Atrial fibrillation in obstructive sleep apnea

Prevalence of Obstructive Sleep Apnea Among Atrial Fibrillation Patients: A Cross-Sectional Study from Jordan

Background

Obstructive Sleep Apnea (OSA) is a common respiratory disorder that causes intermittent upper airway collapse during sleep and can lead to various acute cardiovascular complications. Atrial Fibrillation (AF) is the most common sustained cardiac arrhythmia and is associated with an increased risk of cardiovascular hospitalization and all-cause mortality. Our study aimed to investigate the prevalence of individuals with AF and those considered at high risk for OSA.

Methods

A cross-sectional study was conducted with a population comprising patients who had visited KAUH cardiology clinics between 2017-2019; subjects were categorized into AF patients and general cardiology patients. Patients were surveyed for OSA using the Berlin Questionnaire to assess the degree of OSA symptoms and to classify patients into high- or low-risk groups based on their responses.

Results

Of the 656 patients, 545 met our inclusion criteria, of whom 192 were diagnosed with AF. Comparable demographic characteristics were observed between the AF and non-AF groups, barring higher rates of obesity (p=0.001) and smoking (p=0.042) in the AF group. The prevalence of high-risk OSA was significantly higher in AF patients (68.2%) compared to non-AF patients (29.4%), with an adjusted odds ratio of 2.473 times (95% CI: 1.434 -4.266, p=0.001) greater for AF. The age, gender, and BMI categories did not differ significantly between the two groups. Binary logistic regression revealed significant associations between OSA and risk factors such as asthma (OR=4.408, 95% CI: 2.634-7.376, p=0.001).

Conclusion

These results serve to display a statistically significant increase in high-risk OSA in existing AF patients, irrespective of the presence of conventional OSA risk factors; this could imply a more immediate and direct relationship between both diseases and calls to include routine screening for OSA in patients diagnosed, newly or otherwise, with AF.

Midazolam versus Dexmedetomidine in Patients at Risk of Obstructive Sleep Apnea during Urology Procedures: A Randomized Controlled Trial

Benzodiazepines are the most commonly used sedatives for the reduction of patient anxiety. However, they have adverse intraoperative effects, especially in obstructive sleep apnea (OSA) patients. This study aimed to compare dexmedetomidine (DEX) and midazolam (MDZ) sedation considering intraoperative complications during transurethral resections of the bladder and prostate regarding the risk for OSA. This study was a blinded randomized clinical trial, which included 115 adult patients with a mean age of 65 undergoing urological procedures. Patients were divided into four groups regarding OSA risk (low to medium and high) and choice of either MDZ or DEX. The doses were titrated to reach a Ramsay sedation scale score of 4/5. The intraoperative complications were recorded. Incidence rates of desaturations (44% vs. 12.7%, p = 0.0001), snoring (76% vs. 49%, p = 0.0008), restlessness (26.7% vs. 1.8%, p = 0.0044), and coughing (42.1% vs. 14.5%, p = 0.0001) were higher in the MDZ group compared with DEX, independently of OSA risk. Having a high risk for OSA increased the incidence rates of desaturation (51.2% vs. 15.7%, p < 0.0001) and snoring (90% vs. 47.1%, p < 0.0001), regardless of the sedative choice. DEX produced fewer intraoperative complications over MDZ during sedation in both low to medium risk and high-risk OSA patients.

Intermittent Hypoxia and Atherosclerosis: From Molecular Mechanisms to the Therapeutic Treatment

Intermittent hypoxia (IH) has a dual nature. On the one hand, chronic IH (CIH) is an important pathologic feature of obstructive sleep apnea (OSA) syndrome (OSAS), and many studies have confirmed that OSA-related CIH (OSA-CIH) has atherogenic effects involving complex and interacting mechanisms. Limited preventive and treatment methods are currently available for this condition. On the other hand, non-OSA-related IH has beneficial or detrimental effects on the body, depending on the degree, duration, and cyclic cycle of hypoxia. It includes two main states: intermittent hypoxia in a simulated plateau environment and intermittent hypoxia in a normobaric environment. In this paper, we compare the two types of IH and summarizes the pathologic mechanisms and research advances in the treatment of OSA-CIH-induced atherosclerosis (AS), to provide evidence for the systematic prevention and treatment of OSAS-related AS.

