Exercise Capacity In Chronic Obstructive Pulmonary Disease Research Articles

Urban environment and physical activity and capacity in patients with chronic obstructive pulmonary disease

BackgroundPhysical activity and exercise capacity are key prognostic factors in chronic obstructive pulmonary disease (COPD) but their environmental determinants are unknown. ObjectivesTo test the association between urban environment and objective physical activity, physical activity experience and exercise capacity in COPD. MethodsWe studied 404 patients with mild-to-very severe COPD from a multi-city study in Catalonia, Spain. We measured objective physical activity (step count and sedentary time) by the Dynaport MoveMonitor, physical activity experience (difficulty with physical activity) by the Clinical visit-PROactive (C-PPAC) instrument, and exercise capacity by the 6-min walk distance (6MWD). We estimated individually (geocoded to the residential address) population density, pedestrian street length, slope of terrain, and long-term (i.e., annual) exposure to road traffic noise, nitrogen dioxide (NO2) and particulate matter (PM2.5). We built single- and multi-exposure mixed-effects linear regressions with a random intercept for city, adjusting for confounders. ResultsPatients were 85% male, had mean (SD) age 69 (9) years and walked 7524 (4045) steps/day. In multi-exposure models, higher population density was associated with fewer steps, more sedentary time and worse exercise capacity (−507 [95% CI: 1135, 121] steps, +0.2 [0.0, 0.4] h/day and −13 [-25, 0] m per IQR). Pedestrian street length related with more steps and less sedentary time (156 [9, 304] steps and −0.1 [-0.1, 0.0] h/day per IQR). Steeper slope was associated with better exercise capacity (15 [3, 27] m per IQR). Higher NO2 levels related with more sedentary time and more difficulty in physical activity. PM2.5 and noise were not associated with physical activity or exercise capacity. DiscussionPopulation density, pedestrian street length, slope and NO2 exposure relate to physical activity and capacity of COPD patients living in highly populated areas. These findings support the consideration of neighbourhood environmental factors during COPD management and the attention to patients with chronic diseases when developing urban and transport planning policies.

A basic tool to determine exercise capacity in COPD: 4-meter gait speed.

Determination of exercise capacity is crucial for chronic obstructive pulmonary disease (COPD) management since it is an indicator of life quality and mortality. Various previously defined tests, including the cardiopulmonary exercise test (CPET), the 6-minute walking test (6MWT), and the incremental shuttle walk test, are used to determine COPD patients' exercise capacity. However, they all have some disadvantages, such as time, personnel, and equipment requirements, limiting their daily practice use. Here, it was aimed to investigate the role of 4-meter gait speed (4mGS) in evaluating exercise capacity in COPD. We included 40-to-70-year-old COPD patients with no contraindications for exercise testing. We performed the tests at standard intervals without affecting each other's results. We also performed spirometry. We used the modified Medical Research Council Scale, COPD Assessment Test, and BODE index to determine the current status of individuals. Twenty-three (female/male= 2/21) subjects aged 58.1 ± 7.3 were included in the study. A statistically significant correlation was observed between 4mGS and peak VO2 values. There was also a statistically significant relationship between 4mGS and 6MWT distance. 4mGS correlated with CAT and BODE scores to represent the general medical status of patients. Considering its easy applicability and reproducibility, 4mGS seems to be a strong candidate for daily clinical use in monitoring the exercise capacity of COPD patients. Further studies in larger patient groups are needed to support these results.

Comparative Effectiveness of Western and Eastern Manual Therapies for Chronic Obstructive Pulmonary Disease: A Systematic Review and Network Meta-Analysis.

Background: Manual therapy (MT) is considered a promising adjuvant therapy for chronic obstructive pulmonary disease (COPD). Comparing the effectiveness among different Western and Eastern MTs being used for the management of COPD could potentially facilitate individualized management of COPD. This systematic review attempted to estimate the comparative effectiveness of Western and Eastern MTs for COPD patients using a network meta-analysis (NMA) methodology. Methods: Nine electronic databases were comprehensively searched for relevant randomized controlled trials (RCTs) published up to February 2021. Pair-wise meta-analysis and NMA were conducted on the outcomes of COPD, which included lung function and exercise capacity. Results: The NMA results from 30 included RCTs indicated that the optimal treatment for each outcome according to the surface under the cumulative ranking curve was massage, acupressure, massage, and tuina for forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC, and 6 min walking distance, respectively. Conclusions: MTs such as massage, acupressure, and tuina have shown comparative benefits for lung function and exercise capacity in COPD. However, the methodological quality of the included studies was poor, and the head-to-head trial comparing the effects of different types of MTs for COPD patients was insufficient. Therefore, further high-quality RCTs are essential.

