Association between obstructive sleep apnea and pulmonary embolism

The Association between Obstructive Sleep Apnea and Venous Thromboembolism: A Bidirectional Two-Sample Mendelian Randomization Study

BACKGROUND

 Despite previous observational studies linking obstructive sleep apnea (OSA) to venous thromboembolism (VTE), these findings remain controversial. This study aimed to explore the association between OSA and VTE, including pulmonary embolism (PE) and deep vein thrombosis (DVT), at a genetic level using a bidirectional two-sample Mendelian randomization (MR) analysis.

METHODS

 Utilizing summary-level data from large-scale genome-wide association studies in European individuals, we designed a bidirectional two-sample MR analysis to comprehensively assess the genetic association between OSA and VTE. The inverse variance weighted was used as the primary method for MR analysis. In addition, MR-Egger, weighted median, and MR pleiotropy residual sum and outlier (MR-PRESSO) were used for complementary analyses. Furthermore, a series of sensitivity analyses were performed to ensure the validity and robustness of the results.

RESULTS

 The initial and validation MR analyses indicated that genetically predicted OSA had no effects on the risk of VTE (including PE and DVT). Likewise, the reverse MR analysis did not find substantial support for a significant association between VTE (including PE and DVT) and OSA. Supplementary MR methods and sensitivity analyses provided additional confirmation of the reliability of the MR results.

CONCLUSION

 Our bidirectional two-sample MR analysis did not find genetic evidence supporting a significant association between OSA and VTE in either direction.

Changes in sleep-disordered breathing from the acute to the stable phase of pulmonary embolism: The ESAET study

BACKGROUND

/Objective: Sleep-disordered breathing (SDB) may change from the acute to stable phase of some cardiovascular disorders, but little is known whether these dynamic changes also exist in pulmonary embolism (PE). This study aimed to analyze the changes in the apnea-hypopnea index (AHI) from the acute to stable phase of PE as well as the factors associated.

PATIENTS/METHODS

We conducted a prospective, longitudinal and multicenter study of consecutive adults requiring hospitalization for non-hypotensive acute PE, with a protocol including clinical, imaging (transthoracic echocardiography [TTE] and computed tomography), blood tests and a sleep study within 48 h of diagnosis of PE. After 3 months of follow-up, the sleep study was repeated. Right ventricular (RV) dysfunction was defined according to TTE criteria.

RESULTS

One hundred and eleven patients (mean age [SD]: 63 [15] years; body mass index: 28.4 [4.7] kg/m2) were included. The initial AHI was 24.4 (21.8) events/h (AHI≥5: 82.8 %; AHI≥30: 33.3 %). Seventy-seven patients (69.4 %) had RV dysfunction. In the overall cohort, the AHI decreased by 8.7 events/h from the acute to stable phase (24.4/h vs. 15.7/h; p=0.013). Patients with RV dysfunction showed a greater decrease in AHI (mean decrease 12.3/h vs. 0.43/h). In the multivariable analysis a drop of an AHI≥5 events/hour was independently associated with the presence of initial RV dysfunction (hazard ratio 3.9; 95%CI 1.3 to 12.1).

CONCLUSIONS

In hemodynamically stable patients with acute PE, there is a transient but clinically significant decrease in the AHI from the acute to stable phase, particularly when initially presenting with RV dysfunction.

Obstructive Sleep Apnea as a Risk Factor for Venous Thromboembolism: A Systematic Review

Obstructive sleep apnea (OSA), is a prevalent condition characterized by repeated episodes of pharyngeal airway obstruction resulting in hypopnea and apnea episodes during sleep leading to nightly awakenings. OSA is a major contributor to the healthcare burden worldwide due to its high cardiovascular morbidity and mortality. There is growing evidence to support a pathophysiological link between OSA and venous thromboembolism (VTE). The pro-inflammatory state along with intermittent hypoxia that is invoked in OSA is associated with blood hypercoagulability, venous stasis, and endothelial dysfunction leading to deep vein thrombosis (DVT) and pulmonary embolism (PE). In this systematic review, we aim to analyze and assess the available literature on OSA and VTE (or DVT/PE) to determine whether OSA is an independent risk factor for VTE.

Association between obstructive sleep apnea and venous thromboembolism recurrence: results from a French cohort

Background

Growing evidence suggests the relationship between obstructive sleep apnea (OSA) and venous thromboembolism (VTE). Few studies focused on VTE recurrence risk associated with OSA after anticoagulation cessation.

Methods

In a prospective cohort study, patients with documented VTE, were followed for an indefinite length of time and VTE recurrence were documented and adjudicated. The primary outcome was recurrent VTE after anticoagulation discontinuation. Secondary outcomes included all-cause mortality and the clinical presentation of VTE. Univariable and multivariable analyses were performed to identify risk factors for recurrence and mortality.

