Effect of Obstructive Sleep Apnea in Acute Coronary Syndrome

Effects of continuous positive airway pressure on cardiac events and metabolic components in patients with moderate to severe obstructive sleep apnea and coronary artery disease: a meta-analysis

STUDY OBJECTIVES

This meta-analysis aimed to systematically assess the effects of continuous positive airway pressure (CPAP) in secondary prevention of major cardiovascular events (MACEs) in patients with moderate-to-severe obstructive sleep apnea and coronary artery disease.

METHODS

PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov were searched for observational studies and randomized controlled trials that compared CPAP with usual care in patients with moderate-to-severe obstructive sleep apnea with coronary artery disease. The primary outcomes were MACEs, all-cause death, acute coronary syndrome, rehospitalization for heart failure, repeat revascularization, and arrhythmia.

RESULTS

A total of 11 studies (5 randomized controlled trials and 6 observational studies) with 5,410 patients reported outcomes of MACEs. Treatment with CPAP was associated with a modest risk reduction in MACEs (risk ratio [RR] 0.87, 95% confidence interval [CI] 0.78 to 0.98; P = .02). Similarly, CPAP significantly reduced the risk of all-cause and cardiovascular death by 23% (RR 0.77, 95% CI 0.60 to 0.99; P = .04; I2 = 0%). Subgroup analysis revealed that CPAP adherence time ≥ 4 hours/night had a greater benefit on MACEs by 42% (RR 0.58, 95% CI 0.42 to 0.79; P < .001; I2 = 0%) and repeat revascularization by 44% (RR 0.56, 95% CI 0.34 to 0.92; P = .02; I2 = 0%). Also, CPAP had a positive effect on systolic and diastolic blood pressure.

CONCLUSIONS

CPAP therapy might prevent subsequent MACEs and all-cause death among patients with moderate to severe obstructive sleep apnea and concomitant coronary artery disease. CPAP use exceeding 4 hours/night may add more benefits on MACEs, repeat revascularization, and blood pressure.

CLINICAL TRIAL REGISTRATION

Registry: PROSPERO database; Name: Effects of Continuous Positive Airway Pressure on Cardiovascular Events and Metabolic Components in Patients with Obstructive Sleep Apnea and Coronary Artery Disease; URL: https://www.crd.york.ac.uk/prospero/display_record.php?ID= CRD42020213546; Identifier: CRD42020213546.

CITATION

Yang D, Li L, Dong J, Yang W, Liu Z. Effects of continuous positive airway pressure on cardiac events and metabolic components in patients with moderate to severe obstructive sleep apnea and coronary artery disease: a meta-analysis. J Clin Sleep Med. 2023;19(12):2015-2025.

Sex-Specific Associations of Obstructive Sleep Apnea Risk With Patient Characteristics and Functional Outcomes After Acute Myocardial Infarction: Evidence From the VIRGO Study

Background Though associations between obstructive sleep apnea (OSA) and cardiovascular outcomes are well described, limited data exist regarding the impact of OSA on sex-specific outcomes after acute myocardial infarction (AMI). Methods and Results The VIRGO (Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients) study enrolled 3572 adults aged 18 to 55 years with AMI from the United States and Spain during 2008 to 2012. We included patients for whom the Berlin Questionnaire for OSA was scored at the time of AMI admission (3141; 2105 women, 1036 men). We examined the sex-specific association between baseline OSA risk with functional outcomes including health status and depressive symptoms at 1 and 12 months after AMI. Among both groups, 49% of patients were at high risk for OSA (1040 women; 509 men), but only 4.7% (148) of patients had a diagnosed history of OSA. Though patients with a high OSA risk reported worse physical and mental health status and depression than low-risk patients in both sexes, the difference in these functional outcomes was wider in women than men. Moreover, women with a high OSA risk had worse health status, depression, and quality of life than high-risk men, both at baseline and at 1 and 12 months after AMI. Conclusions Young women with a high OSA risk have poorer health status and more depressive symptoms than men at the time of AMI, which may place them at higher risk of poorer health outcomes over the year following the AMI. Further, the majority of patients at high risk of OSA are undiagnosed at the time of presentation of AMI.

High prevalence of sleep-disordered breathing in the intensive care unit - a cross-sectional study

PURPOSE

Sleep-disordered breathing may be induced by, exacerbate, or complicate recovery from critical illness. Disordered breathing during sleep, which itself is often fragmented, can go unrecognized in the intensive care unit (ICU). The objective of this study was to investigate the prevalence, severity, and risk factors of sleep-disordered breathing in ICU patients using a single respiratory belt and oxygen saturation signals.

METHODS

Patients in three ICUs at Massachusetts General Hospital wore a thoracic respiratory effort belt as part of a clinical trial for up to 7 days and nights. Using a previously developed machine learning algorithm, we processed respiratory and oximetry signals to measure the 3% apnea-hypopnea index (AHI) and estimate AH-specific hypoxic burden and periodic breathing. We trained models to predict AHI categories for 12-h segments from risk factors, including admission variables and bio-signals data, available at the start of these segments.

