Respiratory disturbance index: an independent predictor of mortality in coronary artery disease

NoSAS score predicts cardiovascular disease in patients with obstructive sleep apnea

PURPOSE

The Lausanne NoSAS (Neck circumference, Obesity, Snoring, Age, Sex) score is a new tool for the identification of high-risk patients for obstructive sleep apnea (OSA). Up to now, no study has attempted to determine the role of NoSAS score in cardiovascular morbidity of patients with OSA. We aimed to investigate the relationships between NoSAS scores and CVD and also between severity of OSA, polysomnographic parameters, and NoSAS scores in patients with OSA.

METHODS

Patients with diagnosis of OSA by full-night polysomnography were recruited in the study. Based on apnea-hypopnea index (AHI) scores, the patients were categorized as OSA-negative (AHI < 5), mild OSA (5 ≤ AHI < 15), moderate OSA (15 ≤ AHI < 30), and severe OSA (AHI ≥ 30). The definition of cardiovascular diseases (CVD) included the presence of any of the diseases such as hypertension, coronary artery disease, heart failure, or arrhythmia.

RESULTS

A total of 1514 patients including cases with 199 OSA-negative, 391 mild, 342 moderate, and 582 severe OSA were enrolled in the study. NoSAS scores were significantly different between mild, moderate, and severe OSA groups. NoSAS scores were negatively correlated with minimum oxygen saturation values and positively with AHI and ODI (oxygen desaturation index) values (P < 0.001). NoSAS scores were significantly higher in patients with CVD, diabetes mellitus, and cerebrovascular disease compared with those without (P < 0.005). NoSAS cut-off values for hypertension (14), congestive heart failure (8.5), coronary artery disease (9), cerebrovascular event (11), and diabetes mellitus (10) were also determined.

CONCLUSION

NoSAS scores are associated with CVD and the severity of OSA. NoSAS scores may be useful to predict CVD in patients with OSA.

Overnight changes in uric acid, xanthine oxidoreductase and oxidative stress levels and their relationships with sleep-disordered breathing in patients with coronary artery disease

Serum uric acid (UA) level is associated with the high cumulative incidence or prevalence of coronary artery disease (CAD), and hyperuricemia is considered as an independent risk marker for CAD. Sleep-disordered breathing (SDB) is also associated with an increased risk of CAD. Several studies have shown that SDB is associated with hyperuricemia, but the mechanisms are unclear. We measured serum levels of UA and xanthine oxidoreductase (XOR) activity and urinary levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), all of which were assessed at 6 p.m. and the following 6 a.m. in males with CAD. In addition, nocturnal pulse oximetry was performed for the night. Overall 32 eligible patients with CAD were enrolled. Serum UA levels significantly increased overnight. (5.32 ± 0.98 mg/dl to 5.46 ± 1.02 mg/dl, p < 0.001) Moreover, XOR activity and urinary 8-OHdG levels significantly increased from 6 p.m. to 6 a.m. Furthermore, 3% Oxygen desaturation index (ODI) was correlated with the overnight changes in XOR activity (r = 0.36, P = 0.047) and urinary 8-OHdG levels (r = 0.41, P = 0.02). In addition, 3%ODI was independently correlated with the changes in XOR activity (correlation coefficient, 0.36; P = 0.047) and 8-OHdG (partial correlation coefficient, 0.63; P = 0.004) in multivariable analyses. SDB severity was associated with the overnight changes in XOR activity and urinary 8-OHdG, suggesting that SDB may be associated with oxidative stress via UA production. This trial is registered at University Hospital Medical Information Network (UMIN), number: UMIN000021624.

Outcomes in Patients with Acute Myocardial Infarction and Known Sleep Apnea: A Nationwide Analysis

Background. Sleep apnea (SA) is a common breathing disorder characterized by repetitive upper airway narrowing and closure. Although SA has been demonstrated to be an independent risk factor for all-cause mortality, the direct contribution of SA to worse cardiovascular prognosis may be difficult to evaluate, and its independent association with the different types of cardiovascular outcomes may be debated, particularly in the context of patients with acute myocardial infarction (AMI). The aim of this study was to assess the impact of known SA on the outcomes of hospitalized patients who have had an AMI by analyzing 10-year data collected from a national registry. Methods. This longitudinal cohort study was based on the national hospitalization database that covers hospital care for the entire French population, including all patients admitted with AMI from January 2010 to June 2019. The clinical outcomes for the analysis were as follows: all-cause death, cardiovascular death, ischemic stroke, new-onset atrial fibrillation (FA), and re-hospitalization for heart failure (HF). Results. Among the 797,212 patients who presented with an AMI (528,351 men and 268,861 women), 37,075 (4.7%) had documented SA. During follow-up (mean [SD] 1.8 [2.4] years, median [interquartile range] 0.7 [0.1-3.1] years), 163,845 deaths (of which 85,649 were cardiovascular deaths), 20,168 ischemic strokes, 58,498 new-onset AF, and 92,381 rehospitalizations due to HF were recorded. Patients with known SA had a worse prognosis in the short and medium term, but after adjusting for all covariables, SA was only independently associated with a higher risk of rehospitalization for HF and new-onset AF in men and women. Conclusion. Data from our large nationwide analysis confirm that known SA is associated with poor cardiovascular outcomes in patients who have had an AMI. However, this impact is tem-pered when the model is adjusted for age, cardiovascular risk, or other covariables. Further studies need to be conducted to assess the independent impact of SA on the prognosis of patients with AMI.

Cardiovascular Outcomes in Adults with Coronary Artery Disease and Obstructive Sleep Apnea with versus without Excessive Daytime Sleepiness in the RICCADSA Cinical Trial

Rationale: Recent randomized controlled trials did not show cardiovascular benefits of continuous positive airway pressure (CPAP) in adults with coronary artery disease (CAD) and obstructive sleep apnea (OSA) in intention-to-treat analyses. It has been argued that exclusion of patients with OSA with excessive daytime sleepiness (EDS), who may be most likely to benefit from CPAP treatment, may be a reason for the null results. Objectives: We addressed 1) the effect of concomitant EDS on adverse outcomes in patients with CAD and OSA; and 2) whether the cardiovascular benefit of CPAP adherence differs between individuals with versus without EDS. Methods: This was a secondary analysis of the RICCADSA (Randomized Intervention with CPAP in CAD and Obstructive Sleep Apnea) trial, conducted in Sweden between 2005 and 2013. Data were analyzed from 155 patients with CAD with OSA (apnea-hypopnea index ⩾ 15/h) and EDS (Epworth Sleepiness Scale score ⩾ 10), who were allocated to CPAP and 244 patients without EDS (ESS < 10), who were randomized to CPAP or no CPAP. Patients who were allocated to no CPAP or were nonadherent (CPAP usage < 4 h/night) were compared with adherent patients (CPAP usage ⩾ 4 h/night) at 1-year follow-up. Inverse probability of treatment weighting was applied to mimic randomization of EDS. The primary endpoint was the first event of repeat revascularization, myocardial infarction, stroke, or cardiovascular mortality. Results: The median follow-up was 52.2 months. The incidence of the primary endpoint did not differ significantly between the EDS versus no-EDS groups in the entire cohort. Within the adherent group, patients without EDS had a significantly decreased risk compared with patients with EDS (adjusted hazard ratio, 0.41; 95% confidence interval, 0.20-0.85; P = 0.02). Conclusions: Adverse cardiovascular outcomes did not differ by degrees of EDS for patients with CAD with OSA who were untreated or nonadherent to treatment. CPAP use, at least 4 h/night, was associated with reduced adverse outcomes in participants without EDS. Clinical trial registered with www.clinicaltrials.gov (NCT00519597).

