Extrapulmonary effects of chronic obstructive pulmonary disease

An Italian Delphi Consensus on the Triple inhalation Therapy in Chronic Obstructive Pulmonary Disease

BACKGROUND

The management of chronic obstructive pulmonary disease (COPD) lacks standardization due to the diverse clinical presentation, comorbidities, and limited acceptance of recommended approaches by physicians. To address this, a multicenter study was conducted among Italian respiratory physicians to assess consensus on COPD management and pharmacological treatment.

METHODS

The study employed the Delphi process using the Estimate-Talk-Estimate method, involving a scientific board and expert panel. During a 6-month period, the scientific board conducted the first Delphi round and identified 11 broad areas of COPD management to be evaluated while the second Delphi round translated all 11 items into statements. The statements were subsequently presented to the expert panel for independent rating on a nine-point scale. Consensus was considered achieved if the median score was 7 or higher. Consistently high levels of consensus were observed in the first rating, allowing the scientific board to finalize the statements without requiring further rounds.

RESULTS

Topics generating substantial discussion included the pre-COPD phase, patient-reported outcomes, direct escalation from a single bronchodilator to triple therapy, and the role of adverse events, particularly pneumonia, in guiding triple therapy prescriptions. Notably, these topics exhibited higher standard deviations, indicating greater variation in expert opinions.

CONCLUSIONS

The study emphasized the significance that Italian pulmonologists attribute to managing mortality, tailoring treatments, and addressing cardiovascular comorbidities in COPD patients. While unanimous consensus was not achieved for all statements, the results provide valuable insights to inform clinical decision-making among physicians and contribute to a better understanding of COPD management practices in Italy.

20 years of neuromuscular electrical stimulation in COPD

Although a lung disease, COPD is also associated with extrapulmonary manifestations including, among others, limb muscle dysfunction. Limb muscle dysfunction is a key systemic consequence of COPD that impacts patients' physical activity, exercise tolerance, quality of life and survival. Deconditioning is the main mechanism underlying the development of limb muscle dysfunction in COPD, which can be partially improved with exercise. However, some patients may not be able to tolerate exercise because of incapacitating breathlessness or unwillingness to undertake whole-body exercise. Alternative training modalities that do not give rise to dyspnoea, such as neuromuscular electrical stimulation (NMES), are urged. Over the past 20 years, NMES in COPD has presented conflicting conclusions in meta-analysis. In this review, we try to understand the reason for this result by analysing possible biases and factors that brought conflicting conclusions. We discuss the population (the intervention group, but also the control group), the outcome measures, the frequency of stimulation, the rehabilitation protocol (i.e. NMES alone versus standard care/rehabilitation or NMES plus conventional exercise training versus conventional exercise training alone or NMES versus sham treatment) and the trial design. The main reason for this discrepancy is the lack of dedicated guidelines for NMES. Further research is urged to determine the optimal parameters for an NMES programme. Despite this, NMES appears to be an effective means of enhancing quadriceps strength and exercise capacity in COPD with the potential to break the vicious circle induced by the disease and COPD patients' lifestyle.

Clinical Efficacy of Mobile App-Based, Self-Directed Pulmonary Rehabilitation for Patients With Chronic Obstructive Pulmonary Disease: Systematic Review and Meta-Analysis

Background

Pulmonary rehabilitation is well known to improve clinical symptoms (including dyspnea), quality of life, and exercise capacity in patients with chronic obstructive pulmonary disease (COPD). However, researchers have reported difficulties in practicing center-based pulmonary rehabilitation. Recently, mobile app-based pulmonary rehabilitation has become available in clinical practice. We investigated the clinical outcomes of mobile app-based pulmonary rehabilitation in patients with COPD.

Objective

The objective of our study was to evaluate the clinical efficacy of mobile app-based pulmonary rehabilitation versus conventional center-based pulmonary rehabilitation for patients with COPD, using a systematic review and meta-analysis.

