Short period of high-intensity inspiratory muscle training improves inspiratory muscle strength in patients with chronic kidney disease on hemodialysis: a randomized controlled trial

Inspiratory Muscle Training in Patients Living With Chronic Kidney Disease and Receiving Hemodialysis: Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

People living with chronic kidney disease (CKD) and receiving hemodialysis (HD) have impaired respiratory muscle strength and endurance. The objective of this study was to systematically review the effects of inspiratory muscle training (IMT) on respiratory muscle strength, functional capacity, lung function, quality of life, endothelial function, and oxidative stress in people living with CKD and receiving HD.

METHODS

An electronic search was conducted from inception to June 2023. Randomized controlled trials that evaluated the effects of IMT on respiratory muscle strength, functional capacity, lung function, endothelial function, quality of life, or oxidative stress in adults living with CKD and receiving HD, compared with control, placebo IMT, or conventional physical therapy, were included.

RESULTS

Eight studies were included, totaling 246 people. The meta-analysis showed that IMT increased the maximum inspiratory pressure (MIP) by 22.53 cm H2O, the maximum expiratory pressure (MEP) by 19.54 cm H2O, and the distance covered in the 6-minute walk test by 77.63 m. Changes in lung function and quality of life were not observed. It was not possible to quantitatively analyze data on endothelial function and oxidative stress.

CONCLUSION

IMT improves MIP, MEP, and functional capacity in people living with CKD and receiving HD. IMT did not demonstrate significant results for lung function and quality of life. Effects on endothelial function and oxidative capacity remain uncertain.

IMPACT

Inspiratory muscle training improves MIP, MEP, and functional capacity in people living with CKD and receiving HD, compared with conventional physical therapy or controls or placebo intervention. Increases in functional capacity in this population are extremely important because of the relationship with the survival of these people.

Exercise Improves Respiratory Function, Body Fluid and Nitric Oxide in Hemodialysis Patients

Emerging evidence suggests that resistance training (RT) can mitigate respiratory muscle weakness in hemodialysis (HD) patients. However, the underlying mechanisms responsible for these beneficial effects remain unclear. The purpose of this study was to assess the impact of periodized RT on respiratory muscle strength and its relationship with handgrip strength (HGS), fat-free mass (FFM), nitric oxide (NO), and interdialytic weight gain (IWG) in HD patients. Thirty-three patients were randomly assigned to two groups: control (CTL; n=18) and RT (n=15). The RT group did not perform any additional exercise training specific to the respiratory tract. Maximal inspiratory (MIP) and expiratory (MEP) pressures, peak expiratory flow (PEF), HGS, FFM, NO, and IWG were measured before and after the intervention period. Participants in the RT group engaged in a 24-week RT program, three times per week. RT resulted in significant improvements in MIP, MEP, PEF, as well as enhancements in HGS, FFM, NO, and IWG (p<0.05). Notably, inverse correlations were observed between MIP (r=-0.37, p=0.03) and PEF (r=-0.4, p=0.02) with IWG. Thus, the amelioration of HGS and FFM coincided with a reduction in respiratory muscle weakness among HD patients. Decreased IWG and increased circulating NO are plausible mechanisms contributing to these improvements.

High-intensity intermittent inspiratory and abdominal muscle combined training in respiratory, swallowing and systemic muscles of healthy adults

BACKGROUND

Low-intensity continuous inspiratory muscle training improves its strength. The abdominal muscles are the main expiratory muscles, and their training may improve expiratory muscle strength. Respiratory muscle strength regulates coughing effectiveness, which is critical for pneumonia management. In older people, risk factors for the development of pneumonia were respiratory muscle weakness and swallowing impairment. Currently, the impact of high-intensity intermittent inspiratory and abdominal muscle combined training on the respiratory, swallowing, and systemic muscles is unclear.

OBJECTIVE

We aimed to explore the effects of high-intensity inspiratory muscle training combined with or without abdominal muscle training on respiratory muscle strength as well as the strength, mass, and performance of swallowing and systemic muscles.

METHODS

Twenty-eight healthy adults were divided into two groups. Participants performed high-intensity intermittent inspiratory muscle single or its combination with abdominal muscle training for 4 weeks. Respiratory muscle strength, swallowing muscle strength and mass, systemic muscle strength, mass and performance were measured at baseline, Week 2 and Week 4.