Postoperative Atrial Fibrillation in Adults with Obstructive Sleep Apnea Undergoing Coronary Artery Bypass Grafting in the RICCADSA Cohort

Postoperative atrial fibrillation (POAF) occurs in 20−50% of patients with coronary artery disease (CAD) after coronary artery bypass grafting (CABG). Obstructive sleep apnea (OSA) is also common in adults with CAD, and may contribute to POAF as well to the reoccurrence of AF in patients at long-term. In the current secondary analysis of the Randomized Intervention with Continuous Positive Airway Pressure (CPAP) in Coronary Artery Disease and Obstructive Sleep Apnea (RICCADSA) trial (Trial Registry: ClinicalTrials.gov; No: NCT 00519597), we included 147 patients with CABG, who underwent a home sleep apnea testing, in average 73 ± 30 days after the surgical intervention. POAF was defined as a new-onset AF occurring within the 30 days following the CABG. POAF was observed among 48 (32.7%) patients, occurring within the first week among 45 of those cases. The distribution of the apnea-hypopnea-index (AHI) categories < 5.0 events/h (no-OSA); 5.0−14.9 events/h (mild OSA); 15.0−29.9 events/h (moderate OSA); and ≥30 events/h (severe OSA), was 4.2%, 14.6%, 35.4%, and 45.8%, in the POAF group, and 16.2%, 17.2%, 39.4%, and 27.3%, respectively, in the no-POAF group. In a multivariate logistic regression model, there was a significant risk increase for POAF across the AHI categories, with the highest odds ratio (OR) for severe OSA (OR 6.82, 95% confidence interval 1.31−35.50; p = 0.023) vs. no-OSA, independent of age, sex, and body-mass-index. In the entire cohort, 90% were on β-blockers according to the clinical routines, they all had sinus rhythm on the electrocardiogram at baseline before the study start, and 28 out of 40 patients with moderate to severe OSA (70%) were allocated to CPAP. During a median follow-up period of 67 months, two patients (none with POAF) were hospitalized due to AF. To conclude, severe OSA was significantly associated with POAF in patients with CAD undergoing CABG. However, none of those individuals had an AF-reoccurrence at long term, and whether CPAP should be considered as an add-on treatment to β-blockers in secondary prevention models for OSA patients presenting POAF after CABG requires further studies in larger cohorts.

Modifiable Risk Factors and Atrial Fibrillation: the Quest for a Personalized Approach

Background:Atrial fibrillation (AF) is the most common tachyarrhythmia, affecting up to 4% of the general population. Susceptibility to AF episodes can be explained by various risk factors (RF) that alter the substrate of the left atrium. Association between several RF and AF development and recurrence has been demonstrated in several studies. Areas of uncertainty: Treatment strategies depend on patients' characteristics and comorbidities. Medical literature and consensus documents recommend an integrated approach, but also identify evidence gaps in treating patients with severe comorbidities. Data sources: Literature search was performed using PubMed electronic database. We used the following terms as key words: atrial fibrillation, risk factors, comorbidities, primary prevention, secondary prevention. Results: Active intervention helps control the burden of AF and increase the chances of a positive outcome on the long term. Aggressive control and individualized treatment of most prevalent modifiable risk factors can reduce the risk of atrial fibrillation. Optimization of treatment strategy should be performed periodically, since RF and comorbidities are dynamic and often evolve. Conclusion:Personalized strategies should be applied to each patient after careful assessment of individual risk. A personalized approach is indicated to both reduce the burden of AF and improve symptoms, quality of life and survival. Close attention to details is required to avoid disease and therapy related complications in the presence of comorbidities.

