Physical training for asthma

Effect of exposure to disinfection by-products during swimming exercise on asthma-related immune responses

Swimming is a widely practiced exercise in modern society, where there is a heightened interest in health. The exceptional benefits of swimming are well-known, yet the issue of water quality management inevitably arises due to its nature as an aquatic exercise. Several studies reported that chlorine disinfectants commonly used in swimming pool water disinfection could degrade into toxic disinfection by-products (DBPs) and suggested that the DBPs might induce respiratory disorders, including asthma. Conversely, there were also reports that the DBPs had no significant effects on respiratory conditions. In this study, we investigated the influence of swimming exercise and DBPs on asthma. The decomposition products had little effect on the number of T cells in various immune organs. However, swimming exercise was found to increase the cell count in proportion to the exercise duration. Nevertheless, there were no significant changes in other immune cells and the secretion of asthma-related cytokines. These findings indicate that the effects of swimming pool DBPs on respiratory conditions during swimming exercise are either negligible or absent, and instead, the immunological benefits gained through consistent swimming exercise outweigh any potential drawbacks.

The Effect of Threshold Loading Training and an Innovative Respiratory Training Devices with Lower Torso Sports Training in Asthma Patients: A Randomized Trial

This study investigated the influence of two different devices with lower torso sports training in patients with asthma. Patients with asthma (n = 300) aged 55-60 years with FEV1/FVC ratio < 65%, who were repeatedly admitted to a pulmonary rehabilitation centre, participated. Patients were evaluated and randomized into two groups (experimental group 1; EXP-1, n = 150, who applied a conventional threshold loading device, and experimental group 2; EXP-2, n = 150, who used an innovative respiratory training device). Patients were included only if they met the global criteria for asthma. The experimental intervention period lasted 10 weeks with 3 weekly training sessions lasting 30-40 min. The maximal inspiratory pressure (PI, max), pulmonary function test, baseline dyspnoea index (BDI), oxygen saturation, and 6 min walking test (6MWT) performance were all measured at baseline and postintervention. Also, an assessment of the 1 min repeated exercise performance (leg extension and leg press) was performed. Moreover, St. George Respiratory Questionnaire was used to quantify the quality of life (SGRQ). Statistical analysis displayed significant favourable effects on 6MWT, leg press, and FRV1, for patients using both devices (EXP-1 and EXP-2, respectively) with lower torso athletic training. The other variables, weight SPO2 and SGRO, also showed no significant change in neither EXP-1 nor EXP-2. Thus, the new respiratory training device (EXP-2) appeared to be as effective as the conventional threshold loading device (EXP-1). In conclusion, our findings demonstrated beneficial effects of combining respiratory training with athletic training in asthma patients. Additionally, the validity of a unique respiratory training device for asthma patients was confirmed.

Physical training in adults with asthma: An integrative approach on strategies, mechanisms, and benefits

Asthma is a chronic airway disease characterized by airflow limitation and respiratory symptoms associated with chronic airway and systemic inflammation, bronchial hyperreactivity (BHR), and exercise-induced bronchoconstriction (EIB). Asthma is a heterogeneous disease classified according to distinct airway and systemic inflammation. Patients commonly present with several comorbidities, including anxiety, depression, poor sleep quality, and reduced physical activity levels. Individuals with moderate to severe asthma often have more symptoms and difficulty achieving adequate clinical control, which is associated with poor quality of life, despite proper pharmacological treatment. Physical training has been proposed as an adjunctive therapy for asthma. Initially, it was suggested that the effect of physical training might be attributed to the improved oxidative capacity and reduced production of exercise metabolites. However, in the last decade, there has been evidence that aerobic physical training promotes anti-inflammatory effects in asthma patients. Physical training improves BHR and EIB, asthma symptoms, clinical control, anxiety, and depression levels, sleep quality, lung function, exercise capacity, and dyspnea perception. Furthermore, physical training reduces medication consumption. The most commonly used exercise strategies are moderate aerobic and breathing exercises; however, other techniques, such as high-intensity interval training, have shown promising effects. In the present study, we reviewed the strategies and beneficial effects of exercise on clinical and pathophysiological asthma outcomes.