RESULTS

Of 129 patients, 68% had an AHI ≥ 5; 40% an AHI > 15, and 19% had an AHI > 30 while critically ill. Median [interquartile range] hypoxic burden was 2.8 [0.5, 9.8] at night and 4.2 [1.0, 13.7] %min/h during the day. Of patients with AHI ≥ 5, 26% had periodic breathing. Performance of predicting AHI-categories from risk factors was poor.

CONCLUSIONS

Sleep-disordered breathing and sleep apnea events while in the ICU are common and are associated with substantial burden of hypoxia and periodic breathing. Detection is feasible using limited bio-signals, such as respiratory effort and SpO2 signals, while risk factors were insufficient to predict AHI severity.

Obstructive sleep apnea and cardiovascular events in acute coronary syndrome: a meta-analysis

OBJECTIVE

Obstructive sleep apnea (OSA) in patients with the acute coronary syndrome (ACS) were at high risk for cardiovascular events, but the results are currently inconclusive. We aimed to conduct a systematic review to determine the incidence of cardiovascular events among ACS patients with OSA by a meta-analysis of observational studies.

METHODS

PubMed, Embase, and Cochrane Library were searched for studies related to the association between OSA and the risk of cardiovascular events in patients with ACS. Risk of bias in observational studies was assessed according to the Risk Of Bias In the Non-randomized Studies-Of Interventions tool.We performed a meta-analysis using a random-effects model to calculate estimates of pooled hazard ratios (HR) with 95% confidence intervals (CI), and heterogeneity was assessed using the statistics.

RESULTS

A total of 12 studies evaluating ACS patients with OSA were included in the meta-analysis. OSA was related to the increased risk of MACE (HR = 2.2; 95% CI, 1.274-3.805, I2  = 76.1%). The effect of OSA on MACCE (HR = 1.921; 95% CI, 1.45-2.546; I2  = 19.1%) and readmission for unstable angina (HR = 3.137, 95% CI, 1.06-9.283; I2  = 52.4%) were statistically significant in the pooled analysis. All of the outcomes in the included studies had a serious risk of bias and the Grading of Recommendation, Assessment, Development, and Evaluation evidence level of all the evaluation results were very low.

CONCLUSIONS

OSA was associated with a significant increase in the risk of cardiovascular events for patients with ACS. Additional randomized controlled trial studies are required to confirm the results and to prove the treatment of OSA can change the prognosis.

Prognostic Implications of OSA in Acute Coronary Syndrome by Obesity Status

BACKGROUND

A close relationship exists between OSA and obesity. The impact of obesity on the prognostic significance of OSA in patients with acute coronary syndrome (ACS) remains unclear.

RESEARCH QUESTION

Do the effects of OSA on subsequent cardiovascular events in patients with ACS vary with obesity status?

STUDY DESIGN AND METHODS

This is a prospective cohort study. Patients 18 to 85 years of age and hospitalized for ACS were consecutively enrolled and underwent portable sleep monitoring after clinical stabilization. OSA was defined as an apnea hypopnea index ≥ 15 events/h. The primary end point was major adverse cardiovascular and cerebrovascular event (MACCE), including cardiovascular death, hospitalization for ACS, stroke, ischemia-driven revascularization, or hospitalization for heart failure.

RESULTS

Among 1,920 patients enrolled (84.5% men; mean age ± SD, 56.4 ± 10.5 years), 1,013 (52.8%) had OSA, and 718 (37.4%) were obese (BMI ≥ 28 kg/m²). During 2.9 years (1.5, 3.6) follow up, the incidence of MACCE was significantly higher in patients with obesity than in patients without obesity (hazard ratio [HR], 1.29; 95% CI, 1.06-1.58; P = .013). Although the prevalence of OSA was lower in patients without obesity than in those with obesity (43.9% vs 67.5%, P < .001), OSA independently predicted the incidence of MACCE only in patients without obesity (adjusted HR, 1.34; 95% CI, 1.03-1.75; P = .03), but not in patients with obesity (adjusted HR, 1.10; 95% CI, 0.78-1.55; P = .58). No significant interaction between obesity and OSA was noted (P for interaction = .35). The incremental risk associated with OSA in patients without obesity might be explained by more hospitalization for ACS and ischemia-driven revascularization.

INTERPRETATION

For patients with ACS, OSA was independently associated with an increased risk of subsequent events, particularly among patients without obesity. These findings highlight the importance of identifying OSA in nonobese patients with ACS.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT03362385; URL: www.

CLINICALTRIALS

gov.