The efficacy of manual therapy for chronic obstructive pulmonary disease: A systematic review.

BackgroundManual therapy (MT) can be beneficial in the management of chronic obstructive pulmonary disease (COPD). However, evidence of the efficacy of MT for COPD is not clear. Therefore, we aimed to review the effects of MT, including Chuna, in people diagnosed with COPD.MethodsMEDLINE via PubMed, EMBASE, The Cochrane Central Register of Controlled Trials (CENTRAL), China National Knowledge Database (CNKI), KoreaMed, Korean Medical Database (KMbase), and Oriental Medicine Advanced Searching Integrated System (OASIS) were searched. Randomized controlled trials (RCTs) and crossover RCTs were included. The main inclusion criteria were COPD diagnosis (forced expiratory volume in the first second [FEV1]/forced vital capacity [FVC] < 0.70). The primary outcomes were lung function and exercise capacity. The secondary outcomes were symptoms, quality of life (QoL), and adverse event (AE)s. Studies reporting one or both of the primary outcomes were included. The Cochrane RoB 2.0 tool was used to assess the risk of bias. Data synthesis and analysis were conducted according to the trial design.ResultsOf the 2564 searched articles, 13 studies were included. For the primary outcomes, the effect of MT on pulmonary function and exercise capacity in COPD was partly significant but could not be confirmed due to the limited number of studies included in the subgroups. For the secondary outcomes, no definitive evidence regarding the improvement of symptoms and QoL was found, and some minor adverse effects were reported.ConclusionsThere is insufficient evidence to support the role of MT in the management of COPD. High-quality studies are needed to thoroughly evaluate the effect of MT on COPD.

A double-blind randomised controlled trial of protein supplementation to enhance exercise capacity in COPD during pulmonary rehabilitation: a pilot study.

BackgroundPulmonary rehabilitation is a cost-effective management strategy in chronic obstructive pulmonary disease (COPD) which improves exercise performance and health-related quality of life. Nutritional supplementation may counter malnutrition and enhance pulmonary rehabilitation outcomes but rigorous evidence is absent. We aimed to investigate the effect of high-protein supplementation (Fortisip Compact Protein (FCP)) during pulmonary rehabilitation on exercise capacity.MethodsThis was a double-blind randomised controlled trial comparing FCP (intervention) with PreOp (a carbohydrate control supplement) in COPD patients participating in a pulmonary rehabilitation programme. Participants consumed the supplement twice a day during pulmonary rehabilitation and attended twice-weekly pulmonary rehabilitation sessions, with pre- and post-pulmonary rehabilitation measurements, including the incremental shuttle walk test (ISWT) distance at 6 weeks as the primary outcome. Participants’ experience using supplements was assessed.Results68 patients were recruited (intervention n=36 and control n=32). The trial was stopped early due to the COVID-19 pandemic. Although statistical significance was not reached, there was the suggestion of a clinically meaningful difference in the ISWT distance at 6 weeks favouring the intervention group (intervention 342±149 m (n=22) versus control 305±148 m (n=22); p=0.1). Individuals who achieved an improvement in the ISWT had a larger mid-thigh circumference at baseline (responders 62±4 cm versus nonresponders 55±6 cm; p=0.006). 79% of the patients were satisfied with the taste and 43% would continue taking the FCP.ConclusionsAlthough the data did not demonstrate a statistically significant difference in the ISWT, high-protein supplementation in COPD during pulmonary rehabilitation may result in a clinically meaningful improvement in exercise capacity and was acceptable to patients. Large, adequately powered studies are justified.

