 months. DA plus ONS versus no advice or ONS - 13 RCTs (1315 participants) Evidence was low- to very low-certainty. There may be little or no effect on mortality after three months, RR 0.91 (95% CI 0.55 to 1.52) or at later time points. No study reported hospitalisations and there may be little or no effect on days in hospital after three months, MD -1.81 (95% CI -3.65 to 0.04) or six months. Advice plus ONS may lead to fewer complications up to three months, MD 0.42 (95% CI 0.20 to 0.89) (one study). Interventions may make little or no difference to weight at three months, MD 1.08 kg (95% CI -0.17 to 2.33); however, advice plus ONS may improve weight at four to six months and up to 12 months. Interventions may make little or no difference in FFM or global QoL scores at any time point.

AUTHORS' CONCLUSIONS

We found no evidence of an effect of any intervention on mortality. There may be weight gain with DA and with DA plus ONS in the short term, but the benefits of DA when compared with ONS are uncertain. The size and direction of effect and the length of intervention and follow-up required for benefits to emerge were inconsistent for all other outcomes.  There were too few data for many outcomes to allow meaningful conclusions. Studies focusing on both patient-centred and healthcare outcomes are needed to address the questions in this review.

Nutritional trials using high protein strategies and long duration of support show strongest clinical effects on mortality.: Results of an updated systematic review and meta-analysis

BACKGROUND

There is increasing evidence from randomized-controlled trials demonstrating that nutritional support improves clinical outcomes in the population of malnourished medical inpatients. We investigated associations of trial characteristics including clinical setting, duration of intervention, individualization of nutritional support and amount of energy and protein, and effects on clinical outcomes in an updated meta-analysis.

METHODS

We searched Cochrane Library, MEDLINE and EMBASE, from inception to December 15, 2020. Randomized-controlled trials investigating the effect of oral and enteral nutritional support interventions, when compared to usual care, on clinical outcomes of malnourished non-critically ill medical inpatients were included. Two reviewers independently extracted data and assessed risk of bias. The primary endpoint was all cause-mortality within 12-months.

RESULTS

We included 29 randomized-controlled trials with a total of 7,166 patients. Heterogeneity across RCTs was high, with overall moderate study quality and mostly moderate or unclear risk of bias. Overall, there was an almost 30%-reduction in mortality in patients receiving nutritional support compared to patients not receiving nutritional support (253/2960 [8.5%] vs. 336/2976 [11.3%]) with an odds ratio of 0.72 (95% CI 0.57 to 0.91, p = 0.006). The most important predictors for the effect of nutritional trials on mortality were high protein strategies (odds ratio 0.57 vs. 0.93, I² = 86.3%, p for heterogenity = 0.007) and long-term nutritional interventions (odds ratio 0.53 vs. 0.85, I² = 76.2%, p for heterogenity = 0.040). Nutritional support also reduced unplanned hospital readmissions and length of hospital stay.

CONCLUSIONS

There is increasing evidence from randomized trials showing that nutritional support significantly reduces mortality, unplanned hospital readmissions and length of stay in medical inpatients at nutritional risk, despite heterogeneity and varying methodological quality among trials. Trials with high-protein strategies and long-lasting nutritional support interventions were most effective.

Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide and results in an economic and social burden that is both substantial and increasing. The natural history of COPD is punctuated by exacerbations, which have major short- and long-term implications on the patient and health care system. Evidence-based guidelines stipulate that early detection and prompt treatment of exacerbations are essential to ensure optimal outcomes and to reduce the burden of COPD. In this review, we provide a concise overview of COPD exacerbations and their risk factors and etiology (infection vs noninfectious), outlining the initial evaluation, triaging, and current management including invasive and noninvasive ventilation, in addition to the prognosis and the preventive strategies.

Role of acute exacerbations in skeletal muscle impairment in COPD

Introduction: Muscle impairments are prevalent in COPD and have adverse clinical implications in terms of physical performance capacity, disease burden, quality of life and even mortality. During acute exacerbations of COPD (AECOPDs) the respiratory symptoms worsen and this might also apply to the muscle impairments. Areas covered: This report includes a review of both clinical and pre-clinical peer-reviewed literature of the past 20 years found in PubMed providing a comprehensive view on the role of AECOPD in muscle dysfunction in COPD, the putative underlying mechanisms and the treatment perspectives. Expert opinion: The contribution of AECOPD and its recurrent nature to muscle impairment in COPD cannot be ignored and can be attributed to the acutely intensifying and converging disease-related drivers of muscle deterioration, in particular disuse, systemic inflammation and corticosteroid treatment. The search for novel treatment options should focus on the AECOPD-enhanced drivers of muscle dysfunction as well as on the underlying, mainly catabolic, mechanisms. Considering the impact of AECOPD on muscle function, and that of muscle impairment on the recurrence of exacerbations, counteracting muscle deterioration in AECOPD provides an unprecedented therapeutic opportunity.

Pre-operative optimisation for chronic obstructive pulmonary disease: a narrative review

Chronic obstructive pulmonary disease is a condition commonly present in older people undergoing surgery and confers an increased risk of postoperative complications and mortality. Although predominantly a respiratory disease, it frequently has extra-pulmonary manifestations and typically occurs in the context of other long-term conditions. Patients experience a range of symptoms that affect their quality of life, functional ability and clinical outcomes. In this review, we discuss the evidence for techniques to optimise the care of people with chronic obstructive pulmonary disease in the peri-operative period, and address potential new interventions to improve outcomes. The article centres on pulmonary rehabilitation, widely available for the treatment of stable chronic obstructive pulmonary disease, but less often used in a peri-operative setting. Current evidence is largely at high risk of bias, however. Before surgery it is important to ensure that what have been called the 'five fundamentals' of chronic obstructive pulmonary disease treatment are achieved: smoking cessation; pulmonary rehabilitation; vaccination; self-management; and identification and optimisation of co-morbidities. Pharmacological treatment should also be optimised, and some patients may benefit from lung volume reduction surgery. Psychological and behavioural factors are important, but are currently poorly understood in the peri-operative period. Considerations of the risk and benefits of delaying surgery to ensure the recommended measures are delivered depends on patient characteristics and the nature and urgency of the planned intervention.

Nonpharmacologic Therapies in Patients With Exacerbation of Chronic Obstructive Pulmonary Disease: A Systematic Review With Meta-Analysis

OBJECTIVE

To evaluate the effectiveness and adverse events of nonpharmacologic interventions in patients with exacerbation of chronic obstructive pulmonary disease (COPD).

PATIENTS AND METHODS

We searched Embase, MEDLINE, Cochrane databases, Scopus, and clinicaltrials.gov from database inception to January 2, 2019, for randomized controlled trials that enrolled adults with exacerbation of COPD and evaluated the effect of nonpharmacologic interventions on clinical outcomes and/or lung function.

RESULTS

We included 30 randomized controlled trials with 2643 participants. Improvement in 6-minute walking test distance was associated with resistance training (weighted mean difference [WMD], 74.42; 95% CI, 46.85 to 101.99), pulmonary rehabilitation (WMD, 20.02; 95% CI, 12.06 to 28.67), whole body vibration (WMD, 89.42; 95% CI, 45.18 to 133.66), and transcutaneous electrical nerve stimulation (WMD, 64.54; 95% CI, 53.76 to 75.32). Improvement in quality of life was associated with resistance training (WMD, 18.7; 95% CI, 5.06 to 32.34), combined breathing technique and range of motion exercises (WMD, 14.89; 95% CI, 5.30 to 24.50), whole body vibration (WMD, -12.02; 95% CI, -21.41 to -2.63), and intramuscular vitamin D (WMD, -4.67; 95% CI, -6.00 to -3.35 at the longest follow-up). Oxygen titration with a target oxygen saturation range of 88% to 92% was associated with reduced mortality compared with high flow oxygen (odds ratio, 0.36; 95% CI, 0.14 to 0.88). All findings were based on low strength of evidence.

