Assessment of work performance in asthma for determination of cardiorespiratory fitness and training capacity

Association of Physical Activity with Asthma and Chronic Obstructive Pulmonary Disease and Mediation of Frailty: Mendelian Randomization Analyses

Background

The existence of an association between physical activity (PA) and asthma and chronic obstructive pulmonary disease (COPD) has been confirmed in observational studies. Therefore, it is necessary to reveal whether there is a risk-effect relationship between physical activity and asthma and COPD through Mendelian randomization (MR) analysis.

Materials and Methods

Univariate Mendelian randomization (UVMR) analyses were performed to examine the associations between moderate to vigorous physical activity (MVPA), vigorous physical activity (VPA), accelerometer-assessed physical activity (AA), and strenuous exercise or other exercise (SSOE) with asthma and COPD. The methods of analysis were dominated by Inverse Variance-Weighted (IVW), Weighted median (WM), and MR-Egger methods. In addition, multivariate Mendelian randomization (MVMR) analyses were performed to correct the effects of four types of physical activity on asthma and COPD. Finally, potential mediating effect relationships were identified through mediation analyses.

Results

The results of Univariate Mendelian randomization analysis showed that SSOE could reduce the risk of asthma and COPD(asthma: OR=0.15,95% CI=0.04-0.58, P=0.006; COPD: OR=0.05, 95% CI=0.01-0.33, P=0.002). The results of the Multivariate Mendelian randomization analysis showed that SSOE was still able to reduce the risk of asthma and COPD after adjusting for the effects of different types of physical activity(asthma: 95% CI=-2.77--0.31, P=0.014; COPD: 95% CI=-4.00--0.50, P=0.012). Mediation analyses showed that frailty intervened in the causal relationship between physical activity and asthma and chronic obstructive pulmonary disease.

Conclusion

SSOE is a protective factor for asthma and COPD in the European population, while frailty plays a mediating role.

Effect of Bicycle Ergometer Training and Nordic Walking Training on Improving Functional Exercise Capacity in Asthma Patients

Introduction Asthma is a chronic respiratory condition characterized by inflammation of the airway leading to breathlessness. Exercise training has been recognized as a valuable component in the management of asthma, enhancing lung function and overall well-being. Bicycle ergometer training and Nordic walking are two distinct forms of exercise that have been shown to improve cardiovascular fitness and respiratory function. Despite the potential benefits of these exercises, limited research directly compares their efficacy in improving functional capacity specifically in asthma patients. The study thus aims to address this gap by providing personalized, tailored exercise programs for asthma patients. Methods A single-blinded experimental study using a simple random sampling method was conducted. A sample of 40 subjects was recruited for the study based on inclusion and exclusion criteria and were assigned into two groups. Group A subjects were trained with a bicycle ergometer and Group B subjects were trained with Nordic walking. The intervention was given to both groups for 12 weeks. The outcome measures used were the six-minute walk test, Modified Borg Scale, and Mini Asthma Quality of Life Questionnaire. Results A baseline analysis of outcome measures was done, which was followed up by a post-test analysis after 12 weeks. Pre-test and post-test data were compared using a paired t-test. Intergroup analysis was done by an independent t-test. Both groups showed significant improvement in post-test results. On comparing the two groups, Group A showed significant improvement as compared to Group B. Conclusion The study concludes that bicycle ergometer training is effective in improving functional capacity and enhancing the quality of life in asthma patients.

Reference Values of Cardiopulmonary Exercise Test Parameters in the Contemporary Paediatric Population

BACKGROUND

The evaluation of health status by cardiopulmonary exercise test (CPET) has shown increasing interest in the paediatric population. Our group recently established reference Z-score values for paediatric cycle ergometer VO_2max, applicable to normal and extreme weights, from a cohort of 1141 healthy children. There are currently no validated reference values for the other CPET parameters in the paediatric population. This study aimed to establish, from the same cohort, reference Z-score values for the main paediatric cycle ergometer CPET parameters, apart from VO_2max.

RESULTS

In this cross-sectional study, 909 healthy children aged 5-18 years old underwent a CPET. Linear, quadratic, and polynomial mathematical regression equations were applied to identify the best CPET parameters Z-scores, according to anthropometric parameters (sex, age, height, weight, and BMI). This study provided Z-scores for maximal CPET parameters (heart rate, respiratory exchange ratio, workload, and oxygen pulse), submaximal CPET parameters (ventilatory anaerobic threshold, VE/VCO₂ slope, and oxygen uptake efficiency slope), and maximum ventilatory CPET parameters (tidal volume, respiratory rate, breathing reserve, and ventilatory equivalent for CO₂ and O₂).

CONCLUSIONS

This study defined paediatric reference Z-score values for the main cycle ergometer CPET parameters, in addition to the existing reference values for VO_2max, applicable to children of normal and extreme weights. Providing Z-scores for CPET parameters in the paediatric population should be useful in the follow-up of children with various chronic diseases. Thus, new paediatric research fields are opening up, such as prognostic studies and clinical trials using cardiopulmonary fitness outcomes. Trial registration NCT04876209-Registered 6 May 2021-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04876209 .

Cardiopulmonary fitness in children with asthma versus healthy children

OBJECTIVES

To evaluate, with a cardiopulmonary exercise test (CPET), the cardiopulmonary fitness of children with asthma, in comparison to healthy controls, and to identify the clinical and CPET parameters associated with the maximum oxygen uptake (VO_2max) in childhood asthma.

DESIGN

This cross-sectional controlled study was carried out in CPET laboratories from two tertiary care paediatric centres. The predictors of VO_2max were determined using a multivariable analysis.

RESULTS

A total of 446 children (144 in the asthma group and 302 healthy subjects) underwent a complete CPET. Mean VO_2max was significantly lower in children with asthma than in controls (38.6±8.6 vs 43.5±7.5 mL/kg/min; absolute difference (abs. diff.) of -4.9 mL/kg/min; 95% CI of (-6.5 to -3.3) mL/kg/min; p<0.01) and represented 94%±9% and 107%±17% of predicted values, respectively (abs. diff. -13%; 95% CI (-17 to -9)%; p<0.01). The proportion of children with an impaired VO_2max was four times higher in the asthma group (24% vs 6%, p<0.01). Impaired ventilatory efficiency with increased VE/VCO₂ slope and low breathing reserve (BR) were more marked in the asthma group. The proportion of children with a decreased ventilatory anaerobic threshold (VAT), indicative of physical deconditioning, was three times higher in the asthma group (31% vs 11%, p<0.01). Impaired VO_2max was associated with female gender, high body mass index (BMI), FEV1, low VAT and high BR.

CONCLUSION

Cardiopulmonary fitness in children with asthma was moderately but significantly altered compared with healthy children. A decreased VO_2max was associated with female gender, high BMI and the pulmonary function.

TRIAL REGISTRATION NUMBER

NCT04650464.

Exercise Limitation in Children and Adolescents with Mild-to-Moderate Asthma

BACKGROUND

Children with uncontrolled asthma are less tolerant to exercise due to ventilatory limitation, exercise-induced bronchoconstriction (EIB), or physical deconditioning. The contribution of these factors in children with controlled mild-to-moderate asthma is unknown.

OBJECTIVE

To explore the underlying mechanisms of reduced exercise capacity in children with controlled mild-to-moderate asthma.

METHODS

This was a cross-sectional study of 45 children and adolescents (age 8-18 years) with controlled mild-to-moderate asthma (asthma control test score 21-25) and 61 age-matched healthy controls. All participants completed a physical activity questionnaire and performed spirometry and cardiopulmonary exercise testing (CPET; maximal incremental protocol). Spirometric indices and CPET parameters were compared between the two groups. The effect of EIB (FEV₁ decrease >10% post CPET), ventilatory limitation and physical deconditioning on maximum oxygen uptake (O₂peak), was assessed by multivariable linear regression.

RESULTS

62.2% of children with asthma and 29.5% of controls (P = 0.002) were categorized as inactive. Reduced exercise capacity (O₂peak <80%) was noted in 53.3% of asthmatics and 16.4% of controls (P < 0.001). EIB was documented in 11.1% of participants with asthma. Physical deconditioning was noted in 37.8% of children with asthma and in 14.8% of controls (P = 0.013). Physical deconditioning emerged as the only significant determinant of O₂peak, irrespective of asthma diagnosis, body mass index, ventilatory limitation and EIB.