RESULTS

Both groups showed greater maximal respiratory pressures at Week 2 and Week 4 than baseline. Both groups showed improved tongue pressure and geniohyoid muscle thickness at Week 4. In addition, the combined training group improved body trunk muscle mass, handgrip strength and five-time chair stand test, whereas the single training group did not.

CONCLUSION

This study revealed that high-intensity inspiratory muscle training improved inspiratory muscle strength and swallowing muscle strength and mass. Moreover, inspiratory and abdominal muscle combined training showed an additional benefit of improving systemic muscle strength, mass and performance.

CLINICAL TRIAL REGISTRATION NUMBER

UMIN000046724; https://upload.umin.ac.jp/cgi-open-bin/ctr/index.cgi?ctrno=UMIN000046724.

Effects of different inspiratory muscle training protocols on functional exercise capacity and respiratory and peripheral muscle strength in patients with chronic kidney disease: a randomized study

BACKGROUND

Pathological changes were observed in the diaphragm due to abnormal renal function in chronic kidney disease (CKD). Inspiratory muscle training (IMT) has been suggested for patients with CKD; however, the most appropriate intensity for IMT has not been determined. Therefore, this study aimed to investigate the effects of different IMT protocols on respiratory muscle strength, quadriceps femoris muscle strength (QMS), handgrip muscle strength (HGS), functional exercise capacity, quality of life (QoL), pulmonary function, dyspnoea, fatigue, balance, and physical activity (PA) levels in patients with CKD.

METHODS

This randomized, controlled, single-blind study included 47 patients and they were divided into three groups: Group 1 (n = 15, IMT with 10% maximal inspiratory pressure (MIP)), Group 2 (n = 16, IMT with 30% MIP), and Group 3(n = 16; IMT with 60% MIP). MIP, maximal expiratory pressure (MEP), 6-min walking test (6-MWT), QMS, HGS, QoL, pulmonary function, dyspnoea, fatigue, balance, and PA levels were assessed before and after eight weeks of IMT.

RESULTS

Increases in MIP, %MIP, 6-MWT distance, and %6-MWT were significantly higher in Groups 2 and 3 than in Group 1 after IMT (p < 0.05). MEP, %MEP, FEF25-75%, QMS, HGS, and QoL significantly increased; dyspnoea and fatigue decreased in all groups (p < 0.05). FVC, PEF, and PA improved only in Group 2, and balance improved in Groups 1 and 2 (p < 0.05).

CONCLUSIONS

IMT with 30% and 60% MIP similarly improves inspiratory muscle strength and functional exercise capacity. IMT with 30% is more effective in increasing PA. IMT is a beneficial method to enhance peripheral and expiratory muscle strength, respiratory function, QoL and balance, and reduce dyspnoea and fatigue. IMT with %30 could be an option for patients with CKD who do not tolerate higher intensities.

TRIAL REGISTRATION

This study was retrospectively registered (NCT06401135, 06/05/2024).

Effect of respiratory muscle training in patients with chronic kidney disease: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

This systematic review and meta-analysis aimed to evaluate the effect of respiratory muscle training on respiratory muscle strength, lung function, cardiopulmonary fitness, and quality of life for chronic kidney disease patients.

METHODS

PubMed, Embase, Web of Science Core Collection, and Cochrane Central Register of Controlled Trials published randomized controlled trials that evaluated the effect of respiratory muscle training for chronic kidney disease patients from inception to December 2021, and rerun on September 2022. The quality of included studies was evaluated according to the Cochrane Collaboration's risk of bias tool-2. The outcomes were analyzed as mean differences with a fixed/random effect model. The strength of evidence was evaluated with the Grading of Recommendation, Assessment, Development, and Evaluation approach.

RESULTS

Eleven randomized controlled trials were included. All but two of the studies were in hemodialysis patients. The follow-up time range was 4 to 12 weeks. Compared to controls, respiratory muscle training significantly improved maximal expiratory pressure (mean difference = 17.36, p = 0.013), maximal inspiratory pressure (mean difference = 18.26, p = 0.002), forced expiratory volume at 1 second (mean difference = 0.20, p= 0.020), forced vital capacity (mean difference = 0.26, p = 0.008), but not for 6-minute walk test (mean difference = 39.85, p= 0.138).

