Obstructive Sleep Apnea in Cardiac Rehabilitation Patients

Effect of Sleep-Disordered Breathing on Exercise Capacity after Myocardial Infarction - A Cross-Sectional Study

Background

Exercise capacity reflects the cardiovascular risk after myocardial infarction (MI). The study aims to evaluate the impact of sleep-disordered breathing (SDB) on exercise capacity after MI.

Methods

Consecutive patients referring to outpatient cardiac rehabilitation up to 28 days after MI and participating in the Polish Managed Care after Acute Myocardial Infarction (MC-AMI) program were included. On admission, we assessed the presence and the severity of SDB using the home sleep apnea test (HSAT), patients' maximum exercise capacity on a treadmill exercise stress test (EST), and a 6-minute walk test (6MWT), as well as the effect of SDB on the results obtained. In the multivariate analysis, we verified the strength of the observed associations concerning age, anthropometric parameters, and left ventricular ejection fraction (LVEF).

Results

A total of 254 patients aged 60.00 (interquartile range 51.00-67.00), including 39 (15.4%) women, with technically adequate HSAT, constituted the study group. Mild SDB was found in 82 (32.3%), moderate in 54 (21.3%), and severe in 51 (20.1%) patients. Among those diagnosed with SDB, obstructive sleep apnea (OSA) was dominant in 167 (89.8%). With the worsening of SDB, the distance in 6MWT and the maximum physical exertion achieved in EST, expressed in metabolic equivalents (METs) and maximal heart rate (MHR), decreased. The linear regression analysis confirmed the following: (1) inversely proportional relationship between the respiratory event index and METs, MHR, and 6MWT distance (p = 0.005, p = 0.008, and p = 0.004), and the maximum apnea duration and MET and 6MWT distance (p = 0.042 and p = 0.002); and (2) directly proportional relationship between mean arterial oxygen saturation ( SpO 2 ) during sleep and MET, MHR, and 6MWT distance (p = 0.019, p = 0.006, and p = 0.013), and minimum SpO 2 and MET and MHR (p = 0.040 and p < 0.001). However, the independent risk factors for impaired exercise capacity, determined using multivariable regression analysis, were age, female sex, higher body mass index (BMI), and decreased LVEF, but not SDB parameters.

Conclusions

SDB negatively impacts exercise capacity after MI. However, the strength of this association may be less pronounced due to the interaction of risk factors common for SDB and impaired exercise capacity, e.g., sex, age, BMI, and LVEF.

Obstructive Sleep Apnea and a Comprehensive Remotely Supervised Rehabilitation Program: Protocol for a Randomized Controlled Trial

BACKGROUND

Obstructive sleep apnea (OSA) is characterized by recurrent, intermittent partial or complete obstruction of the upper respiratory tract during sleep, which negatively affects the patient's daily quality of life (QoL). Middle-aged and older men who smoke and have obesity are most at risk. Even though the use of continuous positive airway pressure (CPAP) during sleep remains the gold standard treatment, various rehabilitation methods, such as exercise, respiratory therapy, myofunctional therapy, and nutritional lifestyle interventions, also appear to be effective. Moreover, it is increasingly recommended to use alternative or additional therapy options in combination with CPAP therapy.

OBJECTIVE

This study aims to evaluate if a comprehensive home-based, remotely supervised rehabilitation program (tele-RHB), in combination with standard therapy, can improve OSA severity by decreasing the apnea-hypopnea index (AHI); improve objective parameters of polysomnographic, spirometric, anthropometric, and body composition examinations; improve lipid profile, maximal mouth pressure, and functional capacity tests; and enhance the subjective perception of QoL, as well as daytime sleepiness in male participants with moderate to severe OSA. Our hypothesis is that a combination of the tele-RHB program and CPAP therapy will be more effective by improving OSA severity and the abovementioned parameters.

METHODS

This randomized controlled trial aims to recruit 50 male participants between the ages of 30 and 60 years with newly diagnosed moderate to severe OSA. Participants will be randomized 1:1, either to a 12-week tele-RHB program along with CPAP therapy or to CPAP therapy alone. After the completion of the intervention, the participants will be invited to complete a 1-year follow-up. The primary outcomes will be the polysomnographic value of AHI, Epworth Sleepiness Scale score, 36-Item Short Form Health Survey (SF-36) score, percentage of body fat, 6-minute walk test distance covered, as well as maximal inspiratory and expiratory mouth pressure values. Secondary outcomes will include polysomnographic values of oxygen desaturation index, supine AHI, total sleep time, average heart rate, mean oxygen saturation, and the percentage of time with oxygen saturation below 90%; anthropometric measurements of neck, waist, and hip circumference; BMI values; forced vital capacity; forced expiratory volume in 1 second; World Health Organization's tool to measure QoL (WHOQOL-BREF) score; and lipid profile values.

RESULTS

Study recruitment began on October 25, 2021, and the estimated study completion date is December 2024. Analyses will be performed to examine whether the combination of the tele-RHB program and CPAP therapy will be more effective in the reduction of OSA severity and improvement of QoL, body composition and circumferences, exercise tolerance, lipid profile, as well as respiratory muscle and lung function, compared to CPAP therapy alone.