The Goals of Treating Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) syndrome is a destructive and insidious entity mostly underdiagnosed and undertreated. It affects not only individuals but the society as a whole. The costs to the populations can be measured not only in morbidity and mortality but also in the financial wellbeing of a society. Financial burden of this disease is staggering. The social fabric of society is also greatly impacted. Physiologic effects of OSA are far reaching. It has been shown that early intervention with treatment of OSA can often prevent and/or reverse many of the negative outcomes associated with this condition.

A Guide to Management of Sleepiness in ESKD

Daytime sleepiness, also known as hypersomnolence, is common among patients receiving maintenance dialysis and following successful kidney transplantation. Sleepiness may be secondary to medical comorbid conditions, medication side effect, insufficient sleep syndrome, and sleep-disordered breathing or the result of a primary central disorder of hypersomnolence, such as narcolepsy. Unrecognized and untreated sleep disorders are associated with substantial morbidity and mortality among patients with end-stage kidney disease. Effective management of hypersomnolence can improve quality of life in patients with kidney disease. This review focuses on the principal causes of sleepiness in patients with end-stage kidney disease. Awareness of these disorders by treating nephrologists is crucial. This review provides a systematic approach to guide providers through the recognition, early diagnosis, and treatment of hypersomnolence, which is commonly encountered in this patient population. Areas of future research are also suggested.

Arrhythmogenic mechanisms of obstructive sleep apnea in heart failure patients

Heart failure (HF) affects 23 million people worldwide and results in 300000 annual deaths. It is associated with many comorbidities, such as obstructive sleep apnea (OSA), and risk factors for both conditions overlap. Eleven percent of HF patients have OSA and 7.7% of OSA patients have left ventricular ejection fraction <50% with arrhythmias being a significant comorbidity in HF and OSA patients. Forty percent of HF patients develop atrial fibrillation (AF) and 30%-50% of deaths from cardiac causes in HF patients are from sudden cardiac death. OSA is prevalent in 32%-49% of patients with AF and there is a dose-dependent relationship between OSA severity and resistance to anti-arrhythmic therapies. HF and OSA lead to various downstream arrhythmogenic mechanisms, including metabolic derangement, remodeling, inflammation, and autonomic imbalance. (1) Metabolic derangement and production of reactive oxidative species increase late Na+ currents, decrease outward K+ currents and downregulate connexin-43 and cell-cell coupling. (2) remodeling also features downregulated K+ currents in addition to decreased Na+/K+ ATPase currents, altered Ca2+ homeostasis, and increased density of If current. (3) Chronic inflammation leads to downregulation of both Nav1.5 channels and K+ channels, altered Ca2+ homeostasis and reduced cellular coupling from alterations of connexin expression. (4) Autonomic imbalance causes arrhythmias by evoking triggered activity through increased Ca2+ transients and reduction of excitation wavefront wavelength. Thus, consideration of these multiple pathophysiological pathways (1-4) will enable the development of novel therapeutic strategies that can be targeted against arrhythmias in the context of complex disease, such as the comorbidities of HF and OSA.

The relationship between the nutritional status and sleep quality of patients with atrial fibrillation

Objectives:

To evaluate the relationship between the nutritional status and sleep quality in patients diagnosed with atrial fibrillation as a cross-sectional correlational research.

Methods:

This cross-sectional correlational research was carried out with 108 patients between December 2017 and March 2018 who were admitted to the cardiology services of 2 different universities, diagnosed with atrial fibrillation and agreed to participate. Data collection was performed using internationally valid scales in order to evaluate the relationship between the nutritional status and sleep quality of patients diagnosed with atrial fibrillation.

Results:

Of the patients, 47.2% were men and 52.8% were women. Most of them (81.5%) were over the age of 60 years. The mean age was 68.99±14.02. Of the patients, 13% were malnourished, 57.4% were at risk of malnutrition, and 29.6% had a normal nutritional status. This study determined that their sleep quality worsened and their daytime sleepiness increased as their risk of malnutrition increased (p=0.000).