The Burden of Comorbidities in Obstructive Sleep Apnea and the Pathophysiologic Mechanisms and Effects of CPAP

Micro-arousals and the repeated desaturation of oxyhemoglobin, which are typical in obstructive sleep apnea syndrome (OSAS), have adverse effects on the health of patients, leading to a wide range of complications such as cardiovascular (arterial hypertension, pulmonary hypertension, chronic heart failure, arrhythmias, myocardial infarction), cerebrovascular (strokes), metabolic (insulin resistance, obesity, diabetes mellitus, metabolic syndrome), gastrointestinal (non-alcoholic liver disease), urinary (chronic renal failure), and neuropsychiatric complications as well as a wide range of malignancies. These, in turn, have multilateral effects on familial, occupational, and social life, as well as increasing the risks of road traffic accidents and accidents at the workplace. Awareness, timely screening, and the prevention of complications play important roles in diagnosing and treating comorbid conditions. This review focuses on comorbidities in OSAS and the effect of Continuous Positive Airway Pressure (CPAP) therapy on their prognoses.

Current Smoking Determines the Levels of Circulating MPO and MMP-9 in Adults with Coronary Artery Disease and Obstructive Sleep Apnea

(1) Background: Obstructive sleep apnea (OSA) is common in patients with coronary artery disease (CAD), in which a rupture of atherosclerotic plaques and oxidative stress play a role in the initiation and progression of the disorder. Circulating levels of myeloperoxidase (MPO), as an oxidative stress marker, as well as matrix metalloproteinase-9 (MMP-9), as a destabilizer of plaques, are known to be elevated in patients with CAD and are associated with worse prognosis. Some studies have suggested that OSA is associated with MPO and MMP-9, but the effect of OSA on these biomarkers in cardiac cohorts is unknown. (2) Aims: We addressed the determinants of high MPO and MMP-9 in a CAD cohort with concomitant OSA. (3) Materials and Methods: The current study was a secondary analysis of the RICCADSA trial that was conducted in Sweden between 2005 and 2013. A total of 502 revascularized CAD patients with OSA (apnea-hypopnea index [AHI] ≥ 15 events/h; n = 391) or no-OSA (AHI < 5 events/h; n = 101), based on a home sleep apnea test, and who had blood samples at baseline were included in the analysis. The patients were dichotomized into a high or low MPO and MMP-9 groups, based on the median cut-off values. (4) Results: The mean age of the participants was 63.9 (±8.6), and 84% of the study cohort were men. Median values of MPO and MMP-9 levels were 116 ng/mL and 269 ng/mL, respectively. In different multivariate linear and logistic regression models, neither OSA nor OSA severity in terms of AHI and oxygenation indices were associated with the high MPO and MMP-9 levels. Current smoking was significantly associated with both high MPO (odds ratio [OR] 1.73, 95% confidence interval [CI] 1.06-2.84; p = 0.030) and high MMP-9 levels (OR 2.41, 95% CI 1.44-4.03; p < 0.001), respectively. Other significant determinants were revealed as beta blocker use (OR 1.81, 95% CI 1.04-3.16; p = 0.036) for high MPO as well as male sex (OR 2.07, 95% CI 1.23-3.50; p = 0.006) and calcium antagonist use (OR 1.91, 95% CI 1.18-3.09; p = 0.008) for high MMP-9 levels. (5) Conclusions: Current smoking, but not OSA, was significantly associated with high MPO and MMP-9 levels in this revascularized CAD cohort. Smoking status should be seriously taken into consideration while evaluating the effects of OSA and its treatment on long-term adverse cardiovascular outcomes in adults with CAD.

High-density lipoprotein cholesterol efflux capacity in patients with obstructive sleep apnea and its relation with disease severity

Background

Obstructive sleep apnea (OSA) is linked to an accelerated risk of cardiovascular disease (CVD). Some key CVD risk factors are present in patients suffering from OSA such as hypertension, inflammation, oxidative stress, and dyslipidemia. High-density lipoprotein (HDL) cholesterol efflux capacity (CEC) is proposed as a reliable biomarker of HDL function and the present study aimed to quantify this biomarker in patients with OSA.

Methods

ATP binding cassette subfamily A member 1 (ABCA1), non-ABCA1, and total CEC were determined in 69 polysomnographic-confirmed OSA patients and 23 controls. Moreover, paraoxonase (PON) activities, high-sensitivity C-reactive protein (hsCRP), apolipoprotein B (apo B), and apolipoprotein A-I (apo A-I) circulating levels were quantified in the studied population.

Results: All CEC measures were reduced in the OSA group compared to the control group. Strikingly, ABCA1 CEC was diminished in severe OSA in comparison with mild OSA. Furthermore, PON activities and apo A-I showed lower levels, while hsCRP and apo B were elevated in OSA patients compared to controls. Moreover, ABCA1 CEC showed an inverse association with hsCRP and a positive association with apo A-I, while non-ABCA1 CEC presented an association with HDL-C.

Conclusion

These results suggest the presence of an impaired HDL function in OSA. In particular, ABCA1 CEC was associated with disease severity and inflammation which could be a factor increasing the risk of CVD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-022-01723-w.

Influence of obstructive sleep apnoea on coronary artery disease in a Chinese population

OBJECTIVE

This study aimed to investigate the correlation between obstructive sleep apnoea (OSA) and the severity of coronary artery disease (CAD) assessed by angiography.

METHODS

This prospective study screened 273 patients diagnosed with CAD by coronary angiography. The severity of CAD was assessed by SYNTAX score. A total of 255 subjects were enrolled of whom 161 were diagnosed with OSA, with an apnoea-hypopnoea index ≥5/hour. Ninety-four CAD patients without OSA were used as controls. The relationship between OSA and CAD was analysed by multiple linear regression.

RESULTS

The prevalence of OSA in CAD patients was 63.1%. The prevalences of single-vessel, two-vessel, and three-vessel disease were similar in the two groups. However, CAD was significantly more severe in patients with OSA, measured by SYNTAX score, than in those without OSA. OSA was independently associated with CAD after adjusting for traditional risk factors.

CONCLUSIONS

OSA is relatively common among patients with CAD in China. The independent association between OSA and CAD, even after adjusting for traditional confounders, suggests that OSA should be taken into account when considering the risk factors for CAD. The present findings highlight the important adverse influence of OSA on the severity of CAD.

Pathways of Microcirculatory Endothelial Dysfunction in Obstructive Sleep Apnea: A Comprehensive Ex Vivo Evaluation in Human Tissue

BACKGROUND

The mechanism and markers of cardiovascular disease (CVD) in obstructive sleep apnea (OSA) remain unknown. The microcirculation is the site of early changes in OSA patients who are free of CVD risk.

METHODS

Patients with newly diagnosed moderate to severe OSA (n = 7) were studied before and 12 weeks after intensive treatment with continuous positive airway pressure (CPAP), along with weight and age matched controls (n = 7). Microcirculatory vessels were isolated from gluteal biopsies and changes in critical functional genes were measured.

RESULTS

The following genes changed after 12 weeks of intensive CPAP therapy in the microcirculatory vessels: angiotensin receptor type 1 (AGTR-1) (11.6 (3.4) to 6 (0.8); P = 0.019); NADPH oxidase (NOX4) (0.85 (0.02) to 0.79 (0.11); P = 0.016); and dimethylarginine dimethylaminohydrolase (DDAH 1) (1 (0.31) to 0.55 (0.1); P = 0.028). Despite decreased nitric oxide (NO) availability as measured indirectly through brachial artery flow-mediated dilation, endothelial NO synthase (NOS3) did not change with CPAP. Other disease markers of OSA that changed with treatment in the microcirculation were endothelin, hypoxia inducible factor 1a, nuclear factor kappa B, interleukin-8, and interleukin-6.