Methods

A systematic search of the literature published between January 2007 and June 2023 was performed, using the PubMed, Embase, Cochrane, and CINAHL databases to identify relevant randomized controlled trials involving patients with COPD. Pulmonary rehabilitation programs needed to provide an exercise program on a smartphone app. Study outcomes, including exercise capacity, symptom scores, quality of life, and hospitalization, were evaluated. The meta-analysis evaluated mean differences in 6-minute walk test distances (6MWDs), COPD Assessment Test (CAT) scores, modified Medical Research Council (mMRC) dyspnea scale scores, St. George Respiratory Questionnaire (SGRQ) scores, and risk ratios for hospitalization resulting from disease exacerbation.

Results

Of the 1173 screened studies, 10 were included in the systematic review and 9 were included in the meta-analysis. Further, 6 studies were multicenter studies. There were a total of 1050 participants, and most were aged ≥65 years. There were discrepancies in the baseline participant characteristics, smartphone apps, interventions, and study outcomes among the included studies. In the meta-analysis, 5 studies assessed 6MWDs (mean difference 9.52, 95% CI -3.05 to 22.08 m), 6 studies assessed CAT scores (mean difference -1.29, 95% CI -2.39 to -0.20), 3 studies assessed mMRC dyspnea scale scores (mean difference -0.08, 95% CI -0.29 to 0.13), 2 studies assessed SGRQ scores (mean difference -3.62, 95% CI -9.62 to 2.38), and 3 studies assessed hospitalization resulting from disease exacerbation (risk ratio 0.65, 95% CI 0.27-1.53). These clinical parameters generally favored mobile app-based pulmonary rehabilitation; however, a statistically significant difference was noted only for the CAT scores (P=.02).

Conclusions

Despite some discrepancies in the baseline participant characteristics and interventions among studies, mobile app-based pulmonary rehabilitation resulted in favorable exercise capacity, symptom score, quality of life, and hospitalization outcomes when compared with conventional pulmonary rehabilitation. In the meta-analysis, the CAT scores of the mobile app-based pulmonary rehabilitation group were significantly lower than those of the control group (P=.02). In real-world practice, mobile app-based pulmonary rehabilitation can be a useful treatment option when conventional center-based pulmonary rehabilitation is not feasible.

Efficacy of aerobic training and resistance training combined with external diaphragm pacing in patients with chronic obstructive pulmonary disease: A randomized controlled study

OBJECTIVE

To evaluate the efficacy of aerobic training, resistance training combined with external diaphragm pacing in patients with chronic obstructive pulmonary disease.

DESIGN

Randomized controlled trial.

SETTING

The Fourth Rehabilitation Hospital of Shanghai, China.

PARTICIPANTS

82 (67.0  ±  6.5 years, 59.8% male) patients with stable chronic obstructive pulmonary disease were randomized to intervention group 1 (n  =  27), intervention group 2 (n  =  28), and control group (n  =  27).

INTERVENTION

Intervention group 1 received aerobic and resistance training, while intervention group 2 received additional external diaphragm pacing. Control group received aerobic training only.

MAIN MEASURES

1-year follow-up of physical activity, body composition, respiratory function and diaphragm function.

RESULTS

Intervention groups 1 and 2 showed statistically improvements in the difference value compared with control group in terms of 6-min walk distance (-95.28  ±  20.09 and -101.92  ±  34.91 vs -63.58  ±  23.38), forced expiratory volume in 1 s (-0.042  ±  0.027 and -0.130  ±  0.050 vs -0.005  ±  0.068), fat-free mass (-2.11  ±  3.74 and -3.82  ±  3.74vs 0.28  ±  1.49) and chronic obstructive pulmonary disease assessment test value (2.16  ±  0.85 and 2.38  ±  1.02 vs 1.50  ±  0.93). Intervention group 2 showed significant difference in arterial oxygen pressure (-4.46  ±  3.22 vs -1.92  ±  3.45), diaphragm excursion during deep breaths (-0.82  ±  0.74 vs -0.38  ±  0.29), and diaphragm thickness fraction (-8.77  ±  3.22 vs -4.88  ±  2.69) compared with control group.

CONCLUSION

The combination of aerobic training, resistance training, and external diaphragm pacing obtained significant improvements in physical activity, respiratory function, body composition, arterial oxygen pressure, and diaphragm function in patients with chronic obstructive pulmonary disease.