CONCLUSION

Children with controlled mild-to-moderate asthma are less tolerant to strenuous exercise than their healthy peers. The decreased exercise capacity in this population should mainly be attributed to physical deconditioning, while the contribution of ventilatory limitation and EIB is rather small.

Physical Activity: A Missing Link in Asthma Care

Asthma is the commonest respiratory disease and one of unceasingly increasing prevalence and burden. As such, asthma has attracted a major share or scientific interest and clinical attention. With the various clinical and pathophysiological aspects of asthma having been extensively investigated, the important association between asthma and physical activity remains underappreciated and insufficiently explored. Asthma impacts adversely on physical activity. Likewise, poor physical activity may lead to worse asthma outcomes. This concise clinical review presents the current recommendations for physical activity, discusses the available evidence on physical activity in asthma, and examines the causes of low physical activity in adult asthmatic patients. It also reviews the effect of daily physical activity and exercise training on the pathology and clinical outcomes of asthma. Finally, it summarizes the evidence on interventions targeting physical activity in asthma.

The relationship between heart rate and VO2 in moderate-to-severe asthmatics

Objective: The main purpose of this study was to evaluate whether the %HRR-%VO₂R relationship and %HRR-VO_2peak relationship are affected in patients with moderate or severe asthma and whether airway obstruction and aerobic capacity influence these relationships.Methods: A linear regression was calculated using the paired %VO₂R-%HRR and %VO_2peak-%HRR for 93 subjects with asthma. The mean slope and y-intercept were calculated and compared with the line of identity (y-intercept = 0, slope = 1) for all patients and subgroups for the following conditions: low and normal VO_2peak and low and normal FEV₁.Results: The slope and intercepts of %VO₂R-%HRR were similar to the line of identity for all groups (p > 0.05), and the regressions between %HRR and %VO_2peak did not coincide with the line of identity for all groups (p < 0.05). There were no associations between the intercepts of the %HRR-VO_2peak and the %HRR-%VO₂R relationship with the VO_2peak (p > 0.05) or FEV₁ (p > 0.05).Conclusions: This is the first study to confirm a constant equivalence between %HRR and %VO₂R in outpatients with moderate or severe asthma. Our data also suggest that the relationship between %HRR and %VO_2peak is unreliable. These results support the use of %HRR in relation to %VO₂R to estimate exercise intensity in this population, independently of the pulmonary function and fitness level.

Winter Exercise Reduces Allergic Airway Inflammation: A Randomized Controlled Study

Background: Physical exercise is often recommended as additional treatment for people suffering from allergic rhinitis and/or asthma, but less is known about the specific effects of recreational winter outdoor exercise on allergic airway inflammation. Methods: We performed a longitudinal, randomized controlled intervention study to investigate the effects of recreational winter exercise on allergic airway inflammation, quality of life, spirometry and cardiorespiratory fitness in adults suffering from allergic rhinitis and/or asthma. The exercise group participated in a ten-day winter sports program. The control group did not receive any intervention. Results: A significant improvement of fractional oral exhaled nitric oxide (FeNO; p = 0.008, day 10) and a significant decrease in FeNO after a single 4 h hiking tour (p < 0.001, time effect) were observed for the exercise group. The nasal eosinophilic cell count revealed a short-term reduction (p = 0.021, treatment effect) in the exercise group and for the visual analogue scale sustainable improvements in allergic symptoms (p < 0.001, day 60) were found. No adverse effects of outdoor winter exercise were observed. Conclusion: Recreational winter exercise at moderately cold temperatures reduces allergic airway inflammation measured as FeNO, nasal eosinophilic cell count and induces sustainable improvements in allergic symptoms.

Impact of a Search Engine on Clinical Decisions Under Time and System Effectiveness Constraints: Research Protocol

BACKGROUND

Many clinical questions arise during patient encounters that clinicians are unable to answer. An evidence-based medicine approach expects that clinicians will seek and apply the best available evidence to answer clinical questions. One commonly used source of such evidence is scientific literature, such as that available through MEDLINE and PubMed. Clinicians report that 2 key reasons why they do not use search systems to answer questions is that it takes too much time and that they do not expect to find a definitive answer. So, the question remains about how effectively scientific literature search systems support time-pressured clinicians in making better clinical decisions. The results of this study are important because they can help clinicians and health care organizations to better assess their needs with respect to clinical decision support (CDS) systems and evidence sources. The results and data captured will contribute a significant data collection to inform the design of future CDS systems to better meet the needs of time-pressured, practicing clinicians.

OBJECTIVE

The purpose of this study is to understand the impact of using a scientific medical literature search system on clinical decision making. Furthermore, to understand the impact of realistic time pressures on clinicians, we vary the search time available to find clinical answers. Finally, we assess the impact of improvements in search system effectiveness on the same clinical decisions.

METHODS

In this study, 96 practicing clinicians and final year medical students are presented with 16 clinical questions which they must answer without access to any external resource. The same questions are then represented to the clinicians; however, in this part of the study, the clinicians can use a scientific literature search engine to find evidence to support their answers. The time pressures of practicing clinicians are simulated by limiting answer time to one of 3, 6, or 9 min per question. The correct answer rate is reported both before and after search to assess the impact of the search system and the time constraint. In addition, 2 search systems that use the same user interface, but which vary widely in their search effectiveness, are employed so that the impact of changes in search system effectiveness on clinical decision making can also be assessed.

RESULTS

Recruiting began for the study in June 2018. As of the April 4, 2019, there were 69 participants enrolled. The study is expected to close by May 30, 2019, with results to be published in July.

CONCLUSIONS

All data collected in this study will be made available at the University of Queensland's UQ eSpace public data repository.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/12803.

Association between quality of life, severity of asthma, sleep disorders and exercise capacity in children with asthma: a cross-sectional study

OBJECTIVE

To assess the association between quality of life, asthma severity, sleep disorders and exercise capacity in children with asthma.

METHODS

We evaluated 45 children with asthma of both sexes aged between 7 and 12 years, diagnosed by a pediatrician/pulmonologist and classified according to the IV Brazilian Guidelines for Asthma Management: severity (intermittent/mild and moderate/severe) and control (controlled, partially controlled and uncontrolled). Quality of life (QoL), presence of sleep disorders and exercise capacity were respectively assessed using the following instruments: Pediatric Asthma Quality of Life Questionnaire (PAQLQ); Sleep Disturbance Scale for Children (SDSC); and six-minute step test (6MST).

RESULTS

Intermittent/mild and moderate/severe asthma were observed in 51.1% and 48.9% of the children evaluated, respectively. Only 8.89% of the sample had uncontrolled asthma. In the regression model, a better QoL was observed in children with lower asthma severity, lower SDSC total score and lower levels of dyspnea induced by the 6MST (β=-0.395, p=0.003; β=-0.338, p=0.011; β=-0.352, p=0.008; respectively). These factors explained 31% of the PAQLQ total score variation. Other variables (such as cardiorespiratory variables, spirometry, asthma control and number of steps in 6MST) did not predict quality of life.

CONCLUSIONS

Lower asthma severity (intermittent/mild), fewer symptoms of sleep disorder, and lower exercise-induced dyspnea predicts better quality of life in children with asthma.

Relationship between the sensation of activity limitation and the results of functional assessment in asthma patients

OBJECTIVE

In asthma patients, the assessment of activity limitation is based on questions evaluating how limited the patient feels in their activities. However, the lack of functional data complicates the interpretation of the answers. We aimed to evaluate the intensity of relationships between the patient's perception of activity limitation and the results of several functional tests.

METHODS

Twenty patients complaining of asthma exacerbation were invited to complete three scores (Chronic Respiratory Disease questionnaire, Asthma Control Questionnaire, Hospital Anxiety and Depression scale). They also underwent lung function measurements, a 6-minute walk test and a cardio-pulmonary exercise test. In addition, physical activity was studied by actigraphy. Spearman's rank correlation coefficients between the patient's perception of activity limitation and each of the other parameters were analysed.