CONCLUSIONS

In this ex vivo evaluation of the microcirculation of patients with OSA and no CVD risk, several pathways of CVD were activated supporting that OSA independently induces microcirculatory endothelial dysfunction and serving as disease-specific markers for future pharmacological targeting of OSA-related CVD risk. The findings support the role of renin-angiotensin activation and endothelial oxidative stress in the decreased microcirculatory NO availability in OSA.

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.

Abnormal Sleep-Related Breathing Related to Heart Failure

Sleep-disordered breathing (SDB) is highly prevalent in patients with heart failure (HF). Untreated obstructive sleep apnea (OSA) and central sleep apnea (CSA) in patients with HF are associated with worse outcomes. Detailed sleep history along with polysomnography (PSG) should be conducted if SDB is suspected in patients with HF. First line of treatment is the optimization of medical therapy for HF and if symptoms persist despite optimization of the treatment, positive airway pressure (PAP) therapy will be started to treat SDB. At present, there is limited evidence to prescribe any drugs for treating CSA in patients with HF. There is limited evidence for the efficacy of continuous positive airway pressure (CPAP) or adaptive servo-ventilation (ASV) in improving mortality in patients with heart failure with reduced ejection fraction (HFrEF). There is a need to perform well-designed studies to identify different phenotypes of CSA/OSA in patients with HF and to determine which phenotype responds to which therapy. Results of ongoing trials, ADVENT-HF, and LOFT-HF are eagerly awaited to shed more light on the management of CSA in patients with HF. Until then the management of SDB in patients with HF is limited due to the lack of evidence and guidance for treating SDB in patients with HF.

Effect of obstructive sleep apnea on cerebrovascular compliance and cerebral small vessel disease

Reduced cerebrovascular compliance is the major mechanism of cerebral small vessel disease (SVD). Obstructive sleep apnea (OSA) also promotes SVD development, but the underlying mechanism was not elucidated. We investigated the association among OSA, cerebrovascular compliance, and SVD parameters. This study retrospectively included individuals ≥ 50 years of age, underwent overnight polysomnographic (PSG) for the evaluation of OSA, and performed MRI and transcranial Doppler (TCD) within 12 months of interval without a neurological event between the evaluations. TCD parameters for the cerebrovascular compliance included middle cerebral artery pulsatility index (MCA PI) and mean MCA resistance index ratio (MRIR). SVD parameters included white matter hyperintensity (WMH) volume, number of lacunes, enlarged perivascular space (ePVS) score, and the presence of microbleeds or lacunes. Ninety-seven individuals (60.8% male, mean age 70.0±10.5 years) were included. MRIR was associated with higher respiratory distress index (B = 0.003; 95% confidence interval [CI] 0.001-0.005; P = 0.021), while MCA PI was not associated with any of the PSG markers for OSA severity. Apnea-hypopnea index was associated with the log-transformed total WMH volume (B = 0.008; 95% confidence interval [CI] 0.001-0.016; P = 0.020), subcortical WMH volume (B = 0.015; 95% CI 0.007-0.022; P<0.001), total ePVS score (B = 0.024; 95% CI 0.003-0.045; P = 0.026), and centrum semiovale ePVS score (B = 0.026; 95% CI 0.004-0.048; P = 0.019), and oxygen-desaturation index with periventricular WMH volume, independently from age, MCA PI, and MRIR. This study concluded that OSA is associated with reduced cerebrovascular compliance and also with SVD independently from cerebrovascular compliance. Underlying pathomechanistic link might be region specific.

Obstructive Sleep Apnea: A Surgeon's Perspective

Obstructive sleep apnea (OSA) is a complex medical disorder with significant impact on mortality, quality of life, and long-term cardiovascular outcomes. The apnea-hypopnea index does not correlate well with either quality-of-life measures or health outcomes, so other outcome measures must be evaluated in treatment of OSA. OSA can be successfully treated through behavioral, nonsurgical, and surgical methods with improvements in quality of life, morbidity, and mortality. Surgical intervention should be considered in patients who are noncompliant with or fail positive airway pressure use. As is true with PAP therapy, surgery for OSA improves mortality and symptoms of OSA even when the polysomnogram does not fully normalize.

The effect of chronic intermittent hypoxia in cardiovascular gene expression is modulated by age in a mice model of sleep apnea

STUDY OBJECTIVES

Chronic intermittent hypoxia (CIH) is a major determinant in obstructive sleep apnea cardiovascular morbidity and this effect is influenced by age. The objective of the present study was to assess the differential molecular mechanisms at gene-level expression involved in the cardiovascular remodeling induced by CIH according to chronological age.

METHODS

Two- and 18-month-old mice (N = 8 each) were subjected to CIH or normoxia for 8 weeks. Total messenger RNA (mRNA) was extracted from left ventricle myocardium and aortic arch, and gene expression of 46 intermediaries of aging, oxidative stress, and inflammation was measured by quantitative real-time polymerase chain reaction.

RESULTS

Cardiac gene expression of Nrf2 (2.05-fold increase, p < 0.001), Sod2 (1.9-fold increase, p = 0.035), Igf1r (1.4-fold increase, p = 0.028), Mtor (1.8-fold increase, p = 0.06), Foxo3 (1.5-fold increase, p = 0.020), Sirt4, Sirt6, and Sirt7 (1.3-fold increase, p = 0.012; 1.1-fold change, p = 0.031; 1.3-fold change, p = 0.029) was increased after CIH in young mice, but not in old mice. In aortic tissue, endothelial isoform of nitric oxide synthase was reduced in young mice (p < 0.001), Nrf2 was reduced in 80% (p < 0.001) in young mice and 45% (p = 0.07) in old mice, as its downstream antioxidant target Sod2 (82% reduced, p < 0.001). IL33.

CONCLUSIONS

CIH effect in gene expression is organ-dependent, and is modulated by age. CIH increased transcriptional expression of genes involved in cardioprotection and cell survival in young, but not in old mice. In aortic tissue, CIH reduced gene expression related to an antioxidant response in both young and old mice, suggesting vascular oxidative stress and a proaging process.

Requirements for Supporting Diagnostic Equipment of Respiration Process in Humans

There is abundant worldwide research conducted on the subject of the methods of human respiration process examination. However, many of these studies describe methods and present the results while often lacking insight into the hardware and software aspects of the devices used during the research. This paper’s goal is to present new equipment for assessing the parameters of human respiration, which can be easily adopted for daily diagnosis. This work deals with the issue of developing the correct method of obtaining measurement data. The requirements of the acquisition parameters are clearly pointed out and examples of the medical applications of the described device are shown. Statistical analysis of acquired signals proving its usability is also presented. In the examples of selected diseases of the Upper Respiratory Tract (URT), the advantages of the developed apparatus for supporting the diagnosis of URT patency have been proven.

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.

