Obstructive Sleep Apnea Affecting Platelet Reactivity in Patients Undergoing Percutaneous Coronary Intervention

Day-night pattern of acute ST-segment elevation myocardial infarction onset in patients with obstructive sleep apnea

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is associated with acute nocturnal hemodynamic and neurohormonal abnormalities that may increase the risk of coronary events, especially during the nighttime. This study sought to investigate the day-night pattern of acute ST-segment elevation myocardial infarction (STEMI) onset in patients with OSA and its impact on cardiovascular adverse events.

METHODS

We prospectively enrolled 397 patients with STEMI, for which the time of onset of chest pain was clearly identified. All participants were categorized into non-OSA (n = 280) and OSA (n = 117) groups. The association between STEMI onset time and major adverse cardiovascular and cerebrovascular events was estimated by Cox proportional hazards regression.

RESULTS

STEMI onset occurred from midnight to 5:59 am in 33% of patients with OSA, as compared with 15% in non-OSA patients (P < .01). For individuals with OSA, the relative risk of STEMI from midnight to 5:59 am was 2.717 [95% confidence interval (CI) 1.616 - 4.568] compared with non-OSA patients. After a median of 2.89 ± 0.78 years follow-up, symptom onset time was found to be significantly associated with risk of major adverse cardiovascular and cerebrovascular events in patients with OSA, while there was no significant association observed in non-OSA patients. Compared with STEMI presenting during noon to 5:59 pm, the hazard ratios for major adverse cardiovascular and cerebrovascular events in patients with OSA were 4.683 (95% CI 2.024 - 21.409, P = .027) for midnight to 5:59 am and 6.964 (95% CI 1.379 - 35.169, P = .019) for 6 pm to midnight, whereas the hazard ratios for non-OSA patients were 1.053 (95% CI 0.394 - 2.813, P = .917) for midnight to 5:59 am and 0.745 (95% CI 0.278 - 1.995, P = .558) for 6 pm to midnight.

CONCLUSIONS

Patients with OSA exhibited a peak incidence of STEMI between midnight and 5:59 am, which showed an independent association with cardiovascular adverse events.

CITATION

Wang Y, Buayiximu K, Zhu T, et al. Day-night pattern of acute ST-segment elevation myocardial infarction onset in patients with obstructive sleep apnea. J Clin Sleep Med. 2024;20(5):765-775.

The Use of Aspirin Increases the Risk of Major Adverse Cardiac and Cerebrovascular Events in Hypertensive Patients with Obstructive Sleep Apnea for the Primary Prevention of Cardiovascular Disease: A Real-World Cohort Study

(1) Background: Hypertensive patients with obstructive sleep apnea (OSA) are at high risk for cardiovascular diseases (CVDs), and the utility of aspirin for primary cardiovascular prevention in this population remains uncertain. (2) Methods: In this retrospective cohort study using data from the Urumchi Hypertension Database (UHDATA), hypertensive patients older than 18 years old with a first-time diagnosis of OSA were divided into three groups depending on aspirin history. Major adverse cardiac and cerebrovascular events (MACCE) were the primary outcome. Secondary outcomes included MACCE components, ischemic events, cardiac events, cerebrovascular events, and gastrointestinal bleeding risk. The inverse probability of treatment weighting (IPTW) method was used to balance the confounding factors among the groups, and the Cox proportional hazards model was used to calculate the hazard ratio (HR) and 95% confidence interval (CI). (3) Results: In persistent aspirin users, the risk of MACCE events (HR 2.11, 95%CI 1.23-3.63), ischemic events (HR 2.58, 95%CI 1.42-4.69), cerebrovascular events (HR 2.55, 95%CI 1.44-4.51), and non-fatal cerebral infarction (HR 3.14, 95%CI 1.69-5.84) was significantly elevated. (4) Conclusions: Continuous aspirin use increases the incidence of cardiovascular adverse events in hypertensive patients with OSA receiving aspirin for primary prevention of cardiovascular disease.

The interaction among OSA, CPAP, and medications in patients with comorbid OSA and cardiovascular/cerebrovascular disease: a randomized controlled trial

BACKGROUND

Most patients with comorbid sleep apnea (OSA), cardiovascular (CV) disease, and/or cerebrovascular (CeV) disease simultaneously take medications. Whether OSA and continuous positive airway pressure (CPAP) interact with CV/CeV medications remains unknown. This study aimed to determine the interaction among OSA, CPAP, and CV/CeV medications; the effects of medications on major adverse cardiac and cerebrovascular events, and survival in patients with comorbid OSA and CV/CeV.