RESULTS

Five parameters were significantly correlated with the perception of activity limitation: ACQ question 4, related to dyspnea (rs 0.74, p < 0.001); Emotion domain of the Chronic Respiratory Disease questionnaire (rs -0.57, p = 0.02); HAD anxiety (rs 0.48, p = 0.032); HAD depression (rs 0.46, p = 0.041); ACQ question 6, related to reliever use (rs 0.46, p = 0.046). No parameters from the lung function test, 6MWT, CPET or actigraphy, were significantly correlated with the perception of activity limitation.

CONCLUSIONS

In response to questions about limitation of activity, patients do not specifically answer mentioning physical limitation but rather the psychological burden associated with this constraint.

Exercise as medicine - evidence for prescribing exercise as therapy in 26 different chronic diseases

This review provides the reader with the up-to-date evidence-based basis for prescribing exercise as medicine in the treatment of 26 different diseases: psychiatric diseases (depression, anxiety, stress, schizophrenia); neurological diseases (dementia, Parkinson's disease, multiple sclerosis); metabolic diseases (obesity, hyperlipidemia, metabolic syndrome, polycystic ovarian syndrome, type 2 diabetes, type 1 diabetes); cardiovascular diseases (hypertension, coronary heart disease, heart failure, cerebral apoplexy, and claudication intermittent); pulmonary diseases (chronic obstructive pulmonary disease, asthma, cystic fibrosis); musculo-skeletal disorders (osteoarthritis, osteoporosis, back pain, rheumatoid arthritis); and cancer. The effect of exercise therapy on disease pathogenesis and symptoms are given and the possible mechanisms of action are discussed. We have interpreted the scientific literature and for each disease, we provide the reader with our best advice regarding the optimal type and dose for prescription of exercise.

Activity limitation and exertional dyspnea in adult asthmatic patients: What do we know?

Limitation of activity is the most cited symptom described by uncontrolled asthma patients. Assessment of activity limitation can be undertaken through several ways, more or less complex, subjective or objective. Yet little is known about the link between patients sensations and objective measurements. The present review reports the current knowledge regarding activity limitation and symptom perception (i.e., exertional dyspnea) in adult patients with asthma. This work is based on references indexed by PubMed, irrespective of the year of publication. Overall, patients with stable asthma do not have a more sedentary lifestyle than healthy subjects. However, during a cycle ergometric test, the maximal load is reduced when FEV1, FVC and muscle strengths are decreased. Additionally, during the six-minute walking test, mild asthma patients walk less than healthy subjects even if the minimal clinically important difference is not reached. The major complaint of asthma patients when exercising is dyspnea that is mainly related to the inspiratory effort and also to dynamic hyperinflation in some circumstances. Finally, the administration of bronchodilator does not improve the ventilatory pattern and the exercise capacity of asthma patients and little is known on its effect on exertional dyspnea. The present review allows to conclude that until now there is no gold standard test allowing the objective assessment of "activity limitation and exertional dyspnea" in asthma patients.

High levels of physical activity are associated with poorer asthma control in young females but not in males

BACKGROUND AND OBJECTIVE

Earlier studies on the levels of physical activity in asthma patients compared with controls have yielded varying results. We have previously reported that high versus moderate levels of physical activity were associated with higher prevalence of wheezing, especially in females. Here we studied the levels of physical activity in young patients with asthma and healthy subjects and their effect on asthma control.

METHODS

Four hundred eight physician-diagnosed patients with asthma and 118 controls (10-34 years) answered questions concerning frequency and/or duration of physical activity and undertook the Asthma Control Test (ACT), spirometry, methacholine challenges and exhaled nitric oxide measurements.

RESULTS

Asthma patients were more frequently physically active (P = 0.01) and for longer durations (P = 0.002) than controls. Highly versus moderately physically active patients with asthma had a higher prevalence of not well-controlled asthma (ACT < 20) when physical activity was assessed by frequency (40.6% vs 24.1%, P = 0.001) or duration (39.0% vs 21.7%, P < 0.001). This was only seen in females who had reduced ACT items (P < 0.05). Frequently versus moderately active females had an odds ratio of 4.81 (2.43, 9.51) to have ACT < 20, while no such effect was found in males (OR 1.18 (0.61, 2.30)) and this interaction was statistically significantly associated with gender (P = 0.003). No differences in fraction of exhaled nitric oxide or methacholine reactivity were found between moderately and highly physically active females with asthma.

CONCLUSION

Young asthma patients were more active than controls. High levels of physical activity were associated with poor asthma control as judged by the ACT in females, but not in males, and this appears unrelated to airway inflammation or responsiveness.

Active Video Game Exercise Training Improves the Clinical Control of Asthma in Children: Randomized Controlled Trial

OBJECTIVE

The aim of the present study was to determine whether aerobic exercise involving an active video game system improved asthma control, airway inflammation and exercise capacity in children with moderate to severe asthma.

DESIGN

A randomized, controlled, single-blinded clinical trial was carried out. Thirty-six children with moderate to severe asthma were randomly allocated to either a video game group (VGG; N = 20) or a treadmill group (TG; n = 16). Both groups completed an eight-week supervised program with two weekly 40-minute sessions. Pre-training and post-training evaluations involved the Asthma Control Questionnaire, exhaled nitric oxide levels (FeNO), maximum exercise testing (Bruce protocol) and lung function.

RESULTS

No differences between the VGG and TG were found at the baseline. Improvements occurred in both groups with regard to asthma control and exercise capacity. Moreover, a significant reduction in FeNO was found in the VGG (p < 0.05). Although the mean energy expenditure at rest and during exercise training was similar for both groups, the maximum energy expenditure was higher in the VGG.

CONCLUSION

The present findings strongly suggest that aerobic training promoted by an active video game had a positive impact on children with asthma in terms of clinical control, improvement in their exercise capacity and a reduction in pulmonary inflammation.

TRIAL REGISTRATION

Clinicaltrials.gov NCT01438294.

Cardiorespiratory and sensory responses to exercise in well-controlled asthmatics

OBJECTIVES

The purpose of this study was to evaluate detailed ventilatory, cardiovascular and sensory responses to cycle exercise in sedentary patients with well-controlled asthma and healthy controls.

METHODS

Subjects included sedentary patients meeting criteria for well-controlled asthma (n = 14), and healthy age- and activity-matched controls (n = 14). Visit 1 included screening for eligibility, medical history, anthropometrics, physical activity assessment, and pre- and post-bronchodilator spirometry. Visit 2 included spirometry and a symptom limited incremental cycle exercise test. Detailed ventilatory, cardiovascular and sensory responses were measured at rest and throughout exercise.

RESULTS

Asthmatics and controls were well matched for age, body mass index and physical activity levels. Baseline forced expiratory volume in 1 second (FEV(1)) was similar between asthmatics and controls (98 ± 10 versus 95 ± 9% predicted, respectively, p > 0.05). No significant differences were observed between asthmatics and controls for maximal oxygen uptake (31.8 ± 5.6 versus 30.6 ± 5.9 ml/kg/min, respectively, p > 0.05) and power output (134 ± 35 versus 144 ± 32 W, respectively, p > 0.05). Minute ventilation (V(E)) relative to maximum voluntary ventilation (V(E)/MVV) was similar between groups at maximal exercise with no subjects showing evidence of ventilatory limitation. Asthmatics and controls achieved similar age-predicted maximum heart rates (92 ± 7 versus 93 ± 8% predicted, respectively, p > 0.05). Ratings of perceived breathing discomfort and leg fatigue were not different between groups throughout exercise.

CONCLUSIONS

The results of this study indicate that sedentary patients with well-controlled asthma have preserved sensory and cardiorespiratory responses to exercise with no evidence of exercise impairment or ventilatory limitation.

A 12-month, moderate-intensity exercise training program improves fitness and quality of life in adults with asthma: a controlled trial

Background

Physical training has been shown to improve exercise capabilities in patients with asthma. Most studies focused on children and younger adults. Previously, the maximum program duration was six months. It is not known whether the same results may be obtained with lower intensity programs and sustained for time periods longer than 6 months. This controlled study was undertaken to investigate the effects of a moderate intensity outpatient training program of one year duration on physical fitness and quality of life in adults with asthma.