Association of lower nighttime diastolic blood pressure and hypoxia with silent myocardial injury: The Japan Morning Surge-Home Blood Pressure study

Whether marked nocturnal blood pressure (BP) reduction is associated with cardiovascular disease (CVD) is still controversial. In addition, no report has yet discussed the relationship between lower nocturnal BP and CVD, involving modification by nighttime hypoxia. We evaluated 840 patients who had one or more cardiovascular risk factors by measuring their high‐sensitivity cardiac troponin T (Hs‐cTnT), N‐terminal pro‐B‐type natriuretic peptide (NT‐pro BNP), and nighttime saturation levels and performing ambulatory BP monitoring. The lowest tertile in nighttime diastolic BP (DBP) (≤66 mmHg) had increased likelihood of the presence of ≥0.014 ng/ml of Hs‐cTnT compared with the second tertile (odds ratio [OR] 1.91, 95% confidence interval [CI] 1.01–3.63), and the lowest tertile of minimum blood oxygen saturation (≤81%) had increased likelihood of the presence of ≥0.014 ng/ml of Hs‐cTnT compared with the third tertile (OR 2.15, 95% CI 1.13–4.10). Additionally, the patients with both lowest tertile of nighttime DBP and minimum SpO2 showed increased likelihood of the presence of ≥0.014 ng/ml of Hs‐cTnT compared with those without this combination (OR 2.93, 95% CI 1.40–6.16). On the other hand, these associations were not found in the presence of ≥125 pg/ml of NT‐pro BNP. In the clinical population, each of lower nocturnal DBP and nighttime hypoxia was associated with asymptomatic myocardial injury, which was represented as higher Hs‐cTnT, and coexisting lower nocturnal DBP and nighttime hypoxia had an additive effect on the risk of myocardial injury.

Metabolic syndrome - Evidence-based strategies for patient optimization

With the increasing prevalence of obesity worldwide, it is inevitable that anesthesiologists will encounter patients with metabolic syndrome. Metabolic syndrome encompasses multiple diseases, which include central obesity, hypertension, dyslipidemia, and hyperglycemia. Given the involvement of multiple diseases, metabolic syndrome involves numerous complex pathophysiological processes that negatively impact several organ systems. Some of the organ systems that have been well-documented to be adversely affected include the cardiovascular, pulmonary, and endocrine systems. Metabolic syndrome also leads to prolonged hospital stays, increased rates of infections, a greater need for care after discharge, and overall increased healthcare costs. Several interventions have been suggested to mitigate these negative outcomes ranging from lifestyle modifications to surgeries. Therefore, anesthesiologists should understand metabolic syndrome and formulate management strategies that may modify perianesthetic and surgical risks.

Long-term effects of cardiac rehabilitation on sleep apnea severity in patients with coronary artery disease

STUDY OBJECTIVES

Sleep apnea (SA) is prevalent among patients with coronary artery disease (CAD) and increases cardiovascular risk. A previous study showed that 1 month of cardiac rehabilitation (CR) reduced severity of SA in patients with CAD by reducing fluid accumulation in the legs during the day and the amount of fluid shifting rostrally into the neck overnight. The aim of this study was to evaluate whether CR will lead to longer-term attenuation of SA in patients with CAD.

METHODS

Fifteen patients with CAD and SA who had participated in a 1-month randomized trial of the effects of exercise training on SA were followed up until they completed 6 months of CR (age: 65 ± 10 years; body mass index: 27.0 ± 3.9 kg/m²; apnea-hypopnea index [AHI]: 39.0 ± 16.7). The AHI was evaluated at baseline by polysomnography and then at 6 months by portable monitoring at home. Cardiorespiratory fitness (VO_2peak) was evaluated via a graded cardiopulmonary exercise test at baseline and 6 months later. The 6-month CR program included once weekly, 90-minute, in-facility exercise sessions, and 4 days per week at-home exercise sessions.

RESULTS

After 6 months of CR, there was a 54% reduction in the AHI (30.5 ± 15.2 to 14.1 ± 7.5, P < .001). Body mass index remained unchanged, but VO_2peak increased by 27% (20.0 ± 6.1 to 26.0 ± 8.9 mL/kg/min, P = .04).

CONCLUSIONS

Participation in CR is associated with a significant long-term decrease in the severity of SA. This finding suggests that attenuation of SA by exercise could be a mechanism underlying reduced mortality following participation in CR in patients with CAD and SA.

CLINICAL TRIAL REGISTRATION

This study is registered at www.controlled-trials.com with identifier number ISRCTN50108373.

Culprit Plaque Characteristics in Patients With Sleep-Disordered Breathing Undergoing Percutaneous Coronary Intervention: An Intravascular Ultrasound Study

Background

Sleep‐disordered breathing (SDB) is a novel cardiovascular risk factor. However, the coronary plaque characteristics of patients with SDB with coronary artery disease are still unclear.

Methods and Results

This study included 289 consecutive patients with coronary artery disease undergoing percutaneous coronary intervention. Plaque characteristics of the culprit lesion were assessed by preintervention intravascular ultrasound. The presence of SDB was defined as a 3% oxygen desaturation index of ≥15 events per hour measured by nocturnal pulse oximetry. Of 289 patients, the median 3% oxygen desaturation index was 9.6 (interquartile range, 5.1–16.6), and 88 patients (30.4%) were defined as having SDB. Compared with the no‐SDB group, the SDB group had a larger total atheroma volume of the culprit lesion (224.5 mm³ versus 190.8 mm³, P=0.05). The median maximum attenuation and calcification angle were 140° and 130°, respectively. Attenuated plaque with a maximum attenuation angle >140° was more frequently observed in the SDB group compared with the no‐SDB group (34.9% versus 22.6%; P=0.03). However, there were no statistically significant differences between groups in the maximum calcium angle and the frequency of calcific plaques with a maximum calcium angle >130°. Multivariable logistic regression analysis showed that the presence of SDB was a significant predictor of a greater ultrasound attenuation angle (>140°) (odds ratio, 1.86; 95% confidence interval, 1.02–3.39; P=0.04).

Conclusions

SDB was associated with larger atheroma plaque volume and a greater ultrasound attenuation, which are discriminators of plaque vulnerability. Further studies are needed to clarify the effects of SDB treatment on coronary plaque lesions.

Obstructive sleep apnea, sleep symptoms, and their association with cardiovascular disease

OBJECTIVES

To determine the frequency of obstructive sleep apnea (OSA), insomnia, restless legs, and other sleep symptoms in patients with cardiovascular disease and the association of these sleep disorders with quantitative cardiovascular measures.

METHODS

Study design was a cross-sectional survey and retrospective chart review. A questionnaire containing validated sleep symptoms was distributed to 202 patients with cardiovascular disease at a tertiary referral cardiology clinic. Following a focused review of these patients' medical charts, their questionnaire responses were examined for associations with clinical cardiovascular parameters.

RESULTS

Twenty-one percent of patients reported a prior diagnosis of OSA. A total of 115 patients (60%) had at least one additional sleep symptom. Clinically significant insomnia was significantly associated with heart disease (relative risk [RR] = 1.5, confidence interval [CI] = 1.1 to 2.1), prior myocardial infarction or cerebrovascular accident (RR = 2.1, CI = 1.2 to 3.6), and heart failure (RR = 2.2, CI = 1.3 to 3.8). Left ventricular ejection fraction was significantly associated with insomnia by Insomnia Severity Index (β = -0.52, CI = -0.89 to -0.13).

CONCLUSION

The frequency of OSA in patients in this tertiary cardiology clinic was higher than the general population in the United States, with the majority of patients experiencing at least one sleep symptom. Insomnia symptoms were shown to be associated with multiple cardiovascular measures, including left ventricular ejection fraction. These findings imply an interwoven relationship between cardiovascular and sleep symptoms as captured by validated sleep questionnaires.

LEVEL OF EVIDENCE

IV Laryngoscope, 130:1595-1602, 2020.