PSYCHOSOCIAL CHARACTERISTICS IN CHILDREN WITH ASTHMA REGARDING PHYSICAL ACTIVITY

ABSTRACT Introduction Children who are more active enjoy sports, have confidence in their ability to engage in physical activity, feel competent and perceive fewer barriers to physical activity. Objective Psychosocially characterize the asthmatic child’s relationship with enjoyable physical activity, physical self-concept, health and perceived quality of life. Method Eighty asthmatic children (age = 11.33 ± 1.10 years, body mass index [BMI] = 20.52 ± 3.83 kg/m2) and 80 healthy children (age = 11.18 ± 1.00 years, BMI = 20.81 ± 4.24 kg/m2) participated in the study. The Physical Activity Enjoyment Scale (PACES), Physical Activity Questionnaire for Children (PAQ-C), the Physical Self-concept Questionnaire (CAF) and the Pediatric Asthma Quality of Life Questionnaire (PAQLQ) were used. Results In the PACES questionnaire, healthy children had a better level of general physical activity while in the CAF questionnaire, significant differences were found in ability, physical fitness and general self-concept, which were higher in healthy children. There is a significant correlation between the PAQ-C and ability, general physical self-concept, PACES and total PAQLQ in asthmatic children. Conclusion Asthmatic children had lower levels of physical activity, physical self-concept and enjoyment in physical activity than healthy children. Level of evidence II; Retrospective study.

Anti-oxidant and Anti-inflammatory Effects of Aquatic Exercise in Allergic Airway Inflammation in Mice

Oxidative stress and inflammation are key pathways responsible for the pathogenesis of asthma. Aquatic exercise (AE) has been proven to elicit a variety of biological activities such as anti-oxidant and anti-inflammatory effects. However, although proper forms of AE provide beneficial health effects, incorrect forms and types of AE are potentially injurious to health. Several studies have investigated AE, but the relationship between types of AE and asthma has not been fully elucidated. This study evaluated the effects of two types of AE according to resistance on ovalbumin (OVA)-induced allergic airway inflammation in mice. BALB/c mice were subjected to OVA sensitization and challenge, and then to different types of AE including, walking and swimming, in a pool filled with water to a height of 2.5 and 13 cm for 30 min, respectively. AE reduced OVA-induced eosinophilic inflammation, airway hyperresponsiveness, and serum immunoglobulin E level. AE significantly inhibited increases in interleukin (IL)-4, IL-5, IL-13, histamine, leukotriene D4, and tryptase levels in bronchoalveolar lavage fluid (BALF). AE also effectively suppressed mucus formation, lung fibrosis, and hypertrophy of airway smooth muscle within the lung tissues. This exercise markedly reduced the levels of malondialdehyde while increased glutathione and superoxide dismutase (SOD) activity in lung tissues. Furthermore, AE significantly decreased tumor necrosis factor-α, IL-6 levels, and prostaglandin E2 production in BALF. The inhibitory effects of swimming on the levels of biomarkers related to oxidative stress and inflammation were greater than that of walking. These effects may have occurred through upregulation of NF-E2-related factor 2/heme oxygenase-1 signaling and suppression of mitogen-activated protein kinase/nuclear factor-κB pathway. Cumulative results from this study suggest that AE might be beneficial in mitigating the levels of biomarkers related to oxidative stress and inflammation. Thus, this therapy represents a crucial non-pharmacological intervention for treatments of allergic airway inflammation.

Impact of non-drug therapies on asthma control: A systematic review of the literature

Background: Despite growing access to effective therapies, asthma control still needs improvement. Many non-drug factors, such as allergens, air pollutants and stress also affect asthma control and patient quality of life, but an overview of the effectiveness of non-drug interventions on asthma control was lacking.

Objectives: To identify non-drug interventions likely to improve asthma control.

Methods: A systematic review of the available literature in Medline and the Cochrane Library was conducted in March 2017, without any time limit. Initial searching identified 884 potentially relevant clinical trial reports, literature reviews and meta-analyses, which were screened for inclusion using criteria of quality, relevance, and reporting outcomes based on asthma control.

Results: Eighty-two publications met the inclusion criteria. In general, the quality of the studies was low. Patient education programmes (22 studies) significantly improved asthma control. Multifaceted interventions (10 studies), which combined patient education programmes with decreasing exposure to indoor allergens and pollutants, significantly improved asthma control based on clinically relevant outcomes. Renovating homes to reduce exposure to allergens and indoor pollutants improved control (two studies). Air filtration systems (five studies) were effective, especially in children exposed to second-hand smoke. Most measures attempting to reduce exposure to dust mites were ineffective (five studies). Dietary interventions (eight studies) were ineffective. Promoting physical activity (five studies) tended to yield positive results, but the results did not attain significance.