METHODS

This was a post hoc analysis of the data from one center of the Sleep Apnea Cardiovascular Endpoints Study. Participants (aged 45-75 years) with comorbid OSA and CV/CeV were randomized to receive usual care with or without CPAP from December 2008 to November 2013. The primary endpoint was death and the secondary endpoint was a composite of death, myocardial infarction, stroke, hospitalization for unstable angina, heart failure, and transient ischemic attack.

RESULTS

In total, 131 patients were analyzed. Sixty-three were in the CPAP group and 68 were in the usual care group, 41 had good adherence to CPAP (65.1%), and the median follow-up time was 43.0 (35.0, 54.0) months. In Cox regression analysis, ACE inhibitors and nitrates were independent factors for decreased survival in patients with comorbid OSA and CV/CeV (chi-square = 22.932, P = 0.003; ACE inhibitors: OR 7.241, P = 0.048, 95% CI 1.016-51.628; nitrates: OR 18.012, P = 0.011, 95% CI 1.923-168.750). ACE inhibitors increased mortality and secondary endpoints in the CPAP group (chi-square = 4.134, P = 0.042) but not in patients with good CPAP adherence. Clopidogrel and nitrates decreased survival in usual care group (clopidogrel: chi-square = 5.312, P = 0.021; nitrates: chi-square = 6.417, P = 0.011), but not in CPAP group.

CONCLUSIONS

OSA may predispose patients with CV/CeV and CV/CeV medications to a negative effect. CPAP treatment may neutralize the negative effects of OSA by relieving chronic intermittent hypoxia. Trial registration ClinicalTrials.gov (NCT00738179, first registration date: 20/08/2008).

Diagnostic Value of the Neutrophil-to-Lymphocyte Ratio (NLR) and Platelet-to-Lymphocyte Ratio (PLR) in Various Respiratory Diseases: A Retrospective Analysis

The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte (PLR) ratio are two extensively used inflammatory markers that have been proved very useful in evaluating inflammation in several diseases. The present article aimed to investigate if they have any value in distinguishing among various respiratory disorders. One hundred and forty-five patients with coronavirus disease 2019 (COVID-19), 219 patients with different chronic respiratory diseases (interstitial lung disease, obstructive sleep apnea(OSA)-chronic obstructive pulmonary disease (COPD) overlap syndrome, bronchiectasis) and 161 healthy individuals as a control group were included in the study. While neither NLR nor PLR had any power in differentiating between various diseases, PLR was found to be significant but poor as a diagnostic test when the control group was compared with the OSA-COPD group. NLR was found to be significant but poor as a diagnostic test when we compared the control group with all three groups (separately): the OSA-COPD group; interstitial lung disease group, and bronchiectasis group. NLR and PLR had poor power to discriminate between various respiratory diseases and cannot be used in making the differential diagnosis.

Obstructive Sleep Apnea, Hypercoagulability, and the Blood-Brain Barrier

Obstructive sleep apnea (OSA) is characterized by repeated episodes of intermittent hypoxia (IH) and is recognized as an independent risk factor for vascular diseases that are mediated by a multitude of mechanistic pathophysiological cascades including procoagulant factors. The pro-coagulant state contributes to the development of blood clots and to the increase in the permeability of the blood-brain barrier (BBB). Such alteration of BBB may alter brain function and increase the risk of neurodegenerative diseases. We aim to provide a narrative review of the relationship between the hypercoagulable state, observed in OSA and characterized by increased coagulation factor activity, as well as platelet activation, and the underlying neural dysfunction, as related to disruption of the BBB. We aim to provide a critical overview of the existing evidence about the effect of OSA on the coagulation balance (characterized by increased coagulation factor activity and platelet activation) as on the BBB. Then, we will present the emerging data on the effect of BBB disruption on the risk of underlying neural dysfunction. Finally, we will discuss the potential of OSA therapy on the coagulation balance and the improvement of BBB.