Obstructive sleep apnoea and coronary artery disease

Obstructive sleep apnoea (OSA) is a highly prevalent disorder, which causes significant nocturnal and daytime symptoms, reduced quality of life, and impaired functional capacity. Importantly, however, OSA also appears to predispose to the development of a number of cardiovascular and metabolic diseases, including diabetes, hypertension, and stroke. In this review we explore its relationship with coronary artery disease (CAD), discussing mechanisms whereby it may promote the development of atherosclerosis, evidence of its effect on CAD incidence and outcomes, and coronary imaging studies in subjects with OSA. Finally, we shall evaluate the current evidence regarding the impact of continuous positive airway pressure therapy on CAD outcomes in OSA patients.

Influence of sleep-disordered breathing assessed by pulse oximetry on long-term clinical outcomes in patients who underwent percutaneous coronary intervention

BACKGROUND

Sleep-disordered breathing (SDB) has been recognized as an important risk factor for coronary artery disease (CAD). However, SDB was not fully examined, because sleep studies are limited. Nocturnal pulse oximetry has been suggested to be a useful tool for evaluating SDB. Therefore, the aim of this study was to investigate the influence of SDB assessed by nocturnal pulse oximetry on clinical outcomes in patients who underwent percutaneous coronary intervention (PCI).

METHODS

We conducted a prospective, multicenter, observational cohort study, wherein SDB was assessed by finger pulse oximetry in patients who underwent PCI from January 2014 to December 2016. SDB was defined as 4% oxygen desaturation index of 5 and higher. The primary endpoint was major adverse cardiac or cerebrovascular event (MACCE), defined as a composite of all-cause mortality, acute coronary syndrome, and/or stroke.

RESULTS

Of 539 patients, 296 (54.9%) had SDB. MACCE occurred in 32 patients (5.8%) during a median follow-up of 1.9 years. The cumulative incidence of MACCE was significantly higher in patients with SDB (P = 0.0134). In the stepwise multivariable Cox proportional model, the presence of SDB was a significant predictor of MACCE (hazard ratio 2.26; 95% confidence interval 1.05-5.4, P = 0.036).

CONCLUSIONS

SDB determined by nocturnal pulse oximetry was associated with worse clinical outcomes in patients who underwent PCI. Screening for SDB with nocturnal pulse oximetry was considered to be important for risk stratification in patients with CAD.

Sleep Apnea in Heart Failure

PURPOSE OF REVIEW

In this review, we discuss the current treatment options for sleep-disordered breathing (SDB) in patients with heart failure (HF). We address the role of positive airway pressure (PAP) devices and other emerging therapies. The review includes discussion of recent trials that reported negative consequences for the PAP devices in patients with heart failure.

RECENT FINDINGS

Optimal guideline-directed medical therapies of HF and PAP devices have been the mainstay treatments for HF patients with SDB. Recently, randomized controlled trials (RCTs) evaluated the effect of PAP on clinical outcomes in patients with cardiovascular (CV) disease and heart failure and found no benefit in decreasing fatal and non-fatal CV events. The Sleep Apnea Cardiovascular Endpoints (SAVE) trial evaluated continuous positive airway pressure (CPAP) ventilation in patients with CV disease and obstructive sleep apnea (OSA) and did not observe any improvement in CV effect. In patients with HF and central sleep apnea (CSA), adaptive servo-ventilation (ASV) was hypothesized to help HF outcomes, but the Adaptive Servo-Ventilation for Central Sleep Apnea in Systolic Heart Failure (SERVE-HF) trial did not show any mortality benefit. Instead, the trial suggested an increase in all-cause and CV mortality in the treatment arm. currently, studies have not shown the use of PAP therapy to improve any risks of CV outcomes or death in HF patients with sleep apnea, but some associations with improvements in symptoms from OSA have been observed.

Application of Personalized, Predictive, Preventative, and Participatory (P4) Medicine to Obstructive Sleep Apnea. A Roadmap for Improving Care?

Dr. Leroy Hood promotes a paradigm to advance medical care that he calls P4 medicine. The four Ps are: personalized, predictive, preventative, and participatory. P4 medicine encourages a convergence of systems medicine, the digital revolution, and consumer-driven healthcare. Might P4 medicine be applicable to obstructive sleep apnea (OSA)? OSA should be personalized in that there are different structural and physiological pathways to disease. Obesity is a major risk factor. The link between obesity and OSA is likely to be fat deposits in the tongue compromising the upper airway. Clinical features at presentation also vary between patients. There are three distinct subgroups: (1) patients with a primary complaint of insomnia, (2) relatively asymptomatic patients with a high prevalence of cardiovascular comorbidities, and (3) excessively sleepy patients. Currently, there have been limited efforts to identify subgroups of patients on the basis of measures obtained by polysomnography. Yet, these diagnostic studies likely contain considerable predictive information. Likewise, there has currently been limited application of -omic approaches. Determining the relative role of obesity and OSA for particular consequences is challenging, because they both affect the same molecular pathways. There is evidence that the effects of OSA are modified by the level of obesity. These insights may lead to improvements in predicting outcomes to personalized therapies. The final P-participatory-is ideally suited to OSA, with technology to obtain extensive data remotely from continuous positive airway pressure machines. Providing adherence data directly to patients increases their use of continuous positive airway pressure. Thus, the concept of P4 medicine is very applicable to obstructive sleep apnea and can be the basis for future research efforts.

Long-term use of continuous positive airway pressure therapy in coronary artery disease patients with nonsleepy obstructive sleep apnea

BACKGROUND

Excessive daytime sleepiness is a frequent symptom of obstructive sleep apnea (OSA) and has been proposed as a motivator for adherence to continuous positive airway pressure (CPAP) therapy. However, excessive daytime sleepiness is absent in many patients with coronary artery disease (CAD) and concomitant OSA. We evaluated long-term use of CPAP and predictors of CPAP use in nonsleepy and sleepy OSA patients from a CAD cohort.

HYPOTHESIS

Long-term CPAP use is lower in CAD patients with nonsleepy OSA vs sleepy OSA.

METHODS

Nonsleepy (Epworth Sleepiness Scale [ESS] score < 10) OSA patients randomized to CPAP (n = 122) and sleepy (ESS ≥10) OSA patients offered CPAP (n = 155) in the RICCADSA trial in Sweden were included in this substudy. The median follow-up was 4.8 years for the main trial, with a predefined minimum follow-up of 2 years.

RESULTS

The probability of remaining on CPAP at 2 years was 60% in nonsleepy patients and 77% in sleepy patients. Multivariate analyses indicated that age and hours of CPAP use per night at 1 month were independently associated with long-term CPAP use in nonsleepy patients. In the sleepy phenotype, body mass index, acute myocardial infarction at baseline, and hours of CPAP use per night at 1 month were predictors of long-term CPAP use.

CONCLUSIONS

Long-term use of CPAP is likely to be challenging for CAD patients with nonsleepy OSA. Early CPAP use is an important predictor of continued long-term use of CPAP, so optimizing patients' initial experience with CPAP could promote adherence.

Prevalence of Sleep-Disordered Breathing and Patient Characteristics in a Coronary Artery Disease Cohort Undergoing Cardiovascular Rehabilitation

PURPOSE

Coronary artery disease (CAD) is a leading cause of death and identification of risk factors for CAD is crucial. One such potential risk factor is sleep-disordered breathing (SDB). This prospective cohort study investigated the prevalence of SDB and determined risk factors for the presence of SDB in a large CAD cohort undergoing cardiac rehabilitation.

METHODS

A total of 1425 patients with confirmed CAD starting rehabilitation were screened for SDB using cardiorespiratory polygraphy (n = 921) or polygraphy plus pulse oximetry (n = 484).

