Clinical safety and hemodynamic, cardiac autonomic and inflammatory responses to a single session of inspiratory muscle training in obstructive sleep apnea

Respiratory muscle training for obstructive sleep apnea: Systematic review and meta-analysis

Obstructive sleep apnea is the most common sleep disorder. This review aims to evaluate the effectiveness and safety of respiratory muscle training in the treatment of patients with obstructive sleep apnea. The study protocol was registered in Prospero Platform (CRD42018096980). We performed searches in the main databases: Medical Literature Analysis and Retrieval System Online (MEDLINE) via Pubmed; Excerpta Medica dataBASE (Embase) via Elsevier; Cochrane Central Register of Controlled Trials (CENTRAL) via Cochrane Library; Latin American and Caribbean Literature on Health Sciences (LILACS) through the Portal of the Virtual Health Library and Physiotherapy Evidence Database (PEDro) for all randomised-controlled trials published before July 2022. The randomised-controlled trials were assessed for risk of bias and certainty of evidence. Thirteen randomised-controlled trials were included. All studies had an overall high risk of bias. Inspiratory muscle training probably improves systolic blood pressure and sleepiness when compared with sham. However, inspiratory muscle training probably does not improve diastolic blood pressure and maximum expiratory pressure, and may not be superior to sham for apnea-hypopnea index, forced expiratory volume in 1 s, forced vital capacity, sleep quality and quality of life. In addition, it is uncertain whether there is any effect of inspiratory muscle training on maximum inspiratory pressure and physical capacity. Inspiratory muscle training may also improve maximum inspiratory pressure and maximum expiratory pressure compared with oropharyngeal exercises. However, it may not be superior for apnea-hypopnea index, sleep quality, sleepiness, quality of life and functional capacity. When associated with physical exercise, inspiratory muscle training may not be superior to physical exercise alone for maximum inspiratory pressure, maximum expiratory pressure, systolic and diastolic blood pressure, and functional capacity. At the same time, when associated with cardiac rehabilitation exercises, inspiratory muscle training may reduce apnea-hypopnea index, improve inspiratory muscle strength, sleepiness and sleep quality compared with cardiac rehabilitation alone. However, it may not be superior for improving quality of life. Regarding expiratory muscle training, it may improve expiratory muscle strength and sleep quality, but not sleepiness when compared with sham. The evidence on the effects of expiratory muscle training in apnea-hypopnea index is very uncertain.

Effects of inspiratory muscle training on the severity of obstructive sleep apnea in individuals after stroke: a protocol for a randomized controlled trial

BACKGROUND

Obstructive sleep apnea (OSA) is the most common form of sleep-disordered breathing in cerebrovascular diseases, requiring a multidisciplinary approach. There are few studies evaluating the effects of inspiratory muscle training (IMT) in individuals with OSA and the findings regarding the possible effect on apnea hypopnea index (AHI) reduction are controversial.

OBJECTIVE

This protocol for a randomized clinical trial will assess the effects of IMT on the severity of obstructive sleep apnea, sleep quality, and daytime sleepiness in individuals after stroke participating in a rehabilitation program.

METHODS

This study will be a randomized controlled trial with blinded assessors. Forty individuals after stroke will randomized to two groups. For 5 weeks, both groups will participate in the rehabilitation program activities, including aerobic exercise, resistance training, and educational class when they will receive guidance on the behavioral management of OSA. The experimental group will also perform high-intensity IMT 5 times a week, for 5 weeks, consisting initially of five sets of five repetitions achieving 75% of the maximal inspiratory pressure, increasing one set each week, totaling nine sets at the end of training. The primary outcome will be the severity of OSA measured as AHI at 5 weeks. Secondary outcomes will include sleep quality measured by the Pittsburgh Sleep Quality Index (PSQI) and daytime sleepiness measured by Epworth Sleepiness Scale (ESS). Outcomes will be collected by a researcher blinded to group allocation at baseline (week 0), after intervention (week 5), and 1 month beyond intervention (week 9).

TRIAL REGISTRATION

Clinical Trials Register: NCT05135494.