TRIAL REGISTRATION

ChiCTR1800020257, www.chictr.org.cn/index.aspx.

Trabecular bone score in active or former smokers with and without COPD

BACKGROUND

Smoking is a recognized risk factor for osteoporosis. Trabecular bone score (TBS) is a novel texture parameter to evaluate bone microarchitecture. TBS and their main determinants are unknown in active and former smokers.

OBJECTIVE

To assess TBS in a population of active or former smokers with and without Chronic Obstructive Pulmonary Disease (COPD) and to determine its predictive factors.

METHODS

Active and former smokers from a pulmonary clinic were invited to participate. Clinical features were recorded and bone turnover markers (BTMs) measured. Lung function, low dose chest Computed Tomography scans (LDCT), dual energy absorptiometry (DXA) scans were performed and TBS measured. Logistic regression analysis explored the relationship between measured parameters and TBS.

RESULTS

One hundred and forty five patients were included in the analysis, 97 (67.8%) with COPD. TBS was lower in COPD patients (median 1.323; IQR: 0.13 vs 1.48; IQR: 0.16, p = 0.003). Regression analysis showed that a higher body mass index (BMI), younger age, less number of exacerbations and a higher forced expiratory volume-one second (FEV1%) was associated with better TBS (β = 0.005, 95% CI:0.000-0.011, p = 0.032; β = -0.003, 95% CI:-0.007(-)-0.000, p = 0.008; β = -0.019, 95% CI:-0.034(-)-0.004, p = 0.015; β = 0.001, 95% CI:0.000-0.002, p = 0.012 respectively). The same factors with similar results were found in COPD patients.

CONCLUSIONS

A significant proportion of active and former smokers with and without COPD have an affected TBS. BMI, age, number of exacerbations and the degree of airway obstruction predicts TBS values in smokers with and without COPD. This important information should be considered when evaluating smokers at risk of osteoporosis.

A Comparison of Pain, Fatigue, Dyspnea and their Impact on Quality of Life in Pulmonary Rehabilitation Participants with Chronic Obstructive Pulmonary Disease

In addition to dyspnea and fatigue, pain is a prevalent symptom in chronic obstructive pulmonary disease (COPD). Understanding the relative prevalence, magnitude, and interference with aspects of daily living of these symptoms can improve COPD management. Therefore, the purposes of this study were to: (1) compare the prevalence and magnitude of dyspnea, fatigue, and pain and how each limits aspects of daily living; (2) determine the association between pain and the other two symptoms; and (3) assess the impact of these symptoms on quality of life in COPD. Participants were recruited from pulmonary rehabilitation programs. Pain, dyspnea, and fatigue were measured using the Brief Pain Inventory (BPI), Brief Fatigue Inventory (BFI), and Dyspnea Inventory (DI), respectively. Quality of life was measured using the Clinical COPD Questionnaire (CCQ). The prevalence of dyspnea, fatigue, and pain were 93%, 77%, and 74%, respectively. Individuals with COPD reported similar severity scores of the three symptoms. Dyspnea interfered with general activity more than pain (F_1.7,79.9 = 3.1, p < 0.05), whilst pain interfered with mood (F_{1.8, 82.7} = 3.6, p < 0.05) and sleep (F_1,46 = 7.4, p < 0.01) more than dyspnea and fatigue. These three symptoms were moderately-to-highly correlated with each other (ρ = 0.49-0.78, p < 0.01) and all individually impacted quality of life. In summary, pain is a common symptom in addition to dyspnea and fatigue in COPD; all three interfere similarly among aspects of daily living with some exceptions. Accordingly, management of COPD should include a multifaceted approach that addresses pain as well as dyspnea and fatigue.

Efficacy of an mHealth intervention to stimulate physical activity in COPD patients after pulmonary rehabilitation

Physical inactivity in patients with chronic obstructive pulmonary disease (COPD) is associated with poor health status and increased disease burden. The present study aims to test the efficacy of a previously developed mobile (m)Health intervention to improve or maintain physical activity in patients with COPD after pulmonary rehabilitation.