CONCLUSION

In patients hospitalized for exacerbation of COPD, exercise interventions and pulmonary rehabilitation programs may ameliorate functional decline. Oxygen should be titrated with a target oxygen saturation of 88% to 92% in these patients.

TRIAL REGISTRATION

PROSPERO Identifier: CRD42018111609.

Association of Nutritional Support With Clinical Outcomes Among Medical Inpatients Who Are Malnourished or at Nutritional Risk: An Updated Systematic Review and Meta-analysis

IMPORTANCE

Malnutrition affects a considerable proportion of the medical inpatient population. There is uncertainty regarding whether use of nutritional support during hospitalization in these patients positively alters their clinical outcomes.

OBJECTIVE

To assess the association of nutritional support with clinical outcomes in medical inpatients who are malnourished or at nutritional risk.

DATA SOURCES

For this updated systematic review and meta-analysis, a search of the Cochrane Library, MEDLINE, and Embase was conducted from January 1, 2015, to April 30, 2019; the included studies were published between 1982 and 2019.

STUDY SELECTION

A prespecified Cochrane protocol was followed to identify trials comparing oral and enteral nutritional support interventions with usual care and the association of these treatments with clinical outcomes in non-critically ill medical inpatients who were malnourished.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently extracted data and assessed risk of bias; data were pooled using a random-effects model.

MAIN OUTCOMES AND MEASURES

The primary outcome was mortality. The secondary outcomes included nonelective hospital readmissions, length of hospital stay, infections, functional outcome, daily caloric and protein intake, and weight change.

RESULTS

A total of 27 trials (n = 6803 patients) were included, of which 5 (n = 3067 patients) were published between 2015 and 2019. Patients receiving nutritional support compared with patients in the control group had significantly lower rates of mortality (230 of 2758 [8.3%] vs 307 of 2787 [11.0%]; odds ratio [OR], 0.73; 95% CI, 0.56-0.97). A sensitivity analysis suggested a more pronounced reduction in the risk of mortality in recent trials (2015 or later) (OR, 0.47; 95% CI, 0.28-0.79) compared with that in older studies (OR, 0.94; 95% CI, 0.72-1.22), in patients with established malnutrition (OR, 0.52; 95% CI, 0.34-0.80) compared with that in patients at nutritional risk (OR, 0.85; 95% CI, 0.62-1.18), and in trials with high protocol adherence (OR, 0.67; 95% CI, 0.54-0.84) compared with that in trials with low protocol adherence (OR, 0.88; 95% CI, 0.44-1.76). Nutritional support was also associated with a reduction in nonelective hospital readmissions (14.7% vs 18.0%; risk ratio, 0.76; 95% CI, 0.60-0.96), higher energy intake (mean difference, 365 kcal; 95% CI, 272-458 kcal) and protein intake (mean difference, 17.7 g; 95% CI, 12.1-23.3 g), and weight increase (0.73 kg; 95% CI, 0.32-1.13 kg). No significant differences were observed in rates of infections (OR, 0.86; 95% CI, 0.64-1.16), functional outcome (mean difference, 0.32; 95% CI, -0.51 to 1.15), and length of hospital stay (mean difference, -0.24; 95% CI, -0.58 to 0.09).

CONCLUSIONS AND RELEVANCE

This study's findings suggest that despite heterogeneity and varying methodological quality among trials, nutritional support was associated with improved survival and nonelective hospital readmission rates among medical inpatients who were malnourished and should therefore be considered when treating this population.

Nutritional support in chronic obstructive pulmonary disease (COPD): an evidence update

Chronic obstructive pulmonary disease (COPD) primarily affects the lungs but due to the accompanying chronic systematic inflammation and the symptoms associated with the disease there are many extrapulmonary effects which include complex physical and metabolic adaptations. These changes have been associated with reduced exercise capacity, increased nutritional requirements, altered metabolic processes and compromised nutritional intake. As a result, nutritional depletion in COPD is multi-faceted and can involve imbalances of energy (weight loss), protein (sarcopenia), and periods of markedly increased inflammation (pulmonary cachexia) which can increase nutritional losses. As a result, depletion of both fat-mass (FM) and fat-free mass (FFM) can occur. There is good evidence that nutritional support, in the form of oral nutritional supplements (ONS), can overcome energy and protein imbalances resulting in improved nutritional status and functional capacity. However, in order to treat the aetiology of sarcopenia, frailty and cachexia, it is likely that targeted multi-modal interventions are required to address energy and protein imbalance, specific nutrient deficiencies, reduced androgens and targeted exercise training. Furthermore, interventions taking a disease-course approach, are likely to hold the key to effectively managing the common and costly problem of nutritional depletion in COPD.

Deterioration of Limb Muscle Function during Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Important features of both stable and acute exacerbation of chronic obstructive pulmonary disease (COPD) are skeletal muscle weakness and wasting. Limb muscle dysfunction during an exacerbation has been linked to various adverse outcomes, including prolonged hospitalization, readmission, and mortality. The contributing factors leading to muscle dysfunction are similar to those seen in stable COPD: disuse, nutrition/energy balance, hypercapnia, hypoxemia, electrolyte derangements, inflammation, and drugs (i.e., glucocorticoids). These factors may be the trigger for a downstream cascade of local inflammatory changes, pathway process alterations, and structural degradation. Ultimately, the clinical effects can be wide ranging and include reduced limb muscle strength. Current therapies, such as pulmonary/physical rehabilitation, have limited impact because of low participation rates. Recently, novel drugs have been developed in similar disorders, and learnings from these studies can be used as a foundation to facilitate discovery in patients hospitalized with a COPD exacerbation. Nevertheless, investigators should approach this patient population with knowledge of the limitations of each intervention. In this Concise Clinical Review, we provide an overview of acute muscle dysfunction in patients hospitalized with acute exacerbation of COPD and a strategic approach to drug development in this setting.

The feasibility of early pulmonary rehabilitation and activity after COPD exacerbations: external pilot randomised controlled trial, qualitative case study and exploratory economic evaluation

BACKGROUND

Chronic obstructive pulmonary disease (COPD) affects > 3 million people in the UK. Acute exacerbations of COPD (AECOPD) are the second most common reason for emergency hospital admission in the UK. Pulmonary rehabilitation is usual care for stable COPD but there is little evidence for early pulmonary rehabilitation (EPR) following AECOPD, either in hospital or immediately post discharge.

OBJECTIVE

To assess the feasibility of recruiting patients, collecting data and delivering EPR to patients with AECOPD to evaluate EPR compared with usual care.

DESIGN

Parallel-group, pilot 2 × 2 factorial randomised trial with nested qualitative research and an economic analysis.

SETTING

Two acute hospital NHS trusts. Recruitment was carried out from September 2015 to April 2016 and follow-up was completed in July 2016.

PARTICIPANTS

Eligible patients were those aged ≥ 35 years who were admitted with AECOPD, who were non-acidotic and who maintained their blood oxygen saturation level (SpO₂) within a prescribed range. Exclusions included the presence of comorbidities that affected the ability to undertake the interventions.

INTERVENTIONS

(1) Hospital EPR: muscle training delivered at the patient's hospital bed using a cycle ergometer and (2) home EPR: a pulmonary rehabilitation programme delivered in the patient's home. Both interventions were delivered by trained physiotherapists. Participants were allocated on a 1 : 1 : 1 : 1 ratio to (1) hospital EPR (n = 14), (2) home EPR (n = 15), (3) hospital EPR and home EPR (n = 14) and (4) control (n = 15). Outcome assessors were blind to treatment allocation; it was not possible to blind patients.