A hypotensive protocol of inspiratory muscle strength training: Systematic review and meta-analysis with trial sequential analysis

The aim of this study was to evaluate the hypotensive effect and optimal protocol of inspiratory muscle resistance training (IMST). Randomized controlled trials using IMST to lower blood pressure (BP) were retrieved from 12 databases as of July 2022. A meta-analysis of BP and heart rate variability (HRV) was performed and a trial sequence analysis was performed using trial sequential analysis (TSA) software. Twelve articles (n = 386 participants) from five countries were included, with a mean quality score of 5.83. IMST achieved significant results in reducing systolic, diastolic, and mean arterial pressure (-7.93 [-12.08, -3.78]; -3.80 [-6.08, -1.53]; -4.90 [-13.76, 3.96]). Furthermore, TSA has shown that the findings for systolic and diastolic BP are conclusive. Finally, considerable variation remained between studies when analyzing HRV. The overall hypotensive effect of IMST was demonstrated by the TSA and was well tolerated in different populations. Of these, two interventions, high resistance or low resistance combined with slow breathing, showed the best efficacy under an 8-week exercise intervention. In addition, the process of lowering BP by modulating sympathetic vagal activity has not been further confirmed in this study. Future long-term interventions, especially those over 3 months, are needed to observe the prolonged antihypertensive effects and modulatory mechanisms; controlling for variables such as respiratory rate and executing more rigorous studies to further explore antihypertensive options.

Effects of inspiratory muscle training on blood pressure- and sleep-related outcomes in patients with obstructive sleep apnea: a meta-analysis of randomized controlled trials

PURPOSE

Obstructive sleep apnea (OSA) is frequently accompanied by hypertension, resulting in cardiovascular comorbidities. Continuous positive airway pressure is a standard therapy for OSA but has poor adherence. Inspiratory muscle training (IMT) may reduce airway collapsibility and sympathetic output, which may decrease OSA severity and blood pressure. In this meta-analysis of randomized controlled trials (RCTs), we evaluated the efficacy of IMT in patients with OSA.

METHODS

We searched PubMed, EMBASE, Cochrane Library, Web of Science, and ClinicalTrials.gov databases for relevant RCTs published before November 2022.

RESULTS

Seven RCTs with a total of 160 patients with OSA were included. Compared with the control group, the IMT group exhibited significantly lower systolic and diastolic blood pressure (mean difference [MD]: - 10.77 and - 4.58 mmHg, respectively), plasma catecholamine levels (MD: - 128.64 pg/mL), Pittsburgh Sleep Quality Index (MD: - 3.06), and Epworth Sleepiness Scale score (MD: - 4.37). No significant between-group differences were observed in the apnea-hypopnea index, forced vital capacity (FVC), ratio of forced expiratory volume in 1 s to FVC, or adverse effects. The data indicate comprehensive evidence regarding the efficacy of IMT for OSA. However, the level of certainty (LOC) remains low.

CONCLUSION

IMT improved blood pressure- and sleep-related outcomes without causing adverse effects and may thus be a reasonable option for lowering blood pressure in patients with OSA. However, additional studies with larger sample sizes and rigorous study designs are warranted to increase the LOC.

Time-efficient, high-resistance inspiratory muscle strength training for cardiovascular aging

Cardiovascular diseases (CVD) remain the leading cause of death in developed and developing societies and aging is the primary risk factor for CVD. Much of the increased risk of CVD in midlife/older adults (i.e., adults aged 50 years and older) is due to increases in blood pressure, vascular endothelial dysfunction and stiffening of the large elastic arteries. Aerobic exercise training is an effective lifestyle intervention to improve CV function and decrease CVD risk with aging. However, <40% of midlife/older adults meet guidelines for aerobic exercise, due to time availability-related barriers and other obstacles to adherence. Therefore, there is a need for new lifestyle interventions that not only improve CV function with aging but also promote adherence. High-resistance inspiratory muscle strength training (IMST) is an emerging, time-efficient (5 min/day) lifestyle intervention. Early research suggests high-resistance IMST may promote adherence, lower blood pressure and potentially improve vascular endothelial function. However, additional investigation will be required to more definitively establish high-resistance IMST as a healthy lifestyle intervention for CV aging. This review will summarize the current evidence on high-resistance IMST for improving CV function with aging and will identify key research gaps and future directions.