CONCLUSIONS

As a non-pharmacological therapy, respiratory muscle training can effectively improve maximal expiratory pressure, maximal inspiratory pressure, forced expiratory volume at 1 second, and forced vital capacity in patients with chronic kidney disease and is safe for such populations.

Inspiratory-Expiratory Muscle Training Improved Respiratory Muscle Strength in Dialysis Patients: A Pilot Randomised Trial

End-stage kidney disease (ESKD) exposes patients to progressive physical deconditioning involving the respiratory muscles. The aim of this pilot randomized controlled trial was to determine the feasibility and effectiveness of low-intensity respiratory muscle training (RMT) learned at the hospital and performed at home. A group of ESKD patients (n = 22) were randomized into RMT or usual care (control group, CON) in a 1:1 ratio. The respiratory training was performed at home with an inspiratory-expiratory system for a total of 5 min of breathing exercises in a precise rhythm (8 breaths per minute) interspersed with 1 min of rest, two times per day on nondialysis days for a total of 4 weeks, with the air resistance progressively increasing. Outcome measures were carried out every 4 weeks for 3 consecutive months, with the training executed from the 5th to the 8th week. Primary outcomes were maximal inspiratory and expiratory pressure (MIP, MEP), while secondary outcomes were lung capacity (FEV1, FVC, MVV). Nineteen patients without baseline between-group differences completed the trial (T: n = 10; Age: 63 ± 10; Males: n = 12). Both MIP and MEP significantly improved at the end of training in the T group only, with a significant difference of MEP of 23 cmH₂O in favor of the RMT group (p = 0.008). No significant variations were obtained for FVC, FEV1 or MVV in either group, but there was a greater decreasing trend over time for the CON group, particularly for FVC (t = -2.00; p = 0.046). Low-fatiguing home-based RMT, with a simple device involving both inspiratory and expiratory muscles, may significantly increase respiratory muscle strength.

Effects of intradialytic inspiratory muscle training at different intensities on diaphragm thickness and functional capacity: clinical trial protocol in patients undergoing haemodialysis

INTRODUCTION

Patients with end-stage renal disease (ESRD) undergoing haemodialysis (HD) commonly present with a sedentary behaviour and reduced functional capacity, factors that can compromise their prognosis. Intradialytic inspiratory muscle training (IMT) can increase respiratory muscle strength and, consequently, improve functional capacity, besides being easy to apply, cheap and performed in a supervised setting. However, few studies show the effects of this type of training applied at different intensities in this population. This study aims to compare the effects of IMT at different intensities in adults with ESRD undergoing HD.

METHODS AND ANALYSIS

A randomised, double-blind, sham-controlled trial will be conducted on 36 subjects randomly allocated into three groups: IMT at intensities of 30% or 50% of maximal inspiratory pressure (intervention groups), or 10% of maximal inspiratory pressure (sham-IMT). All the interventions will be supervised and performed three times per week, for 12 weeks, totalling 36 sessions. The primary outcomes are the 6-minute walk test, diaphragm thickness and the response of VO₂peak post-intervention. Respiratory muscle strength, 24-hour ambulatory blood pressure measurement and the Kidney Disease Quality of Life 36-item short form survey will be evaluated as secondary outcomes.

ETHICS AND DISSEMINATION

This study has been approved by the Research Ethics Committee of the Hospital de Clínicas de Porto Alegre (ID: 2020-0458). The results of this study will be disseminated by conference presentations and peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT04660383.

Improving respiratory muscle strength and health status in burn patients: a randomized controlled trial

PURPOSE

Pulmonary complications are among the major disadvantages of burns. The present study aimed to determine the effect of inspiratory muscle training on respiratory muscle strength and health status in burned patients.

METHODS

The current randomized clinical trial was conducted on 64 burned patients in Burn Center of Imam Reza Hospital, Mashhad, Iran. In the intervention group, a Powerbreathe device (KH1 digital model) was used twice a day for 10 days, accompanied by the routine procedures and in the control group, only chest physiotherapy and incentive spirometer were used.