Conclusion:

The patients’ sleep quality worsened and their daytime sleepiness increased as the risk of malnutrition increased.

Obstructive Sleep Apnea Screening in Patients With Atrial Fibrillation: Missed Opportunities for Early Diagnosis

BACKGROUND

"There is a high prevalence of obstructive sleep apnea (OSA) among patients with atrial fibrillation (AF). There is also strong evidence that proper OSA management can reduce AF recurrence." Polysomnography is the gold standard for OSA diagnosis, but screening tests, such as STOP-BANG, have been successful in identifying patients at risk for OSA. Our study assesses screening rates for OSA in patients with persistent AF, and willingness of patients at increased risk for OSA towards further diagnostic evaluation.

METHODS

A total of 254 persistent AF patients were surveyed regarding prior screening for OSA, and if previously unscreened, assessed with STOP-BANG. Prior cardioversions and willingness to undergo further workup was also recorded. Patients at risk for OSA were given educational brochures. Subjects with diagnosis of OSA were asked about their compliance with positive airway pressure therapy.

RESULTS

Sixty-six percent of AF patients were never screened for OSA; 75% unscreened participants (95% CI: 68-81%) were at high risk for OSA. Patients with previous hospitalizations or electrical cardioversions were more frequently screened for OSA (P = 0.02, P = 0.03, respectively). Forty-three percent of high-risk individuals had a BMI < 30. Among patients at risk for OSA (score ≥ 3), the majority (n = 99, 79%) were interested in follow-up with a sleep study (n = 93, 74%).

CONCLUSIONS

Although there is a strong OSA-associated risk for AF, which is amenable to intervention, most patients with persistent AF are not assessed for OSA. Simple to use screening questionnaires are sensitive and can reliably identify patients at high risk for OSA, reserving costlier and somewhat inconvenient nocturnal polysomnography to only those at risk. We hope our study will help to push the AF and OSA connection into the spotlight in the primary care of patients with AF.

Connexins and Atrial Fibrillation in Obstructive Sleep Apnea

PURPOSE OF THE REVIEW

To summarize the potential interactions between obstructive sleep apnea (OSA), atrial fibrillation (AF), and connexins.

RECENT FINDINGS

OSA is highly prevalent in patients with cardiovascular disease, and is associated with increased risk for end-organ substantial morbidities linked to autonomic nervous system imbalance, increased oxidative stress and inflammation, ultimately leading to reduced life expectancy. Epidemiological studies indicate that OSA is associated with increased incidence and progression of coronary heart disease, heart failure, stroke, as well as arrhythmias, particularly AF. Conversely, AF is very common among subjects referred for suspected OSA, and the prevalence of AF increases with OSA severity. The interrelationships between AF and OSA along with the well-known epidemiological links between these two conditions and obesity may reflect shared pathophysiological pathways, which may depend on the intercellular diffusion of signaling molecules into either the extracellular space or require cell-to-cell contact. Connexin signaling is accomplished via direct exchanges of cytosolic molecules between adjacent cells at gap membrane junctions for cell-to-cell coupling. The role of connexins in AF is now quite well established, but the impact of OSA on cardiac connexins has only recently begun to be investigated. Understanding the biology and regulatory mechanisms of connexins in OSA at the transcriptional, translational, and post-translational levels will undoubtedly require major efforts to decipher the breadth and complexity of connexin functions in OSA-induced AF.

SUMMARY

The risk of end-organ morbidities has initiated the search for circulating mechanistic biomarker signatures and the implementation of biomarker-based algorithms for precision-based diagnosis and risk assessment. Here we summarize recent findings in OSA as they relate to AF risk, and also review potential mechanisms linking OSA, AF and connexins.