Results

Among the 2109 patients with documented VTE included, 74 patients had moderate to severe OSA diagnosis confirmed by home sleep test or polysomnography. During a median follow-up of 4.8 (interquartile range 2.5–8.0) years recurrent VTE occurred in 252 patients (9 with OSA and 243 without OSA). The recurrence risk in the univariable and multivariable analysis was not increased in patients with OSA, regardless of the time of diagnosis (before or after index VTE or pooled). VTE phenotype was significantly more often PE with or without associated deep vein thrombosis in the first event and recurrence for OSA patients compared to non-OSA patients. The risk of death was not increased in the OSA population compared to non-OSA patients in multivariable analysis.

Conclusions

In patients with OSA and VTE, the risk of all-cause mortality and VTE recurrence after anticoagulation discontinuation was not increased compared to non-OSA patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12959-021-00358-8.

Obstructive sleep apnea and stroke: The mechanisms, the randomized trials, and the road ahead

When considered separately from cardiovascular disease, stroke is the third leading cause of death in the U.S. and is the leading cause of long-term disability in adults. New approaches that can be offered to the majority of ischemic stroke patients, can be continued throughout post-stroke care, can limit stroke severity, and can complement or even enhance rehabilitation, would transform ischemic stroke recovery. The treatment of obstructive sleep apnea (OSA) in patients with acute ischemic stroke may represent one such approach. This manuscript reviews the epidemiologic studies of the bidirectional association between OSA and stroke, and the mechanisms and molecular signatures of OSA leading to transient ischemic attack and stroke as well as the randomized controlled trials and observational cohort studies examining continuous positive airway treatment efficacy on the impact of stroke outcomes. Finally, the insights these studies provide on future research are also discussed.

Presence of obstructive sleep apnea is associated with higher future readmissions and outpatient visits-a nationwide administrative dataset study

BACKGROUND

Hospital readmissions and outpatient visits contribute to the significant burden on healthcare systems. Obstructive sleep apnea (OSA) is a chronic medical condition that is associated with cardiovascular comorbidities and other chronic conditions. Inpatient and outpatient healthcare utilization rates in patients with OSA following hospitalization are unclear.

METHODS

This. retrospective case-control cohort study utilized a nationwide database to assess if OSA is associated with higher healthcare utilization post-hospitalization. We compared healthcare utilization among patients with OSA versus without OSA between 2009 and 2014 after matching for demographic variables, geographic location, hospital environment, reason for admission, and severity of illness during hospitalization. We measured future healthcare utilization by the number of ICU admissions, hospital admissions, emergency room visits, and outpatient visits after being discharged from the index hospitalization.

RESULTS

Two equal-sized cohorts comprised of 85,912 matched pairs were obtained. The OSA cohort demonstrated significantly higher rates of future ICU admissions, hospital admissions, emergency room visits, and outpatient visits. Matching for comorbid cardiovascular conditions continued to demonstrate higher healthcare utilization in the OSA group. Short-term outcomes during the index hospitalization were relatively similar between groups.

CONCLUSIONS

This retrospective database study demonstrated that OSA may be an independent marker of higher future healthcare utilization. On the other hand, the length of stay during the index hospitalization was not elevated. Prospective studies are needed to confirm these findings and investigate the impact of directing additional resources to inpatients with OSA.

Sex-differences in the effect of obstructive sleep apnea on patients hospitalized with pulmonary embolism and on in-hospital mortality

We determined sex differences in the prevalence of obstructive sleep apnea (OSA) among patients hospitalized with pulmonary embolism (PE) in Spain (2016–2018). We also compared outcomes according to the presence of OSA, and identified variables associated with in-hospital-mortality (IHM) after PE using the Spanish National Hospital Discharge Database. We identified 46,794 hospital admissions for PE; of these, 5.47% had OSA. OSA was more prevalent among men than women (7.57% vs. 3.65%, p < 0.001), as in the general population. Propensity score matching did not reveal differences in concomitant conditions or procedures between patients with and without OSA, except for the use of non-invasive ventilation, which was more frequent in patients with OSA. IHM was similar in patients with and without OSA (3.58% vs. 4.31% for men and 4.39% vs. 4.93% for women; p > 0.05). Older age, cancer, atrial fibrillation, non-septic shock, and need for mechanical ventilation increased IHM in men and women with OSA hospitalized with PE. The logistic regression model showed no sex differences in IHM among patients with OSA.

Neuropeptide Y: An Update on the Mechanism Underlying Chronic Intermittent Hypoxia-Induced Endothelial Dysfunction

Endothelial dysfunction (ED) is a core pathophysiological process. The abnormal response of vascular endothelial (VE) cells to risk factors can lead to systemic consequences. ED caused by intermittent hypoxia (IH) has also been recognized. Neuropeptide Y (NPY) is an important peripheral neurotransmitter that binds to different receptors on endothelial cells, thereby causing ED. Additionally, hypoxia can induce the release of peripheral NPY; however, the involvement of NPY and its receptor in IH-induced ED has not been determined. This review explains the definition of chronic IH and VE function, including the relationship between ED and chronic IH-related vascular diseases. The results showed that that the effect of IH on VE injury is mediated by the VE-barrier structure and endothelial cell dysfunction. These findings offer new ideas for the prevention and treatment of obstructive sleep apnea syndrome and its complications.