Methods

21 adult asthmatics (mean age 56 ± 10 years) were allocated to outpatient training (n = 13) or standard care (n = 8). Exercise consisted of once weekly, 60-minute sessions of moderate intensity. Assessments at baseline and after one year included cardiopulmonary exercise testing and Short Form-36 and Asthma Quality of Life Questionnaires.

Results

Following one year of exercise, relevant improvements were observed in the training group for maximum work capacity (p = 0.005), peak oxygen uptake (p < 0.005), O₂pulse (p < 0.05), maximum ventilation (p < 0.005), and most of the quality of life domains. No changes were observed in the control group.

Conclusions

A physiotherapist-led, long-term, moderate-intensity exercise program of one year duration can induce clinically relevant improvements in exercise capabilities and health-related quality of life in well-motivated adults with asthma.

Trial registration

clinicaltrials.gov NCT01097473. Date trial registered: 31.03.2010.

Functional capacity after pediatric liver transplantation: a pilot study

The prospective cross-sectional study investigated the 6MWT performance in pediatric group of liver transplant recipients (6-17 yr, median post-transplantation time of 22 months) and compared to the normal values obtained in healthy children as well as evaluated the reproducibility of the 6MWT. We analyzed the relationship between walked distance and the 6MWw, distance walked × body weight) with the anthropometric, clinical, and pulmonary functions. In post-transplanted group, the average walked distance was significantly shorter compared with control (687 ± 80 m vs. 511 ± 72 m, p < 0.001). The calculated ICC coefficient confirmed the reproducibility among tests. The Pearson correlation revealed that only walked distance in the 6MWT was moderately correlated with tidal volume. Conversely, the 6MWw was significantly correlated with age, weight, height, BMI, FVC, PEF rate, and volume expiratory. According to multiple regression analysis, age, VE and FVC factors explained 80% of the variance in the 6MWw. In conclusion, the pediatric liver transplant recipients' performance in the 6MWT is significantly lower than the values for healthy children of the same age. Notably, the 6MWw may provide relevant information, constituting an additional parameter in the determination of functional capacity.

Pulmonary rehabilitation for respiratory disorders other than chronic obstructive pulmonary disease

Pulmonary rehabilitation (PR) is an important therapeutic intervention that should no longer be considered suitable only for patients with chronic obstructive pulmonary disease (COPD). A strong rationale exists for providing PR to persons with a broad range of respiratory disorders other than COPD. Evidence shows that PR for these patients is feasible, safe and effective. A disease-relevant approach should be undertaken, based on individual patients' needs. Further research is needed to better understand the optimal program content, duration and outcomes measures, to enable diverse patients to achieve maximal benefits of PR.

An official American Thoracic Society/European Respiratory Society statement: key concepts and advances in pulmonary rehabilitation

BACKGROUND

Pulmonary rehabilitation is recognized as a core component of the management of individuals with chronic respiratory disease. Since the 2006 American Thoracic Society (ATS)/European Respiratory Society (ERS) Statement on Pulmonary Rehabilitation, there has been considerable growth in our knowledge of its efficacy and scope.

PURPOSE

The purpose of this Statement is to update the 2006 document, including a new definition of pulmonary rehabilitation and highlighting key concepts and major advances in the field.

METHODS

A multidisciplinary committee of experts representing the ATS Pulmonary Rehabilitation Assembly and the ERS Scientific Group 01.02, "Rehabilitation and Chronic Care," determined the overall scope of this update through group consensus. Focused literature reviews in key topic areas were conducted by committee members with relevant clinical and scientific expertise. The final content of this Statement was agreed on by all members.

RESULTS

An updated definition of pulmonary rehabilitation is proposed. New data are presented on the science and application of pulmonary rehabilitation, including its effectiveness in acutely ill individuals with chronic obstructive pulmonary disease, and in individuals with other chronic respiratory diseases. The important role of pulmonary rehabilitation in chronic disease management is highlighted. In addition, the role of health behavior change in optimizing and maintaining benefits is discussed.

CONCLUSIONS

The considerable growth in the science and application of pulmonary rehabilitation since 2006 adds further support for its efficacy in a wide range of individuals with chronic respiratory disease.

Relationship between exercise capacity and quality of life in adolescents with asthma

OBJECTIVE:

To determine whether the quality of life of adolescents with asthma correlates with parameters obtained prior to and after the six-minute step test (6MST); spirometric results after the 6MST; and level of physical activity.

METHODS:

Nineteen adolescents with asthma, ranging from 11-15 years of age, were assessed with spirometry, 6MST, the International Physical Activity Questionnaire (IPAQ), the Pediatric Asthma Quality of Life Questionnaire (PAQLQ), and the 10-point Borg category-ratio scale.

RESULTS:

Sensation of dyspnea correlated negatively with the total PAQLQ score (r = −0.54) and with the scores of its activity limitation (AL) and symptoms domains (r = −0.64 and r = −0.63, respectively), leg fatigue also correlating negatively with those same domains (r = −0.49 and r = −0.56, respectively). The total IPAQ score correlated with the total PAQLQ score (r = 0.47) and with the PAQLQ AL domain (r = 0.51); IPAQ time spent walking correlated with the PAQLQ symptoms domain (r = 0.45); and IPAQ time spent in vigorous activity correlated with the AL domain (r = 0.50). In the regression analysis, only sensation of dyspnea remained significantly correlated with the total PAQLQ score and the PAQLQ AL domain; leg fatigue remained significantly correlated with the symptoms domain.

CONCLUSIONS:

Higher levels of physical activity indicate better quality of life, as do lower perception of dyspnea and less leg fatigue. The 6MST proved to be a viable option for evaluating exercise capacity in adolescents with asthma, because it reflects the discomfort that asthma causes during activities of daily living.

Physical training for asthma

BACKGROUND

People with asthma may show less tolerance to exercise due to worsening asthma symptoms during exercise or other reasons such as deconditioning as a consequence of inactivity. Some may restrict activities as per medical advice or family influence and this might result in reduced physical fitness. Physical training programs aim to improve physical fitness, neuromuscular coordination and self confidence. Subjectively, many people with asthma report that they are symptomatically better when fit, but results from trials have varied and have been difficult to compare because of different designs and training protocols. Also, as exercise can induce asthma, the safety of exercise programmes needs to be considered.

OBJECTIVES

To gain a better understanding of the effect of physical training on the respiratory and general health of people with asthma, from randomised trials.

SEARCH METHODS

We searched the Cochrane Airways Group Specialised Register of trials up to January 2013.

SELECTION CRITERIA

We included randomised trials of people over eight years of age with asthma who were randomised to undertake physical training or not. Physical training had to be undertaken for at least 20 minutes, two times a week, over a minimum period of four weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility for inclusion and undertook risk of bias assessment for the included studies.

MAIN RESULTS

Twenty-one studies (772 participants) were included in this review with two additional 2012 studies identified as 'awaiting classification'. Physical training was well tolerated with no adverse effects reported. None of the studies mentioned worsening of asthma symptoms following physical training. Physical training showed marked improvement in cardiopulmonary fitness as measured by a statistically and clinically significant increase in maximum oxygen uptake (mean difference (MD) 4.92 mL/kg/min; 95% confidence interval (CI) 3.98 to 5.87; P < 0.00001; 8 studies on 267 participants); however, no statistically significant effects were observed for forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), minute ventilation at maximal exercise (VEmax) or peak expiratory flow rate (PEFR). Meta-analysis of four studies detected a statistically significant increase in maximum heart rate, and following a sensitivity analysis and removal of two studies significance was maintained (MD 3.67 bpm; 95% CI 0.90 to 3.44; P = 0.01). Although there were insufficient data to pool results due to diverse reporting tools, there was some evidence to suggest that physical training may have positive effects on health-related quality of life, with four of five studies producing a statistically and clinically significant benefit.

AUTHORS' CONCLUSIONS

This review demonstrated that physical training showed significant improvement in maximum oxygen uptake, though no effects were observed in other measures of pulmonary function. Physical training was well tolerated among people with asthma in the included studies and, as such, people with stable asthma should be encouraged to participate in regular exercise training, without fear of symptom exacerbation. More research is needed to understand the mechanisms by which physical activity impacts asthma management.