MAIN OUTCOME MEASURES

Feasibility of recruiting 76 participants in 7 months at two centres; intervention delivery; views on intervention/research acceptability; clinical outcomes including the 6-minute walk distance (6WMD); and costs. Semistructured interviews with participants (n = 27) and research health professionals (n = 11), optimisation assessments and an economic analysis were also undertaken.

RESULTS

Over 7 months 449 patients were screened, of whom most were not eligible for the trial or felt too ill/declined entry. In total, 58 participants (76%) of the target 76 participants were recruited to the trial. The primary clinical outcome (6MWD) was difficult to collect (hospital EPR, n = 5; home EPR, n = 6; hospital EPR and home EPR, n = 5; control, n = 5). Hospital EPR was difficult to deliver over 5 days because of patient discharge/staff availability, with 34.1% of the scheduled sessions delivered compared with 78.3% of the home EPR sessions. Serious adverse events were experienced by 26 participants (45%), none of which was related to the interventions. Interviewed participants generally found both interventions to be acceptable. Home EPR had a higher rate of acceptability, mainly because patients felt too unwell when in hospital to undergo hospital EPR. Physiotherapists generally found the interventions to be acceptable and valued them but found delivery difficult because of staffing issues. The health economic analysis results suggest that there would be value in conducting a larger trial to assess the cost-effectiveness of the hospital EPR and hospital EPR plus home EPR trial arms and collect more information to inform the hospital cost and quality-adjusted life-year parameters, which were shown to be key drivers of the model.

CONCLUSIONS

A full-scale randomised controlled trial using this protocol would not be feasible. Recruitment and delivery of the hospital EPR intervention was difficult. The data obtained can be used to design a full-scale trial of home EPR. Because of the small sample and large confidence intervals, this study should not be used to inform clinical practice.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN18634494.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 11. See the NIHR Journals Library website for further project information.

Frailty trajectories in adult lung transplantation: A cohort study

BACKGROUND

Frailty is common in adults with advanced lung disease and is associated with death before and after lung transplantation. We aimed to determine whether frailty changes from before to after the lung transplant.

METHODS

In a single-center, prospective cohort study among adults undergoing lung transplantation from 2010 to 2017, we assessed frailty by the Short Physical Performance Battery (SPPB; higher scores reflect less frailty) and Fried Frailty Phenotype (FFP; higher scores reflect greater frailty) before and repeatedly up to 36 months after transplant. We tested for changes in frailty scores over time using segmented mixed effects models, adjusting for age, sex, and diagnosis. We quantified the proportion of subjects transitioning between frailty states (frail vs not frail) from before to after the transplant.

RESULTS

In 246 subjects, changes in frailty occurred within the first 6 post-operative months and remained stable thereafter. The overall change in frailty was attributable to improvements among those subjects who were frail before transplant. They experienced a 5.1-point improvement in SPPB (95% confidence interval [CI] 4.6-5.7) and a 1.8-point improvement in FFP (95% CI -2.1 to -1.6) during the early period. Frailty by SPPB and FFP did not change in those who were not frail before transplant. Approximately 84% of survivors who were frail before transplant became not frail after transplant.

CONCLUSIONS

Pre-operative frailty resolves in many patients after lung transplantation. Because a large proportion of frailty may be attributable to advanced lung disease, frailty alone should not be an absolute contraindication to transplantation.

Differences in plasma amino acid levels in patients with and without bacterial infection during the early stage of acute exacerbation of COPD

PURPOSE

No consensus has been reached regarding appropriate nutritional intervention and rehabilitation during early acute exacerbation of COPD (AECOPD). Given the individual differences in symptoms of AECOPD, patients should be classified by their pathology. For example, it is known that there are differences in the inflammatory response between AECOPD with and without bacterial infection. However, there have been few reports on AECOPD from a nutritional perspective. The aim of this study was to investigate amino acid levels in patients with AECOPD.

PATIENTS AND METHODS

Blood was collected from patients who were hospitalized with AECOPD and from patients with COPD that was in a stable state. We divided the patients with AECOPD into those without bacterial infection (group A) and those with bacterial infection (group B). The patients with COPD that was stable served as controls (group C). The plasma levels of 9 essential amino acids, 13 nonessential amino acids, and total amino acids were compared between the three groups.

RESULTS

In the early stages of AECOPD, differences in plasma levels of only three amino acids (glycine, phenylalanine, and arginine) were observed between groups C and A. Differences in total amino acids and 13 amino acids were observed between groups C and B. Group B had lower levels of total amino acids and of seven amino acids (asparagine, citrulline, glutamine, histidine, methionine, serine, and threonine) compared with the other study groups.

CONCLUSION

The findings of this study show that amino acid levels in plasma differ in patients with AECOPD depending on whether or not bacterial infection is present. Our results suggest that specific amino acids (ie, asparagine, citrulline, glutamine, histidine, serine, and threonine) have potential utility as diagnostic markers to distinguish between bacterial and nonbacterial AECOPD.

Change in skeletal muscle associated with unplanned hospital admissions in adult patients: A systematic review and meta-analysis

OBJECTIVES

The primary objective of the review was to describe change that occurs in skeletal muscle during periods of unplanned hospitalisation in adult patients. The secondary objective was to examine the relationship between both physical activity and inflammation with the change in skeletal muscle. A further objective was to investigate the effect of interventions on change in skeletal muscle during periods of unplanned hospitalisation.

DESIGN

A systematic review and meta-analyses. Embase, MEDLINE, CINAHL, AMED, PEDro and the Cochrane Library were searched for studies that included any measures of skeletal muscle (excluding pulmonary function) at two time points during unplanned hospitalisation. Studies that were set in critical care, or included patients with acute or progressive neurological illness, were excluded.

RESULTS

Our search returned 27,809 unique articles, of which 35 met the inclusion criteria. Meta-analyses of change between baseline and follow-up in random effects models suggested that grip strength had an average increase: standardised mean difference (SMD) = 0.10 (95% CI: 0.03; 0.16); knee extension strength had an average reduction: SMD = -0.24 (95% CI: -0.33; -0.14); and mid-arm muscle circumference had an average reduction: SMD = -0.17 (95% CI: -0.22; -0.11). Inflammation appeared to be associated with greater loss of muscle strength. There was inconclusive evidence that the level of physical activity affects change in skeletal muscle. In regard to the effect of interventions, only exercise interventions were consistently associated with improved skeletal muscle outcomes.

CONCLUSIONS

Adult patients who undergo an unplanned hospital admission may experience a small reduction in knee extension strength and mid-arm muscle mass. Prospective research is needed to clarify the contribution of confounding factors underlying the observations made in this review, with particular attention to levels of physical activity, and possible contributions from environmental factors and processes of hospital care.

Caloric intake and the fat-to-carbohydrate ratio in hypercapnic acute respiratory failure: Post-hoc analysis of the PermiT trial

BACKGROUND

The effect of moderate caloric enteral intake in critically ill patients with hypercapnic acute respiratory failure (HCARF) is unclear. We studied the impact of permissive underfeeding (PUF) compared with standard feeding (SF) on various HCARF outcomes.

MATERIALS AND METHODS

The PermiT trial randomized 894 patients to either PUF (40-60% caloric requirement) or SF (70-100% requirement) with similar protein intake and found no difference in mortality, mechanical ventilation (MV) duration and ventilator-free days. In this post-hoc study, we restricted analysis to mechanically-ventilated patients with HCARF (PaCO₂ >45 mmHg on the first two study days) and assessed the impact of trial interventions and fat-to-carbohydrate ratio on outcomes.