RESULTS

A total of 1408 patients were included; 69.5% were male, 78% had acute coronary syndrome, and 22% had stable CAD. The prevalence of SDB (apnea-hypopnea index [AHI] ≥5/h) was 83%. Moderate to severe SDB (AHI ≥15/h) was present in 53%. Up to 70% of coronary artery bypass graft (CABG) recipients had an AHI ≥15/h versus 33% of those who had not undergone CABG. SDB severity did not vary significantly in patients with stable CAD or on the basis of left ventricular ejection fraction. SDB was more severe and the frequency of oxygen desaturation was higher in men than in women. Multivariate logistic regression identified age, sex, body mass index, and CABG as independent risk factors for severe SDB.

CONCLUSION

SDB is a highly prevalent comorbidity in patients with CAD, particularly those who have undergone CABG. These results strengthen existing associations and emphasize the importance of diagnosing and monitoring SDB in patients with CAD entering a cardiac rehabilitation program. Early diagnosis and intervention has the potential to have a beneficial effect on CAD prognosis.

Recognition and treatment of sleep-disordered breathing: an important component of chronic disease management

Sleep-disordered breathing (SDB) is a highly prevalent condition, and is associated with many debilitating chronic diseases. The role of untreated obstructive sleep apnea (OSA) in arterial hypertension has been recognized in international guidelines. Treatment with continuous positive airway pressure (CPAP) is associated with clinically-relevant reductions in blood pressure. In heart failure (HF), SDB is associated with worse prognosis and increased mortality. Major HF guidelines recommend that patients should be treated for sleep apnea to improve their HF status. Severe OSA increases the risk of arrhythmias, including atrial fibrillation, influences risk management in stroke, and is highly prevalent in patients with type 2 diabetes. Effective treatment with CPAP improves the success of antiarrhythmic interventions, improves outcomes in stroke and reduces hyperglycemia in diabetes. Patients with coronary artery disease also have a high prevalence of SDB, which is independently associated with worse outcomes. The role of CPAP for secondary cardiovascular prevention remains to be determined. Data from large, well-conducted clinical trials have shown that noninvasive ventilation, targeted to markedly reduce hypercapnia, significantly improves survival and reduces readmission in stable hypercapnic chronic obstructive pulmonary disease. The association of SDB with chronic diseases contributes to the high healthcare costs incurred by SDB patients. SDB also has an important negative impact on quality of life, which is reversed by CPAP treatment. The high prevalence of SDB, and its association with diseases that cause significant morbidity and mortality, suggest that the diagnosis and management of SDB is an important therapeutic goal. First, adherent CPAP treatment significantly improves the quality of life of all patients with SDB; second, it eliminates the negative impact of untreated SDB on any associated chronic diseases; and third, it significantly reduces the increased costs of all hospital and medical services directly associated with untreated SDB. In short, the recognition and treatment of SDB is vital for the continued health and wellbeing of individual patients with SDB.

A Practical Approach to the Identification and Management of Sleep-Disordered Breathing in Heart Failure Patients

Sleep-disordered breathing (SDB) is a major health problem affecting much of the general population. Although SDB is responsible for rapid progression of heart failure (HF) and the worsening morbidity and mortality, advanced HF state is associated with accelerated development of SDB. In the face of recent developments in SDB treatment and availability of effective therapeutic options known to improve quality of life, exercise tolerance, and heart function, most HF patients with SDB are left unrecognized and untreated. This article provides an overview of SDB in HF with focus on practical approaches intended to facilitate screening and treatment.

The association of kidney function with repetitive breath-hold diving activities of female divers from Korea, Haenyeo

Background

Voluntary apnea during breath-hold diving (BHD) induces cardiovascular changes including bradycardia, reduced cardiac output, and arterial hypertension. Although the impacts of repetitive BHD on cardiovascular health have been studied previously, the long-term risk for kidney dysfunction has never been investigated.

Methods

A cross-sectional propensity score-matched study was performed to evaluate the influence of repetitive long-lasting BHD on kidney function. Using matching propensity scores (PS), 715 breath-hold female divers (Haenyeo) and non-divers were selected for analysis from 1,938 female divers and 3,415 non-divers, respectively. The prevalence of chronic kidney disease (CKD) defined as an estimated glomerular filtration rate (eGFR) calculated to be less than 60 ml/min/1.73 m² was investigated in both diver and non-diver groups.

Results

The prevalence of CKD was significantly higher in breath-hold divers compared with non-divers after PS matching (12.6% vs. 8.0%, P = 0.004). In multivariate analysis, BHD activity was significantly associated with the risk of CKD in an unmatched cohort (OR, 1.976; 95% CI, 1.465–2.664). In the PS-matched cohort, BHD remained the independent risk factor for CKD even after adjusting for multiple covariates (OR 1.967; 95% CI, 1.341–2.886).

Conclusion

Shallow but repetitive intermittent apnea by BHD, sustained for a long period of time, may potentially cause a deterioration in kidney function, as a long-term consequence.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-017-0481-1) contains supplementary material, which is available to authorized users.

Diagnostic accuracy of carotid intima media thickness in predicting coronary plaque burden on coronary computed tomography angiography in patients with obstructive sleep apnoea

AIM

To assess the diagnostic accuracy of common carotid artery intima media thickness (CIMT) for coronary artery disease (CAD) detection in patients with obstructive sleep apnoea (OSA).

MATERIALS & METHODS

Patients with clinically suspected OSA prospectively underwent polysomnography (PSG), ultrasound CIMT measurement and coronary computed tomography angiography (CTA). An average CIMT of ≥0.9 mm in either common carotid artery designated as a positive test. Coronary CTA was the reference standard for the presence of CAD. Coronary plaque presence, volume, density and type were correlated with CIMT findings.

RESULTS

35 consecutive male patients were enrolled from sleep clinic. Two patients had no evidence of OSA on PSG (apnoea-hypopnea index [AHI]<5/hr), and were excluded. Of the remaining 33, 18 (54%) had mild-moderate OSA (AHI 5-30/hr) and 15 (46%) had severe OSA (AHI >30/hr). Eight (24%) patients had CAD on coronary CTA. Coronary plaques were predominantly non- or partly calcified, and located in proximal coronary artery segments. Sensitivity, specificity, positive and negative predictive and likelihood ratios for a positive CIMT (≥0.9 mm) in diagnosing CAD were 0.5 (95% confidence interval: 0.76-0.12), 0.96 (1-0.89), 80, 85.7, 12.5 and 0.52 respectively. The adjusted odds ratio was 40.8.

CONCLUSION

In patients with OSA, CIMT is a highly specific but poorly sensitive test for detecting CAD.

Evaluation of Fibrinolytic Inhibitors: Alpha-2-Antiplasmin and Plasminogen Activator Inhibitor 1 in Patients with Obstructive Sleep Apnoea

Obstructive sleep apnoea (OSA) induces thrombophilia and reduces fibrinolysis. Alpha-2-antiplasmin (a-2-AP) and plasminogen activator inhibitor 1 (PAI-1) are major inhibitors of the fibrinolytic system. Increased concentrations of these factors are associated with a higher risk of cardiovascular diseases. The aim of this study was to assess plasma a-2-AP and PAI-1 in patients with OSA and evaluate correlations with the polysomnographic record and selected risk factors of cardiovascular diseases. The study group comprised 45 patients with OSA, and the control group consisted of 19 patients who did not meet the diagnostic criteria of OSA. Plasma a-2-AP and PAI-1 concentrations were assessed by enzyme-linked immunosorbent assay (ELISA). In the study group, the median value of plasma a-2-AP was higher than that of the control group (157.34 vs. 11.89 pg/ml, respectively, P<0.0001). A-2-AP concentration increased proportionally to the severity of OSA. The concentration of a-2-AP was positively correlated with the apnoea-hypopnoea index (AHI), apnoea index (AI), respiratory disturbances time (RDT), and desaturaion index (DI), and negatively correlated with mean and minimal oxygen saturation (SpO2 mean, SpO2 min, respectively). The median value of PAI-1 was higher in the study group than the control group (12.55 vs. 5.40 ng/ml, respectively, P = 0.006) and increased along with OSA severity. PAI-1 concentration was positively correlated with AHI, AI, RDT, DI, and body mass index (BMI) and negatively correlated with SpO2 mean and SpO2 min. Higher plasma concentrations of a-2-AP and PAI-1 in patients with OSA indicated that these patients had increased prothrombotic activity. OSA increases the risk of cardiovascular complications as it enhances prothrombotic activity.

