Patient perceived barriers to exercise and their clinical associations in difficult asthma

Effects of Moderate- Versus Vigorous-Intensity Exercise Training on Asthma Outcomes in Adults

BACKGROUND

The therapeutic effects of exercise have prompted calls for it to be embedded into standard asthma care, but evidence informing the optimal exercise intensity is lacking.

OBJECTIVE

This study aimed to compare the effects of moderate- and vigorous-intensity aerobic exercise training on asthma outcomes and inflammation.

METHODS

This was a 12-week randomized controlled trial in 46 adults with asthma randomized to either (1) 45-minute moderate-intensity exercise training 3 times/wk, (2) 30-minute vigorous-intensity exercise training 3 times/wk, or (3) the control group. Asthma-related quality of life (AQLQ), asthma control (ACQ), cardiorespiratory fitness, body composition, and airway and systemic inflammation were assessed before and after the intervention.

RESULTS

Forty-one participants completed the study (89% retention). The moderate-intensity group had a statistically and clinically significant improvement in AQLQ (0.63 [0.33-0.93], P < .001) and ACQ (-0.51 [-0.83 to -0.19], P = .003) relative to control. The vigorous-intensity group had a statistically, but not clinically, significant improvement in AQLQ (0.46 [0.14-0.80], P = .007) and ACQ (-0.36 [-0.69 to -0.02], P = .040) relative to control. After moderate-intensity training, there was a reduction in sputum macrophage (-1341 [-2491 to -191] × 104/mL, P = .024) and lymphocyte (-114 [-220 to -8] × 104/mL, P = .036) counts relative to control. A reduction in android fat mass, but not a change in fitness, was associated with improved AQLQ (rs = -0.341, P = .030) and reduced sputum IL-6 (rs = 0.422, P = .013).

CONCLUSIONS

Our findings suggest that both moderate-intensity and vigorous-intensity aerobic exercise training are associated with improvements in clinical asthma outcomes and, therefore, both intensities could be recommended as an adjuvant asthma therapy.

Basis of preventive and non-pharmacological interventions in asthma

Asthma is one of the most common atopic disorders in all stages of life. Its etiology is likely due to a complex interaction between genetic, environmental, and lifestyle factors. Due to this, different non-pharmacological interventions can be implemented to reduce or alleviate the symptoms caused by this disease. Thus, the present narrative review aimed to analyze the preventive and non-pharmacological interventions such as physical exercise, physiotherapy, nutritional, ergonutritional, and psychological strategies in asthma treatment. To reach these aims, an extensive narrative review was conducted. The databases used were MedLine (PubMed), Cochrane (Wiley), Embase, PsychINFO, and CinAhl. Asthma is an immune-mediated inflammatory condition characterized by increased responsiveness to bronchoconstrictor stimuli. Different factors have been shown to play an important role in the pathogenesis of asthma, however, the treatments used to reduce its incidence are more controversial. Physical activity is focused on the benefits that aerobic training can provide, while physiotherapy interventions recommend breathing exercises to improve the quality of life of patients. Nutritional interventions are targeted on implement diets that prioritize the consumption of fruits and vegetables and supplementation with antioxidants. Psychological interventions have been proposed as an essential non-pharmacological tool to reduce the emotional problems associated with asthma.

Key Considerations When Addressing Physical Inactivity and Sedentary Behaviour in People with Asthma

People with asthma tend to be less physically active and more sedentary than people without asthma. This narrative review aimed to present key considerations when addressing physical inactivity and sedentary behaviour in people with asthma by identifying barriers and facilitators, determinants and correlates, and intervention approaches. Using a search strategy, electronic databases were searched for relevant studies. Data extracted from studies were qualitatively synthesised. A total of 26 studies were included in the review. Six studies reported asthma symptoms as a barrier to physical activity, while four studies reported having a supportive network as a physical activity facilitator. Across studies, physical activity correlates/determinants were pulmonary function, exercise capacity, body mass index, dyspnoea, psychological health, and asthma control. Interventions that effectively improved physical activity in the short term were a step-based prescription programme, a weight loss programme incorporating aerobic and resistance training, and a weight loss lifestyle intervention, while a high-intensity interval training pulmonary rehabilitation program was effective in the long term. The collective findings suggest that a personalised physical activity programme incorporating different strategies is needed. There was minimal evidence to provide recommendations to optimise sedentary behaviour in asthma, and more research is needed on the topic.

Exercise and asthma - Trigger or treatment?