RESULTS

One-hundred-twenty patients had HCARF (59 PUF and 61 SF, age 53.7 ± 17.8 years, body mass index 31.1 ± 11.2 kg/m², Acute Physiology and Chronic Health Evaluation II score 21.7 ± 7.1 and day-1 PaCO₂ 61 ± 16 mmHg). Caloric intake was 815 ± 270 kcal/day in PUF group and 1289 ± 407 kcal/day in SF group. The two groups had similar PaCO₂ levels during ICU stay. The 90-day mortality (33.9% versus 35.6%, p = 0.85), MV duration (10.7 ± 6.8 versus 11.1 ± 8.1 days, p = 0.56) and ventilator-free days (52.9 ± 38.6 versus 51.2 ± 38.0 days, p = 0.80) were also similar in PUF and SF groups, respectively. Ventilator-free days and 90-day mortality were similar when the fat-to-carbohydrate ratio was < or ≥ the median value (0.73) in all patients and in PUF and SF groups.

CONCLUSIONS

In patients with HCARF, SF and PUF were associated with similar PaCO₂, MV duration, ventilator-free days and mortality. Fat-to-carbohydrate ratio was not associated with mortality or ventilator-free days.

TRIAL REGISTRATION

ISRCTN Registry: ISRCTN68144998.

Relevance of nutritional support and early rehabilitation in hospitalized patients with COPD

Exacerbation of COPD is associated with a worsening of lung function and symptoms, and a serious loss in functional status and health related quality of life. It also represents the major cause for emergency hospitalization in COPD patients which places the patient at risk for developing further muscle weakness. Actually, loss of muscle function developed fast and continued to decrease over time during hospitalization and may be further compromised when disease deterioration would require the use of ventilator support. Exacerbations have long term consequences on physical performance, physical activity and health-related quality of life as recovery of skeletal muscle function is slow and incomplete and may even be compromised in case of re-exacerbation. Factors such as bed rest, reduced physical activity, hypoxia, inflammation, drug treatment and negative protein balance due to insufficient dietary intake and increased resting energy expenditure are all potential contributors to skeletal muscle weakness during exacerbation. Because low levels of physical activity and poor physical performance are predictor of hospital re-admission and are associated with lower survival in these patients, interventions to prevent the additional loss of muscle function during exacerbation or to hasten functional recovery have been recently explored. This review focuses on the knowledge regarding the potential benefit of early rehabilitation and nutritional supplementation as modifiable factors susceptible to ameliorate muscle weakness during exacerbation in hospitalized COPD patients.

Nutrition support in hospitalised adults at nutritional risk

BACKGROUND

The prevalence of disease-related malnutrition in Western European hospitals is estimated to be about 30%. There is no consensus whether poor nutritional status causes poorer clinical outcome or if it is merely associated with it. The intention with all forms of nutrition support is to increase uptake of essential nutrients and improve clinical outcome. Previous reviews have shown conflicting results with regard to the effects of nutrition support.

OBJECTIVES

To assess the benefits and harms of nutrition support versus no intervention, treatment as usual, or placebo in hospitalised adults at nutritional risk.

SEARCH METHODS

We searched Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE (Ovid SP), Embase (Ovid SP), LILACS (BIREME), and Science Citation Index Expanded (Web of Science). We also searched the World Health Organization International Clinical Trials Registry Platform (www.who.int/ictrp); ClinicalTrials.gov; Turning Research Into Practice (TRIP); Google Scholar; and BIOSIS, as well as relevant bibliographies of review articles and personal files. All searches are current to February 2016.

SELECTION CRITERIA

We include randomised clinical trials, irrespective of publication type, publication date, and language, comparing nutrition support versus control in hospitalised adults at nutritional risk. We exclude trials assessing non-standard nutrition support.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane and the Cochrane Hepato-Biliary Group. We used trial domains to assess the risks of systematic error (bias). We conducted Trial Sequential Analyses to control for the risks of random errors. We considered a P value of 0.025 or less as statistically significant. We used GRADE methodology. Our primary outcomes were all-cause mortality, serious adverse events, and health-related quality of life.

MAIN RESULTS

We included 244 randomised clinical trials with 28,619 participants that met our inclusion criteria. We considered all trials to be at high risk of bias. Two trials accounted for one-third of all included participants. The included participants were heterogenous with regard to disease (20 different medical specialties). The experimental interventions were parenteral nutrition (86 trials); enteral nutrition (tube-feeding) (80 trials); oral nutrition support (55 trials); mixed experimental intervention (12 trials); general nutrition support (9 trials); and fortified food (2 trials). The control interventions were treatment as usual (122 trials); no intervention (107 trials); and placebo (15 trials). In 204/244 trials, the intervention lasted three days or more.We found no evidence of a difference between nutrition support and control for short-term mortality (end of intervention). The absolute risk was 8.3% across the control groups compared with 7.8% (7.1% to 8.5%) in the intervention groups, based on the risk ratio (RR) of 0.94 (95% confidence interval (CI) 0.86 to 1.03, P = 0.16, 21,758 participants, 114 trials, low quality of evidence). We found no evidence of a difference between nutrition support and control for long-term mortality (maximum follow-up). The absolute risk was 13.2% in the control group compared with 12.2% (11.6% to 13%) following nutritional interventions based on a RR of 0.93 (95% CI 0.88 to 0.99, P = 0.03, 23,170 participants, 127 trials, low quality of evidence). Trial Sequential Analysis showed we only had enough information to assess a risk ratio reduction of approximately 10% or more. A risk ratio reduction of 10% or more could be rejected.We found no evidence of a difference between nutrition support and control for short-term serious adverse events. The absolute risk was 9.9% in the control groups versus 9.2% (8.5% to 10%), with nutrition based on the RR of 0.93 (95% CI 0.86 to 1.01, P = 0.07, 22,087 participants, 123 trials, low quality of evidence). At long-term follow-up, the reduction in the risk of serious adverse events was 1.5%, from 15.2% in control groups to 13.8% (12.9% to 14.7%) following nutritional support (RR 0.91, 95% CI 0.85 to 0.97, P = 0.004, 23,413 participants, 137 trials, low quality of evidence). However, the Trial Sequential Analysis showed we only had enough information to assess a risk ratio reduction of approximately 10% or more. A risk ratio reduction of 10% or more could be rejected.Trial Sequential Analysis of enteral nutrition alone showed that enteral nutrition might reduce serious adverse events at maximum follow-up in people with different diseases. We could find no beneficial effect of oral nutrition support or parenteral nutrition support on all-cause mortality and serious adverse events in any subgroup.Only 16 trials assessed health-related quality of life. We performed a meta-analysis of two trials reporting EuroQoL utility score at long-term follow-up and found very low quality of evidence for effects of nutritional support on quality of life (mean difference (MD) -0.01, 95% CI -0.03 to 0.01; 3961 participants, two trials). Trial Sequential Analyses showed that we did not have enough information to confirm or reject clinically relevant intervention effects on quality of life.Nutrition support may increase weight at short-term follow-up (MD 1.32 kg, 95% CI 0.65 to 2.00, 5445 participants, 68 trials, very low quality of evidence).