Effects of Pulmonary Hypertension on Exercise Capacity in Patients With Chronic Obstructive Pulmonary Disease

IntroductionThe impact of pulmonary hypertension (PH) on exercise tolerance in chronic obstructive pulmonary disease (COPD) has not been fully elucidated. It is necessary to characterize pulmonary hemodynamics in patients with moderate to severe COPD in order to improve their management. The aim of the study was to determine whether in COPD the presence of PH is associated with reduced exercise tolerance in a cohort of stable COPD patients. MethodsCross-sectional analysis of 174 COPD patients clinically stable: 109 without PH and 65 with PH (COPD-PH). We assessed socio-demographic data, lung function, quality of life, dyspnea, cardiopulmonary exercise testing (CPET), constant workload endurance time (CWET), and six-minute walk test (6MWT). We elaborated a logistic regression model to explore the impact of PH on exercise capacity in COPD patients. ResultsCOPD-PH patients showed lower exercise capacity both at maximal (CPET) (43(20) versus 68(27) Watts and 50(19)% versus 71(18)% predicted peak oxygen consumption (VO2peak), COPD-PH and COPD, respectively), and at submaximal tests (6MWT) (382(94) versus 486(95) m). In addition, the COPD-PH group had lower endurance time than the non-PH COPD group (265(113) s and 295(164) s, respectively). ConclusionsThe presence of PH is an independent factor that impairs exercise capacity in COPD.

Determinants of the diminished exercise capacity in patients with chronic obstructive pulmonary disease: looking beyond the lungs.

Peak oxygen uptake, a primary determinant of prognosis, mortality and quality of life, is diminished in patients with chronic obstructive pulmonary disease (COPD), with mounting evidence supporting an important role for peripheral dysfunction, particularly within skeletal muscle. In patients with severe COPD and activity-matched controls, muscle oxygen transport and utilization were assessed at peak effort during single-leg knee-extensor exercise (KE), where ventilation is assumed to be submaximal. This strategy removes ventilation as the major constraint to exercise capacity in COPD, allowing maximal muscle function to be attained and evaluated. During maximal KE, both convective arterial oxygen delivery to the skeletal muscle microvasculature and subsequent diffusive oxygen delivery to the mitochondria were diminished in patients with COPD compared to control subjects. These findings emphasize the importance of factors, beyond the lungs, that influence exercise capacity in this patient population and may, ultimately, influence the prognosis, mortality and quality of life for patients with COPD. Peak oxygen uptake ( ), a primary determinant of prognosis, mortality and quality of life, is diminished in patients with chronic obstructive pulmonary disease (COPD). Mounting evidence supports an important role of the periphery, particularly skeletal muscle, in the diminished with COPD. However, the peripheral determinants of have not been comprehensively assessed in this cohort. Thus, the hypothesis was tested that both muscle convective and diffusive oxygen (O2 ) transport, and therefore skeletal muscle peak O2 uptake ( ), are diminished in patients with COPD compared to matched healthy controls, even when ventilatory limitations (i.e. attainment of maximal ventilation) are minimized by using small muscle mass exercise. Muscle O2 transport and utilization were assessed at peak exercise from femoral arterial and venous blood samples and leg blood flow (by thermodilution) in eight patients with severe COPD (forced expiratory volume in 1s (FEV1 )±SEM=0.9±0.1l, 30% of predicted) and eight controls during single-leg knee-extensor exercise. Both muscle convective O2 delivery (0.44±0.06vs. 0.69±0.07lmin-1 , P<0.05) and muscle diffusive O2 conductance (6.6±0.8vs. 10.4±0.9mlmin-1 mmHg-1 , P<0.05) were ∼1/3 lower in patients with COPD than controls, resulting in an attenuated in the patients (0.27±0.04vs. 0.42±0.05lmin-1 , P<0.05). When cardiopulmonary limitations to exercise are minimized, the convective and diffusive determinants of , at the level of the skeletal muscle, are greatly attenuated in patients with COPD. These findings emphasize the importance of factors, beyond the lungs, that may ultimately influence this population's prognosis, mortality and quality of life.

Which is the best protocol and cut-off point in the 4-metre gait speed test to discriminate exercise capacity in COPD?