Exercise is one of the most commonly reported symptom triggers for people with asthma. However, a growing body of evidence indicates that regular exercise and physical activity are associated with improved clinical and patient reported outcomes. In this article, we summarise and consolidate recent original studies evaluating exercise and physical activity profiles in people with asthma and provide an up-to-date perspective concerning the role of exercise training and physical activity promotion in the context of asthma management. To conclude, we identify key unmet needs and provide directions for future research.

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.

Increased physical activity reduces sleep disturbances in asthma: A randomized controlled trial

BACKGROUND AND OBJECTIVE

Individuals with asthma are more likely to develop sleep-disordered breathing. Exercise training improves sleep; however, the effect of physical activity (PA) on improving sleep quality remains unknown. This study had two objectives: (i) to evaluate the effect of a behavioural intervention to increase physical activity in daily living (PADL) on sleep quality in adults with asthma; (ii) to verify the association between a change in sleep quality, quality of life, anxiety, depression and asthma symptoms.

METHODS

This randomized controlled clinical trial included adults physically inactive with asthma. Participants were randomized into the control (CG; n = 25) and intervention groups (IG; n = 24). IG was submitted to a behavioural intervention to increase PADL, and CG received the usual care. Pre- and post-intervention assessments of sleep quality (by actigraphy and questionnaire), PADL level (by accelerometry), asthma control, health-related quality of life and anxiety and depression levels were conducted.

RESULTS

Both groups were similar at baseline. After the intervention, IG increased daily steps and moderate to vigorous PA levels. IG also improved sleep efficiency and latency as well as increased asthma-symptom-free days compared to CG. In addition, a greater proportion of participants in the IG had improved sleep quality after the intervention. Lastly, IG presented clinical improvement in the asthma-related quality of life questionnaire and a reduction in anxiety symptoms.

CONCLUSION

Our results demonstrate that a behavioural intervention can increase PA, enhance behavioural sleep quality, efficiency and quality of life and reduce asthma and anxiety symptoms.

Comparing the Effect of Acute Moderate and Vigorous Exercise on Inflammation in Adults with Asthma: A Randomized Controlled Trial

Rationale: Exercise is associated with improvements in asthma; however, the mechanisms responsible are not clear. Exercise induces changes in systemic inflammation, and it is possible that these inflammatory effects extend to the airways of people with asthma. Studies in healthy adults suggest inflammatory responses are dependent on exercise intensity: Although acute moderate exercise is antiinflammatory, acute vigorous exercise appears to be neutral or proinflammatory. The effect of exercise intensity on inflammation has not been investigated in people with asthma. Objectives: To compare acute changes in airway and systemic inflammation after a bout of moderate or vigorous exercise in physically inactive adults with asthma and to establish whether these effects differ according to asthma phenotype. Methods: Participants were randomized to either 1) control (no intervention), 2) 45 minutes of moderate exercise, or 3) 30 minutes of vigorous exercise. Induced sputum and blood samples were collected at baseline and 4 hours after intervention. Results: Fifty-six participants (75% female; mean age, 33.4 [9.9] yr) completed the trial. Moderate exercise induced a significant reduction in sputum eosinophil count (-173 [-337 to -10]; P = 0.032) and sputum percentage eosinophils (-2.2 [-4.9 to 0.5]; P = 0.049) relative to control. Vigorous exercise had no effect on airway inflammation. The antiinflammatory effects of moderate exercise were greatest in participants with eosinophilic asthma, with larger reductions in sputum eosinophils and larger increases in plasma interleukin (IL)-1ra than seen in participants with noneosinophilic asthma. Vigorous exercise induced a systemic proinflammatory response in participants with eosinophilic asthma, indicated by an increase in serum IL-5 and IL-1β; however, this had no effect on airway inflammation. Conclusions: Exercise intensity modifies the acute inflammatory response to exercise in adults with asthma. Although a bout of moderate exercise is associated with a reduction in eosinophilic airway inflammation, vigorous exercise has no effect on airway inflammation. Interestingly, the effects of moderate exercise vary by asthma phenotype, with greater antiinflammatory effects in participants with eosinophilic asthma. Future studies should examine the impact of exercise training at different intensities on inflammation and clinical asthma outcomes. Clinical trial registered with the Australian New Zealand Clinical Trials Registry (ACTRN 12615000294550).

Exercise Training Programs Improve Cardiorespiratory and Functional Fitness in Adults With Asthma: A SYSTEMATIC REVIEW AND META-ANALYSIS

PURPOSE

This systematic review aimed to identify the characteristics and determine the effects of exercise interventions on improving health-related physical fitness in adults with asthma.