A systematic review on the association of sleep-disordered breathing with cardiovascular pathology in adults

Sleep-disordered breathing (SDB) is characterized by repeated breathing pauses during sleep. The prevalence of SDB varies widely between studies. Some longitudinal studies have found an association of SDB with incident or recurrent cardiovascular events. We sought to systematically describe the current data on the correlation between SDB and cardiovascular pathology. Studies were included if they were original observational population-based studies in adults with clearly diagnosed SDB. The primary outcomes include all types of cardiovascular pathology. We carried out pooled analyses using a random effects model. Our systematic review was performed according to the PRISMA and MOOSE guidelines for systematic reviews and was registered with PROSPERO. In total, 2652 articles were detected in the databases, of which 76 articles were chosen for full-text review. Fourteen studies were focused on samples of an unselected population, and 8 studies were focused on a group of persons at risk for SDB. In 5 studies, the incidence of cardiovascular pathology in the population with SDB was examined. In total, 49 studies described SDB in patients with cardiovascular pathology. We found an association between SDB and prevalent /incident cardiovascular disease (pooled OR 1.76; 95% CI 1.38–2.26), and pooled HR (95% CI 1.78; 95% CI 1.34–2.45). Notably, in patients with existing SDB, the risk of new adverse cardiovascular events was high. However, the relationship between cardiovascular disease and SDB is likely to be bidirectional. Thus, more large-scale studies are needed to better understand this association and to decide whether screening for possible SDB in cardiovascular patients is reasonable and clinically significant.

Prevalence of obstructive sleep apnoea among patients admitted with acute coronary syndrome in a hill state of northern India

Background Obstructive sleep apnoea (OSA) is one of the emerging non-traditional cardiovascular risk factors. Studying OSA may contribute towards a better understanding of current concepts of atherogenesis and in guiding therapy. Methods We conducted this cross-sectional study among 66 patients with acute coronary syndrome (ACS) in a tertiary care hospital from 1 January 2019 to 30 June 2020. We included patients of ST elevation myocardial infarction (STEMI)/ non-STEMI (on achieving Killip class I/II) and unstable angina and performed in-hospital overnight polysomnography (PSG) within 8 weeks of index event. Apnoea-hypoapnoea index (AHI) value 5-<15 was defined as mild OSA, AHI 15-<30 as moderate OSA and AHI >30 as severe OSA. We analysed data using Epi Info version 7.2.4 for Windows. Results The 66 patients had a mean (SD) age of 57.7 (11.1) years and 54 (81.8%) were men. Forty-three (65.1%) patients had STEMI, 19 (28.7%) had non-STEMI and 4 (6%) had unstable angina. On PSG, the prevalence of OSA (AHI>5) was 78.8% (95% CI 67.0-87.9). Of these, AHI >15 was significantly associated with diabetes, hypertension and different measures of obesity (p<0.05). Conclusions This study, conducted in a hill state of northern India, showed a high prevalence of OSA in patients with ACS. Obesity, diabetes mellitus and hypertension were significantly associated with severity of OSA (AHI>15).

Does continuous positive airway pressure therapy benefit patients with coronary artery disease and obstructive sleep apnea? A systematic review and meta-analysis

The prevalent co‐morbidity of coronary artery disease (CAD) and obstructive sleep apnea (OSA) has attracted great interest. However, effects of continuous positive airway pressure (CPAP) in patients with OSA and CAD for cardiovascular outcomes and deaths are still controversial. Usage of CPAP among patients with CAD and OSA could decrease the risk of cardiovascular events and death in adults. PubMed, EMBASE, Web of science, and Cochrane Library were systematically searched. Studies that described association of CPAP treatment with cardiovascular events in CAD and OSA patients were included. The main outcome was the major adverse cardiovascular events (MACE), including all‐cause death, cardiovascular death, myocardial infarction (MI), stroke, and repeat revascularization. Summary relative risks (risk ratios [RRs]) and 95% confidence intervals (CIs) of outcomes were pooled and heterogeneity was assessed with the I² statistic. Nine studies enrolling 2590 participants with OSA and CAD were included and extracted data. There was significant association of CPAP with reduced risk of MACE (RR, 0.73, 95% CI [0.55, 0.96]), particularly among those with AHI less than 30 events/h (RR, 0.43, 95% CI [0.22, 0.84]). Similarly, the same result was found in all‐cause death (RR, 0.66, 95% CI, [0.46, 0.94]) and cardiovascular death (RR, 0.495, 95% CI [0.292, 0.838]). Our data suggested that CPAP usage, compared to usual care, was associated with reduced risks of cardiovascular outcomes or death in patients with OSA and CAD, particularly in the subgroup with AHI less than 30 events/h, which still needs further studies to confirm.

Association between triglyceride glucose index and obstructive sleep apnea risk in Korean adults: a cross-sectional cohort study

Background

Triglyceride glucose (TyG) index is a reliable marker of insulin resistance, which is linked to obstructive sleep apnea (OSA). However, the relationship between TyG index and OSA has not been adequately assessed. This study aimed to evaluate the association between TyG index and OSA.