Conclusion: Twenty-six interventions were effective in asthma control. Simultaneously combining several action plans, each focusing on different aspects of asthma management, seems most likely to be effective.

Long-term endurance running activity causes pulmonary changes depending on the receptor for advanced glycation end-products

The receptor for advanced glycation end-products (RAGE) is an immunoglobulin superfamily cell adhesion molecule predominantly expressed in the lung, but its pulmonary importance is incompletely understood. Since RAGE alters the respiratory mechanics, which is also challenged by endurance running activity, we studied the RAGE-dependent effect of higher running activity on selected lung parameters in a long-term animal model using wild-type (WT) and RAGE knockout (RAGE-KO) mice. Higher long-term running activity of mice was ensured by providing a running wheel for 8 months. Recording the running activity revealed that RAGE-KO mice are more active than WT mice. RAGE-KO caused an increased lung compliance which additionally increased after long-term running activity with minor limitation of the expiratory flow, whereas the respiratory mechanics of WT mice remained constant. Although RAGE-KO mice had a less dense alveolar-capillary barrier for immune cells, higher long-term running activity led only in WT mice to more leukocyte infiltrations in the lung tissue and aggregations of lymphoid cells in the airways. In this regard, WT mice of the activity group were also more sensitive to ventilation-mediated airway damages. In contrast to RAGE-KO mice of the activity group, lungs of WT mice did not show an increase in the cAMP response element-binding protein, a transcription factor regulating many pro-survival genes. Our findings suggest an important role of RAGE in the physical capability due to its effect on the lung compliance as well as RAGE as a mediator of airway damages caused by higher long-term running activity.

Effects of an unsupervised pedometer-based physical activity program on daily steps of adults with moderate to severe asthma: a randomized controlled trial

Supervised exercise has shown benefits for subjects with asthma, but little is known about the effectiveness of unsupervised physical activity on this population. We investigated the effects of a 12-week unsupervised pedometer-based physical activity program on daily steps and on clinical and psychological parameters of adults with asthma. Clinically stable adults with moderate to severe asthma were encouraged to take daily 30-minute walks and were randomized to pedometer and control groups. The pedometer group received pedometers and individualized daily step targets. Changes in daily steps (average of steps taken during six consecutive days), six-minute walk test (6MWT), health-related quality of life, asthma control and anxiety and depression levels were assessed 12 weeks after intervention and 24-28 weeks after randomization. Thirty-seven participants were recruited and 30 completed the intervention. At 12 weeks, the groups differed significantly in daily steps (adjusted average difference, 2488 steps; 95% confidence interval [CI], 803 to 4172; p = 0.005) and in the 6MWT (adjusted average difference, 21.9 m; 95% CI, 6.6 to 37.3; p = 0.006). These differences were not significant 24-28 weeks after randomization. The program was effective in increasing daily steps of adults with moderate to severe asthma 12 weeks after intervention.

Association between exercise-induced asthma and parental socio-economic status among school-aged adolescents in a semiurban community in Nigeria

This study investigated the prevalence and association between exercise-induced asthma (EIA) and parental socio-economic status (PSES) among school-aged adolescents in a semiurban community in Nigeria. Three hundred and eighty-five adolescents (185 male and 200 female adolescents) whose ages ranged between 10 and 19 years participated in this cross-sectional study. Participants were recruited from four government approved secondary schools in Ido-Ekiti using a multistage sampling technique. Peak expiratory flow rate (PEFR) was assessed at baseline and after 6-min run test (6-MRT) on a level playing ground using a standard peak flow meter. PEFR measurements were repeated at 5th, 10th, 15th, and 20th min post 6-MRT. Participants who had >15.0% PEFR fall were considered to have EIA. PSES was assessed using a validated socio-economic status questionnaire. Descriptive and inferential statistics were used to analyze data. Alpha level was set at P<0.05. The mean ages of males and females were 13.9±2.0 and 13.8±1.6 years, respectively. More than half of the participants, 58.2% had EIA (>15.0% PEFR scores) while 53.5% belonged to middle PSES class. There was no significant difference between PEFR scores of male and female participants at baseline and 5th min post 6-MRT. However, male participants had significant higher PEFR than the female counterparts at 10th (t=2.090, P=0.037), 15th (t=2.162, P=0.031), and 20th min (t=2.978, P=0.003). There was significant association between EIA and PSES (χ²=152.4; P=0.001). The prevalence of EIA is very high among school-aged adolescents in Nigeria and was significantly associated with PSES.