Prevalence of atrial fibrillation with insertable cardiac monitors in cryptogenic stroke: A single-center experience

BACKGROUND

The use of insertable cardiac monitors (ICM) has increased the rate of detection of atrial fibrillation (AF) among cryptogenic stroke (CS) patients. We describe a single-center experience for AF detection among CS patients receiving ICMs upon discharge after the index stroke event and attempt to identify predictors for AF detection.

METHODS

From April 2014 to October 2017, patients receiving ICMs for CS who underwent >60 days of monitoring were reviewed. Chronic underlying medical illnesses, presence of left atrial enlargement (LAE) on echocardiography, and PR interval on admission electrocardiogram were assessed as predictors of AF detection.

RESULTS

A total of 234 patients (median age 72 [61, 78] years, 45% women) met inclusion criteria and were followed for a median of 536 [282, 848] days. Among studied patients, 68 patients (29%) were found to have AF at a median of 94.5 [16, 239] days from ICM placement. CS patients with AF were significantly older (p < 0.001), and there was a significantly higher proportion of women (p = 0.003) when compared to CS patients without AF. Neither presence of LAE nor prolonged PR interval was predictive of AF detection.

CONCLUSION

Almost one-third of CS patients monitored with an ICM were found to have previously undiagnosed AF. CS patients found to have AF were older and more commonly women. Prospective studies are needed to better identify predictors for early AF among the broader population of all CS patients.

Impact of obstructive sleep apnea on neurological recovery after ischemic stroke: A prospective study

OBJECTIVES

The presence of obstructive sleep apnea (OSA) has been found to adversely affect the neurological recovery after acute ischemic stroke (AIS) in previous observational studies. However, in most of these studies, diagnosis of OSA was based on oximetry data alone, raising concern in the accuracy of diagnosis as well as estimation of severity. Purpose of our study was to determine the prevalence and severity of OSA (based on polysomnography and American Association of Sleep Medicine [AASM] criteria) in patients with AIS and to compare the post-stroke neurological and functional outcome, in those with and without OSA.

MATERIALS AND METHODS

A prospective single-centre study was conducted over a period of eighteen months from January 2013. The demographic and clinical data were collected, and the etiology of stroke was classified according to TOAST classification. Subsequently, all selected patients (N=99) underwent premorbid sleep status assessment by Epworth Sleepiness Scale followed by polysomnography using Resmed ApneaLink polysomnograph. Data were analyzed to find out the prevalence and severity of OSA as well as its impact on neurological recovery as assessed by National Institutes of Health Stroke Scale (NIHSS) and modified Rankin scale (mRS) at different time points, starting from admission.

RESULTS

There was a high prevalence of OSA (~60%) with a quarter of them having severe OSA. The OSA group had a significantly higher mean NIHSS score at discharge (P=.002) and significantly higher mRS score (irrespective of severity of OSA) at all points of evaluation.

CONCLUSION

Ischemic stroke patients with OSA tend to have poor neurological and functional recovery, across all segments of stroke and OSA severity.

OSA and Cardiac Arrhythmogenesis: Mechanistic Insights

A surge of data has reproducibly identified strong associations of OSA with cardiac arrhythmias. As an extension of epidemiologic and clinic-based findings, experimental investigations have made strides in advancing our understanding of the putative OSA and cardiac arrhythmogenesis mechanistic underpinnings. Although most studies have focused on the links between OSA and atrial fibrillation (AF), relationships with ventricular arrhythmias have also been characterized. Key findings implicate OSA-related autonomic nervous system fluctuations typified by enhanced parasympathetic activation during respiratory events and sympathetic surges subsequent to respiratory events, which contribute to augmented arrhythmic propensity. Other more immediate pathophysiologic influences of OSA-enhancing arrhythmogenesis include intermittent hypoxia, intrathoracic pressure swings leading to atrial stretch, and hypercapnia. Intermediate pathways by which OSA may trigger arrhythmia include increased systemic inflammation, oxidative stress, enhanced prothrombotic state, and vascular dysfunction. Long-term OSA-associated sequelae such as hypertension, atrial enlargement and fibrosis, ventricular hypertrophy, and coronary artery disease also predispose to cardiac arrhythmia. These factors can lead to a reduction in atrial effective refractory period, triggered and abnormal automaticity, and promote slowed and heterogeneous conduction; all of these mechanisms increase the persistence of reentrant arrhythmias and prolong the QT interval. Cardiac electrical and structural remodeling observed in OSA animal models can progress the arrhythmogenic substrate to further enhance arrhythmia generation. Future investigations clarifying the contribution of specific OSA-related mechanistic pathways to arrhythmia generation may allow targeted preventative therapies to mitigate OSA-induced arrhythmogenicity. Furthermore, interventional studies are needed to clarify the impact of OSA pathophysiology reversal on cardiac arrhythmogenesis and related adverse outcomes.