Methods

TyG index was assessed in 180 (mean age: 48.6 ± 13.8 years; 73.9% male) consecutive Korean adults with suspected OSA admitted to the sleep clinic at St. Paul’s Hospital between 2010 and 2012. The occurrence of more than 5 apnea-hypopnea index (AHI) events/h was used to define OSA. TyG index was calculated using the following equation: In [fasting triglycerides (mg/dL) × fasting glucose (mg/dL)/2]. All participants were grouped according to TyG index tertiles. Multivariate logistic regression analysis was used to determine factors associated with increased OSA risk.

Results

The overall prevalence of OSA in study participants was determined to be 83.9%. The prevalence of OSA increased (I [lowest]: 71.6%; II: 88.7%; III [highest]: 91.4%), and lowest peripheral oxygen saturation (SpO₂) levels decreased (I: 83.3 ± 8.5%; II: 79.9 ± 8.7%; III: 79.0 ± 8.3%), as TyG index tertile increased (P < 0.05). TyG index was correlated with AHI (r = 0.179) and lowest SpO₂ (r = − 0.188) (P < 0.05, respectively). Univariate linear regression analysis revealed an association between TyG and AHI (β = 10.084; P = 0.016). Multivariate logistic regression analysis showed that TyG index (odds ratio [OR]: 3.348; 95% confidence interval [CI]: 1.081–10.372), age ≥ 55 years (OR: 5.426; 95% CI: 1.642–17.935), and obesity (OR: 3.801; 95% CI: 1.468–9.842) were associated with increased OSA risk (all P < 0.05). The optimal TyG index cut-off value for predicting OSA was 8.83 (sensitivity: 61.6%; specificity: 69.0%; area under the curve: 0.688; P = 0.001). The predictive value of the OSA cut-off value improved when age ≥ 55 years and obesity were considered.

Conclusion

Increased TyG index was independently associated with increased OSA risk.

The relationship of obstructive sleep apnea and cardiovascular diseases from the perspective of evidence-based medicine. Part 1

The results of prospective studies, meta-analyzes and systematic reviews on the associations of obstructive sleep apnea (OSA) with various cardiovascular diseases (CVD) were analyzed. Currently, the mechanisms related to high prevalence of breathing-related sleep disorders among population of economically developed countries are clear, and an increase in the number of OSA patients has been shown. The relationship between OSA and CVD has been widely confirmed in large cohort studies. The first review part discusses the relationship of hypertension (HTN) and various heart arrhythmias (atrial fibrillation (AF), bradyarrhythmias, premature ventricular contraction, sudden death during sleep) with breathing-related sleep disorders. These groups of cardiovascular disorders currently show the most proven relationship with sleep apnea. In addition to cross-sectional studies indicating the high prevalence of OSA in patients with HTN and AF, some observational studies indicate an increase in the number of patients with HTN and paroxysmal AF with history of untreated sleep apnea. An analysis of the current issues of OSA phenotypes (in particular, REM-related OSA in hypertensive patients) as the most unfavorable cardiovascular factors is carried out.

Relation of Age to Survival in Patients with Obstructive Sleep Apnea who Develop an Acute Coronary Event (from the National Inpatient Sample)

This study was undertaken to investigate whether obstructive sleep apnea (OSA) produces a survival advantage in acute coronary syndrome (ACS), and to evaluate the mechanism of any benefit, including the impact of age and other risk factors. The National Inpatient Sample was queried for all patients who were admitted for ACS during the years 2013 to 2014. The primary outcomes were all-cause in-hospital mortality and cardiogenic shock (CS). Multivariable logistic regression was used for analysis. A total of 1,080,340 patients with ACS were included, 63,255 patients had OSA. The majority of patients were males (60.3%) and of Caucasian race (75%). The mean age was 67 years (SEM: 0.1). Despite a higher burden of risk factors and older age, OSA patients had a lower risk for mortality and cardiogenic shock adjusted OR 0.68 (95%CI 0.61-0.75), p <0.001 and 0.81 (95%CI: 0.74 to 0.89), p <0.001 respectively. Age was an important effect modifier. Survival advantage and lower risk for CS arises at the age above 55 and become more apparent with increasing age. In conclusion, despite a higher CV risk profile, and older age, OSA produces a survival benefit in ACS. Age is a significant modifier of risk in OSA patients with ACS. Ischemic preconditioning might explain these results.

Prevalence of Undiagnosed Obstructive Sleep Apnea Among Patients Hospitalized for Cardiovascular Disease and Associated In-Hospital Outcomes: A Scoping Review

BACKGROUND

Obstructive sleep apnea (OSA) is associated with long-term cardiovascular morbidity and is highly prevalent in patients with cardiovascular disease (CVD). The objectives of this scoping review were to determine the prevalence of OSA inpatients hospitalized for CVD and to map the range of in-hospital outcomes associated with OSA.

METHODS

We searched MEDLINE(R), Embase, and Cochrane Databases for articles published from 1946-2018. We included studies involving non-surgical adults with OSA or at high risk of OSA who were hospitalized for CVD. The outcomes were considered as in-hospital if they were collected from admission up to 30 days post-discharge from hospital.