Protocol for a feasibility study to inform the development of a multicentre randomised controlled trial of asthma-tailored pulmonary rehabilitation versus usual care for individuals with severe asthma

INTRODUCTION

Pulmonary rehabilitation with core components of exercise training and multiprofessional education is an integral part of the management of patients with chronic lung disease. International guidelines for individuals with asthma recommend exercise as exercise improves symptoms, indices of cardiopulmonary efficiency, health status and psychosocial outcome. However, there is little published evidence evaluating safety and acceptability of exercise training for individuals with severe asthma and there are concerns regarding exercise-induced asthma. We propose a feasibility study for a multicentre randomised controlled trial (RCT) of asthma-tailored pulmonary rehabilitation (asthma-tailored PR) versus usual care in individuals with severe asthma.

METHODS AND ANALYSIS

The study will be conducted in three stages. Adults with severe asthma will be included if they have persistent symptoms despite being at step 4 or 5 of the British Thoracic Society guidelines. Stage 1: semistructured interviews will be used in a sample of 20-30 individuals with severe asthma to understand the experience and attitudes of this population towards exercise. Stage 2: eight focus groups of at least six healthcare professionals involved in the care of patients with severe asthma will be conducted to understand their attitudes towards exercise for this population. Stage 3: a small-scale RCT of the proposed multicentre RCT of asthma-tailored PR versus usual care for individuals with severe asthma will be conducted. The primary outcome measures will be recruitment, retention and adverse event rates. Semistructured interviews with participants of stage 3 will be used to identify further barriers or facilitators to participation in PR and the trial. Thematic analysis will be used for the interpretation of all interviews.

ETHICS AND DISSEMINATION

The study results will inform the design of a larger multicentre RCT. The National Research Ethics Service Committee East Midland approved the study protocol.

TRIAL REGISTRATION NUMBER

ISRCTN96143888.

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.

Interventions for managing asthma in pregnancy

BACKGROUND

Asthma is the most common respiratory disorder complicating pregnancy, and is associated with a range of adverse maternal and perinatal outcomes. There is strong evidence however, that the adequate control of asthma can improve health outcomes for mothers and their babies. Despite known risks of poorly controlled asthma during pregnancy, a large proportion of women have sub-optimal asthma control, due to concerns surrounding risks of pharmacological agents, and uncertainties regarding the effectiveness and safety of different management strategies.

OBJECTIVES

To assess the effects of interventions (pharmacologic and non-pharmacologic) for managing women's asthma in pregnancy on maternal and fetal/infant outcomes.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (2 June 2014) and the Cochrane Airways Group's Trials Register (4 June 2014).

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials comparing any intervention used to manage asthma in pregnancy, with placebo, no intervention, or an alternative intervention. We included pharmacological and non-pharmacological interventions (including combined interventions). Cluster-randomised trials were eligible for inclusion (but none were identified). Cross-over trials were not eligible for inclusion.We included multi-armed trials along with two-armed trials. We also included studies published as abstracts only.

DATA COLLECTION AND ANALYSIS

At least two review authors independently assessed trial eligibility and quality and extracted data. Data were checked for accuracy.

MAIN RESULTS

We included eight trials in this review, involving 1181 women and their babies. Overall we judged two trials to be at low risk of bias, two to be of unclear risk of bias, and four to be at moderate risk of bias.Five trials assessed pharmacological agents, including inhaled corticosteroids (beclomethasone or budesonide), inhaled magnesium sulphate, intravenous theophylline, and inhaled beclomethasone verus oral theophylline. Three trials assessed non-pharmacological interventions, including a fractional exhaled nitric oxide (FENO)-based algorithm versus a clinical guideline-based algorithm to adjust inhaled corticosteroid therapy, a pharmacist-led multi-disciplinary approach to management versus standard care, and progressive muscle relaxation (PMR) versus sham training.The eight included trials were assessed under seven separate comparisons. Pharmacological interventionsPrimary outcomes: one trial suggested that inhaled magnesium sulphate in addition to usual treatment could reduce exacerbation frequency in acute asthma (mean difference (MD) -2.80; 95% confidence interval (CI) -3.21 to -2.39; 60 women). One trial assessing the addition of intravenous theophylline to standard care in acute asthma did not report on exacerbations (65 women). No clear difference was shown in the risk of exacerbations with the use of inhaled beclomethasone in addition to usual treatment for maintenance therapy in one trial (risk ratio (RR) 0.36; 95% CI 0.13 to 1.05; 60 women); a second trial also showed no difference, however data were not clearly reported to allow inclusion in a meta-analysis. No difference was shown when inhaled beclomethasone was compared with oral theophylline for maintenance therapy (RR 0.88; 95% CI 0.59 to 1.33; one trial, 385 women). None of these trials reported on neonatal intensive care admissions.