Objective To determine the discriminative capacity and cut-off point of different 4-metre gait speed test (4MGS) protocols in identifying preserved or reduced exercise capacity using the six-minute walk test (6MWT) in patients with Chronic Obstructive Pulmonary Disease (COPD); also, to compare 4MGS protocols and characteristics of individuals according to the best cut-off point. Methods We evaluated fifty-six patients with COPD, all of which were submitted to the assessment of anthropometric characteristics, pulmonary function (spirometry) and functional exercise capacity (6MWT and four protocols of the 4MGS). In the 4MGS test, patients were instructed to walk at normal pace and at maximum speed in a 4 meters course (4MGS 4m - usual pace and at maximum) and 8 meters course (4MGS 8m - usual pace and at maximum). Results Only the 4MGS 4m-maximum protocol was able to identify preserved exercise capacity in the 6MWT (AUC=0.70) with moderate correlation between them (r=0.52; P=0<0.0001). The cut-off point found in the 4MGS 4m-maximum was 1.27 m/s. Patients with preserved exercise capacity (4MGS 4m-maximum ≥1.27m/s) walker greater distances on the 6MWT in %pred (91±2 vs 76±3; P<0.0001). In the other comparisons involving gender, BMI, FEV1% pred and GOLD index there were no significant differences between the groups. In addition, the agreement of individuals classified as preserved and reduced exercise capacity in the 6MWT and 4MGS 4m-maximum was significant (P = 0.008). Conclusion The 4MGS 4m-maximum test can be used to discriminate preserved exercise capacity in patients with COPD and correlates with the 6MWT.

Effects of Pulmonary Hypertension on Exercise Capacity in Patients With Chronic Obstructive Pulmonary Disease

IntroductionThe impact of pulmonary hypertension (PH) on exercise tolerance in chronic obstructive pulmonary disease (COPD) has not been fully elucidated. It is necessary to characterize pulmonary hemodynamics in patients with moderate to severe COPD in order to improve their management. The aim of the study was to determine whether in COPD the presence of PH is associated with reduced exercise tolerance in a cohort of stable COPD patients. MethodsCross-sectional analysis of 174 COPD patients clinically stable: 109 without PH and 65 with PH (COPD-PH). We assessed socio-demographic data, lung function, quality of life, dyspnea, cardiopulmonary exercise testing (CPET), constant workload endurance time (CWET), and six-minute walk test (6MWT). We elaborated a logistic regression model to explore the impact of PH on exercise capacity in COPD patients. ResultsCOPD-PH patients showed lower exercise capacity both at maximal (CPET) (43(20) versus 68(27) Watts and 50(19)% versus 71(18)% predicted peak oxygen consumption (VO2peak), COPD-PH and COPD, respectively), and at submaximal tests (6MWT) (382(94) versus 486(95) m). In addition, the COPD-PH group had lower endurance time than the non-PH COPD group (265(113) s and 295(164) s, respectively). ConclusionsThe presence of PH is an independent factor that impairs exercise capacity in COPD.

Prevalence of comorbidities and impact on pulmonary rehabilitation outcomes.

BackgroundThe presence of comorbid conditions could impact performance in pulmonary rehabilitation (PR) programmes. We aimed to compare the comorbidity prevalence among those with chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD) and evaluate the impact on PR response.MethodsWe performed a retrospective cohort study, recording comorbidities for all patients with COPD or ILD referred to PR. Participants were classified as responders to PR if they met the minimal important difference for exercise capacity and health-related quality of life (HRQoL). The prevalence of comorbidities and impact on PR outcomes were compared by lung disease and by sex using a univariate analysis and multivariate logistic regression.ResultsThe mean number of comorbidities was similar among those with COPD (3.3±2.1, n=242) and ILD (3.2±1.9, n=66) (p>0.05). Females had a higher number of comorbidities than males in both COPD (p=0.001) and ILD (p=0.017) populations. Circulatory (64%) and endocrine/metabolic (45%) conditions were most common in COPD. In ILD, digestive (55%) and circulatory (53%) comorbidities were most prevalent. In people with ILD, those over 65 years, with musculoskeletal/connective tissue disease or circulatory disease were less likely to obtain meaningful improvements in exercise capacity. There was no impact of comorbidities on exercise capacity in COPD or on HRQoL in ILD.ConclusionsThe majority of patients with COPD or ILD enrolled in PR programmes have multiple comorbidities that may affect improvements in exercise capacity. PR programmes may be less effective for older adults with ILD and comorbid circulatory or musculoskeletal disease.

A web-based physical activity intervention benefits persons with low self-efficacy in COPD: results from a randomized controlled trial

Promoting physical activity (PA) is of top priority in chronic obstructive pulmonary disease (COPD). This study examines the influence of an internet-delivered intervention on the relationship between exercise self-efficacy and changes in PA, physical health, and exercise capacity in COPD. 112 U.S. Veterans with COPD were randomized to either a comparison (pedometer alone) or an intervention group (pedometer plus access to an internet-mediated PA intervention). There was a significant interaction between baseline exercise self-efficacy and randomization group on change in PA. In the comparison group, there was a significant relationship between higher baseline exercise self-efficacy and greater change in PA, whereas in the intervention group, improvements in PA were independent of level of baseline self-efficacy. Similar patterns were found with physical health and exercise capacity as outcomes. The use of an internet-mediated intervention significantly benefited persons with COPD who had low baseline self-efficacy to increase PA and physical health.Clinical trial registration The randomized clinical trial was registered on ClinicalTrials.gov (NCT01772082).