Cardiac Surgery Outcomes: A Case for Increased Screening and Treatment of Obstructive Sleep Apnea

BACKGROUND

Due to the limited published information on complications that obstructive sleep apnea (OSA) patients experience during and after cardiac surgery, we are investigating OSA as a risk factor for post-operative outcomes.

METHODS

This project utilized the Northern New England Cardiovascular Disease Study Group's data collected between 2011 and 2017 based on the Society of Thoracic Surgeons Adult Cardiac Surgery Database Data Collections form. A retrospective analysis of 1,555 patients with OSA and 10,450 patients without OSA, across 5 medical centers undergoing isolated CABG, isolated valve, combined CABG valve surgery was conducted. We used 1:1 nearest neighbor propensity score matching with no replacement to balance characteristics among patients with and without OSA.

RESULTS

There was a statistically significant increased risk of post-operative pneumonia, increased length of total and post-operative stay, and time to initial extubation. Two outcomes trended towards significance: intra- and post-operative IABP use. Outcomes that failed to show statistical significance included: surgical site infection, atrial fibrillation cerebrovascular accident, permanent pacemaker placement, and blood products given. A chart review conducted on a subset of the study cohort revealed that more than 40% of OSA patients did not receive CPAP or BiPAP therapy post-operatively during their hospitalization.

CONCLUSIONS

Our study aligns with the literature in concluding that OSA has deleterious effects on post-operative outcomes of cardiac surgery patients. Further research to better stratify OSA patients by severity are still needed. Additionally, heightened awareness of the need to screen, diagnose, and properly treat patients for OSA is needed.

CB1 receptor antagonist rimonabant protects against chronic intermittent hypoxia-induced renal injury in rats

BACKGROUND

Obstructive sleep apnoea (OSA) induced chronic kidney disease is mainly caused by chronic intermittent hypoxia (CIH). Our study investigate the mechanism underlying CIH-induced renal damage and whether the cannabinoid receptor 1 (CB1R) antagonist rimonabant (Ri) alleviates CIH-induced renal injury.

METHODS

Male Sprague-Dawley rats were randomly divided into five groups: one normal control (NC) group, two chronic intermittent hypoxia (CIH) groups, and two CIH + Ri groups. Rats in the NC groups were exposed to room air, while the CIH groups were exposed to a CIH environment for 4 weeks (4w CIH group) and 6 weeks (6w CIH group), respectively. Additionally, rats in the CIH + Ri groups were administered 1.5 mg/kg/day Ri for 4 weeks (4w CIH + Ri group) and 6 weeks (6w CIH + Ri group), respectively. Following this, the rats were euthanized and kidneys were excised for downstream analysis. In the renal tissues, the morphological alterations were examined via haematoxylin eosin (HE) staining and periodic acid schiff (PAS) staining, CB1R, Fis1, Mfn1, and p66Shc expression was assessed through western blot and immunohistochemistry, and the mitochondrial ultrastructural changes in kidney sections were assessed by electron microscopy.

RESULTS

CB1R expression in the 4w and 6w CIH groups was significantly elevated, and further increased with prolonged hypoxia; however, Ri prevented the increase in CIH-induced CB1R expression. Fis1 and p66Shc expression in the CIH groups were increased, but Mfn1 expression decreased. Ri decreased Fis1 and p66Shc expression and increased Mfn1 expression. Renal damage in the 4w or 6w CIH + Ri group was evidently improved compared with that in the 4w or 6w CIH group. CB1R expression was positively correlated with Fis1 and p66Shc and negatively correlated with Mfn1. Meanwhile, electron microscopy showed that the percentage of fragmented mitochondria in the tubular cells in each group was consistent with the trend of CB1R expression.

CONCLUSION

CIH causes endocannabinoid disorders and induces abnormal mitochondrial dynamics, resulting in renal injury. Treatment with CB1R antagonists reduces CIH-induced renal damage by inhibiting dysregulated renal mitochondrial dynamics.

Influence of Intermittent Hypoxia/Hypercapnia on Atherosclerosis, Gut Microbiome, and Metabolome