RESULTS

Before the intervention, the mean scores of respiratory muscle strength were 38.8 ± 10.1 and 35.8 ± 9.0 in the Powerbreathe group and control group, respectively (p = .206). After the intervention, the mean score of respiratory muscle strength of Powerbreathe group was 49.2 ± 11.8 and in the control group was 39.3 ± 8.5 (p < 0.001). Moreover, the mean scores of health status before the intervention in the burned patients were 66.3 ± 14.8 and 63.0 ± 17.3 in the Powerbreathe group and control group, respectively (p = 0.550). In the post-intervention phase, the mean health status score of the burned patients in the intervention and control groups were measured at 75.9 ± 14.1 and 66.7 ± 15.9, respectively (p = 0.019).

CONCLUSION

It seems that inspiratory muscle training improves respiratory muscle strength and health status in the burned patients. Therefore, the use of Powerbreathe is recommended for the prevention and improvement of pulmonary complications in patients with chest burns.

Respiratory muscle strength and quality of life in chronic kidney disease patients undergoing hemodialysis

Abstract Introduction: Hemodialysis (HD) sessions associated with the chronic kidney disease (CKD) repercussions may cause respiratory muscle impairment and limitations of daily living activities, which may compromise the quality of life. Objective: To evaluate respiratory muscle strength and quality of life in HD patients. Methods: A cross-sectional study involving CKD patients of both sexes undergoing HD. All were evaluated during HD, using an evaluation form containing personal and clinical data, presence of comorbidities, lifestyle (including self-reported physical activity) and vital signs. Respiratory muscle strength was analyzed by maximum inspiratory (MIP) and maximum expiratory (MEP) pressures by manovacuometer and quality of life using the SF-36 questionnaire. Results: Sixty-eight patients were evaluated (69.1% men), with a mean age of 54.9 ± 13.6 years. The MEP% was below of predicted (79.5 ± 25.7) and the MIP% was reduced only in women (77.8 ± 38.7). The MIP% was related to CKD time (p = 0.04) in men. The SF-36 domain that showed the most impairment was physical limitation [25.0 (13.0-67.0)], while mental health was the least impaired domain [72.0 (62.0-84.0)]. Those who reported the practice of physical activity obtained better results in vitality domain (p = 0.01). In the analysis stratified by sex, the functional capacity domain was less compromised in men who practiced self-reported physical activity (p = 0.02). Conclusion: CKD patients undergoing HD had a reduction in MEP relative to predicted, in addition to a greater impairment of MIP in men with longer CKD time and in women alone, although the clinical relevance of this finding is uncertain. Quality of life was more compromised in the physical limitation domain, where those who self-reported physical activity achieved better results in the domains of vitality (total sample) and functional capacity (men).

Benefits of inspiratory muscle training under indirect home supervision in patients with human T-cell lymphotropic virus type 1

Abstract Introduction: The presence of human T-cell lymphotropic virus type 1 (HTLV-1) associated with neuropathy (myelopathy/tropical spastic paraparesis - HAM/TSP), can generate morphological and functional changes in the respiratory system. As a preventive therapeutic possibility for respiratory dysfunctions, it is expected that the already conceptualized inspiratory muscle training, when performed at home, can be a therapeutic resource that favors adherence to treatment. Objective: To evaluate respiratory muscle strength in patients with HTLV-1 after participating in a home respiratory muscle training protocol under indirect supervision. Method: This was a clinical, longitudinal, prospective, quantitative, and single-center trial approved by the Research Ethics Committee of the State University of Pará, opinion no. 2.695.505 and registered in clinical trials NCT03829709. Six HTLV-1 patients participated in a 5-week home respiratory muscle training protocol lasting 30 minutes daily through a linear load inspiratory muscle trainer. For the characterization of the imposed load, they were submitted to manovacuometry during pre (T0), peri (T3), and post (T5) treatment. Results: Six individuals completed the program, of which 83.33% were female and 16.66% male. With the application of respiratory muscle training, it was possible to achieve a significant increase (p < 0.011) of the maximum inspiratory pressure as shown when comparing T0 (66.8±12.58) to T5 (115.08±31.78). Conclusion: This study identified an increase in inspiratory muscle strength after HTLV-1 patients participated in a home muscle training protocol under indirect supervision.