Using step counters to promote physical activity and exercise capacity in patients with chronic obstructive pulmonary disease: a meta-analysis.

Background:Although step counters are popularly employed for physical rehabilitation in chronic obstructive pulmonary disease (COPD) patients, their effectiveness is inconsistent and even questioned. This meta-analysis aimed to investigate whether step counter use increases physical activity or improves exercise capacity in COPD patients.Methods:Electronic databases were searched for randomized controlled trials that assessed the efficacy of step counter use in increasing physical activity or in improving exercise capacity. Data were aggregated using a random-effects model to get the overall effect sizes [standard mean difference (SMD) with 95% confidence interval (CI)], and subgroup analyses were performed.Results:A total of 15 trials enrolling 1316 patients with moderate to severe COPD were included. Step counter use increased physical activity compared with controls (SMD = 0.57, 95% CI 0.31–0.84), which is equal to a magnitude of 1026 steps/day in daily steps. It also enhanced exercise capacity with an effect size of 0.30 (95% CI 0.16–0.45), approximating to a magnitude of 11.6 m in the 6-min walking distance. Step counter use could augment physical activity (SMD = 0.64, 95% CI 0.19–1.08) and exercise capacity (SMD = 0.32, 95% CI 0.01–0.62) for patients receiving pulmonary rehabilitation. Yet it cannot enhance physical activity or exercise capacity in patients with severe COPD or among studies with intervention durations ⩾6 months (both p > 0.50).Conclusions:Step counter use increases physical activity and improves exercise capacity in COPD patients, at least in the short term, which supports the notion of recommending step counter use in COPD management.

Vitamin D Deficiency Is Associated with Rapid Decline in Exercise Capacity in Male Patients with Chronic Obstructive Pulmonary Disease

Background: Vitamin D is suggested to play a role in airway and systemic inflammation in chronic obstructive pulmonary disease (COPD). Low serum 25-hydroxyvitamin D (25-OHD) levels have been suggested to be associated with lower lung function and poorer exercise capacity in COPD. Objectives: The main purpose of this study was to investigate the effects of vitamin D deficiency on the change in exercise capacity in male COPD patients. Methods: A total of 156 male subjects were selected from the Korean Obstructive Lung Disease cohort. Vitamin D deficiency was subdivided into three subgroups: mild, moderate, and severe deficiency groups. Rapid decline was defined as an annual rate of change in exercise capacity ≥17 m. Exercise capacity was assessed by 6-minute walk distance (6MWD). Results: Significant differences were observed in the serum levels of 25-OHD, the number of patients with vitamin D sufficiency, and moderate-to-severe deficiency between rapid decliners (n = 40) and non-rapid decliners (n = 116). No differences were found between the groups for age, smoking status, lung function, and 6MWD. Multivariate analysis showed that vitamin D deficiency was independently related to rapid decline in exercise capacity (p = 0.028). A statistically significant difference was observed among the subgroups of vitamin D deficiency in terms of the change in exercise capacity (p < 0.001). The annual decline in exercise capacity was prominent in the severe deficiency group (23.1 m/year). Conclusion: This study shows that vitamin D deficiency is associated with rapid decline in exercise capacity in male patients with COPD.

Pulmonary Rehabilitation and Physical Activity in Patients with Chronic Obstructive Pulmonary Disease.

Physical inactivity is common in patients with chronic obstructive pulmonary disease (COPD) compared with age-matched healthy individuals or patients with other chronic diseases. Physical inactivity independently predicts poor outcomes across several aspects of this disease, but it is (at least in principle) treatable in patients with COPD. Pulmonary rehabilitation has arguably the greatest positive effect of any current therapy on exercise capacity in COPD; as such, gains in this area should facilitate increases in physical activity. Furthermore, because pulmonary rehabilitation also emphasizes behavior change through collaborative self-management, it may aid in the translation of increased exercise capacity to greater participation in activities involving physical activity. Both increased exercise capacity and adaptive behavior change are necessary to achieve significant and lasting increases in physical activity in patients with COPD. Unfortunately, it is readily assumed that this translation occurs naturally. This concise clinical review will focus on the effects of a comprehensive pulmonary rehabilitation program on physical activity in patients with COPD. Changing physical activity behavior in patients with COPD needs an interdisciplinary approach, bringing together respiratory medicine, rehabilitation sciences, social sciences, and behavioral sciences.