RESULTS

After the screening of 4642 articles, 26 studies were included for qualitative synthesis. Eligible studies included patients presenting with acute coronary syndromes (n = 19), congestive heart failure (n = 6), or any cardiovascular disease (n = 1). The pooled prevalence of OSA in cardiac inpatients was 48% (95% CI: 42-53). The in-hospital outcomes reported were mortality (n = 4), length of stay (n = 8), left ventricular ejection fraction (n = 8), peak troponin (n = 7), peak B-type natriuretic peptide (n = 4), and composite cardiovascular complications (n = 2).

CONCLUSIONS

OSA is highly prevalent in the cardiac inpatient population. The outcomes reported included mortality, cardiac function, cardiac biomarkers, and resource utilization. There are significant knowledge gaps regarding the effect of treatment and OSA severity on these outcomes. The findings from this review serve to inform further areas of research on the management of OSA among patients with CVD.

Obstructive Sleep Apnea during REM Sleep and Cardiovascular Disease

RATIONALE

Obstructive sleep apnea (OSA) during REM sleep is a common disorder. Data on whether OSA that occurs predominantly during REM sleep is associated with health outcomes are limited.

OBJECTIVES

The present study examined the association between OSA during REM sleep and a composite cardiovascular endpoint in a community sample with and without prevalent cardiovascular disease.

METHODS

Full-montage home polysomnography was conducted as part of the Sleep Heart Health Study. The study cohort was followed for an average of 9.5 years, during which time cardiovascular events were assessed. Only participants with a non-REM apnea-hypopnea index (AHI) of less than 5 events/h were included. A composite cardiovascular endpoint was determined as the occurrence of nonfatal or fatal events, including myocardial infarction, coronary artery revascularization, congestive heart failure, and stroke. Proportional hazards regression was used to derive the adjusted hazards ratios for the composite cardiovascular endpoint.

MEASUREMENTS AND MAIN RESULTS

The sample consisted of 3,265 subjects with a non-REM AHI of less than 5.0 events/h. Using a REM AHI of less than 5.0 events/h as the reference group (n = 1,758), the adjusted hazards ratios for the composite cardiovascular endpoint in those with severe REM OSA (≥30 events/h; n = 180) was 1.35 (95% confidence interval, 0.98-1.85). Stratified analyses demonstrated that the association was most notable in those with prevalent cardiovascular disease and severe OSA during REM sleep with an adjusted hazards ratio of 2.56 (95% confidence interval, 1.46-4.47).

CONCLUSIONS

Severe OSA that occurs primarily during REM sleep is associated with higher incidence of a composite cardiovascular endpoint, but in only those with prevalent cardiovascular disease.

Screening for obstructive sleep apnea among patients undergoing coronary catheterization in Jordan

Aims: This study aimed to utilize a validated sleep questionnaire as a screening tool for symptoms and risk of obstructive sleep apnea in patients undergoing coronary catheterization in Jordan.

Materials and methods: A cross-sectional design was used to screen adult patients undergoing coronary catheterization for obstructive sleep apnea (OSA). The Berlin sleep questionnaire was used to record nocturnal and daytime symptoms of OSA and to stratify patients into “low-risk” or “high-risk” for OSA. Coronary artery disease was defined as ≥50% intraluminal stenosis in at least one coronary vessel.

Results: A total of 398 patients were studied, mean age was 58.7 years (SD=10.70), ranging from 21–92 years, and 68.6% were males. Based on the Berlin sleep questionnaire’s definition, 176 patients (44.2%) were at high-risk for obstructive sleep apnea. Snoring was reported by 61%; loud in 42.1%, and frequent in 62%. Daytime sleepiness was reported by 36%, and 18.9% had fallen asleep while driving. Witnessed apnea during sleep was less reported (7.8%). Prevalence of symptoms and risk of OSA were not different between patients with and without coronary artery disease, P>0.05. In addition, logistic regression indicated that there was no significant association between risk of OSA and coronary artery disease, adjusted (odds ratio=0.93, 95% Confidence Interval=0.60–1.44, P=0.752).

Conclusions: Symptoms and risk of obstructive sleep apnea were common among adult Jordanians undergoing coronary catheterization. There was no association between risk of obstructive sleep apnea and coronary artery disease. Larger studies are needed to assess the role of screening for obstructive sleep apnea in this patient population.