AUTHORS' CONCLUSIONS

There is low-quality evidence for the effects of nutrition support on mortality and serious adverse events. Based on the results of our review, it does not appear to lead to a risk ratio reduction of approximately 10% or more in either all-cause mortality or serious adverse events at short-term and long-term follow-up.There is very low-quality evidence for an increase in weight with nutrition support at the end of treatment in hospitalised adults determined to be at nutritional risk. The effects of nutrition support on all remaining outcomes are unclear.Despite the clinically heterogenous population and the high risk of bias of all included trials, our analyses showed limited signs of statistical heterogeneity. Further trials may be warranted, assessing enteral nutrition (tube-feeding) for different patient groups. Future trials ought to be conducted with low risks of systematic errors and low risks of random errors, and they also ought to assess health-related quality of life.

Supportive interventions for enhancing dietary intake in malnourished or nutritionally at-risk adults

BACKGROUND

Supportive interventions such as serving meals in a dining room environment or the use of assistants to feed patients are frequently recommended for the management of nutritionally vulnerable groups. Such interventions are included in many policy and guideline documents and have implications for staff time but may incur additional costs, yet there appears to be a lack of evidence for their efficacy.

OBJECTIVES

To assess the effects of supportive interventions for enhancing dietary intake in malnourished or nutritionally at-risk adults.

SEARCH METHODS

We identified publications from comprehensive searches of the Cochrane Library, MEDLINE, Embase, AMED, British Nursing Index, CINAHL, SCOPUS, ISI Web of Science databases, scrutiny of the reference lists of included trials and related systematic reviews and handsearching the abstracts of relevant meetings. The date of the last search for all databases was 31 March 2013. Additional searches of CENTRAL, MEDLINE, ClinicalTrials.gov and WHO ICTRP were undertaken to September 2016. The date of the last search for these databases was 14 September 2016.

SELECTION CRITERIA

Randomised controlled trials of supportive interventions given with the aim of enhancing dietary intake in nutritionally vulnerable adults compared with usual care.

DATA COLLECTION AND ANALYSIS

Three review authors and for the final search, the editor, selected trials from titles and abstracts and independently assessed eligibility of selected trials. Two review authors independently extracted data and assessed risk of bias, as well as evaluating overall quality of the evidence utilising the GRADE instrument, and then agreed as they entered data into the review. The likelihood of clinical heterogeneity amongst trials was judged to be high as trials were in populations with widely different clinical backgrounds, conducted in different healthcare settings and despite some grouping of similar interventions, involved interventions that varied considerably. We were only able, therefore, to conduct meta-analyses for the outcome measures, 'all-cause mortality', 'hospitalisation' and 'nutritional status (weight change)'.

MAIN RESULTS

Forty-one trials (10,681 participants) met the inclusion criteria. Trials were grouped according to similar interventions (changes to organisation of nutritional care (N = 13; 3456 participants), changes to the feeding environment (N = 5; 351 participants), modification of meal profile or pattern (N = 12; 649 participants), additional supplementation of meals (N = 10; 6022 participants) and home meal delivery systems (N = 1; 203 participants). Follow-up ranged from 'duration of hospital stay' to 12 months.The overall quality of evidence was moderate to very low, with the majority of trials judged to be at an unclear risk of bias in several risk of bias domains. The risk ratio (RR) for all-cause mortality was 0.78 (95% confidence interval (CI) 0.66 to 0.92); P = 0.004; 12 trials; 6683 participants; moderate-quality evidence. This translates into 26 (95% CI 9 to 41) fewer cases of death per 1000 participants in favour of supportive interventions. The RR for number of participants with any medical complication ranged from 1.42 in favour of control compared with 0.59 in favour of supportive interventions (very low-quality evidence). Only five trials (4451 participants) investigated health-related quality of life showing no substantial differences between intervention and comparator groups. Information on patient satisfaction was unreliable. The effects of supportive interventions versus comparators on hospitalisation showed a mean difference (MD) of -0.5 days (95% CI -2.6 to 1.6); P = 0.65; 5 trials; 667 participants; very low-quality evidence. Only three of 41 included trials (4108 participants; very low-quality evidence) reported on adverse events, describing intolerance to the supplement (diarrhoea, vomiting; 5/34 participants) and discontinuation of oral nutritional supplements because of refusal or dislike of taste (567/2017 participants). Meta-analysis across 17 trials with adequate data on weight change revealed an overall improvement in weight in favour of supportive interventions versus control: MD 0.6 kg (95% CI 0.21 to 1.02); 2024 participants; moderate-quality evidence. A total of 27 trials investigated nutritional intake with a majority of trials not finding marked differences in energy intake between intervention and comparator groups. Only three trials (1152 participants) reported some data on economic costs but did not use accepted health economic methods (very low-quality evidence).

AUTHORS' CONCLUSIONS

There is evidence of moderate to very low quality to suggest that supportive interventions to improve nutritional care results in minimal weight gain. Most of the evidence for the lower risk of all-cause mortality for supportive interventions comes from hospital-based trials and more research is needed to confirm this effect. There is very low-quality evidence regarding adverse effects; therefore whilst some of these interventions are advocated at a national level clinicians should recognise the lack of clear evidence to support their role. This review highlights the importance of assessing patient-important outcomes in future research.

The effect of protein intake and resistance training on muscle mass in acutely ill old medical patients - A randomized controlled trial

BACKGROUND & AIM

Stress metabolism is associated with accelerated loss of muscle that has large consequences for the old medical patient. The aim of this study was to investigate if an intervention combining protein and resistance training was more effective in counteracting loss of muscle than standard care. Secondary outcomes were changes in muscle strength, functional ability and body weight.

METHODS

29 acutely admitted old (>65 years) patients were randomly assigned to the intervention (n = 14) or to standard care (n = 15). The Intervention Group received 1.7 g protein/kg/day during admission and a daily protein supplement (18.8 g protein) and resistance training 3 times per week the 12 weeks following discharge. Muscle mass was assessed by Dual-energy X-ray Absorptiometry. Muscle strength was assessed by Hand Grip Strength and Chair Stand Test. Functional ability was assessed by the de Morton Mobility Index, the Functional Recovery Score and the New Mobility Score. Changes in outcomes from time of admission to three-months after discharge were analysed by linear regression analysis.

RESULTS

The intention-to-treat analysis showed no significant effect of the intervention on lean mass (unadjusted: β-coefficient = -1.28 P = 0.32, adjusted for gender: β-coefficient = -0.02 P = 0.99, adjusted for baseline lean mass: β-coefficient = -0.31 P = 0.80). The de Morton Mobility Index significantly increased in the Control Group (β-coefficient = -11.43 CI: 0.72-22.13, P = 0.04). No other differences were found.

CONCLUSION

No significant effect on muscle mass was observed in this group of acutely ill old medical patients. High compliance was achieved with the dietary intervention, but resistance training was challenging. Clinical trials identifier NCT02077491.

Nutritional assessment and therapy in COPD: a European Respiratory Society statement

Nutrition and metabolism have been the topic of extensive scientific research in chronic obstructive pulmonary disease (COPD) but clinical awareness of the impact dietary habits, nutritional status and nutritional interventions may have on COPD incidence, progression and outcome is limited. A multidisciplinary Task Force was created by the European Respiratory Society to deliver a summary of the evidence and description of current practice in nutritional assessment and therapy in COPD, and to provide directions for future research. Task Force members conducted focused reviews of the literature on relevant topics, advised by a methodologist. It is well established that nutritional status, and in particular abnormal body composition, is an important independent determinant of COPD outcome. The Task Force identified different metabolic phenotypes of COPD as a basis for nutritional risk profile assessment that is useful in clinical trial design and patient counselling. Nutritional intervention is probably effective in undernourished patients and probably most when combined with an exercise programme. Providing evidence of cost-effectiveness of nutritional intervention is required to support reimbursement and thus increase access to nutritional intervention. Overall, the evidence indicates that a well-balanced diet is beneficial to all COPD patients, not only for its potential pulmonary benefits, but also for its proven benefits in metabolic and cardiovascular risk.