CONCLUSIONS

The study will evaluate the effect of a comprehensive tele-RHB program on selected parameters mentioned above in male participants. The results of this intervention could help the further development of novel additional therapeutic home-based options for OSA.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04759456; https://clinicaltrials.gov/ct2/show/NCT04759456.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/47460.

The Usefulness of Questionnaires in Assessing the Risk of Obstructive Sleep Apnea in Patients in the Managed Care after Acute Myocardial Infarction Program-The Results of a Cross-Sectional Study

Obstructive sleep apnea (OSA) worsens prognosis after myocardial infarction (MI) but often remains undiagnosed. The study aimed to evaluate the usefulness of questionnaires in assessing the risk of OSA in patients participating in managed care after an acute myocardial infarction program. Study group: 438 patients (349 (79.7%) men) aged 59.92 ± 10.92, hospitalized in the day treatment cardiac rehabilitation department 7-28 days after MI. OSA risk assessment: A 4-variable screening tool (4-V), STOP-BANG questionnaire, Epworth sleepiness scale (ESS), and adjusted neck circumference (ANC). The home sleep apnea testing (HSAT) was performed on 275 participants. Based on four scales, a high risk of OSA was found in 283 (64.6%) responders, including 248 (56.6%) based on STOP-BANG, 163 (37.5%) based on ANC, 115 (26.3%) based on 4-V, and 45 (10.3%) based on ESS. OSA was confirmed in 186 (68.0%) participants: mild in 85 (30.9%), moderate in 53 (19.3%), and severe in 48 (17.5%). The questionnaires' sensitivity and specificity in predicting moderate-to-severe OSA were: for STOP-BANG-79.21% (95% confidence interval; CI 70.0-86.6) and 35.67% (95% CI 28.2-43.7); ANC-61.39% (95% CI 51.2-70.9) and 61.15% (95% CI 53.1-68.8); 4-V-45.54% (95% CI 35.6-55.8) and 68.79% (95% CI 60.9-75.9); ESS-16.83% (95% CI 10.1-25.6) and 87.90% (95% CI 81.7-92.6). OSA is common in post-MI patients. The ANC most accurately estimates the risk of OSA eligible for positive airway pressure therapy. The sensitivity of the ESS in the post-MI population is insufficient and limits this scale's usefulness in risk assessment and qualification for treatment.

Prevalence, Impact, and Trajectories of Sleep Disturbance in Cardiac Rehabilitation: A NARRATIVE REVIEW AND SUGGESTIONS FOR EVALUATION AND TREATMENT

OBJECTIVE

The aim of this review was to summarize literature examining the prevalence, impact, and trajectories of sleep disturbance in cardiac rehabilitation (CR) patients and discuss how CR programs may incorporate targeted evaluation and interventions to promote sleep health.

REVIEW METHODS

A narrative review of literature allowed for an examination of the prevalence of sleep disturbance in CR patients, the effects of sleep disturbance on CR outcomes, and trajectories of sleep disturbance in CR.

SUMMARY

Sleep disturbance is prevalent in CR patient populations and is related to clinical and functional outcomes. Sleep may be an important biobehavioral process to target in CR to improve important patient outcomes and achieve secondary prevention goals.

Resistance Training of Inspiratory Muscles After Coronary Artery Disease May Improve Obstructive Sleep Apnea in Outpatient Cardiac Rehabilitation: RICAOS Study

Background

Obstructive sleep apnea (OSA) affects 5% of the adult population and its prevalence is up to 13 times higher in coronary artery disease (CAD) patients. However, OSA in this population is less symptomatic, leading to lower adherence to positive airway pressure (CPAP). While oropharyngeal exercise showed a significant decrease in apnea-hypopnea index (AHI) in patients with moderate OSA, there have been no studies testing the impact of specific inspiratory muscle training (IMT) for these patients. The aim of our study was to assess the effectiveness of IMT on AHI reduction in CAD patients with moderate OSA.

Methods

We included patients with CAD involved in a cardiac rehabilitation program and presenting an AHI between 15 and 30. Patients were randomized in a 1:1 allocation to a control group (CTL – classic training) or an IMT group (classic training + IMT). IMT consisted in 60 deep inspirations a day, 6 days a week, into a resistive load device set at 70% of the maximum inspiratory pressure (MIP). After 6 weeks, we compared AHI, neck circumference, Epworth Sleepiness Scale, Pittsburgh Sleep Quality index, and quality of life with the 12-item Short Form Survey before and after rehabilitation.

Results

We studied 45 patient (60 ± 9 y, BMI = 27 ± 6 kg.m⁻²). The IMT group (n = 22) significantly improved MIP ( p < 0.05) and had a significant decrease in AHI by 25% (−6.5 ± 9.5, p = 0.02). In the CTL group (n = 23), AHI decreased only by 3.5% (−0.7 ± 13.1; p = 0.29). Between groups, we found a significant improvement in MIP ( p = 0.003) and neck circumference ( p = 0.01) in favor of the IMT group. However, we did not find any significant improvement of AHI in the IMT group compared to CTL ( p = 0.09).