Obstructive sleep apnea (OSA), a common sleep disorder characterized by intermittent hypoxia and hypercapnia (IHC), increases atherosclerosis risk. However, the contribution of intermittent hypoxia (IH) or intermittent hypercapnia (IC) in promoting atherosclerosis remains unclear. Since gut microbiota and metabolites have been implicated in atherosclerosis, we examined whether IH or IC alters the microbiome and metabolome to induce a pro-atherosclerotic state. Apolipoprotein E deficient mice (ApoE-/- ), treated with IH or IC on a high-fat diet (HFD) for 10 weeks, were compared to Air controls. Atherosclerotic lesions were examined, gut microbiome was profiled using 16S rRNA gene amplicon sequencing and metabolome was assessed by untargeted mass spectrometry. In the aorta, IC-induced atherosclerosis was significantly greater than IH and Air controls (aorta, IC 11.1 ± 0.7% vs. IH 7.6 ± 0.4%, p < 0.05 vs. Air 8.1 ± 0.8%, p < 0.05). In the pulmonary artery (PA), however, IH, IC, and Air were significantly different from each other in atherosclerotic formation with the largest lesion observed under IH (PA, IH 40.9 ± 2.0% vs. IC 20.1 ± 2.6% vs. Air 12.2 ± 1.5%, p < 0.05). The most differentially abundant microbial families (p < 0.001) were Peptostreptococcaceae, Ruminococcaceae, and Erysipelotrichaceae. The most differentially abundant metabolites (p < 0.001) were tauro-β-muricholic acid, ursodeoxycholic acid, and lysophosphoethanolamine (18:0). We conclude that IH and IC (a) modulate atherosclerosis progression differently in distinct vascular beds with IC, unlike IH, facilitating atherosclerosis in both aorta and PA and (b) promote an atherosclerotic luminal gut environment that is more evident in IH than IC. We speculate that the resulting changes in the gut metabolome and microbiome interact differently with distinct vascular beds.

Outcomes of patients hospitalized for acute pulmonary embolism by obstructive sleep apnea status

Pulmonary embolism (PE) is a major cause of cardiovascular morbidity and mortality. Obstructive sleep apnea (OSA) is increasingly recognized in the aging population, especially with the rising obesity epidemic. The impact of OSA on inpatient mortality in PE is not well understood. We used the Nationwide Inpatient Sample databases from 2005 to 2016 to identify 755,532 acute PE patients (age≥18 years). Among these, 61,050 (8.1%) were OSA+. Temporal trends in length of stay, inpatient mortality, and its association with OSA in PE patients were analyzed. The proportion of PE patients who were OSA+ increased from 2005 to 2016. OSA+ PE patients were younger and predominantly men. Despite a higher prevalence of traditional risk factors for inpatient mortality in OSA+ patients, OSA was associated with a lower risk of mortality in PE patients (odds ratio, 95% confidence interval; p: unadjusted 0.56, 0.53–0.58; p < 0.0001 and adjusted 0.55, 0.52–0.58; p < 0.0001). Overall mortality and length of stay in PE patients decreased over time. Relative to OSA– patients, there was a slight increase in mortality among OSA+ PE patients over time, although the length of stay remained unchanged between the two groups. In conclusion, OSA+ PE patients had a lower inpatient mortality compared to OSA– patients despite a higher prevalence of traditional mortality risk factors. Secondary pulmonary hypertension related to OSA with preconditioning of the right ventricle to elevated afterload may potentially explain the protective effect of OSA on mortality in PE. However, mechanistic studies need to further elucidate the links behind this association.

Prognostic Impact of Obstructive Sleep Apnea in Patients Presenting with Acute Symptomatic Pulmonary Embolism

BACKGROUND

 In patients with pulmonary embolism (PE), there is a lack of comprehensive data on the prevalence and prognostic significance of pre-existing obstructive sleep apnea (OSA).

METHODS

 In this study of patients with PE from the Registro Informatizado de la Enfermedad TromboEmbólica (RIETE) registry, we assessed the prevalence of OSA, and the association between pre-existing OSA and the outcomes of all-cause mortality, PE-related mortality, recurrences, and major bleeding over 30 days after initiation of PE treatment. Additionally, we also examined rates of outcomes within 90 days and 1 year following the diagnosis of PE.

RESULTS

 Of 4,153 patients diagnosed with PE, 241 (5.8%; 95% confidence interval [CI]: 5.1-6.6%) had pre-existing OSA. Overall, 166 (4.0%; 95% CI: 3.4-4.6%) died during the first 30 days of follow-up. In multivariable analysis, the OSA syndrome was not a significant predictor of death from any cause (odds ratio [OR]: 1.5; 95% CI: 0.8-2.9; p = 0.19). However, patients with pre-existing OSA had an increased PE-specific mortality (adjusted OR: 3.0; 95% CI: 1.3-6.8; p = 0.01) compared with those without OSA. OSA was not significantly associated with 30-day recurrent venous thromboembolism (adjusted OR: 0.6; 95% CI: 0.1-4.7; p = 0.65) or major bleeds (adjusted OR: 1.0; 95% CI: 0.4-2.2; p = 1.0). Findings were similar at 90-day and 1-year follow-ups.

CONCLUSION

 In patients presenting with PE, pre-existing OSA is relatively infrequent. Patients with OSA were at increased risk of PE-related mortality when compared with those without OSA.