An official American Thoracic Society/European Respiratory Society statement: update on limb muscle dysfunction in chronic obstructive pulmonary disease

BACKGROUND

Limb muscle dysfunction is prevalent in chronic obstructive pulmonary disease (COPD) and it has important clinical implications, such as reduced exercise tolerance, quality of life, and even survival. Since the previous American Thoracic Society/European Respiratory Society (ATS/ERS) statement on limb muscle dysfunction, important progress has been made on the characterization of this problem and on our understanding of its pathophysiology and clinical implications.

PURPOSE

The purpose of this document is to update the 1999 ATS/ERS statement on limb muscle dysfunction in COPD.

METHODS

An interdisciplinary committee of experts from the ATS and ERS Pulmonary Rehabilitation and Clinical Problems assemblies determined that the scope of this document should be limited to limb muscles. Committee members conducted focused reviews of the literature on several topics. A librarian also performed a literature search. An ATS methodologist provided advice to the committee, ensuring that the methodological approach was consistent with ATS standards.

RESULTS

We identified important advances in our understanding of the extent and nature of the structural alterations in limb muscles in patients with COPD. Since the last update, landmark studies were published on the mechanisms of development of limb muscle dysfunction in COPD and on the treatment of this condition. We now have a better understanding of the clinical implications of limb muscle dysfunction. Although exercise training is the most potent intervention to address this condition, other therapies, such as neuromuscular electrical stimulation, are emerging. Assessment of limb muscle function can identify patients who are at increased risk of poor clinical outcomes, such as exercise intolerance and premature mortality.

CONCLUSIONS

Limb muscle dysfunction is a key systemic consequence of COPD. However, there are still important gaps in our knowledge about the mechanisms of development of this problem. Strategies for early detection and specific treatments for this condition are also needed.

Changes in body composition after lung transplantation in children

BACKGROUND

The evaluation of nutritional status, including body composition measurements, in pediatric patients before and after lung transplant (LTx) can aid in adapting nutrition support and physical rehabilitation programs to meet individual patient needs. The purpose of this retrospective study was to determine the changes in weight, lean body mass (LBM), and body fat (BF) before and after LTx and their association with lung function in pediatric patients.

METHODS

Included were 41 LTx patients, aged 3 months to 20.7 years, who had at least 2 body composition measurements determined by dual-energy X-ray absorptiometry (GE Lunar Prodigy, Waukesha, WI) in the first 2 years after LTx were measured pre-LTX and at 12 or 24 months post-LTX, for weight, LBM, and BF.

RESULTS

Pre-LTx, 29% of patients had moderate and 12% had severe chronic malnutrition (growth stunting). This compares with 21% of patients being moderately LBM-depleted and 23% being BF-depleted. The weight change at 12 and 24 months was +9.3% (interquartile range, 5.6%-23%) and +4.7% (0.9%-11.6%), respectively; whereas the LBM change at 12 and 24 months was +15.2% (6.8%-17.1%) and +4.2% (-0.6% to 7.7%), respectively. LBM percentiles correlated with pulmonary function tests ( % predicted forced vital capacity [ρ = 0.36, p = 0.001] and forced expiratory volume in 1 second [ρ = 0.265, p = 0.015).

CONCLUSIONS

Maximum weight and LBM gain occur at 12 months after LTx, with smaller gains noted at 24 months. Clinicians must look beyond height and weight and evaluate LBM and fat mass in pediatric patients after LTx.

Mechanisms of striated muscle dysfunction during acute exacerbations of COPD

During acute exacerbations of chronic obstructive pulmonary disease (COPD), limb and respiratory muscle dysfunction develops rapidly and functional recovery is partial and slow. The mechanisms leading to this muscle dysfunction are not yet fully established. However, recent evidence has shown that several pathways involved in muscle catabolism, apoptosis, and oxidative stress are activated in the vastus lateralis muscle of patients during acute exacerbations of COPD, while those implicated in mitochondrial function are downregulated. These pathways may be targeted in different ways by factors related to exacerbations. These factors include enhanced systemic inflammation, oxidative stress, impaired energy balance, hypoxia, hypercapnia and acidosis, corticosteroid treatment, and physical inactivity. Data on the respiratory muscles are limited, but these muscles are undoubtedly overloaded during exacerbations. While they are also subjected to the same systemic elements as the limb muscles (except for inactivity), they also face a specific mechanical disadvantage caused by changes in lung volume during exacerbation. The latter will affect the ability to generate force by the foreshortening of the muscle (especially for the diaphragm), but also by altering rib orientation and motion (especially for the parasternal intercostals and the external intercostals). Because acute exacerbations of COPD are associated with an increase in both prevalence and severity of generalized muscle dysfunction, and both remain present even during recovery, early interventions to minimize muscle dysfunction during exacerbation are warranted. Although rehabilitation may be promising, other therapeutic strategies such as counterbalancing the adverse effects of exacerbations on skeletal muscle pathways may also be used.

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.

[Prevention of COPD exacerbation: a fundamental challenge]

INTRODUCTION

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are a cause of suffering for patients and a burden for healthcare systems and society. Their prevention represents individual and collective challenge. The present article is based on the work of a group of experts who met on 5th and 6th May 2011 and seeks to highlight the importance of AECOPD.

STATE OF THE ART

In the absence of easily quantifiable criteria, the definition of AECOPD varies in the literature, making identification difficult and affecting interpretation of study results. Exacerbations increase mortality and risk of cardiovascular disease. They also increase the risk of developing further exacerbations, accelerate the decline in lung function and contribute to reduction in muscle mass. By limiting physical activity and affecting mental state (anxiety, depression), AECOPD are disabling and impair quality of life. They increase work absenteeism and are responsible for about 60% of the global cost of COPD.

PERSPECTIVES

Earlier identification with simple criteria, possibly associated to patient phenotyping, could be helpful in preventing hospitalization.

CONCLUSIONS

Given their immediate and delayed impact, AECOPD should not be trivialized or neglected. Their prevention is a fundamental issue.

Nutritional support in chronic obstructive pulmonary disease: a systematic review and meta-analysis

BACKGROUND

The efficacy of nutritional support in the management of malnutrition in chronic obstructive pulmonary disease (COPD) is controversial. Previous meta-analyses, based on only cross-sectional analysis at the end of intervention trials, found no evidence of improved outcomes.

OBJECTIVE

The objective was to conduct a meta-analysis of randomized controlled trials (RCTs) to clarify the efficacy of nutritional support in improving intake, anthropometric measures, and grip strength in stable COPD.

DESIGN

Literature databases were searched to identify RCTs comparing nutritional support with controls in stable COPD.

RESULTS

Thirteen RCTs (n = 439) of nutritional support [dietary advice (1 RCT), oral nutritional supplements (ONS; 11 RCTs), and enteral tube feeding (1 RCT)] with a control comparison were identified. An analysis of the changes induced by nutritional support and those obtained only at the end of the intervention showed significantly greater increases in mean total protein and energy intakes with nutritional support of 14.8 g and 236 kcal daily. Meta-analyses also showed greater mean (±SE) improvements in favor of nutritional support for body weight (1.94 ± 0.26 kg, P < 0.001; 11 studies, n = 308) and grip strength (5.3%, P < 0.050; 4 studies, n = 156), which was not shown by ANOVA at the end of the intervention, largely because of bias associated with baseline imbalance between groups.

CONCLUSION

This systematic review and meta-analysis showed that nutritional support, mainly in the form of ONS, improves total intake, anthropometric measures, and grip strength in COPD. These results contrast with the results of previous analyses that were based on only cross-sectional measures at the end of intervention trials.