SECONDARY OUTCOMES

inhaled magnesium sulphate in acute asthma was shown to improve lung function measures (one trial, 60 women); intravenous theophylline in acute asthma was not associated with benefits (one trial, 65 women). No clear differences were seen with the addition of inhaled corticosteroids to routine treatment in three trials (374 women). While inhaled beclomethasone, compared with oral theophylline, significantly reduced treatment discontinuation due to adverse effects in one trial (384 women), no other differences were observed, except for higher treatment adherence with theophylline. Four of the five trials did not report on adverse effects. Non-pharmacological interventionsPrimary outcomes: in one trial, the use of a FENO-based algorithm was shown to significantly reduce asthma exacerbations (RR 0.61; 95% CI 0.41 to 0.90; 220 women); and a trend towards fewer neonatal hospitalisations was observed (RR 0.46; 95% CI 0.21 to 1.02; 214 infants). No exacerbations occurred in one trial assessing pharmacist-led management; this approach did not reduce neonatal intensive care admissions (RR 1.50; 95% CI 0.27 to 8.32; 58 infants). One trial (64 women) assessing PMR did not report on exacerbations or neonatal intensive care admissions.

SECONDARY OUTCOMES

the use of a FENO-based algorithm to adjust therapy led to some improvements in quality of life scores, as well as more frequent use of inhaled corticosteroids and long-acting β-agonists, and less frequent use of short-acting β-agonists (one trial, 220 women). The FENO-based algorithm was associated with fewer infants with recurrent episodes of bronchiolitis in their first year of life, and a trend towards fewer episodes of croup for infants. Pharmacist-led management improved asthma control scores at six months (one trial, 60 women); PMR improved lung function and quality of life measures (one trial, 64 women). No other differences between comparisons were observed.

AUTHORS' CONCLUSIONS

Based on eight included trials, of moderate quality overall, no firm conclusions about optimal interventions for managing asthma in pregnancy can be made. Five trials assessing pharmacological interventions did not provide clear evidence of benefits or harms to support or refute current practice. While inhaled magnesium sulphate for acute asthma was shown to reduce exacerbations, this was in one small trial of unclear quality, and thus this finding should be interpreted with caution. Three trials assessing non-pharmacological interventions provided some support for the use of such strategies, however were not powered to detect differences in important maternal and infant outcomes. While a FENO-based algorithm reduced exacerbations, the effects on perinatal outcomes were less certain, and thus widespread implementation is not yet appropriate. Similarly, though positive effects on asthma control were shown with PMR and pharmacist-led management, the evidence to date is insufficient to draw definitive conclusions.In view of the limited evidence base, further randomised trials are required to determine the most effective and safe interventions for asthma in pregnancy. Future trials must be sufficiently powered, and well-designed, to allow differences in important outcomes for mothers and babies to be detected. The impact on health services requires evaluation. Any further trials assessing pharmacological interventions should assess novel agents or those used in current practice. Encouragingly, at least five trials have been identified as planned or underway.

Comparison between breathing and aerobic exercise on clinical control in patients with moderate-to-severe asthma: protocol of a randomized trial

BACKGROUND

Asthma is a chronic inflammatory airway disease characterized by reversible obstruction, inflammation and hyperresponsiveness to different stimulus. Aerobic and breathing exercises have been demonstrated to benefit asthmatic patients; however, there is no evidence comparing the effectiveness of these treatments.

METHODS/DESIGN

This is a prospective, comparative, blinded, and randomized clinical trial with 2 groups that will receive distinct interventions. Forty-eight asthmatic adults with optimized medical treatment will be randomly divided into either aerobic (AG) or breathing exercises (BG). Patients will perform breathing or aerobic exercise twice a week for 3 months, totalizing 24 sessions of 40 minutes each. Before intervention, both groups will complete an educational program consisting of 2 educational classes. Before and after interventions, the following parameters will be quantified: clinical control (main outcome), health related quality of life, levels of anxiety and depression, daily living physical activity and maximal exercise capacity (secondary outcome). Hyperventilation syndrome symptoms, autonomic nervous imbalance, thoracoabdominal kinematics, inflammatory cells in the sputum, fraction of exhaled nitric oxide (FENO) and systemic inflammatory cytokines will also be evaluated as possible mechanisms to explain the benefits of both interventions.