Upper Airway Video Endoscopy: Assessment of the response to positive pressure ventilation and mechanical in-exsufflation

Upper airways (UA) include the nasal cavities, pharynx, and larynx, and its main function is to warm and filter the inspired air. UA dysfunction is in the pathogenesis of various disorders, such as obstructive sleep apnea syndrome (OSAS) and vocal cord dysfunction. In addition, in some neurodegenerative diseases (e.g. Amyotrophic Lateral Sclerosis - ALS), UA dysfunction may also compromise the effective use of ventilatory support (VS). In this context, the endoscopic evaluation of UA may be useful in understanding the OSAS mechanisms, in determining the causes for treatment-induced airway obstruction and even in helping to titrate noninvasive ventilation (NIV) in ALS patients with bulbar or pseudo-bulbar (spastic) dysfunction. Specifically, in OSAS patients, when residual obstructive events persist, although an optimal ventilatory mode has been apparently achieved, along with interface and equipment, the endoscopic evaluation of UA seems to be a valuable tool in understanding its mechanisms, even assisting adjustments to NIV parameters. In addition, it has also been described as being useful in laryngeal response to mechanical in-exsufflation (MI-E) and Exercise-Induced Laryngeal Obstruction (EILO). However, no protocol has yet been published or validated for this. For this reason, a literature review was conducted on UA function and its response to positive pressure and MI-E. Special emphasis has also been given to the current indication for video endoscopy in chronically ventilated patients.

Obstructive sleep apnoea and comorbidity - an overview of the association and impact of continuous positive airway pressure therapy

INTRODUCTION

Obstructive sleep apnoea (OSA) is highly prevalent and there is considerable evidence supporting an independent association with a wide range of co-morbidities including cardiovascular, endocrine and metabolic, neuropsychiatric, pulmonary, and renal. Areas covered: A PubMed search of all the recent literature relating to OSA and co-morbidities was undertaken to critically evaluate the potential relationships and possible benefit of continuous positive airway pressure (CPAP) therapy. Expert commentary: The evidence supporting an independent association is stronger for some co-morbidities than others and in cardiovascular diseases is strongest for hypertension and atrial fibrillation. Potential mechanisms include intermittent hypoxia, fluctuating intrathoracic pressure, and recurring micro-arousals that trigger cell and molecular consequences including sympathetic excitation, systemic inflammation and oxidative stress, in addition to metabolic and endothelial dysfunction. Different mechanisms may predominate in individual co-morbidities. Recent long term randomised controlled trials have cast doubt on benefits to co-morbidities from CPAP therapy of OSA, especially where co-morbidities are already established. However, benefits may result in patients who are compliant with therapy and further research is required to clearly establish the role of OSA therapy in both primary and secondary prevention of co-morbidities.

Timely diagnosis and treatment of sleep apnea reduce cardiovascular sequelae in patients with myocardial infarction

Background

The present study aimed to test if the temporal sequence between sleep apnea (SA) diagnosis and incident myocardial infarction (MI) was associated with the long-term mortality and cardiovascular event in a community-based cohort.

Methods

We retrieved data from 9,453 incident MI patients between Jan. 1^st 2000 and Dec. 31^st 2012 from the Taiwan National Health Insurance Research Database. The study subjects included 207 MI patients with SA (SA-MI), further stratified into 110 with pre-existing SA before MI (SA-bMI) and 96 diagnosed with SA after MI (SA-pMI). The median follow-up period was 4.2 years. Propensity-score-matched controls were selected from 9,246 non-SA MI patients (non-SA-MI). The association of SA and outcomes including all-cause mortality and major adverse cardiac and cerebrovascular events (MACCEs) were analyzed by a Cox proportional hazards model.

Results

The result showed that SA was not associated with mortality regardless of the timing of SA diagnosis. SA-pMI was associated with increased risk of MACCEs (Hazard ratio [HR]: 1.412, 95% confidence interval [CI]: 1.037~1.923, p = 0.029) including re-MI or revascularization and ischemic heart disease hospitalization. Such an association was most significant for SA diagnosed within one year after MI (HR: 2.029, 95% CI: 1.265~3.254, p = 0.003), which was not seen in patients treated with continuous positive airway pressure (CPAP).

Conclusion

The temporal sequence and the time interval between SA diagnosis and incident MI was associated with the cardiovascular events after MI, especially within one year after MI. Early assessment for the presence of SA after incident MI and early CPAP intervention may reduce the risk of further adverse cardiovascular events.

Effect of continuous positive airway pressure on long-term cardiovascular outcomes in patients with coronary artery disease and obstructive sleep apnea: a systematic review and meta-analysis

Background

Obstructive sleep apnea (OSA) is highly prevalent in patients with coronary artery disease (CAD) and is associated with recurrent cardiovascular risk. However, whether treatment with continuous positive airway pressure (CPAP) reduces this risk remains unclear. We performed a systematic review and meta-analysis to assess the effect of CPAP on long-term cardiovascular outcomes in patients with concomitant CAD and OSA.

Methods

We searched the PubMed, EMBASE, and Cochrane library from their inceptions to October 7, 2017. We included observational studies and randomized controlled trials (RCTs) that described the association of CPAP treatment with cardiovascular events in patients with CAD and OSA. The primary outcome of interest was major adverse cardiovascular event (MACE), including all-cause or cardiovascular death, myocardial infarction, stroke, repeat revascularization, or hospitalization for heart failure. Outcomes data were pooled using random effects models and heterogeneity assessed with the I² statistic.