Asthma and physical activity--a population based study results from the Swedish GA(2)LEN survey

BACKGROUND

Having asthma has in previous reports been related to a lower physical activity level. At the same time the prevalence of asthma among elite athletes is high. The aim of this study was to investigate the association between physical activity level and asthma.

METHODS

A postal questionnaire was completed by 25,610 individuals in Sweden. Current asthma was defined as having had an asthma attack during the last 12 months or current use of asthma medication. The participants were asked how often and for how many hours a week they were physically active.

RESULTS

In the population 1830 subjects (7.1%) had current asthma. There was no significant difference in the proportion of subjects that reported being inactive or slightly physically active between asthmatic and non-asthmatics (57 vs. 58%) while the proportion of subjects that were vigorously physically active (≥2 times a week and ≥7 h per week) was higher among the subjects with asthma (6.7 vs. 4.8%, p < 0.0001). Being vigorously physically active was independently related to current asthma (OR (95% CI)) 1.40 (1.11-1.77)), wheeze (1.39 (1.17-1.65)), wheeze and breathlessness (1.68 (1.38-2.04)), and wheezing without having a cold (1.39 (1.13-1.71)). The association between being vigorously physically active and wheeze was significantly stronger in women compared to men.

CONCLUSIONS

There was no difference in the proportion of subjects with a reported low level of physical activity between asthmatics and non-asthmatics. Health care professionals should, however, be aware of the increased prevalence of asthma and asthma-related symptoms in vigorously physically active subjects.

Children and adolescents with mild intermittent or mild persistent asthma: aerobic capacity between attacks

OBJECTIVE

To assess children and adolescents diagnosed with mild intermittent or mild persistent asthma, in terms of their aerobic capacity between attacks.

METHODS

We included 33 children and adolescents recently diagnosed with asthma (mild intermittent or mild persistent) and 36 healthy children and adolescents. Those with asthma were evaluated between attacks. All participants underwent clinical evaluation; assessment of baseline physical activity level; pre- and post-bronchodilator spirometry; and a maximal exercise test, including determination of maximal voluntary ventilation, maximal oxygen uptake, respiratory quotient, maximal minute ventilation, ventilatory equivalent, ventilatory reserve, maximal HR, SpO2, and serum lactate.

RESULTS

No significant differences were found among the groups (intermittent asthma, persistent asthma, and control) regarding anthropometric or spirometric variables. There were no significant differences among the groups regarding the variables studied during the maximal exercise test.

CONCLUSIONS

A diagnosis of mild intermittent/persistent asthma has no effect on the aerobic capacity of children and adolescents between asthma attacks.

Swimming training for asthma in children and adolescents aged 18 years and under

BACKGROUND

Asthma is the most common chronic medical condition in children and a common reason for hospitalisation. Observational studies have suggested that swimming, in particular, is an ideal form of physical activity to improve fitness and decrease the burden of disease in asthma.

OBJECTIVES

To determine the effectiveness and safety of swimming training as an intervention for asthma in children and adolescents aged 18 years and under.

SEARCH METHODS

We searched the Cochrane Airways Group's Specialised Register of trials (CENTRAL), MEDLINE , EMBASE, CINAHL, in November 2011, and repeated the search of CENTRAL in July 2012. We also handsearched ongoing Clinical Trials Registers.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) and quasi-RCTs of children and adolescents comparing swimming training with usual care, a non-physical activity, or physical activity other than swimming.

DATA COLLECTION AND ANALYSIS

We used standard methods specified in the Cochrane Handbook for Systematic reviews of Interventions. Two review authors used a standard template to independently assess trials for inclusion and extract data on study characteristics, risk of bias elements and outcomes. We contacted trial authors to request data if not published fully. When required, we calculated correlation coefficients from studies with full outcome data to impute standard deviation of changes from baseline.

MAIN RESULTS

Eight studies involving 262 participants were included in the review. Participants had stable asthma, with severity ranging from mild to severe. All studies were randomised trials, three studies had high withdrawal rates. Participants were between five to 18 years of age, and in seven studies swimming training varied from 30 to 90 minutes, two to three times a week, over six to 12 weeks. The programme in one study gave 30 minutes training six times per week. The comparison was usual care in seven studies and golf in one study. Chlorination status of swimming pool was unknown for four studies. Two studies used non-chlorinated pools, one study used an indoor chlorinated pool and one study used a chlorinated but well-ventilated pool.No statistically significant effects were seen in studies comparing swimming training with usual care or another physical activity for the primary outcomes; quality of life, asthma control, asthma exacerbations or use of corticosteroids for asthma. Swimming training had a clinically meaningful effect on exercise capacity compared with usual care, measured as maximal oxygen consumption during a maximum effort exercise test (VO2 max) (two studies, n = 32), with a mean increase of 9.67 mL/kg/min; 95% confidence interval (CI) 5.84 to 13.51. A difference of equivalent magnitude was found when other measures of exercise capacity were also pooled (four studies, n = 74), giving a standardised mean difference (SMD) 1.34; 95% CI 0.82 to 1.86. Swimming training was associated with small increases in resting lung function parameters of varying statistical significance; mean difference (MD) for FEV1 % predicted 8.07; 95% CI 3.59 to 12.54. In sensitivity analyses, by risk of attrition bias or use of imputed standard deviations, there were no important changes on effect sizes. Unknown chlorination status of pools limited subgroup analyses.Based on limited data, there were no adverse effects on asthma control or occurrence of exacerbations.

AUTHORS' CONCLUSIONS

This review indicates that swimming training is well-tolerated in children and adolescents with stable asthma, and increases lung function (moderate strength evidence) and cardio-pulmonary fitness (high strength evidence). There was no evidence that swimming training caused adverse effects on asthma control in young people 18 years and under with stable asthma of any severity. However whether swimming is better than other forms of physical activity cannot be determined from this review. Further adequately powered trials with longer follow-up periods are needed to better assess the long-term benefits of swimming.

Association between maximal aerobic capacity and psychosocial factors in adults with moderate-to-severe asthma

BACKGROUND

The symptoms of asthma impair health-related quality of life (HRQoL), increase anxiety and depression and may keep subjects from engaging in physical exercise. Physical inactivity has been related to poor asthma outcomes; however, the association between physical fitness and psychosocial disorders remains poorly understood.

OBJECTIVE

To verify the association between aerobic capacity, HRQoL, and psychological distress in adults with moderate or severe persistent asthma who were clinically stable.

METHODS

Eighty-eight participants (68 females) with either moderate or severe persistent asthma (age range, 20-60 years) who were under medical treatment for at least 6 months and considered clinically stable were studied. Participants were evaluated on two non-consecutive days. On the first day, the HRQoL, depression and anxiety levels and pulmonary function were assessed. On the second day, subjects underwent cardiopulmonary exercise testing.

RESULTS

Using the agglomerative cluster approach, two clusters were identified: 21 participants (24%) were grouped in Cluster 1, and 67 (76%) were grouped in Cluster 2. Asthmatic subjects from Cluster 1 exhibited increased aerobic capacity, better HRQoL and lower depression levels than did subjects in Cluster 2 (p < .05). No difference was observed between the clusters with respect to gender, age, body mass index (BMI) or pulmonary function (p > .05). The discriminant function model exhibits good accuracy (R(2) = 0.79) and predicted 93% of the case allocations.

CONCLUSION

Our results suggest an association between reduced exercise capacity, low HRQoL and increases in depressive symptoms in clinically stable asthmatic subjects. These results suggest the need to assess physical fitness and psychosocial distress during asthma treatment and the importance of a multidisciplinary approach.

Analysis of physiological variables during acute hypoxia and maximal stress test in adolescents clinically diagnosed with mild intermittent or mild persistent asthma

OBJECTIVE

To analyze adolescents clinically diagnosed with asthma, in terms of the physiological changes occurring during acute hypoxia and during a maximal stress test.

METHODS

This was a descriptive, cross-sectional study involving 48 adolescents (12-14 years of age) who were divided into three groups: mild intermittent asthma (MIA, n = 12); mild persistent asthma (MPA, n = 12); and control (n = 24). All subjects were induced to acute hypoxia and were submitted to maximal stress testing. Anthropometric data were collected, and functional variables were assessed before and after the maximal stress test. During acute hypoxia, the time to a decrease in SpO2 and the time to recovery of SpO2 (at rest) were determined.