Assessment of the frequency of deep venous thromboembolism in obstructive sleep apnea syndrome

The present study aimed to investigate the frequency of deep venous thrombosis (DVT) among patients with obstructive sleep apnea syndrome (OSAS). Patients who referred the preliminary diagnosis of OSAS were included in this study. D-dimer levels of all patients were measured, and D-dimer (+) patients were evaluated by Doppler USG of the lower-extremity. Mean age of the patient group was 52 ± 12 years and 31.8% (76/239) were women. The rate of D-dimer positivity among severe-OSAS cases (15/85) was significantly higher compared to the rest (13/154) (17.6% and 8.4%, respectively; p = 0.034). The risk of D-dimer positivity was elevated by 2.3 folds in severe-OSAS cases (OR: 2,324, 95% confidence interval: 1.048-5.152). Among 28 D-dimer (+) cases, 4 (14.2%) had DVT as demonstrated by USI of the lower-extremity. All four cases with DVT had severe OSAS. D-dimer was positive in 17.6% (15/85) of all severe OSAS cases. DVT was diagnosed in 4.7% (4/85) of severe-OSAS cases. DVT frequency was 26.6% (4/15) in D-dimer (+) severe-OSAS. Findings of this study indicate that severe-OSAS can be a significant risk factor for DVT. Additionally, data obtained in this study underline the benefits of questioning severe-OSAS patients with respect to DVT symptoms, investigating D-dimer levels and evaluating D-dimer (+) severe-OSAS cases for DVT prophylaxis.

The role of obstructive sleep apnea on the prognosis of pulmonary embolism: a systemic review and meta-analysis

PURPOSE

The relationship between obstructive sleep apnea (OSA) and pulmonary embolism (PE) has been reported by some studies but the underlying mechanism remains unclear. We aimed to systematically assess the role of OSA on the disease prognosis of PE.

METHODS

We searched for studies on the relationship of OSA and the prognosis of PE published up to February 2020 among PubMed, Web of Science, EMBASE, and Cochrane Library databases. Two independent reviewers conducted the process of study search and screening, quality assessment, and data extraction. Meta-analysis was carried out using RevMan 5.3.

RESULTS

A total of 9 articles were included, and the funnel plots suggested no evidence of publication bias among studies. The results showed that compared to PE patients without OSA, the PE patients with moderate-severe OSA were more likely to be high-risk type (OR = 1.96, 95% CI [1.14, 3.34]) and with higher index of disease severity (sPESI: OR = 2.29, 95% CI [1.50, 3.47]; PAOI%: MD = 13.52, 95% CI [7.2, 19.83]). The prevalence of recurrent PE was higher in PE patients with OSA than those without OSA (RR = 3.87, 95% CI [1.65, 9.07]). However, there was no significant difference in right ventricle to left ventricle short-axis diameter (MD = 0.08, 95% CI [- 0.06, 0.21]), length of hospital stay (MD = 1.03, 95% CI [- 1.11, 3.17]), or prevalence of deep vein thrombosis (OR = 0.87, 95% CI [0.48, 1.57]). Sensitivity and subgroup analysis showed that the pooled outcomes were stable.

CONCLUSION

OSA, especially moderate-severe OSA, was a risk factor for high-risk PE and recurrent PE. However, the current evidence showed that the length of hospital stay is not influenced by OSA.

Impact of sleep apnoea-hypopnoea syndrome on diabetic neuropathy. A systematic review

INTRODUCTION

Diabetes mellitus and sleep apnoea-hypopnoea syndrome appear to be related, but it is not well defined whether there is an increased risk of peripheral neuropathy in patients with both diseases. For this reason, we conducted a systematic review.

METHODS

Bibliographic search in 3 electronic databases using a predefined strategy and the PRISMA methodology. Only original studies (any type of design) published from 2000 onwards in English, French, Portuguese or Spanish were included. A study quality scale was established.

RESULTS

Twelve articles were selected, of which six studied type 2 diabetic patients. The overall prevalence of sleep apnoea-hypopnoea syndrome was 43.7% (1,559/3,564 patients). Diabetic neuropathy was more frequent in patients with sleep apnoea-hypopnoea syndrome in nine studies, although significantly only in four (60% vs 27%, P<.001; 64.5% vs 36%, P=.03; 37% vs 23.4%, P<.02; 66.6% vs 0%, P=.007). In one study, diabetic neuropathy was more frequent in patients without sleep apnoea-hypopnoea syndrome (although not statistically significant) and in 2 no comparison was made between patients with/without sleep apnoea/hypopnoea syndrome.

CONCLUSIONS

The observed results suggest a relationship between diabetes mellitus and sleep apnoea-hypopnoea syndrome in the occurrence of diabetic neuropathy.

Intermittent hypoxia and hypercapnia induces inhibitor of nuclear factor-κB kinase subunit β-dependent atherosclerosis in pulmonary arteries