Right ventricular diastolic function and exercise capacity in COPD

BackgroundDecreased exercise capacity in chronic obstructive pulmonary disease (COPD) is incompletely explained by pulmonary pathologic and physiologic abnormalities. We evaluated the extent to which right ventricular diastolic function (RVDF) is associated with exercise capacity in COPD. MethodsFifty-one patients with COPD were evaluated by echocardiography, spirometry, and the 6 min walk test (6MWT). RVDF was assessed using 4 echocardiographic parameters: 1) the ratio of tricuspid valve (TV) early (E) and late (A) inflow velocities (TV E/A) 2) TV early tissue Doppler velocity (TV e′) 3) TV deceleration time (DT) and 4) the ratio of TV E and e′ velocities (TV E/e′). Multiple linear regression was used to examine the extent to which these parameters were associated with 6MWT distance. All models adjusted for age, sex, post-bronchodilator FEV1/FVC, resting heart rate, and use of supplemental O2 during 6MWT. A regression model was calculated for each of the 4 markers of RVDF. ResultsForty-seven percent of the sample had GOLD stage III or IV COPD. All 51 subjects had preserved left ventricular ejection fraction (LVEF, mean = 71.7%, SD = 7.8%). A higher TV E/A ratio was associated with increased 6MWT distance (p = 0.001). TV e′, TV DT and TV E/e′ did not have a statistically significant association with 6MWT distance in regression models. ConclusionsIn a cohort with moderate to severe COPD and normal LVEF, TV E/A was associated with 6MWT distance after adjusting for relevant demographic and medical covariates. RV diastolic dysfunction may independently contribute to exercise intolerance in COPD.

The relationship between sleep quality and functional exercise capacity in COPD.

Poor sleep is often associated with a series of health problems in patients with chronic obstructive pulmonary disease (COPD), but the relationship between sleep quality and functional exercise capacity has not been previously investigated. To evaluate the relationship between quality of sleep and functional exercise capacity in clinically stable COPD. One hundred three consecutive subjects with stable COPD were recruited. The subjects were assessed with the Pittsburgh Sleep Quality Index (PSQI) and divided into poor sleep group (PSQI >5) and good sleep group (PSQI ≤5). Subjects were also assessed with spirometry, 6-min walk distance (6MWD), oxygen saturation (SP O2 ), the Epworth Sleepiness Scale, Hamilton Depression Rating Scale, Hamilton Anxiety Rating Scale, COPD Assessment Test (CAT), Modified Medical Research Council dyspnea scale and quadriceps muscle function. Poor sleep was present in 43.69% of the patients with COPD. Subjects with poor sleep had shorter 6MWD (t = -3.588, P < 0.001), greater age (t = 2.519, P = 0.013), worse quality of life (t = 5.487, P < 0.001) and more depression (t = 6.576, P < 0.001) or anxiety (t = 4.245, P < 0.001) symptoms. 6MWD showed significant negative correlations with the PSQI global score (r = -0.373, P < 0.001). Multiple stepwise regresion analysis showed that PSQI global score was an independent psychological predictor of 6MWD, and 6MWD was the only physical predictor of PSQI total score in patients with COPD. There is a close relationship between sleep quality and functional exercise capacity in patients with COPD.

Ground-based walking training improves quality of life and exercise capacity in COPD.

This study was designed to determine the effect of ground-based walking training on health-related quality of life and exercise capacity in people with chronic obstructive pulmonary disease (COPD). People with COPD were randomised to either a walking group that received supervised, ground-based walking training two to three times a week for 8-10 weeks, or a control group that received usual medical care and did not participate in exercise training. 130 out of 143 participants (mean±sd age 69±8 years, forced expiratory volume in 1 s 43±15% predicted) completed the study. Compared to the control group, the walking group demonstrated greater improvements in the St George's Respiratory Questionnaire total score (mean difference -6 points (95% CI -10- -2), p<0.003), Chronic Respiratory Disease Questionnaire total score (mean difference 7 points (95% CI 2-11), p<0.01) and endurance shuttle walk test time (mean difference 208 s (95% CI 104-313), p<0.001). This study shows that ground-based walking training is an effective training modality that improves quality of life and endurance exercise capacity in people with COPD.