Cardiovascular Disorders Triggered by Obstructive Sleep Apnea-A Focus on Endothelium and Blood Components

Obstructive sleep apnea (OSA) is known to be an independent cardiovascular risk factor. Among arousal from sleep, increased thoracic pressure and enhanced sympathetic activation, intermittent hypoxia is now considered as one of the most important pathophysiological mechanisms contributing to the development of endothelial dysfunction. Nevertheless, not much is known about blood components, which justifies the current review. This review focuses on molecular mechanisms triggered by sleep apnea. The recurrent periods of hypoxemia followed by reoxygenation promote reactive oxygen species (ROS) overproduction and increase inflammatory response. In this review paper we also intend to summarize the effect of treatment with continuous positive airway pressure (CPAP) on changes in the profile of the endothelial function and its subsequent potential clinical advantage in lowering cardiovascular risk in other comorbidities such as diabetes, atherosclerosis, hypertension, atrial fibrillation. Moreover, this paper is aimed at explaining how the presence of OSA may affect platelet function and exert effects on rheological activity of erythrocytes, which could also be the key to explaining an increased risk of stroke.

Association Between Obstructive Sleep Apnea-Hypopnea Syndrome and Outcomes in Patients With Myocardial Infarction in the Absence of Obstructive Coronary Artery Disease

Background and Aims: Myocardial infarction in the absence of obstructive coronary artery disease (MINOCA) occurs in 5-10% of all patients with acute myocardial infarction. Obstructive sleep apnea-hypopnea syndrome (OSAHS) is linked to increased cardiovascular morbidity and mortality, but the relationship of OSAHS and outcomes in patients with MINOCA remains unknown. We aimed to evaluate the association between OSAHS and clinical outcomes in patients with MINOCA. Methods: Between January 2015 and December 2016, we carried out a consecutive cohort study of 583 patients with MINOCA and followed them up for 3 years. An apnea-hypopnea index of ≥ 15 events per hour recorded by polysomnography was defined as the diagnostic criterion for OSAHS. The primary end point was all-cause mortality, and the second end point was major adverse cardiovascular or cerebrovascular events (MACCE), a composite of cardiac death, non-fatal myocardial infarction, heart failure, cardiovascular-related rehospitalization, and stroke. Results: All-cause mortality happened in 69 patients and MACCE occurred in 113 patients during the 3-year follow-up. Kaplan-Meier survival curves indicated the significant relationship of OSAHS with all-cause mortality (log-rank P = 0.012) and MACCE (log-rank P = 0.002). Multivariate Cox regression analysis indicated OSAHS as an independent predictor of all-cause mortality and MACCE [adjusted hazard ratio: 1.706; 95% confidence interval (CI): 1.286-2.423; P = 0.008; and adjusted hazard ratio: 1.733; 95% CI: 1.201-2.389; P < 0.001; respectively], independent of age, sex, cardiovascular risk factors and discharge medications. Conclusions: OSAHS is independently associated with increased risk of all-cause mortality and MACCE in patients with MINOCA. Intervention and treatment should be considered to alleviate OSAHS-associated risk.

Obstructive Sleep Apnea: From Intermittent Hypoxia to Cardiovascular Complications via Blood Platelets

Obstructive sleep apnea is a chronic condition characterized by recurrent episodes of apneas or hypopneas during sleep leading to intermittent hypoxemia and arousals. The prevalence of the sleep disordered breathing is estimated that almost 50% of men and 24% of women suffer from moderate to severe form of the disorder. Snoring, collapse of upper airways and intermittent hypoxia are main causes of smoldering systemic inflammation in patients suffering from obstructive sleep apnea. The systematic inflammation is considered one of the key mechanisms leading to significant cardiovascular complications. Blood platelets, formerly not even recognized as cells, are currently gaining attention as crucial players in the immune continuum. Platelet surface is endowed with receptors characteristic for cells classically belonging to the immune system, which enables them to recognize pathogens, immune complexes, and interact in a homo- and heterotypic aggregates. Platelets participate in the process of transcellular production of bioactive lipids by delivering both specific enzymes and substrate molecules. Despite their lack of nucleus, platelets synthetize proteins in a stimuli-dependent manner. Atherosclerosis and consequent cardiovascular complications result from disruption in homeostasis of both of the platelet roles: blood coagulation and inflammatory processes modulation. Platelet parameters, routinely evaluated as a part of complete blood count test, were proposed as markers of cardiovascular comorbidity in patients with obstructive sleep apnea. Platelets were found to be excessively activated in this group of patients, especially in obese subjects. Persistent activation results in enhanced spontaneous aggregability and change in cytokine production. Platelet-lymphocyte ratio was suggested as an independent marker for cardiovascular disease in obstructive sleep apnea syndrome and continuous positive air pressure therapy was found to have an impact on platelet parameters and phenotype. In this literature review we summarize the current knowledge on the subject of platelets involvement in obstructive sleep apnea syndrome and consider the possible pathways in which they contribute to cardiovascular comorbidity.