DISCUSSION

Although the benefits of breathing and aerobic exercises have been extensively studied, the comparison between both has never been investigated. Furthermore, the findings of our results will allow us to understand its application and suitability to patients that will have more benefits for every intervention optimizing its effect.

TRIAL REGISTRATION

Clinicaltrials.gov; Identifier: NCT02065258.

Effects of exercise training on airway hyperreactivity in asthma: a systematic review and meta-analysis

BACKGROUND

Although physical exercise is recommended for asthmatics, evidence on the effects of exercise on clinical key factors is still missing.

OBJECTIVES

We performed a systematic review and meta-analysis to determine the effect of exercise training (EXT) on quality of life (QoL), bronchial hyperresponsiveness (BHR), exercise-induced bronchoconstriction (EIB), lung function and exercise capacity, plus the factors affecting changes in QoL and exercise capacity in asthmatics after a period of EXT.

DATA SOURCES

A computerized search was conducted in MEDLINE, EMBASE, and CINAHL (last search on 15 November 2012), without language restriction, and references of original studies and reviews were searched for further relevant studies.

STUDY SELECTION

Two independent investigators screened full-text studies with asthmatic subjects undertaking EXT (defined as training for ≥7 days, ≥2 times per week, ≥5 training sessions in total) that assessed at least one of the following outcomes: QoL, airway hyperreactivity, forced expiratory volume in one second (FEV₁), peak expiratory flow (PEF), inflammatory parameters, exercise capacity, or exercise endurance. Potentially relevant studies were excluded if only respiratory muscle training, breathing exercises or yoga was performed, if asthmatic subjects with co-morbidities were investigated, if only data of mixed patient groups without separate results for asthmatics were presented, if training regimens were not sufficiently specified, if no numerical outcome data were presented, and if new long-term medication was introduced in addition to physical training. Of 500 potentially relevant articles, 13.4 % (67 studies including 2,059 subjects) met the eligibility criteria and were included for further analyses.

STUDY APPRAISAL AND SYNTHESIS METHODS

Data extraction and risk of bias assessment was performed according to the Cochrane Handbook for Systematic Reviews of Interventions. A meta-analysis of all randomized controlled trials (RCTs) was performed to determine the effect of EXT on asthma symptoms, BHR, EIB, FEV₁, exercise capacity and exercise endurance compared with control training. In addition, relative pre/post changes were analysed in all RCTs and controlled trials. Finally, multiple linear regression models were used to identify effects of relative changes in airway hyperreactivity (BHR or EIB), lung function (FEV₁ or PEF) and training hours on QoL and exercise performance.

RESULTS

In a total of 17 studies including 599 subjects, meta-analyses showed a significant improvement in days without asthma symptoms, FEV1 and exercise capacity while BHR only tended to improve. The analysis of relative within-group changes after EXT showed, however, significant improvements in QoL (17 %), BHR (53 %), EIB (9 %), and FEV1 (3 %) compared with control conditions. Multiple linear regression models revealed that changes in airway hyperreactivity and lung function significantly contributed to the change in QoL, while mainly the changes in airway hyperreactivity contributed to the change in exercise capacity.

CONCLUSION

EXT was shown to improve asthma symptoms, QoL, exercise capacity, BHR, EIB, and FEV1 in asthmatics and improvements in BHR explained part of the improvement in QoL and exercise capacity. Thus, physical activity should be recommended as a supplementary therapy to medication. However, more well controlled studies should be performed assessing the relationship of physical activity, QoL, airway hyperreactivity, lung function and especially airway inflammation as well as medication intake.

Pulmonary rehabilitation. Sociedad Española de Neumología y Cirugía Torácica (SEPAR)

Pulmonary rehabilitation (PR) has been shown to improve dyspnea, exercise capacity and health-related quality of life in patients with chronic obstructive pulmonary disease (COPD). PR has also shown benefits in diseases other than COPD but the level of evidence is lower. The fundamental components of PR programs are muscle training, education and chest physiotherapy. Occupational therapy, psychosocial support and nutritional intervention should also be considered. Home programs have been shown to be as effective as hospital therapy. The duration of rehabilitation programs should not be less than 8 weeks or 20 sessions. Early initiation of PR, even during exacerbations, has proven safe and effective. The use of oxygen or noninvasive ventilation during training is controversial and dependent on the patient's situation. At present, the best strategy for maintaining the benefits of PR in the long term is unknown. Longer PR programs or telemedicine could play a key role in extending the results obtained.