Hospital admissions and exercise capacity decline in patients with COPD

Exercise capacity declines with time and is an important determinant of health status and prognosis in patients with chronic obstructive pulmonary disease (COPD). We hypothesised that hospital admissions are associated with exercise capacity decline in these patients. Clinical and functional variables were collected for 342 clinically stable COPD patients. The 6-min walk distance (6MWD) was determined at baseline and after a mean±sd of 1.7±0.3 years. Information on hospitalisations during follow-up was obtained from centralised administrative databases. Linear regression was used to model changes in exercise capacity. Patients were mostly male (92%), with mean±sd age 67.9±8.6 years, post-bronchodilator forced expiratory volume in 1 s 54±17% predicted and baseline 6MWD 433±93 m. During follow-up, 6MWD decreased by 21.9±51.0 m·year(-1) and 153 (45%) patients were hospitalised at least once. Among patients admitted only for COPD-related causes (50% of those ever admitted), the proportion presenting a clinically significant loss of 6MWD was higher than in patients admitted for only nonrespiratory conditions (53% versus 29%, p=0.040). After adjusting for confounders, annual 6MWD decline was greater (26 m·year(-1), 95% CI 13-38 m·year(-1); p<0.001) in patients with more than one all-cause hospitalisation per year, as compared with those with no hospitalisations. Hospitalisations are related to a greater decline in exercise capacity in COPD.

Systematic Review and Meta-Analysis of Pulmonary Hypertension Specific Therapy for Exercise Capacity in Chronic Obstructive Pulmonary Disease

Some patients with chronic obstructive pulmonary disease (COPD) have pulmonary hypertension (PH) that adversely affects survival. We performed a systematic review and meta-analysis to assess whether PH-specific therapies have an effect for stable COPD. Data sources were Medline, EMBASE, Cochrane Central Register of Controlled Trials, Korea med and references from relevant publications. Randomized prospective trials that compared PH specific therapy in COPD for more than 6 weeks with placebo were included. The outcomes were the exercise capacity and adverse events. Four randomized controlled trials involving 109 subjects were included in the analysis. Two trials involved bosentan, one sildenafil and one beraprost. The studies varied in duration of treatment from 3 to 18 months. In a pooled analysis of four trials, exercise-capacity was not significantly improved with PH-specific treatment for COPD (risk ratio, -5.1; 95% CI, -13.0 to 2.8). COPD with overt PH significantly improved the exercise capacity (mean difference, 111.6; 95% CI, 63.3 to 159.9) but COPD with PH unknown did not (mean difference, 26.6; 95% CI, -24.3 to 77.5). There was no significant difference in hypoxemia (mean difference, 2.6; 95% CI, -3.7 to 8.8). PH specific treatments have a significant effect in improving exercise capacity in COPD with overt PH.

Cardiovagal baroreceptor sensitivity and peak oxygen consumption in chronic obstructive pulmonary disease (COPD)

Patients with chronic obstructive pulmonary disease (COPD) typically have reduced exercise capacity (VO2peak) and cardiovagal baroreflex sensitivity (BRS). The underlying mechanism for lower BRS in COPD is unclear. Exercise training has been shown to increase VO2peak and BRS sensitivity. Therefore, it was hypothesized that lower BRS in COPD would be related to VO2peak. COPD patients (n=14; Mean FEV1=59.4±33.9%predicted, age=70.9±8.8) and healthy controls (n=8; Mean FEV1=104.0±12.5%predicted, age=67.5±5.1) were recruited. None had diagnosed cardiovascular disease, diabetes or sleep apnea. VO2peak data were obtained from a cardiopulmonary exercise stress test. On a separate day resting heart rate and beat‐by‐beat blood pressure were measured. BRS was determined using the sequence method. We found lower BRS (7.2±3.8 vs. 14.8±9.7ms/mmHg; P=0.01) and VO2peak (19.6±4.0 vs. 31.1±9.3mL/kg/min; P&lt;0.001) in COPD, and a linear relationship in COPD and controls between VO2peak and BRS was observed (R2=0.24; P=0.02). Preliminary results indicate that the reduction of BRS is related to reduced exercise capacity in COPD. Funded by Canadian Institutes of Health Research.