A randomised controlled trial was performed in 32 physiotherapy practices in the Netherlands. COPD patients were randomised into intervention or usual care groups. The intervention consisted of a smartphone application for the patients and a monitoring website for the physiotherapists. Measurements were performed at 0, 3, 6 and 12 months. Physical activity, functional exercise capacity, lung function, health-related quality of life and body mass index were assessed.

157 patients started the study and 121 completed it. There were no significant positive effects of the intervention on physical activity (at 0 months: intervention 5824±3418 steps per weekday, usual care 5717±2870 steps per weekday; at 12 months: intervention 4819±2526 steps per weekday, usual care 4950±2634 steps per weekday; p=0.811) or on the secondary end-points. There was a significant decrease over time in physical activity (p<0.001), lung function (p<0.001) and mastery (p=0.017), but not in functional exercise capacity (p=0.585).

Although functional exercise capacity did not deteriorate, our mHealth intervention did not improve or maintain physical activity in patients with COPD after a period of pulmonary rehabilitation.

Influence of diaphragmatic mobility on hypercapnia in patients with chronic obstructive pulmonary disease

A reduction in diaphragm mobility has been identified in patients with chronic obstructive pulmonary disease (COPD) and has been associated with a decline in pulmonary function parameters. However, little information exists regarding the potential role of diaphragm mobility on hypercapnia in COPD. A new method of assessing the mobility of the diaphragm, using ultrasound, has recently been validated. The purpose of the present study was to investigate the relationship between diaphragm mobility and pulmonary function parameters, as well as that between arterial blood gas values and diaphragm mobility, in COPD patients. Thirty seven COPD patients were recruited for pulmonary function test, arterial blood gas analysis and diaphragm mobility using ultrasound to measure the craniocaudal displacement of the left branch of the portal vein. There were significant negative correlations between diaphragmatic mobility and P(a)CO(2) (r = -0.373, P = 0.030). Diaphragmatic mobility correlated with airway obstruction (FEV(1), r = 0.415, P = 0.011) and with ventilatory capacity (FVC, r = 0.302, P = 0.029; MVV, r = 0.481, P = 0.003). Diaphragmatic mobility also correlated significantly with pulmonary hyperinflation. No relationship was observed between diaphragm mobility and P(a)O(2) (r = -0.028, P = 0.873). These findings support a possibility that the reduction in diaphragm mobility relates to hypercapnia in COPD patients.

Diaphragmatic dysfunction and mortality in patients with COPD

OBJECTIVE

To determine whether COPD patients with diaphragmatic dysfunction present higher risk of mortality than do those without such dysfunction.

METHODS

We evaluated pulmonary function, diaphragm mobility and quality of life, as well as determining the Body mass index, airway Obstruction, Dyspnea, and Exercise capacity (BODE) index, in 42 COPD patients. The patients were allocated to two groups according to the degree to which diaphragm mobility was impaired: low mobility (LM; mobility < 33.99 mm); and high mobility (HM; mobility > 34.00 mm). The BODE index and the quality of life were quantified in both groups. All patients were followed up prospectively for up to 48 months in order to determine the number of deaths resulting from respiratory complications due to COPD.

RESULTS

Of the 42 patients evaluated, 20 were allocated to the LM group, and 22 were allocated to the HM group. There were no significant differences between the groups regarding age, lung hyperinflation or quality of life. However, BODE index values were higher in the LM group than in the HM group (p = 0.01). During the 48-month follow-up period, there were four deaths within the population studied, and all of those deaths occurred in the LM group (15.79%; p = 0.02).

CONCLUSIONS

These findings suggest that COPD patients with diaphragmatic dysfunction, characterized by low diaphragm mobility, have a higher risk of death than do those without such dysfunction.

Prevalence and predictors of vertebral fracture in patients with chronic obstructive pulmonary disease

OBJECTIVES

Patients with COPD are at risk for osteoporosis-related vertebral compression fractures (VCF) which predispose to more fractures and worsening pulmonary function. Our objectives were to: 1 document VCF prevalence in COPD patients; and 2 determine the independent correlates of VCF.