RESULTS

No significant differences were found among the groups regarding the anthropometric variables or regarding the ventilatory variables during the stress test. Significant differences were found in oxygen half-saturation pressure of hemoglobin prior to the test and in PaO2 prior to the test between the MPA and control groups (p = 0.0279 and p = 0.0116, respectively), as was in the oxygen extraction tension prior to the test between the MIA and MPA groups (p = 0.0419). There were no significant differences in terms of the SpO2 times under any of the conditions studied. Oxygen consumption and respiratory efficiency were similar among the groups. The use of a bronchodilator provided no significant benefit during the hypoxia test. No correlations were found between the hypoxia test results and the physiological variables.

CONCLUSIONS

Our findings suggest that adolescents with mild persistent asthma have a greater capacity to adapt to hypoxia than do those with other types of asthma.

Low serum high-density lipoprotein cholesterol in childhood is associated with adolescent asthma

BACKGROUND

Whilst emerging evidence from animal and cell experiments has shown high-density lipoprotein cholesterol to have anti-inflammatory effects consistent with a protective role in asthma, human studies investigating the relationship of high-density lipoprotein cholesterol with asthma have produced conflicting results.

OBJECTIVE

To examine the association between serum lipids among Cypriot children aged 11-12 years and prevalence of asthma at age 15-17 years.

METHODS

In 3982 children, we assessed serum lipids, body mass index and maximal oxygen consumption at baseline (2001-2003) and explored associations with respiratory health at follow-up (2007) using multiple logistic regression models.

RESULTS

Lower levels of high-density lipoprotein cholesterol at age 11-12 years were found in subjects who reported ever asthma (58.2 vs. 60.0 mg/dL, P = 0.005) and active asthma (57.5 vs. 59.9 mg/dL, P = 0.010) in adolescence, in comparison with their respective reference groups. Total cholesterol, low-density lipoprotein and triglycerides had no association with any of the asthma outcomes. In contrast, with estimated odds ratios of 1.89 (95% CI 1.19-3.00) and 1.89 (95% CI 1.02-3.53), ever asthma and active asthma respectively appeared particularly pronounced among those who at baseline had high-density lipoprotein cholesterol <40 mg/dL, even after adjusting for potential confounders including body mass index and maximal oxygen consumption.

CONCLUSIONS & CLINICAL RELEVANCE

Low-serum high-density lipoprotein cholesterol in childhood is associated with an increased risk for asthma in adolescence, suggesting a potential role of this lipoprotein in the pathogenesis of paediatric asthma.

Physical training for asthma

BACKGROUND

People with asthma may show less tolerance to exercise due to worsening asthma symptoms during exercise or other reasons such as deconditioning, as a consequence of inactivity. Some may also restrict activities as per medical advice or family influence and this might result in reduced physical fitness. Physical training programs aim to improve physical fitness, neuromuscular coordination and self confidence. Subjectively, many people with asthma report that they are symptomatically better when fit, but results from trials have varied and have been difficult to compare because of different designs and training protocols. Also, as exercise can induce asthma, the safety of exercise programmes need to be considered.

OBJECTIVES

To gain a better understanding of the effect of physical training on the respiratory and general health of people with asthma, from randomised trials.

SEARCH METHODS

We searched the Cochrane Airways Group Specialised Register of trials up to April 2011.

SELECTION CRITERIA

We included randomised trials of people over eight years of age with asthma who were randomised to undertake physical training. Physical training had to be undertaken for at least twenty minutes, two times a week, over a minimum period of four weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility for inclusion and the quality of trials.

MAIN RESULTS

Nineteen studies (695 participants) were included in this review. Physical training was well tolerated with no adverse effects reported. None of the studies mentioned worsening of asthma symptoms following physical training. Physical training improved cardiopulmonary fitness as measured by a statistically and clinically significant increase in maximum oxygen uptake (MD 5.57 mL/kg/min; 95% confidence interval (CI) 4.36 to 6.78; six studies on 149 participants) and maximum expiratory ventilation (6.0 L/min, 95% CI 1.57 to 10.43; four studies on 111 participants) with no significant effect on resting lung function (performed in four studies). Although there were insufficient data to pool due to diverse reporting tools, there is some evidence available to suggest that physical training may have positive effects on health-related quality of life, with four of five studies producing a statistically and clinically significant benefit.

AUTHORS' CONCLUSIONS

This review demonstrated that physical training can improve cardiopulmonary fitness and was well tolerated among people with asthma in the included studies. As such, people with stable asthma should be encouraged to partake in regular exercise training, without fear of symptom exacerbation.

Exercise-related quality of life in subjects with asthma: a systematic review

OBJECTIVE

The purpose of this review was to analyze, based on a review of the current literature, the effects of physical activity on the quality of life (QoL) of subjects with asthma.

METHODS

The authors conducted a search of randomized controlled trials (RCTs) between January 2000 and August 2010 in a group of major databases of health sciences (Academic Search Complete, Directory of Open Access Journals, Elsevier--Science Direct, Highwire Press, PubMed, Scielo Global, Scirus, Scopus, SpringerLink, Taylor & Francis, and Wiley Interscience) with the keywords asthma, QoL, physical activity, exercise, training, and program in all possible combinations. Citations and references of each study selected were also examined.

RESULTS

Of the 1075 studies identified, only 11 were included. Five of these studies were performed in children between the ages of 7 and 15 and the remaining studies were performed on adults. Intervention programs were divided into aerobic training programs and breathing exercises programs. All aerobic training programs showed improvements in QoL, demonstrating a positive influence of aerobic training on asthma.

CONCLUSIONS

There is a noticeable trend in the benefit of aerobic training programs in the QoL for individuals with asthma. The breathing exercises programs were few and heterogeneous, making it difficult to reach a positive conclusion on whether it could be recommended for the improvement of QoL in this pathology. There is a great need for more RCTs with methodological rigor.

Effects of physical exercise on lung injury and oxidant stress in children with asthma

BACKGROUND

The aim of this study was to investigate the influence of exercise training on oxidative stress and markers of lung inflammation in children with asthma.

METHODS

Thirty children aged 8-13 years diagnosed with asthma were enrolled in the study as well as 13 healthy children. One group received only pharmacological treatment and the other group was also enrolled in an exercise programme. Venous blood and 24-hour urine samples were obtained from the children enrolled in the study at the beginning and end of the study. Leukotriene E4 and creatinine levels were measured in the urine and matrix metallopeptidase (MMP-9), endothelin-1(ET-1), malnodialdehyde (MDA), IgE and specific IgE levels were measured in blood samples.

RESULTS

Leukotriene E4, MDA and MMP9 levels decreased significantly with treatment in both groups (p < 0.001). However, ET-1 levels decreased significant only in the exercise group (26.5 ± 3.6 vs 21.3 ± 2.4 pg/ml respectively, p = 0.001). Moreover, ET-1 levels were found to be significantly lower in the exercise group compared to the only pharmacotherapy group (24.2 ± 3.1 vs 21.3 ± 2.4 pg/ml, p=0.007).

CONCLUSIONS

Positive influences of exercise training in children with asthma may be mediated by decrease in ET-1 levels.

Pulmonary disorders in athletes

Exercise is rarely limited by pulmonary causes in normal individuals. Cardiac output and peripheral muscle disease are usually the limiting factors. Although minute ventilation rises steeply during exercise, normal individuals maintain a substantial breathing reserve. Exercise in patients, however, can be limited by pulmonary disorders. Acute pulmonary causes (exercise-induced bronchospasm, vocal cord dysfunction, exercise-induced anaphylaxis, and exercise-induced urticaria) or chronic disorders (obstructive and restrictive lung disorders) reduce exercise tolerance. Exercise testing has proved the mainstay for diagnosis and treatment of these disorders.

Physical activity participation among adult Nevadans with self-reported asthma

OBJECTIVE

This study looked at physical activity patterns among adults (≥ 18 years old) with self-reported asthma living in Nevada and investigated how physical inactivity is associated with asthma prevalence.