Results

We identified 9 studies (2 RCTs and 7 observational studies) with 1430 participants. The median follow-up duration was from 36 to 86.5 months. Treatment with CPAP was associated with a significantly lower risk of MACE in 6 observational studies (RR 0.61, 95% CI: 0.39–0.94, P = 0.02), but this was not reproduced in 2 RCTs (RR 0.57, 95% CI: 0.32–1.02, P = 0.06). Similarly, CPAP significantly reduced the risk of all-cause death (4 observational studies) and cardiovascular death (3 observational studies), which were also not confirmed in RCTs.

Conclusions

The use of CPAP in patients with CAD and OSA might prevent subsequent cardiovascular events, which was only demonstrated in observational studies, but not in RCTs. The value of CPAP therapy as second prevention for CAD needs further investigation.

Electronic supplementary material

The online version of this article (10.1186/s12931-018-0761-8) contains supplementary material, which is available to authorized users.

Effects of continuous positive airway pressure on anxiety, depression, and major cardiac and cerebro-vascular events in obstructive sleep apnea patients with and without coronary artery disease

Objective:

Obstructive sleep apnea (OSA) is associated with bad cardiovascular outcomes and a high prevalence of anxiety and depression. This study investigated the effects of continuous positive airway pressure (CPAP) on the severity of anxiety and depression in OSA patients with or without coronary artery disease (CAD) and on the rate of cardio- and cerebro-vascular events in those with OSA and CAD.

Materials and Methods:

This prospective study included patients with moderate-to-severe OSA, with or without a recent diagnosis of CAD; all were started on CPAP therapy. Patients completed the Chinese versions of the Beck Anxiety Inventory (BAI) and Beck Depression Inventory-II (BDI-II) at baseline and after 6-month follow-up. The occurrence of major adverse cardiac and cerebrovascular events (MACCE) was assessed every 3 months up to 1 year.

Results:

BAI scores decreased from 8.5 ± 8.4 at baseline to 5.4 ± 6.9 at 6 months in CPAP-compliant OSA patients without CAD (P < 0.05). BAI scores also decreased from 20.7 ± 14.9 to 16.1 ± 14.5 in CPAP-compliant OSA patients with CAD. BDI-II scores decreased in CPAP-compliant OSA patients without CAD (from 11.1 ± 10.7 at baseline to 6.6 ± 9.5 at 6 months) and in CPAP-compliant OSA patients with CAD (from 20.4 ± 14.3 to 15.9 ± 7.3). In addition, there was a large effect size (ES) of BAI and BDI in 6-month CPAP treatment of OSA patients with CAD and a large ES in those with OSA under CPAP treatment. In OSA patients with CAD, the occurrence of MACCE was significantly lower in CPAP-compliant patients than that in CPAP noncompliant patients (11% in CPAP compliant and 50% in noncompliant; P < 0.05).

Conclusions:

CPAP improved anxiety and depression in OSA patients regardless of CAD. In OSA patients with CAD, CPAP-compliant patients had a lower 1-year rate of MACCE than CPAP-noncompliant patients.

Association of obstructive sleep apnoea with the risk of vascular outcomes and all-cause mortality: a meta-analysis

OBJECTIVE

This study aimed to conduct a meta-analysis to explore and summarise the evidence regarding the association between obstructive sleep apnoea (OSA) and the subsequent risk of vascular outcomes and all-cause mortality.

METHODS

Electronic databases PubMed, Embase and the Cochrane Library were searched to identify studies conducted through May 2016. Prospective cohort studies that reported effect estimates with 95% CIs of major adverse cardiac events (MACEs), coronary heart disease (CHD), stroke, cardiac death, all-cause mortality and heart failure for different levels versus the lowest level of OSA were included.

RESULTS

A total of 16 cohort studies reporting data on 24 308 individuals were included. Of these, 11 studies reported healthy participants, and the remaining five studies reported participants with different diseases. Severe OSA was associated with an increased risk of MACEs (relative risk (RR): 2.04; 95% CI 1.56 to 2.66; P<0.001), CHD (RR: 1.63; 95% CI 1.18 to 2.26; P=0.003), stroke (RR: 2.15; 95% CI 1.42 to 3.24; P<0.001), cardiac death (RR: 2.96; 95% CI 1.45 to 6.01; P=0.003) and all-cause mortality (RR: 1.54; 95% CI 1.21 to 1.97; P<0.001). Moderate OSA was also significantly associated with increased risk of MACEs (RR: 1.16; 95% CI 1.01 to 1.33; P=0.034) and CHD (RR: 1.38; 95% CI 1.04 to 1.83; P=0.026). No significant association was found between mild OSA and the risk of vascular outcomes or all-cause mortality (P>0.05). Finally, no evidence of a factor-specific difference in the risk ratio for MACEs among participants with different levels of OSA compared with those with the lowest level of OSA was found.