Clinical studies have shown that obstructive sleep apnea (OSA) increases atherosclerosis risk. The inflammation, especially mediated by the macrophages via nuclear factor-κB (NF-κB), has been speculated to contribute to atherogenicity in OSA patients. Inhibitor of NF-κB kinase-β (IKKβ) is an essential element of the NF-κB pathway and is linked to atherosclerosis. We previously reported that atherosclerosis was accelerated in pulmonary artery (PA) but not in aorta when low-density lipoprotein receptor knockout (Ldlr-/-) mice were exposed to intermittent hypoxia/hypercapnia (IHH), a surrogate for recurrent upper-airway obstruction. Therefore, we hypothesized that IKKβ-dependent NF-κB activation in monocytes and macrophages plays a role in IHH-induced PA atherosclerosis. To test this hypothesis, myeloid restricted IKKβ deletion (IkkβΔMye) or control (IkkβF/F) mice were crossed with Ldlr-/- mice to generate double-knockout mice. Then, the mice were exposed to IHH or room air (Air) on high-fat diet for 8 or 16 wk. Lesions of PA and aorta were examined in IkkβΔMye;Ldlr-/- and IkkβF/F;Ldlr-/- male mice under IHH vs. Air. The results revealed that IKKβ deletion abolished IHH-induced PA atherosclerosis after 8-wk exposure but not after 16-wk exposure (8 wk: IkkβF/F;Ldlr-/-, IHH 13.5 ± 1.4 vs. Air 5.7 ± 0.7%, P < 0.01; IkkβΔMye;Ldlr-/-, IHH 7.4 ± 1.9% vs. Air 4.6 ± 1.3%, P = 0.24). Both IKKβ deletion and IHH had no effects on atherosclerosis in the aorta. Our findings demonstrate that IKKβ-dependent NF-κB activity in myeloid-lineage cells plays a critical role in IHH-induced PA atherosclerosis at the early stage.

Obstructive sleep apnea and venous thromboembolism: Overview of an emerging relationship

Obstructive sleep apnea (OSA) is a risk factor for cardiovascular syndromes. Venous thromboembolism (VTE) is a chronic disease, and pulmonary embolism (PE) is the major expression of VTE and the third most frequent cardiovascular disease. An increasing and emerging number of cross-sectional and longitudinal studies have linked OSA to VTE, and have postulated different putative pathways to explain how OSA might increase the risk of PE. We aim to provide a critical overview of the existing evidence about the complex relationship between these two conditions, with some factors and confounding variables still to be clarified. A global interpretation of the studies shows OSA is highly prevalent in VTE patients. This association represents a major public health burden, given the high prevalence and the mortality rates of both disorders. Although still not proven, OSA may induce a persistent hypercoagulable state that may contribute to increase VTE rate and its recurrence. Coagulant activity, platelet function and fibrinolytic system may improve after continuous positive airway pressure (CPAP) in OSA. However, there is a still a lack of randomized controlled trials to evaluate the potential of CPAP and/or extend oral anticoagulation to reduce PE incidence, recurrence and mortality by PE in patients with OSA.

Prevalence of obstructive sleep apnea in venous thromboembolism: a systematic review and meta-analysis

PURPOSE

Previous studies revealed that the concomitant prevalence of obstructive sleep apnea (OSA) and venous thromboembolism (VTE) was high, but the results were inconclusive due to various limitations. We aimed to systematically review the literature on the prevalence of OSA in patients with VTE.

METHODS

Relevant studies were identified on multiple electronic databases through July 2018. The DerSimonian-Laird random effects model was used to calculate the pooled prevalence of OSA, moderate-to-severe OSA, and severe OSA in VTE patients, respectively. Sensitivity analysis was performed based on diagnostic methods of OSA and races.

RESULTS

A total of 11 studies comprising 895 patients were available for the meta-analysis, but one study was excluded because of the between-study heterogeneity in the following analysis. The pooled prevalence of OSA, moderate-to-severe OSA, and severe OSA in VTE patients were 70% (95% CI = 65%, 75%), 41% (95% CI = 29%, 54%), and 19% (95% CI = 15%, 23%), respectively. Sensitivity analysis indicated that the prevalence was similar in different diagnostic methods, but the contributions of races to OSA were complex. Although the lower prevalence of all OSA and moderate-to-severe OSA as compared with Western countries, Asian countries have similar or even a little bit higher prevalence of severe OSA.

CONCLUSIONS

Findings from this meta-analysis supported that the prevalence of OSA in VTE patients was strikingly high. Screening for OSA in patients with VTE is necessary for developing effective treatment strategies.

Obstructive sleep apnoea and venous thromboembolism: pathophysiological links and clinical implications

Obstructive sleep apnoea (OSA) and pulmonary embolism (PE) remain major health issues worldwide. Data from pathophysiological studies suggest that both intermittent hypoxia and sleep fragmentation are associated with increased blood coagulability, endothelial dysfunction and venous stasis. There is growing evidence that OSA is potentially prevalent in and a risk factor for PE. Conversely, patients with acute PE have two to four times greater risk of moderate-to-severe OSA. The role of continuous positive airway pressure (CPAP) treatment in improving clinically meaningful outcomes in PE patients remains unclear, although some authors have suggested that CPAP could improve the hypercoagulability state and normalise circadian alterations in some of the coagulation molecules, as observed in patients with OSA. Emerging research highlights the complex interdependent relationships between OSA and PE, emphasising the need for rigorous, well-powered trials that address the impact of OSA and its treatment on the prevention and management of PE. Undoubtedly, these will require closer collaboration between the sleep medicine and clinical/venous thromboembolism communities.