METHODS

We examined data from the 2009 Nevada Behavioral Risk Factor Surveillance System. Different physical activity measures among individuals were compared by asthma status.

RESULTS

Among 3840 respondents, 13.9% and 9.0% of them self-reported lifetime and current asthma, respectively. Significantly higher proportions of people with lifetime (12.9%) and current (17.7%) asthma did not engage in regular physical activity or exercise than those without lifetime (7.0%) and current (6.8%) asthma (p < .01). Over 30% of the respondents with asthma had no leisure-time physical activity compared with about 23% of those without asthma (p < .05). Moreover, these findings were statistically significant after adjusting for body mass index as well as other common sociodemographic variables. It was also found that asthmatic people spent significantly less time on moderate and vigorous physical activity than their nonasthmatic counterparts (223 minutes/week vs. 283 minutes/week for moderate physical activity; 214 minutes/week vs. 281 minutes/week for vigorous physical activity; p < .001). More than half of the respondents with asthma and close to half of those without asthma did not meet the current physical activity recommendation.

CONCLUSION

A majority of adults with self-reported asthma living in Nevada are physically inactive. It appears that physical inactivity is associated with an increased prevalence of asthma.

The beneficial effects of physical exercise on antioxidant status in asthmatic children

BACKGROUND

The pathogenesis of asthma involves both airway inflammation and an oxidant/antioxidant imbalance. It is demonstrated in asthmatic adults that exercise programmes improve lung function, a mechanism yet to be elucidated. The purpose of this study was to investigate the possible beneficial effects of physical exercise on antioxidant status in asthmatic children which may lead to ameliorated lung function.

METHODS

The study enrolled thirteen control and thirty asthmatic children. The asthmatic group was subdivided into two: the first group receiving only pharmacological treatment (n=15) and the second receiving pharmacological treatment with exercise programme (n=15) for 8 weeks. Blood samples were drawn from the subjects before and after treatment periods. As oxidant stress markers blood levels of malondialdehyde (MDA) and total nitric oxide (NO), and as antioxidant status, glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) enzyme activities were assessed.

RESULTS

Before any treatment was initiated, MDA and NO levels in the asthmatic group were significantly higher than the controls (3.40±0.96 nmol/ml vs 2.46±0.58 nmol/ml, and 12.53±2.10 vs 9.40±1.39 micromol/L, respectively). Both SOD (p=0.0001) and GSH-Px (p=0.023) activities were significantly lower in the asthmatic group. Pharmacological treatment and exercise programme together significantly improved lung performance and decreased the levels of oxidant stress markers, in concordance with a significantly increase in antioxidant enzyme activity measures when compared to the pharmacological treatment.

CONCLUSION

Structured exercise programme in asthmatic children resulted in better lung function, which may be attributed to its effect on antioxidant status.

Effects of exercise training on atrophy gene expression in skeletal muscle of mice with chronic allergic lung inflammation

We evaluated the effects of chronic allergic airway inflammation and of treadmill training (12 weeks) of low and moderate intensity on muscle fiber cross-sectional area and mRNA levels of atrogin-1 and MuRF1 in the mouse tibialis anterior muscle. Six 4-month-old male BALB/c mice (28.5 +/- 0.8 g) per group were examined: 1) control, non-sensitized and non-trained (C); 2) ovalbumin sensitized (OA, 20 microg per mouse); 3) non-sensitized and trained at 50% maximum speed _ low intensity (PT50%); 4) non-sensitized and trained at 75% maximum speed _ moderate intensity (PT75%); 5) OA-sensitized and trained at 50% (OA+PT50%), 6) OA-sensitized and trained at 75% (OA+PT75%). There was no difference in muscle fiber cross-sectional area among groups and no difference in atrogin-1 and MuRF1 expression between C and OA groups. All exercised groups showed significantly decreased expression of atrogin-1 compared to C (1.01 +/- 0.2-fold): PT50% = 0.71 +/- 0.12-fold; OA+PT50% = 0.74 +/- 0.03-fold; PT75% = 0.71 +/- 0.09-fold; OA+PT75% = 0.74 +/- 0.09-fold. Similarly significant results were obtained regarding MuRF1 gene expression compared to C (1.01 +/- 0.23-fold): PT50% = 0.53 +/- 0.20-fold; OA+PT50% = 0.55 +/- 0.11-fold; PT75% = 0.35 +/- 0.15-fold; OA+PT75% = 0.37 +/- 0.08-fold. A short period of OA did not induce skeletal muscle atrophy in the mouse tibialis anterior muscle and aerobic training at low and moderate intensity negatively regulates the atrophy pathway in skeletal muscle of healthy mice or mice with allergic lung inflammation.

Moderate and vigorous exercise programs in children with asthma: safety, parental satisfaction, and asthma outcomes

BACKGROUND

Previous research suggests that physical activity programs may improve fitness and reduce symptoms in children with asthma, but few studies have included severe asthmatics and focused on safety and parental satisfaction with the programs.

OBJECTIVE

To examine safety, parental satisfaction, and pre- to post-intervention changes in symptoms and quality of life (QOL) in a pilot study of the impact of vigorous physical activity (swimming) and moderate-intensity activity (golf) on inner-city children with asthma.

DESIGN/METHODS

Children with asthma (7-14 years old) residing in Milwaukee's highest asthma prevalence zip codes were randomized to a 9-week swimming or golf program. Pre- and post-intervention data were obtained on safety, parental satisfaction, asthma symptoms, quality of life, and urgent asthma physician visits.

RESULTS

Twenty-eight children in the swimming group and 17 in the golf group completed the program. Combined group analysis (N = 45) revealed that only six symptom exacerbations occurred during 1,125 person-sessions of swimming and golf (all resolved with bronchodilator therapy), 92% of parents were very or extremely satisfied with the program, and post-exercise decreases were observed in asthma symptom severity scores (9.3-7.3, P < 0.001), improved parental QOL (4.9-5.4, P < 0.001), and reduced urgent physician visits for asthma (1.3-0.2 visits per person, P = 0.04). The study lacked sufficient power to perform intergroup comparisons.

CONCLUSIONS

Findings from this pilot study indicate that vigorous (swimming) and moderate-intensity (golf) physical activity programs are well-tolerated, safe, and achieve high parental satisfaction. Participants and parents reported reduced childhood asthma symptoms and physician office visits and improved parental QOL. These findings suggest a potentially beneficial role for moderate to vigorous physical activity in childhood asthma.

Exercise training on disease control and quality of life in asthmatic children

PURPOSE

Aerobic training has been shown to be effective in improving cardiopulmonary fitness in asthmatic children. However, the actual impact of physical training on clinical indicators of disease control remains controversial.

METHODS

Thirty-eight children with moderate to severe persistent asthma were randomly assigned to control (N=17) and training (N=21) groups. Spirometry, exercise challenge, and maximum incremental cardiopulmonary exercise tests were performed 16 wk apart. Daily doses of inhaled steroids and Pediatric Asthma Quality of Life Questionnaire (PAQLQ) scores were also recorded.

RESULTS

Physical training was associated with significant improvements in physiological variables at peak and submaximal exercise (P<0.05); in contrast, no significant changes were found in controls. Severity of exercise-induced bronchoconstriction (EIB) and postexercise breathlessness were significantly lessened in trained patients; improvement in fitness and EIB, however, were not linearly related (P>0.05). In addition, PAQLQ scores improved only in trained children (P<0.01). Daily doses of inhaled steroids were reduced in trained patients (52%), but they remained unchanged or increased in controls (70.6%) (P=0.07).

CONCLUSION

Supervised exercise training might be associated with beneficial effects on disease control and quality of life in asthmatic children. These data suggest an adjunct role of physical conditioning on clinical management of patients with more advanced disease.