Monocyte Count/HDL Cholesterol Ratio and Cardiovascular Disease in Patients With Obstructive Sleep Apnea Syndrome: A Multicenter Study

BACKGROUND

Obstructive sleep apnea syndrome (OSAS) is an independent risk factor for cardiovascular disease (CVD). Although monocyte to high-density lipoprotein cholesterol ratio (MHR) is increasingly being implicated in cardiovascular morbidity and mortality, no study has attempted to determine the role of MHR in cardiovascular morbidity of patients with OSAS. We aimed to investigate the association between MHR and CVD in patients with OSAS and the relationship between severity of OSAS, polysomnographic parameters, and MHR.

METHODS

In this cohort study, patients who had undergone a full-night polysomnography for the diagnosis of OSAS were recruited. Included patients were grouped according to the apnea-hypopnea index (AHI) as mild (5-15), moderate (15-30), and severe (>30) OSAS. Patients with AHI < 5 served as the control group. The presence of heart failure, coronary artery disease, or arrhythmia was defined as CVD.

RESULTS

A total of 1050 patients were included (131 controls, 222 mild, 228 moderate, and 469 severe OSAS). The severe group had higher MHR compared with the control and other OSAS groups (9.99, 12.11, 13.65, and 20.67 in control, mild, moderate, and severe OSAS groups, respectively, P < .001). The MHRs were significantly correlated with AHI, oxygen desaturation index, and minimum O₂ saturation values ( P < .001). Values of MHR were significantly higher in patients with CVD compared with those without ( P < .001). Multiple regression analysis demonstrated that MHR is an independent predictor of CVD.

CONCLUSION

The MHR is strongly associated with CVD and the severity of OSAS and might be used as a biomarker to predict CVD in patients with OSAS.

Impact of Sleep-Disordered Breathing on Long-Term Outcomes in Patients With Acute Coronary Syndrome Who Have Undergone Primary Percutaneous Coronary Intervention

BACKGROUND

Sleep-disordered breathing (SDB) has been recognized as an important risk factor for cardiovascular diseases; however, the impact of SDB on long-term outcomes in patients with acute coronary syndrome has not been fully evaluated.

METHODS AND RESULTS

We performed overnight cardiorespiratory monitoring of 241 patients with acute coronary syndrome who were successfully treated with primary percutaneous coronary intervention between January 2005 and December 2008. The presence of SDB was defined as apnea-hypopnea index ≥5 events per hour. The end point was incidence of major adverse cardiocerebrovascular events, defined as a composite of all-cause death, recurrence of acute coronary syndrome, nonfatal stroke, and hospital admission for congestive heart failure. Patients were followed for a median period of 5.6 years. Among the 241 patients who were finally enrolled, comorbidity of SDB with acute coronary syndrome was found in 126 patients (52.3%). The cumulative incidence of major adverse cardiocerebrovascular events was significantly higher in patients with SDB than in those without SDB (21.4% versus 7.8%, P=0.006). Multivariable analysis revealed that the presence of SDB was a significant predictor of major adverse cardiocerebrovascular events (hazard ratio 2.28, 95% CI 1.06-4.92; P=0.035).

CONCLUSIONS

The study's results showed that the presence of SDB among patients with acute coronary syndrome following primary percutaneous coronary intervention is associated with a higher incidence of major adverse cardiocerebrovascular events during long-term follow-up.

The Link Between Obstructive Sleep Apnea and Cardiovascular Disease

Obstructive sleep apnea (OSA) is common in the general population and highly prevalent in patients with cardiovascular disease. In this paper, we review (1) the pathophysiological mechanisms of OSA that may causally contribute to cardiovascular disease; (2) current evidence regarding the association between OSA and hypertension, stroke, ischemic heart disease, heart failure, atrial fibrillation, and cardiovascular mortality; and (3) the impact of continuous positive airway pressure (CPAP) treatment on cardiovascular risk factors and outcomes. We emphasize the importance of obesity as a comorbidity of OSA and a confounder in the association between OSA and cardiovascular disease. We also discuss the importance of addressing obesity in patients with OSA, as a strategy to reduce the burden of cardiovascular risk factors in this population. Implications for the approach of patients' OSA in clinical practice and future research directions are discussed.

Blood biomarkers of endocrine, immune, inflammatory, and metabolic systems in obstructive sleep apnea

OBJECTIVE/BACKGROUND

Obstructive sleep apnea (OSA) is a common disorder, affecting over 100 million adults. Untreated OSA leads to serious health consequences and perturbations in endocrine, immune, inflammatory, and metabolic systems. Study objectives are to evaluate the association between OSA and biomarkers, and to test the hypothesis that a combination of markers may be useful in screening for OSA.

PATIENTS/METHODS

A multicenter trial was conducted enrolling symptomatic male patients with suspected OSA. All subjects underwent in-laboratory overnight polysomnography. A non-symptomatic control group was also obtained. Eleven biomarkers were tested: HbA1c, CRP, EPO, IL-6, uric acid, cortisol, hGH, prolactin, testosterone, DHEA (Beckman Coulter UniCel DxC 600i Synchron® Access® Clinical Systems), IGF-1.

RESULTS

73 male subjects were enrolled; 26 had moderate/severe OSA. ROC curve analysis showed HbA1c, CRP, EPO, IL-6, and Uric Acid (AUCs: 0.76, 0.73, 0.65, 0.65, 0.61) were superior to the Epworth Sleepiness Scale (AUC: 0.52). Concurrent elevation of HbA1c and CRP provide even greater predictive power. A combination of elevated HbA1c, CRP, and EPO provided 0.08 increase in AUC (0.84 [0.75 - 0.94]) over individual markers (p<0.05), with high sensitivity (85%), and specificity (79%) for moderate/severe OSA.

CONCLUSIONS

OSA induces characteristic endocrine, immune, inflammatory, and metabolic disturbances that can be detected with blood biomarkers. These biomarkers are superior to standard screening questionnaires. Various clusters of these biomarkers have an even greater association with OSA and thus may represent physiologic signatures of the disorder that may have value in initial screening for OSA as well as for follow-up of therapy response.

A novel implantable device for the treatment of obstructive sleep apnea: clinical safety and feasibility

OBJECTIVE

Many cases of obstructive sleep apnea (OSA) involve collapse of the tongue base and soft palate during sleep, causing occlusion of the upper airway and leading to oxygen desaturation. Existing therapies can be effective, but they are plagued by patient adherence issues and the invasiveness of surgical approaches. A new, minimally invasive implant for OSA has been developed, which is elastic and contracts a few weeks after deployment, stabilizing the surrounding soft tissue. The device has had good outcomes in preclinical testing; this report describes the preliminary feasibility and safety of its implementation in humans.