Respiratory diseases and muscle dysfunction

Many respiratory diseases lead to impaired function of skeletal muscles, influencing quality of life and patient survival. Dysfunction of both respiratory and limb muscles in chronic obstructive pulmonary disease has been studied in depth, and seems to be caused by the complex interaction of general (inflammation, impaired gas exchange, malnutrition, comorbidity, drugs) and local factors (changes in respiratory mechanics and muscle activity, and molecular events). Some of these factors are also present in cystic fibrosis and asthma. In obstructive sleep apnea syndrome, repeated exposure to hypoxia and the absence of reparative rest are believed to be the main causes of muscle dysfunction. Deconditioning appears to be crucial for the functional impairment observed in scoliosis. Finally, cachexia seems to be the main mechanism of muscle dysfunction in advanced lung cancer. A multidimensional therapeutic approach is recommended, including pulmonary rehabilitation, an adequate level of physical activity, ventilatory support and nutritional interventions.

Systematic review and meta-analysis of the effects of high protein oral nutritional supplements

Disease-related malnutrition is common, detrimentally affecting the patient and healthcare economy. Although use of high protein oral nutritional supplements (ONS) has been recommended to counteract the catabolic effects of disease and to facilitate recovery from illness, there is a lack of systematically obtained evidence to support these recommendations. This systematic review involving 36 randomised controlled trials (RCT) (n=3790) (mean age 74 years; 83% of trials in patients >65 years) and a series of meta-analyses of high protein ONS (>20% energy from protein) demonstrated a range of effects across settings and patient groups in favour of the high protein ONS group. These included reduced complications (odds ratio (OR) 0.68 (95%CI 0.55-0.83), p<0.001, 10 RCT, n=1830); reduced readmissions to hospital (OR 0.59 (95%CI 0.41-0.84), p=0.004, 2 RCT, n=546); improved grip strength (1.76 kg (95%CI 0.36-3.17), p<0.014, 4 RCT, n=219); increased intake of protein (p<0.001) and energy (p<0.001) with little reduction in normal food intake and improvements in weight (p<0.001). There was inadequate information to compare standard ONS (<20% energy from protein) with high protein ONS (>20% energy from protein). The systematic review and meta-analysis provides evidence that high protein supplements produce clinical benefits, with economic implications.

Dietary advice with or without oral nutritional supplements for disease-related malnutrition in adults

BACKGROUND

Disease-related malnutrition has been reported in 10% to 55% of people in hospital and the community. Dietary advice encouraging the use of energy- and nutrient-rich foods rather than oral nutritional supplements has been suggested as the initial approach for managing disease-related malnutrition.

OBJECTIVES

To examine evidence that dietary advice in adults with disease-related malnutrition improves survival, weight and anthropometry; to estimate the size of any additional effect of nutritional supplements combined with dietary advice and to compare the effects of dietary advice with oral nutritional supplements.

SEARCH STRATEGY

Relevant publications were identified from comprehensive electronic database searches and handsearching.Last search: 14 February 2010.

SELECTION CRITERIA

Randomised controlled trials of dietary advice with or without oral nutritional supplements in people with disease-related malnutrition in any health-care setting compared with no advice, oral nutritional supplements or dietary advice given alone.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility, risk of bias and extracted data.

MAIN RESULTS

Forty-five studies (3186 participants) met the inclusion criteria; (dietary advice compared with: no advice (1053 participants); with oral nutritional supplements (332 participants); with dietary advice and oral nutritional supplements (731 participants); and dietary advice plus oral nutritional supplements compared with no additional intervention (1070 participants). Follow-up ranged from 18 days to 24 months. No comparison showed a significant difference between groups for mortality or morbidity. There was a significant change in weight found between groups when comparing dietary advice to no advice for interventions lasting greater than 12 months, mean difference 3.75 kg (95% confidence interval 0.97 to 6.53), and when all studies were combined, mean difference 1.47 kg (95% confidence interval 0.32 to 2.61) although there was significant heterogeneity in the combined analysis (I(2) = 90%). Similar improvements in weight were found for the comparison of dietary advice with nutritional supplements if required versus no advice, mean difference 2.20 kg (95% confidence interval 1.16 to 3.25). Dietary advice compared with no advice was also associated with significantly improved mid-arm muscle circumference when all studies were combined, but with moderate heterogeneity, mean difference 0.81 mm (95% confidence interval 0.31 to 1.31). Dietary advice given with nutritional supplements compared with dietary advice alone resulted in improvements in: mid-arm muscle circumference, mean difference -0.89 mm (95% confidence interval -1.35 to -0.43); triceps skinfold thickness, mean difference -1.22 mm (95% confidence interval -2.34 to -0.09); and grip strength, mean difference -1.67 kg (95% confidence interval -2.96 to -0.37), although the effects on triceps skinfold thickness and grip strength were heterogeneous. Dietary advice with supplements if required resulted in a significant increase in triceps skinfold thickness compared with no advice, mean difference 0.40 mm (95% confidence interval 0.10 to 0.70), although these results are from a single trial with only 29 participants.

AUTHORS' CONCLUSIONS

Evidence of variable quality suggests that dietary advice with or without oral nutritional supplements may improve weight, body composition and grip strength. We found no evidence of benefit of dietary advice or oral nutritional supplements given alone or in combination on survival. Studies addressing the impact of nutritional interventions on nutritional, functional and patient-centred outcomes are needed.

The Energy Intake That is Needed for Weight Gain in COPD Candidates for Lung Transplantation

Many patients with chronic obstructive pulmonary disease (COPD) have increased resting energy expenditure (REE) and may have an increased need for energy during activity. However, in terms of total energy balance, the influence of differences in REE may be compensated for by differences in daily energy expenditure. Energy needs may therefore be difficult to predict by measuring REE. The aim of this study was to predict the energy intake necessary for weight gain following dietary counselling. We studied 42 COPD patients (n = 27 underweight, n = 15 normal-weight) who were being considered for lung transplantation and had completed an intervention lasting a mean of 22 weeks. In the underweight patients, the dietary intervention consisted of dietary counselling for weight gain, while, in the normal-weight patients it focused on weight maintenance. It has been shown that a weight gain of over 2 kg in patients with COPD improves the prognosis and this was obtained in 52% of our patients. The mean (SD) increase in energy intake in the responders was 3448 (1310) kJ, while it was 635 (2454) kJ, p < 0.01 in the non-responders. Patients who used or had free access to nutritional supplements did not show greater success than patients who only used ordinary foods. Based on the relationship between the dependent variable (kg weight change) and the independent variable (energy intake), we can use linear regression to predict that an energy intake of 180% of REE predicted or 186 kJ/kg (44 kcal/kg) is necessary to obtain a weight gain of 2 kg.

Protein and energy supplementation in elderly people at risk from malnutrition

BACKGROUND

Evidence for the effectiveness of nutritional supplements containing protein and energy, often prescribed for older people, is limited. Malnutrition is more common in this age group and deterioration of nutritional status can occur during illness. It is important to establish whether supplementing the diet is an effective way of improving outcomes for older people at risk from malnutrition.

OBJECTIVES

This review examined trials for improvement in nutritional status and clinical outcomes when extra protein and energy were provided, usually as commercial 'sip-feeds'.

SEARCH STRATEGY

We searched The Cochrane Library, MEDLINE, EMBASE, Healthstar, CINAHL, BIOSIS, CAB abstracts. We also hand searched nutrition journals and reference lists and contacted 'sip-feed' manufacturers.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of oral protein and energy supplementation in older people, with the exception of groups recovering from cancer treatment or in critical care.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trials prior to inclusion and independently extracted data and assessed trial quality. Authors of trials were contacted for further information as necessary.