Role of leukotrienes in exercise-induced bronchoconstriction before and after a pilot rehabilitation training program

BACKGROUND

Whatever the initial stimulus for the exercise-induced bronchoconstriction (EIB) observed in asthmatic patients after exercise, the final effect is release of bronchoactive mediators, especially cysteinyl leukotrienes. Exercise rehabilitation training programs have been reported to protect against EIB. The exact mechanism(s) involved are not well understood. However, this protective effect may be related to adaptation and better coordination during exercise, depletion of cysteinyl leukotrienes, and/or a sluggish cysteinyl leukotriene response to exercise. The aim of the present work was to test the hypothesis that improvement in the incidence and severity of post-exercise bronchoconstriction after a rehabilitation training program is related to a change in leukotriene levels in response to exercise.

METHODS

Twenty asthmatic children aged 6-12 years and known to develop EIB were enrolled in an exercise training program for 12 weeks. The severity and incidence of EIB before and after training was assessed. Baseline and post-exercise sputum cysteinyl leukotriene levels were assessed before and after the training program.

RESULTS

The training program offered significant protection against EIB with a concomitant decrease in sputum cysteinyl leukotriene levels in response to exercise.

CONCLUSION

A training program can result in depletion and/or a sluggish cysteinyl leukotriene response to exercise and may be responsible for the protective effect of training programs on EIB. It is recommended to use an exercise rehabilitation training program as a complementary tool in the management of bronchial asthma, especially EIB.

The effects of a multisite aerobic exercise intervention on asthma morbidity in sedentary adults with asthma: the Ex-asthma study randomised controlled trial protocol

OBJECTIVE

Aerobic exercise can improve cardiovascular fitness and does not seem to be detrimental to patients with asthma, though its role in changing asthma control and inflammatory profiles is unclear. The main hypothesis of the current randomised controlled trial is that aerobic exercise will be superior to usual care in improving asthma control. Key secondary outcomes are asthma quality of life and inflammatory profiles.

DESIGN

A total of 104 sedentary adults with physician-diagnosed asthma will be recruited. Eligible participants will undergo a series of baseline assessments including: the asthma control questionnaire; the asthma quality-of-life questionnaire and the inflammatory profile (assessed from both the blood and sputum samples). On completion of the assessments, participants will be randomised (1:1 allocation) to either 12-weeks of usual care or usual care plus aerobic exercise. Aerobic exercise will consist of three supervised training sessions per week. Each session will consist of taking a short-acting bronchodilator, 10 min of warm-up, 40 min of aerobic exercise (50-75% of heart rate reserve for weeks 1-4, then 70-85% for weeks 5-12) and a 10 min cool-down. Within 1 week of completion, participants will be reassessed (same battery as at baseline). Analyses will assess the difference between the two intervention arms on postintervention levels of asthma control, quality of life and inflammation, adjusting for age, baseline inhaled corticosteroid prescription, body weight change and pretreatment dependent variable level. Missing data will be handled using standard multiple imputation techniques.

ETHICS AND DISSEMINATION

The study has been approved by all relevant research ethics boards. Written consent will be obtained from all participants who will be able to withdraw at any time.

RESULTS

The result will be disseminated to three groups of stakeholder groups: (1) the scientific and professional community; (2) the research participants and (3) the general public.

REGISTRATION DETAILS CLINICALTRIALSGOV IDENTIFIER

NCT00953342.

Effect of physical training on airway inflammation in bronchial asthma: a systematic review

Background

The majority of the global population cannot afford existing asthma pharmacotherapy. Physical training as an airway anti-inflammatory therapy for asthma could potentially be a non-invasive, easily available, affordable, and healthy treatment modality. However, effects of physical training on airway inflammation in asthma are currently inconclusive. The main objective of this review is to summarize the effects of physical training on airway inflammation in asthmatics.

Methods

A peer reviewed search was applied to Medline, Embase, Web of Science, Cochrane, and DARE databases. We included all observational epidemiological research studies and RCTs. Studies evaluating at least one marker of airway inflammation in asthmatics after a period of physical training were selected. Data extraction was performed in a blinded fashion. We decided a priori to avoid pooling of the data in anticipation of heterogeneity of the studies, specifically heterogeneity of airway inflammatory markers studied as outcome measures.