PATIENTS AND METHODS

A prospective, multicenter, single-arm feasibility study was conducted. Subjects were adults with moderate-to-severe OSA who had previously failed or refused conventional continuous positive airway pressure treatment. Intraoperative feasibility data, postoperative pain, and safety information were collected for a 30-day postoperative period.

RESULTS

Forty subjects participated (37 men, three women; average age of 46.1 years); each received two tongue-base implants and two soft-palate implants. Surgical procedure time averaged 43 minutes. Postsurgical pain resolved readily in most cases; at 30 days post implantation, <20% of subjects reported pain, which averaged less than two out of ten. Adverse events were generally the mild and expected sequelae of a surgical procedure with general anesthesia and intraoral manipulation. The device was well tolerated. Implant extrusions were reported with soft-palate implants (n=12), while tongue-base implants required few revisions (n=2). Quantitative and qualitative sleep effectiveness outcomes (including full-night polysomnographic and quality-of-life measures) will be presented in a subsequent report.

CONCLUSION

Implantation of the device was feasible. Although a relatively high rate of extrusions occurred in the now-discontinued palate implants, tongue-base implants were largely stable and well tolerated. The minimally invasive and maintenance-free implant may provide a new alternative to higher morbidity surgical procedures.

Effects of exercise training on sleep apnoea in patients with coronary artery disease: a randomised trial

Overnight fluid shift from the legs to the neck and lungs may contribute to the pathogenesis of obstructive sleep apnoea (OSA) and central sleep apnoea (CSA). We hypothesised that exercise training will decrease the severity of OSA and CSA in patients with coronary artery disease (CAD) by decreasing daytime leg fluid accumulation and overnight rostral fluid shift.Patients with CAD and OSA or CSA (apnoea-hypopnoea index >15 events per h) were randomised to 4 weeks of aerobic exercise training or to a control group. Polysomnography, with measurement of leg, thoracic and neck fluid volumes and upper-airway cross-sectional area (UA-XSA) before and after sleep, was performed at baseline and follow-up.17 patients per group completed the study. Apnoea-hypopnoea index decreased significantly more in the exercise group than in the control group (31.1±12.9 to 20.5±9.4 versus 28.1±13.5 to 27.0±15.1 events per h, p=0.047), in association with a greater reduction in the overnight change in leg fluid volume (579±222 to 466±163 versus 453±164 to 434±141 mL, p=0.04) and by a significantly greater increase in the overnight change in UA-XSA in the exercise group (p=0.04).In patients with CAD and sleep apnoea, exercise training decreases sleep apnoea severity via attenuation of overnight fluid shift and an increase in UA-XSA.

Platelet-lymphocyte ratio is an independent predictor for cardiovascular disease in obstructive sleep apnea syndrome

There is a strong relationship between obstructive sleep apnea syndrome (OSAS) and cardiovascular disease (CVD). Chronic intermittent hypoxia, inflammation, oxidative stress, and endothelial dysfunction may constitute etiologic mechanisms, linking OSAS to CVD. Inflammation play an important role in the development of CVD. Platelet-lymphocyte ratio (PLR) is a new biomarker showing inflammation. No previous study has ever investigated the association between PLR, CVD and OSAS severity in patients with OSAS. This study was designed to investigate the association between PLR and CVD in patients with OSAS, and relationship between severity of OSAS, polysomnographic parameters and PLR. This was a cohort study in which patients who had undergone a full night polysomnoraphy for diagnosis of OSA were recruited. Patients were divided according to their apnea-hypopnea index (AHI) scores into OSAS negative (Group 1: AHI < 5), mild (Group 2: AHI, 5-15), moderate (Group 3:AHI,15-30), and severe OSAS (Group 4: AHI > 30) groups. The presence of heart failure, coronary artery disease or arrhythmia was defined as CVD. A total of 424 patients were included in this study. There were 57, 93, 82, and 192 patients in Groups 1, 2, 3, and 4, respectively. PLR were significantly different between groups (Group 1: 87.38; Group 2: 95.07; Group 3: 97.01, Group 4: 126.9, P < 0.05). PLR were significantly correlated with AHI, oxygen desaturation index, average and minimum O2 saturation values (P < 0.05). Values of PLR were significantly higher in patients with CVD compared with those without. Multiple regression analysis demonstrated that PLR is an independent predictor of CVD. PLR cut-off value for demonstrating the presence of CVD is higher than 108.56. In the light oh findings, PLR is strongly associated with the severity of OSAS and cardiovascular disease in OSAS patients. PLR might be used as a biomarker to predict CVD in OSAS patients.

A clinical approach to obstructive sleep apnea as a risk factor for cardiovascular disease

Obstructive sleep apnea (OSA) is associated with cardiovascular risk factors, cardiovascular diseases, and increased mortality. Epidemiological studies have established these associations, and there are now numerous experimental and clinical studies which have provided information on the possible underlying mechanisms. Mechanistic proof-of-concept studies with surrogate endpoints have been performed to demonstrate that treatment of OSA by continuous positive airway pressure (CPAP) has the potential to reverse or at least to attenuate not only OSA but also the adverse cardiovascular effects associated with OSA. However, no randomized studies have been performed to demonstrate that treatment of OSA by CPAP improves clinical outcomes in patients with cardiovascular risk factors and/or established cardiovascular disease and concomitant OSA. In the present review, we summarize the current knowledge on the role of OSA as a potential cardiovascular risk factor, the impact of OSA on cardiac function, the role of OSA as a modifier of the course of cardiovascular diseases such as coronary artery disease, atrial fibrillation, and heart failure, and the insights from studies evaluating the impact of CPAP therapy on the cardiovascular features associated with OSA.

Sleep Disturbances in the Elderly

Sleep disturbances are a common presenting symptom of older-age adults to their physicians. This article explores normal changes in sleep pattern with aging and primary sleep disorders in the elderly. Behavioral factors and primary psychiatric disorders affecting sleep in this population are reviewed. Further discussion examines sleep changes associated with 2 common forms of neurocognitive disorder: Alzheimer disease and Lewy Body Dementia. Common medical illnesses in the elderly are discussed in relation to sleep symptoms. Nonpharmacological and pharmacologic treatment strategies are summarized, with emphasis placed on risk of side effects in older adults. Future targets are considered.

Relationship between obstructive sleep apnea and 30-day mortality among patients with pulmonary embolism

Background:

Pulmonary embolism (PE) is the most life-threatening form of venous thrombosis which causes the majority of mortalities in this category. Obstructive sleep apnea (OSA) has been indicated as one of the risk factors for thromboembolism because of hemostatic alterations. The present study was designed to seek for the relationship between OSA and 30-day mortality of patients with PE.

Materials and Methods:

This prospective cohort study was conducted among 137 consecutive patients referred to hospital with symptoms of PE and preliminary stable hemodynamic. Confirmation of PE was made by multislice computed tomography pulmonary angiography and in the case of contraindication; V/Q lung scan and Doppler sonography were done. A STOP-Bang Questionnaire was used to determine patients with high- and low-risk of OSA. Patients were followed up for 1-month, and their survivals were recorded.

Results:

This study showed that there was no relationship between OSA and 30-day mortality (P = 0.389). Chronic kidney disease (P = 0.004), hypertension (P = 0.003), main thrombus (P = 0.004), and segmental thrombus (P = 0.022) were associated with 30-day mortality. In the logistic regression analysis, history of chronic kidney disease was diagnosed as a risk factor for 30-day mortality among the PE patients (P = 0.029, odds ratio = 4.93).

Conclusion:

Results of this study showed 30-day mortality was not affected by OSA directly. In fact, it was affected by complications of OSA such as hypertension and thrombus. Also, positive history of chronic kidney disease increased the risk of 30-day mortality.