METHODS

From 2004-2006, we prospectively recruited consecutive consenting COPD patients presenting with acute exacerbation at three Canadian Emergency Departments (ED). We collected clinical and pulmonary function data. Primary outcome was radiologist documented VCF on chest radiograph. Multivariable logistic regression was used for all adjusted analyses.

RESULTS

Overall, 245 patients were studied; 37% were >or=75 years and 44% were women. Prevalence of VCF documented by chest radiograph was 22 of 245 (9%; 95%CI 6-13%). Almost half (10 of 22 [43%]) of VCF patients were not treated for osteoporosis and all 10 received oral steroids. Compared to patients without fractures, those with VCF were older (p=0.014), had COPD of longer duration (p=0.09) and greater severity (mean FEV(1) 0.9 vs 1.1L; p=0.05), and had lower body mass index [BMI] (median 26 vs 28; p=0.01). Across BMI quartiles (from heaviest [median 37] to lightest [median 21]) the prevalence of VCF progressively increased (2%, 8%, 10%, 21%; p<0.001). In analyses adjusted for age, sex, and COPD duration, the only independent correlate of VCF was BMI: VCF increased as BMI decreased from heaviest (OR=1) to lightest (OR=11.0) quartiles (p=0.025).

CONCLUSIONS

Almost one-tenth of COPD patients presenting with acute exacerbation have chest radiographs documenting VCF. About half of patients with VCF were not treated for osteoporosis, but all were started on oral steroids. Our findings suggest chest radiograph reports may represent an important case-finding tool for VCF, particularly in underweight patients with COPD.

Prevalence and progression of osteoporosis in patients with COPD: results from the TOwards a Revolution in COPD Health study

BACKGROUND

Osteoporosis is common in patients with COPD, but its prevalence and progression are not well characterized. Concerns have been raised over the possible deleterious effect of long-term therapy with inhaled corticosteroids (ICSs) on bone density in this population. Here, we investigated the long-term effects of therapy with fluticasone propionate (FP) alone, salmeterol (SAL) alone, and a SAL/FP combination (SFC) on bone mineral density (BMD) and bone fractures in patients with moderate-to-severe COPD in the TOwards a Revolution in COPD Health (TORCH) study.

METHODS

A randomized, double-blind, parallel-group, placebo-controlled study conducted at 88 US centers involving 658 patients (a subset of 6,184 international subjects in TORCH). Therapy with placebo, SAL (50 microg), FP (500 microg), or SFC (SAL 50 microg/FP 500 microg) twice daily was administered for 3 years. Baseline and yearly measurements of BMD at the hip and lumbar spine were performed. The incidence of traumatic and nontraumatic bone fractures was recorded.

RESULTS

At baseline, 18% of men and 30% of women had osteoporosis, and 42% of men and 41% of women had osteopenia based on BMD assessments. Forty-three percent of subjects completed all testing. The changes in BMD at the hip and lumbar spine over 3 years were small. No significant differences were observed between treatment arms (adjusted mean percent change from baseline at hip was -3.1% for placebo, -1.7% for SAL, -2.9% for FP, and -3.2% for SFC therapy, respectively; while, the corresponding changes for the lumbar spine were 0, 1.5%, -0.3%, and -0.3% for placebo, respectively, SAL, FP, and SFC therapy). The incidence of fractures was low and was similar for all treatments (5.1% to 6.3%).

CONCLUSIONS

Osteoporosis is highly prevalent in patients with COPD, irrespective of gender. In the TORCH study, no significant effect on BMD was detected for ICS therapy compared with placebo.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NTC00268216.