Sleep apnea in total joint arthroplasty patients and the role for cardiac biomarkers for risk stratification: an exploration of feasibility

Obstructive sleep apnea (OSA) is highly prevalent in patients undergoing total joint arthroplasty (TJA) and is a major risk factor for postoperative cardiovascular complications and death. Recognizing this, the American Society of Anesthesiologists urges clinicians to implement special considerations in the perioperative care of OSA patients. However, as the volume of patients presenting for TJA increases, resources to implement these recommendations are limited. This necessitates mechanisms to efficiently risk stratify patients having OSA who may be susceptible to post-TJA cardiovascular complications. We explore the role of perioperative measurement of cardiac troponins (cTns) and brain natriuretic peptides (BNPs) in helping determine which OSA patients are at increased risk for post-TJA cardiovascular-related morbidity.

Sleep disordered breathing in pregnancy: the maternal and fetal implications

Sleep disordered breathing (SDB) which includes obstructive sleep apnoea (OSA) and upper airway resistance syndrome (UARS), has emerged as a risk factor for adverse maternal-foetal outcomes in pregnancy. Physiological changes of pregnancy predispose a woman 'at risk' towards developing SDB. The increasing incidence of OSA in pregnancy closely correlates with the population trends of obesity. Common screening tools validated in non-pregnant subjects including Epworth Sleepiness Scale (ESS) and Berlin Questionnaire (BQ) are poor predictors of SDB in pregnancy. Preeclampsia, gestational hypertension and gestational diabetes mellitus (GDM) are linked with SDB. Preeclampsia and OSA share common pathological associations. It is unclear if one predisposes the other. Foetal morbidity includes intrauterine growth restriction (IUGR), preterm delivery, low birth weight, neonatal intensive care unit (NICU) admission and Apgar score of less than seven at one minute. Continuous positive airway pressure (CPAP) is a well-documented treatment of SDB in pregnancy and has been shown to reverse some of the adverse events. It becomes imperative to diagnose and manage this condition as OSA causes substantial morbidity in the untreated pregnant patient and foetus. Three short clinical cases and a literature review on SDB on pregnancy are presented.

Obstructive Sleep Apnea Hypopnea Syndrome as a Reason for Active Management of Pulmonary Embolism

Background:

Obstructive sleep apnea hypopnea syndrome (OSAHS) constitutes an independent factor for high warfarin dose for patients with pulmonary embolism (PE). The aim of this study was to investigate whether the 6-month anticoagulation treatment by warfarin is enough for patients with PE complicated by OSAHS.

Methods:

We investigated 97 PE patients, 32 of them had OSAHS and 65 non-OSAHS. Warfarin was administered for 6-month if no abnormal circumstances occurred. All patients were followed up for 18 months. Adverse events (AE) included death, major bleeding, hospitalization due to heart failure or pulmonary hypertension, and recurrence or aggravation of PE (including deep vein thrombosis). Recurrence rate of PE after warfarin cessation was compared between the two groups.

Results:

OSAHS patients required a significantly higher dose of warfarin than their non-OSAHS counterparts (4.73 mg vs. 3.61 mg, P < 0.001). During warfarin treatment, no major bleeding and aggravation of PE occurred among OSAHS patients, and the rates of various AE were not significantly different between the OSAHS and non-OSAHS groups. PE recurrence was higher in OSAHS than non-OSAHS groups after withdrawal of warfarin (21.43% vs. 6.78%, P = 0.047). Compared with non-OSAHS patients, OSAHS group had lower international normalized ratio (INR) value but higher plasminogen on baseline and INR resumed to a relatively low level after warfarin discontinuation.

Conclusions:

OSAHS patients may present with hypercoagulation and relatively high-risk of recurrence of PE after cessation of 6-month warfarin treatment.

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.

High D-dimer levels after stopping anticoagulants in pulmonary embolism with sleep apnoea

Obstructive sleep apnoea is a risk factor for pulmonary embolism. Elevated D-dimer levels and other biomarkers are associated with recurrent pulmonary embolism. The objectives were to compare the frequency of elevated D-dimer levels (>500 ng·mL−1) and further coagulation biomarkers after oral anticoagulation withdrawal in pulmonary embolism patients, with and without obstructive sleep apnoea, including two control groups without pulmonary embolism.

We performed home respiratory polygraphy. We also measured basic biochemical profile and haemogram, and coagulation biomarkers (D-dimer, prothrombin fragment 1+2, thrombin-antithrombin complex, plasminogen activator inhibitor 1, and soluble P-selectin).

64 (74.4%) of the pulmonary embolism cases and 41 (46.11%) of the controls without pulmonary embolism had obstructive sleep apnoea. Plasmatic D-dimer was higher in PE patients with OSA than in those without obstructive sleep apnoea. D-dimer levels were significantly correlated with apnoea–hypopnoea index, and nocturnal hypoxia. There were more patients with high D-dimer after stopping anticoagulants in those with pulmonary embolism and obstructive sleep apnoea compared with PE without obstructive sleep apnoea (35.4% versus 19.0%, p=0.003). Apnoea–hypopnoea index was independently associated with high D-dimer.