CONCLUSIONS

Severe and moderate OSAs were associated with an increased risk of vascular outcomes and all-cause mortality. This relationship might differ between genders. Therefore, further large-scale prospective studies are needed to verify this difference.

ECG-derived Cheyne-Stokes respiration and periodic breathing in healthy and hospitalized populations

BACKGROUND

Cheyne-Stokes respiration (CSR) has been investigated primarily in outpatients with heart failure. In this study we compare CSR and periodic breathing (PB) between healthy and cardiac groups.

METHODS

We compared CSR and PB, measured during 24 hr of continuous 12-lead electrocardiographic (ECG) Holter recording, in a group of 90 hospitalized patients presenting to the emergency department with symptoms suggestive of acute coronary syndrome (ACS) to a group of 100 healthy ambulatory participants. We also examined CSR and PB in the 90 patients presenting with ACS symptoms, divided into a group of 39 (43%) with confirmed ACS, and 51 (57%) with a cardiac diagnosis but non-ACS. SuperECG software was used to derive respiration and then calculate CSR and PB episodes from the ECG Holter data. Regression analyses were used to analyze the data. We hypothesized SuperECG software would differentiate between the groups by detecting less CSR and PB in the healthy group than the group of patients presenting to the emergency department with ACS symptoms.

RESULTS

Hospitalized patients with suspected ACS had 7.3 times more CSR episodes and 1.6 times more PB episodes than healthy ambulatory participants. Patients with confirmed ACS had 6.0 times more CSR episodes and 1.3 times more PB episodes than cardiac non-ACS patients.

CONCLUSION

Continuous 12-lead ECG derived CSR and PB appear to differentiate between healthy participants and hospitalized patients.

Acute chest pain fast track at the emergency department: who was misdiagnosed for acute coronary syndrome?

Background

Acute coronary syndrome (ACS) is a commonly treated disease in the emergency department (ED). Acute chest pain is a common presenting symptom of ACS. Acute chest pain fast track (ACPFT) is a triage to cover patients presenting with chest pain with the aims of early detection and treatment for ACS. This study aimed to assess the quality of the ACPFT with the aim of improving the quality of care for ACS patients.

Methods

This study was conducted at the ED in Mahidol University, Bangkok, Thailand. The inclusion criterion was patients presenting with acute chest pain at the ED. We retrospectively reviewed the medical records of all eligible patients. The primary outcomes of this study were to determine time from door to electrocardiogram and time from door to treatment (coronary angiogram with percutaneous coronary intervention or thrombolytic therapy in the case of ST elevation myocardial infarction). The outcome was compared between those who were in and not in the ACPFT.

Results

During the study period, there were 616 eligible patients who were divided into ACPFT (n=352 patients; 57.1%) and non-ACPFT (n=264 patients; 42.9%) groups. In the ACPFT group (n=352), 315 patients (89.5%) received an electrocardiogram within 10 minutes. The final diagnosis of ACS was made in 80 patients (22.7%) in the ACPFT group and 13 patients (4.9%) in the non-ACPFT group (P-value <0.01). After adjustment using multivariate logistic regression analysis, only epigastric pain was independently associated with being in the ACPFT group (adjusted odds ratio of 0.11; 95% confidence interval of 0.02, 0.56).

Conclusion

The ACPFT at the ED facilitated the prompt work-ups and intervention for ACS.

Serum high-density lipoprotein correlates with serum apolipoprotein M and A5 in obstructive sleep apnea hypopnea syndrome

Purpose

The purpose of this study was to investigate the correlation between serum levels of serum apolipoprotein M (ApoM), A5 (ApoA5), and high-density lipoprotein (HDL) in patients with obstructive sleep apnea hypopnea syndrome (OSAHS) and study the effects of nasal continuous positive airway pressure treatment on these serum biomarkers.

Methods

Thirty OSAHS patients and 15 non-OSAHS probands as control were selected for the study. Serum HDL, ApoM, and ApoA5 levels in two groups were detected; differences and association among them were analyzed. Patients with moderate and severe OSAHS underwent 3-month auto-continuous positive airway pressure treatment, and a comparative study was conducted to investigate the changes in blood lipids, serum ApoM, and ApoA5.

Results

In comparison to the control group, the HDL, ApoM, and ApoA5 serum levels were lower (P < 0.05). HDL was positively correlated to ApoM and ApoA5 (P < 0.001), and ApoM was positively correlated to ApoA5 (r = 0.536, P < 0.001). HDL, ApoM, and ApoA5 were significantly increased in the patients of moderate and severe OSAHS after auto-continuous positive airway pressure treatment for 3 months (P < 0.05).

Conclusions

The HDL level was significantly lower in OSAHS patients. The decrease in serum ApoM and ApoA5 in OSAHS patients was correlated to the severity of OSAHS and HDL levels. Auto-continuous positive airway pressure treatment increased serum levels of ApoM, ApoA5, and HDL in OSAHS patients.