Clinical Safety of Long-Acting β2-Agonist and Inhaled Corticosteroid Combination Therapy in COPD

Long-acting beta2-agonist (LABA) and inhaled corticosteroid (ICS) combination therapy is recommended by international treatment guidelines for COPD. The current literature concerning the safety of LABAs and ICS, both as monotherapies and in combination, in patients with COPD is reviewed. Bronchodilators such as LABAs are key treatments for COPD due to their effects on bronchial smooth muscle and airflow limitation. LABAs are well-tolerated in patients with COPD, with a low incidence of reported adverse events (AEs). Most AEs associated with LABA use are due to systemic exposure and include muscle tremor and cardiac effects. Placebo-controlled studies in patients with COPD demonstrate that there is no increase in risk of cardiac AEs with LABA therapy. ICS therapy targets airway inflammation in COPD, and is associated with a reduction in the frequency of COPD exacerbations, and improvements in symptoms, lung function and health status. Localized effects such as oropharyngeal irritation are common with ICS, but are not considered to be serious. Potential ocular effects with ICS therapy in patients with COPD have been identified and require further investigation. Rare, but more serious AEs related to ICS use are the effects on bone and the suppression of endogenous cortisol production; however, the clinical relevance of these effects is unclear. Clinical data indicate that LABA/ICS combination therapy is more effective in COPD than either agent used alone and is not associated with any additional AEs.

Impact of hospitalisations for exacerbations of COPD on health-related quality of life

Exacerbations of chronic obstructive pulmonary disease (COPD) impair health-related quality of life (HRQoL). It is unknown whether exacerbations requiring hospitalisation have an impact on HRQoL. 611 ambulatory COPD patients were prospectively identified. The average age (SD) was 65.5 (8.6), FEV(1) (SD) was 52% (14%) of the predicted value. All patients completed the Saint George's Respiratory Questionnaire (SGRQ) and the Medical Outcomes Study Short Form (SF-36) questionnaire at the beginning of the study. After five years of follow-up, the 391 survivors again completed these HRQoL instruments. No changes in HRQoL were observed among patients not hospitalised for COPD exacerbations. Those hospitalised during follow-up experienced significant declines in HRQoL. The largest changes were observed among patients with >or=3 hospitalisations, with a 13.6 unit increase in the total SGRQ and a 10.5 unit decrease in the physical component summary scale of the SF-36. Similar changes were observed among patients with FEV(1)>or=50% at baseline. In the multivariate analysis, after adjustment by FEV(1%), age, comorbidities, and HRQoL in the respective HRQoL domain at baseline, hospitalisations were an independent predictor of the change in HRQoL. Hospitalisations for exacerbations of COPD have an independent and negative impact on the evolution of HRQoL, regardless of COPD severity.

Double deficiency of tetraspanins CD9 and CD81 alters cell motility and protease production of macrophages and causes chronic obstructive pulmonary disease-like phenotype in mice

CD9 and CD81 are closely related tetraspanins that regulate cell motility and signaling by facilitating the organization of multimolecular membrane complexes, including integrins. We show that CD9 and CD81 are down-regulated in smoking-related inflammatory response of a macrophage line, RAW264.7. When functions of CD9 and CD81 were ablated with monoclonal antibody treatment, small interfering RNA transfection, or gene knock-out, macrophages were less motile and produced larger amounts of matrix metalloproteinase (MMP)-2 and MMP-9 than control cells in vitro. In line with this, CD9/CD81 double-knock-out mice spontaneously developed pulmonary emphysema, a major pathological component of chronic obstructive pulmonary disease (COPD). The mutant lung contained an increased number of alveolar macrophages with elevated activities of MMP-2 and MMP-9 and progressively displayed enlarged airspace and disruption of elastic fibers in the alveoli. Secretory cell metaplasia, a finding similar to goblet cell metaplasia in cigarette smokers, was also observed in the epithelium of terminal bronchioles. With aging, the double-knockout mice showed extrapulmonary phenotypes, including weight loss, kyphosis, and osteopenia. These results suggest that the tetraspanins CD9 and CD81 regulate cell motility and protease production of macrophages and that their dysfunction may underlie the progression of COPD.

Brain perfusion abnormalities in chronic obstructive pulmonary disease: comparison with cognitive impairment

OBJECTIVES

To clarify cerebral perfusion distribution and cognitive functions in patients with chronic obstructive pulmonary disease (COPD) according to the hypoxia levels and to assess if there is a relationship between cognitive impairment and cerebral perfusion index.