Cardiopulmonary responses of asthmatic children to exercise: analysis of systolic and diastolic cardiac function

The aim of this study was to evaluate aerobic exercise capacity, cardiac features and function in a group of asthmatic children who underwent medical treatment. Dynamic exercise testing was done to evaluate aerobic exercise capacity. Echocardiography was performed to identify the effects that asthma-induced pulmonary changes have on respiratory and cardiac function in these patients. The study involved 20 asthmatic children (aged 7-16 years) who were followed at our hospital and 20 age- and sex-matched, healthy control subjects. Sixteen of the asthma cases were moderate and four were severe. All 40 subjects underwent similar series of assessments: multiple modes of echocardiography, treadmill stress testing, pulmonary function testing. The means for forced expiratory volume in 1 sec, forced expiratory flow 25-75%, maximal voluntary ventilation and inspiratory capacity were all significantly higher in the control group. The patient group had significantly lower mean maximal oxygen uptake and mean endurance time than the controls but there were no significant differences between the groups with respect to respiratory exchange ratio or the ventilatory threshold. The control group means for ejection fraction, fractional shortening, left ventricular mass, and left ventricular mass index were significantly higher than the corresponding patient group results. Children with moderate or severe asthma have lower aerobic capacity than healthy children of the same age. The data suggest that most of these children have normal diastolic cardiac function, but exhibit impaired systolic function and have lower LVM than healthy peers of the same age.

Evidence for prescribing exercise as therapy in chronic disease

Considerable knowledge has accumulated in recent decades concerning the significance of physical activity in the treatment of a number of diseases, including diseases that do not primarily manifest as disorders of the locomotive apparatus. In this review we present the evidence for prescribing exercise therapy in the treatment of metabolic syndrome-related disorders (insulin resistance, type 2 diabetes, dyslipidemia, hypertension, obesity), heart and pulmonary diseases (chronic obstructive pulmonary disease, coronary heart disease, chronic heart failure, intermittent claudication), muscle, bone and joint diseases (osteoarthritis, rheumatoid arthritis, osteoporosis, fibromyalgia, chronic fatigue syndrome) and cancer, depression, asthma and type 1 diabetes. For each disease, we review the effect of exercise therapy on disease pathogenesis, on symptoms specific to the diagnosis, on physical fitness or strength and on quality of life. The possible mechanisms of action are briefly examined and the principles for prescribing exercise therapy are discussed, focusing on the type and amount of exercise and possible contraindications.

Physical training for asthma

BACKGROUND

Physical training programmes have been designed for asthmatic subjects with the aim of improving physical fitness, neuromuscular coordination and self-confidence. Habitual physical activity increases physical fitness and lowers ventilation during mild and moderate exercise thereby reducing the likelihood of provoking exercise induced asthma. Exercise training may also reduce the perception of breathlessness through a number of mechanisms including strengthening respiratory muscles. Subjectively, many asthmatics report that they are symptomatically better when fit, but results from trials have varied and have been difficult to compare because of different designs and training protocols.

OBJECTIVES

The purpose of this review was to assess evidence for the efficacy and effectiveness of physical training in asthma.

SEARCH STRATEGY

We searched the Cochrane Airways Group Specialised Register, SportDiscus and the Science Citation Index up to May 2005.

SELECTION CRITERIA

Randomised trials in asthmatic subjects undertaking physical training. Subjects had to be eight years and older. Physical training had to be undertaken for at least 20 to 30 minutes, two to three times a week, over a minimum of four weeks.

DATA COLLECTION AND ANALYSIS

Eligibility for inclusion and quality of trials were assessed independently by two reviewers.

MAIN RESULTS

Thirteen studies (455 participants) were included in this review. Physical training had no effect on resting lung function or the number of days of wheeze. The results of this review have shown that lung function and wheeze is not worsened by physical training in patients with asthma. Physical training improved cardiopulmonary fitness as measured by an increase in maximum oxygen uptake of 5.4 ml/kg/min (95% confidence interval 4.2 to 6.6) and maximum expiratory ventilation 6.0 L/min (95% confidence interval 1.5 to 10.4). There were no data concerning quality of life measurements.

AUTHORS' CONCLUSIONS

In people with asthma, physical training can improve cardiopulmonary fitness without changing lung function. It is not known whether improved fitness is translated into improved quality of life. It is comforting to know that physical training does not have an adverse effect on lung function and wheeze in patients with asthma. Therefore, there is no reason why patients with asthma should not participate in regular physical activity.

Are inhaled corticosteroids associated with an increased risk of fracture in children?

Inhaled corticosteroids are widely used in the long-term management of asthma in children. Data on the relationship between inhaled corticosteroid therapy and osteoporotic fracture are inconsistent. We address this issue in a large population-based cohort of children aged 4-17 years in the UK (the General Practice Research Database). The incidence rates of fracture among children aged 4-17 years taking inhaled corticosteroids (n=97,387), taking bronchodilators only (n=70 984) and a reference group (n=345,758) were estimated. Each child with a non-vertebral fracture (n=23,984) was subsequently matched by age, sex, practice, and calendar time to one child without a fracture. Fracture incidence was increased in children using inhaled corticosteroids, as well as in those receiving bronchodilators alone. With an average daily beclomethasone dose of 200 microg or less, the crude fracture risk relative to nonusers was 1.10 [95% confidence interval (CI), 0.96-1.26]; with dosage of 201-400 microg, it was 1.23 (95% CI, 1.08-1.39); and with dosages over 400 microg, it was 1.36 (95% CI, 1.11-1.67). This excess risk disappeared after adjustment for indicators of asthma severity. The increased risk of fracture associated with use of inhaled corticosteroids is likely to be the result of the underlying illness, rather than being directly attributable to inhaled corticosteroid therapy.

Airways hyperresponsiveness in high school athletes

Adult athletes have a higher prevalence (11%-50%) of exercise-induced bronchoconstriction (EIB) and airways hyperresponsiveness (AHR) than the population at large (7%-11%): reports describing EIB/AHR in adolescent athletes are scant.

HYPOTHESES

1) a minimum AHR prevalence of 20% would be revealed in a group of high school athletes; 2) demographic data would predict AHR; 3) AHR-positive athletes would preferentially choose low ventilation sports. Eucapnic voluntary hyperpnea (EVH) was used to test for AHR in 23% of all athletes (79 of 343) of a midwestern high school. The AHR was defined by at least a 10%, 20%, or 25% decline in FEV1, FEF25-75, or PEFR at 1, 5, 10, or 15-min post-EVH, respectively.

RESULTS

30 of 79 (38%) tested positive for AHR; demographic data tended to predict AHR, as correlations between the total number of years exercised with the greatest decline in FEV1 and the total number of days exercised with the greatest decline in FEV1 following the EVH challenge tended to be significant (r = 0.354; p = 0.055 and r=0.314; p = 0.091, respectively); and 69% of AHR-positive students played only low ventilation sports.

CONCLUSION

AHR prevalence was 38% in athletes of a midwestern high school; demographic data tended to predict AHR; those with AHR preferentially play low ventilation sports.

Quality of life in adolescents with mild asthma

The majority of individuals with asthma have mild disease, often in conjunction with allergic rhinitis and exercise-induced bronchoconstriction (EIB). Although health-related quality-of-life (HRQoL) is reduced in moderate to severe asthma and allergic rhinitis, little is known about the effect of mild asthma, mild allergic rhinitis, and EIB on HRQoL outcomes. The objective of this study was to determine the effect of mild asthma, allergic rhinitis, and EIB on HRQoL. A cross-sectional study was conducted of 160 adolescent athletes participating in a screening program to detect EIB. Generic HRQoL was assessed with the teen version of the pediatric quality-of-life inventory (PedsQL). Prior diagnoses of asthma, allergic rhinitis, and EIB, and current symptoms of dyspnea during exercise and asthma, were recorded. Lung function and the presence of EIB were determined by spirometry before and after an exercise challenge test. Adolescent athletes with a prior physician diagnosis of asthma had a lower HRQoL scale summary score (P<0.01) and lower physical functioning, emotional functioning, and school functioning domain scores (P values, 0.01-0.02) in comparison to adolescent athletes with no prior diagnosis of these disorders. Athletes with a prior diagnosis of asthma reported dyspnea during exercise more frequently than did those without asthma (P<0.001). Adolescent athletes with dyspnea during exercise had a lower scale summary score, and lower physical functioning, general well-being, and emotional functioning domain scores (P values, 0.02-0.03). These data show that mild asthma and dyspnea without asthma significantly affect HRQoL. Symptoms of dyspnea during exercise are common in asthma and are associated with lower HRQoL. The clinical significance of these differences in HRQoL is unclear.