Pulmonary embolism patients with obstructive sleep apnoea had higher rates of elevated D-dimer levels after anticoagulation discontinuation for pulmonary embolism than in patients without obstructive sleep apnoea and, therefore, higher procoagulant state that might increase the risk of pulmonary embolism recurrence.

Sleep, death, and the heart

Obstructive and central sleep apnea have been associated with increased risk of adverse cardiovascular events and mortality. Sympathetic dysregulation occurring as a result of the respiratory disturbance is thought to play a role in this increased risk. Sleep apnea increases the risk of arrhythmias, myocardial ischemia/infarction, stroke, and heart failure, all of which may increase mortality risk. A higher incidence of nocturnal arrhythmias, cardiac ischemia, and sudden death has been noted in subjects with sleep-disordered breathing (SDB). In this review, the association between SDB and each of these conditions is discussed, as well as the potential mechanisms underlying these risks and the effects of treatment of SDB. Particular emphasis is placed on the relationship between SDB and nocturnal atrial and ventricular arrhythmias, myocardial ischemia/infarction and sudden death.

Sleep apnea and venous thromboembolism. A systematic review

Recent evidence suggests that obstructive sleep apnea is a significant and independent risk factor for a number of cardiovascular disorders. Since the association between obstructive sleep apnea and cardiovascular disease is mediated by endothelial dysfunction, hypercoagulability and platelet abnormalities, we sought to investigate whether sleep apnea may also be considered a risk factor for venous thromboembolism (VTE). We carried out an electronic search in Medline and Scopus using the keywords "apnea" OR "apnoea" AND "venous thromboembolism" OR "deep vein thrombosis" OR "pulmonary embolism" in "Title/Abstract/Keywords", with no language or date restriction. Fifteen studies (8 case-control, 4 retrospective observational, 2 prospective case-control and 1 prospective observational) were finally selected for this systematic review. In all studies except one (14/15; 93 %), obstructive sleep apnea was found to be an independent risk factor for VTE, either deep-vein thrombosis (DVT) or pulmonary embolism (PE). In the two prospective case-control studies the risk of DVT or PE was found to be two- to three-fold higher in patients with obstructive sleep apnea than in those without. In conclusion, the current epidemiological evidence supports the hypothesis that obstructive sleep apnea may be an independent risk factor for VTE.

Sleep apnea-hypopnea syndrome and type 2 diabetes. A reciprocal relationship?

Epidemiological data suggest that sleep apnea-hypopnea syndrome (SAHS) is independently associated with the development of insulin resistance and glucose intolerance. Moreover, despite significant methodological limitations, some studies report a high prevalence of SAHS in patients with type 2 diabetes mellitus (DM2). A recent meta-analysis shows that moderate-severe SAHS is associated with an increased risk of DM2 (relative risk=1.63 [1.09 to 2.45]), compared to the absence of apneas and hypopneas. Common alterations in various pathogenic pathways add biological plausibility to this relationship. Intermittent hypoxia and sleep fragmentation, caused by successive apnea-hypopnea episodes, induce several intermediate disorders, such as activation of the sympathetic nervous system, oxidative stress, systemic inflammation, alterations in appetite-regulating hormones and activation of the hypothalamic-pituitary-adrenal axis which, in turn, favor the development of insulin resistance, its progression to glucose intolerance and, ultimately, to DM2. Concomitant SAHS seems to increase DM2 severity, since it worsens glycemic control and enhances the effects of atherosclerosis on the development of macrovascular complications. Furthermore, SAHS may be associated with the development of microvascular complications: retinopathy, nephropathy or diabetic neuropathy in particular. Data are still scant, but it seems that DM2 may also worsen SAHS progression, by increasing the collapsibility of the upper airway and the development of central apneas and hypopneas.

Association between obstructive sleep apnea and deep vein thrombosis / pulmonary embolism: a population-based retrospective cohort study

BACKGROUND

Obstructive sleep apnea (OSA) is a major contributor to cardiovascular disease, and may cause severe morbidity and mortality. Recent studies have indicated that OSA patients exhibited elevated platelet activity, fibrinogen levels, and platelet aggregation.

OBJECTIVES

We investigated the risk of deep vein thrombosis (DVT) and pulmonary embolism (PE) in patients diagnosed with OSA compared with age- and sex-matched unaffected people.

PATIENTS/METHODS

This longitudinal, nationwide, population-based cohort study was conducted using data from Taiwan National Health Insurance Research Database (NHIRD) recorded between January 2000 and December 2011. The study consisted of 3511 patients with OSA and 35110 matched comparison individuals. A Cox proportional hazard regression was used to compute the risk of DVT and PE in patients with OSA compared with those without OSA.

RESULTS

The DVT and PE risks were 3.50- and 3.97-fold higher (95% CI=1.83-6.69 and 1.85-8.51) respectively, in the OSA cohort than in the reference cohort after we adjusted for age, sex, and comorbidities.

CONCLUSION

This nationwide population-based cohort study indicates that patients with OSA exhibit a higher risk of subsequent DVT and PE.