PATIENTS AND METHODS

Eight patients with stable hypoxemic COPD (HC), 10 patients with stable nonhypoxemic COPD (NHC), and 10 age-matched healthy volunteers participated in the study. All subjects underwent a complete neuropsychological assessment with the mental deterioration battery (MDB), Wechsler memory scale-revised (WMS-R), color trail test (CCT), and grooved pegboard test (GPT). SPECT examination with Tc-99m HMPAO was performed in all patients and controls. Quantitative analysis was performed by a region of interest (ROI)-based method.

RESULTS

The scores of verbal memory, delayed recall and attention were significantly lower in COPD patients (p < 0.01). The scores of other subtests were similar in patients and controls. Comparing NHC patients to HC groups showed that verbal memory was impaired in both groups, but delayed recall and attention scores were significantly worse in HC patients than NHC patients. Perfusion indexes on frontal ROIs in NHC patients and frontal and parietal ROIs in HC patients showed significant decreases. Our scintigraphic findings were correlated with the results of neuropsychological tests.

CONCLUSIONS

Our results demonstrate that cerebral perfusion is significantly altered in COPD patients. Hypoxemic patients showed more deterioration in cerebral perfusion and cognitive performance than nonhypoxemic patients. The relationship between decreased perfusion and cognitive impairment and the clinical significance of these results require further studies in larger populations.

Exercise Capacity Deterioration in Patients With COPD

BACKGROUND

Although exercise capacity is an important outcome measure in patients with COPD, its longitudinal course has not been analyzed in comparison to the change in pulmonary function.

PURPOSES

To examine how exercise capacity would deteriorate over time in patients with COPD, and what factors would contribute to it.

METHODS

A total of 137 male outpatients with moderate-to-very-severe COPD were examined. The average age was 69.0 +/- 6.6 years (+/- SD), and the mean postbronchodilator FEV(1) was 45.9 +/- 15.4% predicted. Progressive cycle ergometry and pulmonary function testing were performed at entry, and every 6 months thereafter over 5 years. Due to the presence of missing data, a mixed-effect model analysis was then used to estimate the longitudinal changes in various clinical parameters.

RESULTS

Peak oxygen uptake (Vo(2)), peak minute ventilation (Ve), and peak tidal volume (Vt) during exercise declined significantly over time (p < 0.0001), which was no less rapid than the deterioration in FEV(1). The mean decline rates for peak Vo(2) were 32 +/- 60 mL/min/yr and 0.5 +/- 1.0 mL/min/kg/yr. Multiple regression analysis revealed that the changes in peak Ve, peak Vt, and peak respiratory rates were significant predictors for the change in peak Vo(2).

CONCLUSION

We demonstrated clear evidence of measurable and progressive deterioration in exercise capacity in COPD patients, which was no less rapid than the decline in airflow limitation. Dynamic ventilatory constraints during exercise also deteriorated over time, which most significantly contributed to this exercise capacity deterioration. In addition to pulmonary function, the longitudinal follow-up of exercise capacity is important not to miss the overall deterioration in COPD.

Asthma and COPD: differences and similarities. With special reference to the usefulness of budesonide/formoterol in a single inhaler (Symbicort) in both diseases

Asthma and chronic obstructive pulmonary disease (COPD) both have a high prevalence worldwide and yet each condition remains underdiagnosed. Despite a number of common features, these inflammatory respiratory syndromes have distinct clinical outcomes. COPD represents a greater economic burden than asthma because it has a less favourable prognosis and is associated with greater morbidity and mortality. Therefore, it is important to distinguish between these two diseases at an early stage, so that appropriate therapy can be prescribed to prevent deterioration. However, effective treatments that may be used in both conditions can minimise the effects of misdiagnosis and maximise the impact of treatment without the associated complexity when both conditions occur together. The current review summarises the differences and similarities of asthma and COPD, in terms of risk factors, pathophysiology, symptoms and diagnosis, to provide greater understanding of the role of budesonide/formoterol in a single inhaler in both diseases.