REVIEW METHODS

A systematic search was completed in MEDLINE, CINAHL, Embase, and SPORTDiscus for peer-reviewed publications of experimental studies that investigated the effects of an exercise training intervention on performance-based health-related physical fitness outcomes in adults with asthma. Two reviewers independently screened studies for inclusion according to predetermined criteria and performed data extraction and quality assessment of included studies.

SUMMARY

Forty-five articles were included, in which results for 39 unique studies were reported. Subjects (n = 2135) were aged 22 ± 4 to 71 ± 11 yr with mild-severe asthma. Most exercise programs used aerobic exercise, either alone or in combination with resistance or breathing/stretching exercises. The most common exercise program characteristics were supervised moderate-to-vigorous intensity aerobic exercise performed for 30-45 min 3 d/wk. Meta-analyses revealed significant improvements in cardiorespiratory fitness (V˙o2peak: unstandardized mean difference [MD] 3.1 mL/kg/min, 95% CI, 1.9-4.3), functional fitness (walking distance: MD 41 m, 95% CI, 27-54), and overall health-related physical fitness (standardized mean difference [SMD] 0.67, 95% CI, 0.46-0.89) in favor of groups who underwent experimental exercise training interventions. Aerobic exercise elicited superior improvements in health-related physical fitness compared with breathing/stretching exercise (SMD 0.47, 95% CI, 0.14-0.81).Supervised exercise training programs, particularly those aerobic in nature, are effective in eliciting clinically meaningful improvements in cardiorespiratory and functional fitness in adults with asthma.PROSPERO registration ID number = CRD42018092828.

Experiences of exercise in patients with asthma: qualitative analysis of discussions in a UK asthma online community

BACKGROUND

Engagement with exercise in adults with asthma is suboptimal. Limited information is available regarding factors affecting engagement with exercise.

AIM

To explore experiences of exercise and linked unmet needs in adults with asthma.

DESIGN & SETTING

Qualitative thematic analysis of posts in a UK asthma online community, written between 2015 and 2020.

METHOD

Posts were identified using keywords searches. Posts in the 'Exercise' topic section were additionally included. Thematic analysis of posts was undertaken.

RESULTS

143 relevant posts were analysed. 92 participants were identified through posts (11M, 33F, 48 gender not stated, aged 26-73 years). Emerging themes included: fear of experiencing asthma symptoms during exercise, lack of information about how to deal with symptoms, external barriers, emotional response, and involvement of healthcare providers. Environmental factors, concomitant life stressors, distrust of healthcare professionals and embarrassment of displaying asthma symptoms during exercise were barriers to engagement. Facilitators included experiencing positive health outcomes following exercise and positive discussions regarding exercise with healthcare professionals. Strategies participants developed to enable exercise were warming up, increasing reliever and preventer inhalers when exercising and finding exercises felt as enjoyable.

CONCLUSION

Future interventions to address fears of exercise-induced physical symptoms, and clear instructions on the use of inhalers when exercising are needed. Exploring patients' attitudes to exercise in clinical consultations, especially in primary care, may be beneficial.

Evidence Around the Impact of Pulmonary Rehabilitation and Exercise on Redox Status in COPD: A Systematic Review

Introduction: Oxidative stress is increasingly recognized as a significant factor in the pathogenesis of chronic obstructive pulmonary disease (COPD). Pulmonary rehabilitation, a major component of which is prescribed exercise, is essential in COPD care. Regular exercise has been proposed to increase antioxidant defenses and overall enhance the ability of the body to counteract oxidative stress. However, the mechanisms through which it improves COPD outcomes remain unclear.

Objectives: We aimed to appraise the current evidence around the impact of pulmonary rehabilitation on redox status, compared with other exercise interventions, to gain an understanding of optimal exercise interventions to modify this pathophysiological mechanism.

Methods: We performed a systematic review through searching CENTRAL, MEDLINE, PubMed, Scopus, and Web of Science. Results were independently reviewed and relevant studies were selected by two independent assessors. Studies were assessed by two independent people using the modified RoB 2 tool and discrepancies were resolved through discussion.

Results: We identified 1,710 records and 1,117 records after duplicate removal. Six studies were included in the final analysis. The evidence available was low quality and four studies had high risk of bias and two studies had unclear risk of bias. Studies were small (15–56 participants); only two included details of randomization and patient cohorts were of varying ages and poorly described. Differences in smoking status and previous exercise levels, which are known to impact redox status, were not well documented. Studies were not standardized and used different exercise doses and measured different outcomes. One study reported lower malondialdehyde levels, a marker of lipid peroxidation, after pulmonary rehabilitation, compared with control. However, one study saw no difference following whole-body vibration training and another study showed higher malondialdehyde levels following supervised modified arm swing exercise compared with control.