Conclusion

A specific IMT during cardiac rehabilitation contributes to reduce significantly AHI in CAD patients with moderate OSA. Magnitude of the decrease in OSA severity could be enhanced according to implementation of specific IMT in this population.

The beneficial impact of cardiac rehabilitation on obstructive sleep apnea in patients with coronary artery disease

STUDY OBJECTIVES

To assess the impact of cardiac rehabilitation for decreasing sleep-disordered breathing in patients with coronary artery disease.

METHODS

The study included 121 patients aged 60.01 ± 10.08 years, 101 of whom were men, with an increased pretest probability of OSA. The cardiac rehabilitation program lasted 21-25 days. The improvement in cardiorespiratory fitness was assessed using the changes in peak metabolic equivalents, the maximal heart rate achieved, the proportion of the age- and sex-predicted maximal heart rate, and the Six-Minute Walk Test distance. Level 3 portable sleep tests with respiratory event index assessments were performed in 113 patients on admission and discharge.

RESULTS

Increases were achieved in metabolic equivalents (Δ1.20; 95% confidence interval [CI], 0.95-1.40; P < .0001), maximal heart rate (-Δ7.5 beats per minute; 95% CI, 5.00-10.50; P < .0001), proportion of age- and sex-predicted maximal heart rate (Δ5.50%; 95% CI, 4.00-7.50; P < .0001), and the Six-Minute Walk Test distance (Δ91.00 m; 95% CI, 62.50-120.00; P < .0001). Sleep-disordered breathing was diagnosed in 94 (83.19%) patients: moderate in 28 (24.8%) patients and severe in 27 (23.9%) patients, with a respiratory event index of 19.75 (interquartile range, 17.20-24.00) and 47.50 (interquartile range, 35.96-56.78), respectively. OSA was dominant in 90.40% of patients. The respiratory event index reduction achieved in the sleep-disordered breathing group was -Δ3.65 (95% CI, -6.30 to -1.25; P = .003) and was in parallel to the improvement in cardiorespiratory fitness in the subgroups with the highest effort load and with severe sleep-disordered breathing: -Δ6.40 (95% CI, -11.40 to -1.90; P = .03) and -Δ11.00 (95% CI, -18.65 to -4.40; P = .003), respectively.

CONCLUSIONS

High-intensity exercise training during cardiac rehabilitation resulted in a significant decrease in OSA, when severe, in parallel with an improvement in cardiorespiratory fitness in patients with coronary artery disease.

Prevalence of obstructive sleep apnoea in acute coronary syndrome patients: systematic review and meta-analysis

Background

Obstructive Sleep Apnoea (OSA) has been recognised as a risk factor for cardiovascular diseases such as hypertension and cardiovascular events such as acute coronary syndrome (ACS). Since it is also known to reduce exercise tolerance, it is important to establish the prevalence of OSA in ACS patients, particularly in those who are commencing cardiac rehabilitation (CR) programs.

Methods

Using PRISMA guidelines a systematic search was conducted in order to identify studies that objectively measured (using polysomnography or portable monitoring) the prevalence of OSA in ACS patients following hospital admission. A data extraction table was used to summarise study characteristics and the quality of studies were independently assessed using the Joanna Briggs Institute Prevalence Critical Appraisal Tool. Meta-analysis of the selected studies was conducted in order to estimate OSA prevalence as a function of the two main methods of measurement, the severity of OSA, and timing of the OSA assessment following ACS hospital admission.

Results

Pooled prevalence estimates of OSA using the “gold standard” polysomnography ranged from 22% for severe OSA to 70% for mild OSA, at any time after hospital admission. Similar prevalence estimates were obtained using portable monitoring, but interpretation of these results are limited by the significant heterogeneity observed among these studies.

Conclusions

Prevalence of OSA following ACS is high and likely to be problematic upon patient entry into CR programs. Routine screening for OSA upon program entry may be necessary to optimise effectiveness of CR for these patients.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

This comprehensive review of the 2018 dental literature is provided to inform busy dentists about progress in the profession. Developed by the Committee on Scientific Investigation of the American Academy of Restorative Dentistry, each author brings discipline-specific expertise to one of the 8 sections of the report including (1) prosthodontics; (2) periodontics, alveolar bone, and peri-implant tissues; (3) implant dentistry; (4) dental materials and therapeutics; (5) occlusion and temporomandibular disorders; (6) sleep-related breathing disorders; (7) oral medicine and oral and maxillofacial surgery; and (8) dental caries and cariology. The report targets important information that will likely influence day-to-day treatment decisions. Each review is not intended to stand alone but to update interested readers so that they may visit source materials if greater detail is desired. As the profession continues its march toward evidence-based clinical decision-making, an already voluminous library of potentially valuable dental literature continues to grow. It is the intention of this review and its authors to provide assistance in navigating the extensive dental literature published in 2018. It is our hope that readers find this work useful in the clinical management of patients moving forward.