Results

From the initial 2635 studies; 23 studies (16 RCTs and 7 prospective cohort studies) were included. Study sizes were generally small (median sample size = 30). There was a reduction in C-reactive protein, malondialdehyde, nitric oxide, sputum cell counts and IgE in asthmatics with physical training. Mixed results were observed after training for fractional excretion of nitric oxide and bronchial hyperresponsiveness. The data was not pooled owing to significant heterogeneity between studies, and a funnel plot tests for publication bias were not performed because there were less than 10 studies for almost all outcome measures. Physical training intervention type, duration, intensity, frequency, primary outcome measures, methods of assessing outcome measures, and study designs were heterogeneous.

Conclusion

Due to reporting issues, lack of information and heterogeneity there was no definite conclusion; however, some findings suggest physical training may reduce airway inflammation in asthmatics.

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.

Factors associated with aerobic fitness in adolescents with asthma

BACKGROUND

In adolescents with asthma, information on factors associated with cardiorespiratory fitness levels is limited. The present study aimed to determine if objectively measured physical activity as well as potential relevant factors such as lung function, asthma exacerbations, use of inhaled corticosteroids or skin fold thickness are associated with direct measurements of peak oxygen uptake (V˙O2peak) in adolescents with asthma.

METHODS

From a nested case-control study at 13-years in the Environment and Childhood Asthma birth cohort study in Oslo, Norway, 86 13-years old adolescents with and 76 without asthma performed maximal running on a treadmill with V˙O2peak measured. The sum of four skin fold thicknesses was recorded, followed by wearing an activity monitor for four consecutive days. Lung function was measured by maximum forced expiratory flow-volume curves and body plethysmography. Asthma exacerbations and use of medication were registered by parental structured interview. Data were analysed using multiple regression analysis.

RESULTS

Vigorous physical activity (coefficients with 95% confidence intervals; 1.73 (0.32, 3.14)) and skin fold thickness -0.35 (-0.41, -0.28)) were significantly associated with V˙O2peak in adolescents with asthma. Neither use of inhaled corticosteroids, lung function nor number of asthma exacerbations was associated with V˙O2peak when taking physical activity and skin fold thickness into account. In the adolescents without asthma only skin fold thicknesses was negatively associated with V˙O2peak -3.5 (-4.1, -2.8).

CONCLUSIONS

V˙O2peak appears to be determined by vigorous physical activity level in Norwegian adolescents with asthma and not by asthma-related factors such as use of inhaled corticosteroids, lung function nor number of asthma exacerbations.

Effect of physical training on airway inflammation in animal models of asthma: a systematic review

BACKGROUND

There is little data on the effect of exercise on markers of airway inflammation in human asthmatics. The main objective of this review is to determine the effects of physical training on markers of airway inflammation in animal models of asthma.

METHODS

A peer reviewed search was applied to Medline, Embase, Web of Science, Cochrane, and DARE databases. Data extraction was performed in a blinded fashion.

RESULTS

From the initial 2336 studies, a total of 10 studies were selected for the final analysis. All were randomized controlled trials with low to moderate intensity training on ovalbumin-sensitized mice. In the exercised group of mice, there was a reduction in BAL eosinophils and Th-2 cytokines, no change in Th-1 cytokines, an increase in IL-10, and a reversal of airway remodeling. The data was not pooled owing to significant heterogeneity between studies, and a funnel plot test for publication bias was not performed because there were few studies reporting on any one outcome measure. The asthma models differed between studies in age and gender of mice, as well as in timing of physical training after sensitization. The risk of bias was unclear for some studies though this may not influence outcome measures. The accuracy of data extracted from graphics is unknown.

CONCLUSIONS

Physical training improves airway inflammation in animal asthma models.

Airways disorders and the swimming pool

Concerns have been expressed about the possible detrimental effects of chlorine derivatives in indoor swimming pool environments. Indeed, a controversy has arisen regarding the possibility that chlorine commonly used worldwide as a disinfectant favors the development of asthma and allergic diseases. The effects of swimming in indoor chlorinated pools on the airways in recreational and elite swimmers are presented. Recent studies on the influence of swimming on airway inflammation and remodeling in competitive swimmers, and the phenotypic characteristics of asthma in this population are reviewed. Preventative measures that could potentially reduce the untoward effects of pool environment on airways of swimmers are discussed.