MAIN RESULTS

Sixty-two trials with 10,187 randomised participants have been included in the review. Maximum duration of intervention was 18 months. Most included trials had poor study quality. The pooled weighted mean difference (WMD) for percentage weight change showed a benefit of supplementation of 2.2% (95% confidence interval (CI) 1.8 to 2.5) from 42 trials. There was no significant reduction in mortality in the supplemented compared with control groups (relative risk (RR) 0.92, CI 0.81 to 1.04) from 42 trials. Mortality results were statistically significant when limited to trials in which participants (N = 2461) were defined as undernourished (RR 0.79, 95% CI 0.64 to 0.97).The risk of complications was reduced in 24 trials (RR 0.86, 95% CI 0.75 to 0.99). Few trials were able to suggest any functional benefit from supplementation. The WMD for length of stay from 12 trials also showed no statistically significant effect (-0.8 days, 95% CI -2.8 to 1.3). Adverse effects included nausea or diarrhoea.

AUTHORS' CONCLUSIONS

Supplementation produces a small but consistent weight gain in older people. Mortality may be reduced in older people who are undernourished. There may also be a beneficial effect on complications which needs to be confirmed. However, this updated review found no evidence of improvement in functional benefit or reduction in length of hospital stay with supplements. Additional data from large-scale multi-centre trials are still required.

Dietary advice for illness-related malnutrition in adults

BACKGROUND

Illness-related malnutrition has been reported in 10% to 55% of ill people in hospital and the community in areas of food sufficiency. Dietary advice encouraging the use of energy- and nutrient-rich foods rather than oral nutritional supplements has been suggested for managing illness-related malnutrition.

OBJECTIVES

To examine evidence that dietary advice to improve nutritional intake in adults with illness-related malnutrition improves survival, weight and anthropometry; to estimate the size of any additional effect of nutritional supplements given in combination with dietary advice.

SEARCH STRATEGY

Relevant publications were identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Additional studies were sought by contacting dietitians, clinicians and the manufacturers of nutritional supplements. Last search: September 2007

SELECTION CRITERIA

Randomised controlled trials of dietary advice in people with illness-related malnutrition compared with:(1) no advice;(2) oral nutritional supplements; and(3) dietary advice plus oral nutritional supplements.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility, methodological quality and extracted data.

MAIN RESULTS

Thirty-six studies (37 comparisons) met the inclusion criteria with 2714 randomised participants. Twelve trials (comparing dietary advice plus supplements if required with no advice) identified during searching are included as a separate comparison. Follow up ranged from 18 days to 24 months. No comparison showed a significant difference in mortality. There are several significant results for change in weight and other nutritional indices favouring nutritional intervention, but the precise contributions of the different strategies have yet to be determined. It is uncertain whether nutritional supplements and dietary advice produce the same effects. There was insufficient evidence to draw conclusions about clinical outcomes and cost. Few data were available for other outcomes.

AUTHORS' CONCLUSIONS

This review highlights the lack of evidence for the provision of dietary advice in managing illness-related malnutrition. Dietary advice plus nutritional supplements may be more effective than dietary advice alone or no advice in enhancing short-term weight gain, but whether this is sustainable, or whether survival and morbidity are improved remains uncertain. A large adequately-powered randomised controlled trial is needed comparing the efficacy of different therapies to increase dietary intake in people with illness-related malnutrition and examining the impact of this on clinical function and survival.

A prospective study of decline in fat free mass and skeletal muscle strength in chronic obstructive pulmonary disease

BACKGROUND

Skeletal muscle depletion is an important complication of chronic obstructive pulmonary disease (COPD) but little prospective data exists about the rate at which it occurs and the factors that promote its development. We therefore prospectively investigated the impact of disease severity, exacerbation frequency and treatment with corticosteroids on change in body composition and maximum isometric quadriceps strength (QMVC) over one year.

METHODS

64 patients with stable COPD (FEV1 mean (SD) 35.8(18.4) %predicted) were recruited from clinic and studied on two occasions one year apart. Fat free mass was determined using bioelectrical impedance analysis and a disease specific regression equation.

RESULTS

QMVC fell from 34.8(1.5) kg to 33.3(1.5) kg (p = 0.04). The decline in quadriceps strength was greatest in those with the highest strength at baseline (R -0.28 p = 0.02) and was not correlated with lung function, exacerbation frequency or steroid treatment. Decline in fat free mass was similarly higher in those with largest FFM at baseline (R = -0.31 p = 0.01) but was more strongly correlated with greater gas trapping (R = -0.4 p = 0.001). Patients with frequent exacerbations (>1 per year) (n = 36) experienced a greater decline in fat free mass compared to infrequent exacerbators (n = 28) -1.3(3.7)kg vs. +1.2(3.1)kg (p = 0.005), as did patients on maintenance oral steroids (n = 8) -2.8(3.3) kg vs. +0.2(3.5) kg (p = 0.024) whereas in those who stopped smoking (n = 7) fat free mass increased; +2.7(3.1) kg vs. -0.51(3.5) kg (p = 0.026).

CONCLUSION

Decline in fat free mass in COPD is associated with worse lung function, continued cigarette consumption and frequent exacerbations. Factors predicting progression of quadriceps weakness could not be identified from the present cohort.

Dietary advice for illness-related malnutrition in adults

BACKGROUND

Illness-related malnutrition has been reported in 10% to 55% of ill people in hospital and the community in areas of food sufficiency. Dietary advice encouraging the use of energy- and nutrient-rich foods rather than oral nutritional supplements has been suggested for managing illness-related malnutrition.

OBJECTIVES

To examine evidence that dietary advice to improve nutritional intake in adults with illness-related malnutrition improves survival, weight and anthropometry; to estimate the size of any additional effect of nutritional supplements given in combination with dietary advice.

SEARCH STRATEGY

Relevant publications were identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Additional studies were sought by contacting dietitians, clinicians and the manufacturers of nutritional supplements. Last search: October 2006

SELECTION CRITERIA

Randomised controlled trials of dietary advice in people with illness-related malnutrition compared with:(1) no advice;(2) oral nutritional supplements; and(3) dietary advice plus oral nutritional supplements.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility, methodological quality and extracted data.

MAIN RESULTS

Thirty-five studies (37 comparisons) met the inclusion criteria with 2648 randomised participants. Twelve trials (comparing dietary advice plus supplements if required with no advice) identified during searching are included as a separate comparison. Follow up ranged from 18 days to 24 months. No comparison showed a significant difference in mortality. Significant improvements in weight at three months were found for groups receiving dietary advice plus nutritional supplements compared with dietary advice alone, WMD 1.68 kg (95% CI 0.14 to 3.21) or no additional advice, WMD 1.97 (95% CI 0.07 to 3.86). There were significant improvements in grip strength and mid-arm muscle circumference in the advice plus supplement groups compared with dietary advice alone. It is uncertain whether nutritional supplements and dietary advice produce the same effects. No significant differences were found between groups for clinical outcomes. Few data were available for other outcomes.

AUTHORS' CONCLUSIONS

This review highlights the lack of evidence for the provision of dietary advice in managing illness-related malnutrition. Dietary advice plus nutritional supplements may be more effective than dietary advice alone or no advice in enhancing short-term weight gain, but whether this is sustainable, or whether survival and morbidity are improved remains uncertain. A large adequately-powered randomised controlled trial is needed comparing the efficacy of different therapies to increase dietary intake in people with illness-related malnutrition and examining the impact of this on clinical function and survival.