Reversal of Chronic Obstructive Pulmonary Disease-Associated Weight Loss

Poor nutritional status is associated with an increased incidence of morbidity and mortality in patients with chronic obstructive pulmonary disease (COPD). While a number of factors have been shown to produce tissue catabolism, no single mechanism has been clearly identified as a primary cause for weight loss in patients with severe COPD. Without a clear understanding of the aetiology of weight loss, therapeutic strategies to reverse this process have historically been unsuccessful. A review of recent studies allows consideration of a model of mechanisms of weight loss. This model includes multiple pathways that may be activated singly or simultaneously to cause loss of weight, specifically lean body mass. These include energy imbalances, elevated levels of cytokines, tissue hypoxia and the effects of cocorticosteroid therapy. To date, interventional studies that have looked at newer pharmacotherapies such as growth hormone and anabolic steroids in patients with COPD who are losing weight have not demonstrated reversal of weight loss or improvement in nutritional status. Currently, early identification of patients at risk for weight loss and aggressive nutritional supplementation coupled with an exercise programme has demonstrated the greatest benefit. However, with increasing understanding of the mechanisms that may be implicated, new targets for therapies are being identified. Of particular research interest are molecules such as leukotrienes, hormones, tumour necrosis factor-alpha and acute-phase proteins, which are noted to be elevated in some patients with COPD-associated weight loss. Currently, inhibitors to some of these inflammatory substances are used therapeutically in other chronic illnesses such as rheumatoid arthritis and cancer cachexia. Future research may investigate their usefulness in COPD and direct new therapies that target the processes contributing to weight loss in these patients.

Heterozygous deficiency of hypoxia-inducible factor-2alpha protects mice against pulmonary hypertension and right ventricular dysfunction during prolonged hypoxia

Chronic hypoxia induces pulmonary vascular remodeling, leading to pulmonary hypertension, right ventricular hypertrophy, and heart failure. Heterozygous deficiency of hypoxia-inducible factor-1alpha (HIF-1alpha), which mediates the cellular response to hypoxia by increasing expression of genes involved in erythropoiesis and angiogenesis, has been previously shown to delay hypoxia-induced pulmonary hypertension. HIF-2alpha is a homologue of HIF-1alpha and is abundantly expressed in the lung, but its role in pulmonary hypertension remains unknown. Therefore, we analyzed the pulmonary response of WT and viable heterozygous HIF-2alpha-deficient (Hif2alpha(+/-)) mice after exposure to 10% O(2) for 4 weeks. In contrast to WT mice, Hif2alpha(+/-) mice were fully protected against pulmonary hypertension and right ventricular hypertrophy, unveiling a critical role of HIF-2alpha in hypoxia-induced pulmonary vascular remodeling. Pulmonary expression levels of endothelin-1 and plasma catecholamine levels were increased threefold and 12-fold respectively in WT but not in Hif2alpha(+/-) mice after hypoxia, suggesting that HIF-2alpha-mediated upregulation of these vasoconstrictors contributes to the development of hypoxic pulmonary vascular remodeling.

Analysis of the factors related to mortality in chronic obstructive pulmonary disease: role of exercise capacity and health status

In this study, we analyzed the relationships of exercise capacity and health status to mortality in patients with chronic obstructive pulmonary disease (COPD). We recruited 150 male outpatients with stable COPD with a mean postbronchodilator FEV1 at 47.4% of predicted. Their pulmonary function, progressive cycle ergometry, and health status using the Chronic Respiratory Disease Questionnaire, the St. George's Respiratory Questionnaire (SGRQ), and the Breathing Problems Questionnaire were measured at entry. Among 144 patients who were available for the 5-year follow-up, 31 had died. Univariate Cox proportional hazards analysis revealed that the SGRQ total score and the Breathing Problems Questionnaire were significantly correlated with mortality; however, with the Chronic Respiratory Disease Questionnaire, the total score was not significantly correlated. Multivariate Cox proportional hazards analysis revealed that the peak oxygen uptake and the SGRQ total score were both predictive of mortality, independent of FEV1 and age. Stepwise Cox proportional hazards analysis revealed that the peak oxygen uptake was the most significant predictor of mortality. We found that exercise capacity and health status were significantly correlated with mortality, although different health status measures had different abilities to predict mortality. These results will have a potentially great impact on the multidimensional evaluation of disease severity in COPD.