Conclusion: Understanding the impact of exercise on oxidative stress in COPD could lead to tailored exercise programs and modification of pathological mechanisms. However, we identify a lack of high-quality evidence to determine this. Larger, standardized, and high quality randomized controlled trials (RCTs) are essential, which use carefully clinically characterized and controlled cohorts to determine the relative impact of different exercise interventions on redox status to guide COPD management. We propose an idealized RCT design, which could be used to try and meet this need.

Physical activity and childhood asthma control: Mediation and moderation role of body mass index

BACKGROUND

Physical activity (PA) may be associated with asthma management. Whether PA is associated with childhood asthma control is not well studied, and the role of body mass index (BMI) in this association remains unclarified. This study aimed to evaluate the association between PA and childhood asthma control and investigate the potential mediating and modifying role of BMI in the association.

METHODS

This cross-sectional study involved 303 asthmatic children aged 5-14 years. Information on PA was collected from children. Asthma control was assessed using a valid questionnaire by children and their parents. Height and weight were objectively measured and BMI was calculated and classified. Multiple linear regression, mediation, and moderation analyses were performed.

RESULTS

There was a positive association between PA and childhood asthma control with adjustment for variates (B = 0.144, p = .012). Mediation analysis indicated that BMI status negatively mediated the association (estimate = -0.656, 95% credit interval: -1.645, -0.006), and such indirect effect is lower than the direct effect (indirect effect/direct effect = 58.3%). No evidence of effect modification by BMI was observed (P_interaction = 0.516). Stratified analyses showed that the significant association was only observed in children with overweight/obesity (normal weight: B = 0.863, p = .189; overweight/obese: B = 1.494, p = .044).

CONCLUSIONS

Increased PA is associated with improved childhood asthma control, especially for children with higher BMI. BMI exhibited a negative effect but not effect modification in this association. PA should be encouraged to improve asthma control for asthmatic children. Besides, mechanisms other than weight loss may explain the association.

Exercise Training Induces a Shift in Extracellular Redox Status with Alterations in the Pulmonary and Systemic Redox Landscape in Asthma

Redox dysregulation and oxidative stress have been implicated in asthma pathogenesis. Exercise interventions improve symptoms and reduce inflammation in asthma patients, but the underlying mechanisms remain unclear. We hypothesized that a personalised exercise intervention would improve asthma control by reducing lung inflammation through modulation of local and systemic reactive species interactions, thereby increasing antioxidant capacity. We combined deep redox metabolomic profiling with clinical assessment in an exploratory cohort of six female patients with symptomatic asthma and studied their responses to a metabolically targeted exercise intervention over 12 weeks. Plasma antioxidant capacity and circulating nitrite levels increased following the intervention (p = 0.028) and lowered the ratio of reduced to oxidised glutathione (p = 0.029); this was accompanied by improvements in physical fitness (p = 0.046), symptoms scores (p = 0.020), quality of life (p = 0.046), lung function (p = 0.028), airway hyperreactivity (p = 0.043), and eosinophilic inflammation (p = 0.007). Increased physical fitness correlated with improved plasma antioxidant capacity (p = 0.019), peak oxygen uptake and nitrite changes (p = 0.005), the latter also associated with reductions in peripheral blood eosinophil counts (p = 0.038). Thus, increases in “redox resilience” may underpin the clinical benefits of exercise in asthma. An improved understanding of exercise-induced alterations in redox regulation offers opportunities for greater treatment personalisation and identification of new treatment targets.

Unravelling the mechanisms driving multimorbidity in COPD to develop holistic approaches to patient-centred care

COPD is a major cause of morbidity and mortality worldwide. Multimorbidity is common in COPD patients and a key modifiable factor, which requires timely identification and targeted holistic management strategies to improve outcomes and reduce the burden of disease.We discuss the use of integrative approaches, such as cluster analysis and network-based theory, to understand the common and novel pathobiological mechanisms underlying COPD and comorbid disease, which are likely to be key to informing new management strategies.Furthermore, we discuss the current understanding of mechanistic drivers to multimorbidity in COPD, including hypotheses such as multimorbidity as a result of shared common exposure to noxious stimuli (e.g. tobacco smoke), or as a consequence of loss of function following the development of pulmonary disease. In addition, we explore the links to pulmonary disease processes such as systemic overspill of pulmonary inflammation, immune cell priming within the inflamed COPD lung and targeted messengers such as extracellular vesicles as a result of local damage as a cause for multimorbidity in COPD.Finally, we focus on current and new management strategies which may target these underlying mechanisms, with the aim of holistic, patient-centred treatment rather than single disease management.