Obstructive Sleep Apnoea and Atrial Fibrillation

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia and is associated with significant morbidity and mortality. Obstructive sleep apnoea (OSA) is common among patients with AF. Growing evidence suggests that OSA is associated with the initiation and maintenance of AF. This association is independent of obesity, body mass index and hypertension. OSA not only promotes initiation of AF but also has a significant negative impact on the treatment of AF. Patients with untreated OSA have a higher AF recurrence rate with drug therapy, electrical cardioversion and catheter ablation. Treatment with continuous positive airway pressure (CPAP) has been shown to improve AF control in patients with OSA. In this article, we will review and discuss the pathophysiological mechanisms of OSA that may predispose OSA patients to AF as well as the standard and emerging therapies for patients with both OSA and AF.

Diabetes, sleep apnea, obesity and cardiovascular disease: Why not address them together?

Obesity, sleep apnea, diabetes and cardiovascular diseases are some of the most common diseases encountered by the worldwide population, with high social and economic burdens. Significant emphasis has been placed on obtaining blood pressure, body mass index, and placing importance on screening for signs and symptoms pointing towards cardiovascular disease. Symptoms related to sleep, or screening for sleep apnea has been overlooked by cardiac, diabetic, pulmonary and general medicine clinics despite recommendations for screening by several societies. In recent years, there is mounting data where obesity and obstructive sleep apnea sit at the epicenter and its control can lead to improvement and prevention of diabetes and cardiovascular complications. This editorial raises questions as to why obstructive sleep apnea screening should be included as yet another vital sign during patient initial inpatient or outpatient visit.

Severity of obstructive sleep apnea influences the effect of genotype on response to anti-arrhythmic drug therapy for atrial fibrillation

STUDY OBJECTIVES

To examine the impact of genotype on the relationship between obstructive sleep apnea (OSA) and anti-arrhythmic drug (AAD) efficacy in atrial fibrillation (AF).

DESIGN

Registry based.

SETTING

Clinic-based.

PARTICIPANTS

Eighty-four individuals from Vanderbilt AF registry who had polysomnography, genotyping, and serial comprehensive evaluations of AF status.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Response to AADs was defined as a decrease in AF burden score by ≥ 75% or the combination of sinus rhythm on follow-up EKGs, stable AAD therapy for at least 6 months, objective AF burden below an established threshold, and the absence of non-pharmacologic therapies. Participants were genotyped for common AF susceptibility alleles at chromosomes 4q25 (near PITX2), 16q22 (in ZFHX3), and 1q21 (in KCNN3), and common SNPs in the β1-adrenergic receptor (ARDB1). Wild-type status for rs10033464 at 4q25 was associated with increased success of AAD therapy in patients with no or mild OSA (odds ratio: 10.0, 95% confidence interval: 1.03 to 97.5; p < 0.05), but did not influence response to AAD therapy in those with moderate-severe OSA. A similar trend was observed for rs1801252 on ARDB1.

CONCLUSION

In this hypothesis-generating pilot study of predominantly Caucasian men, the effect on AF response to AAD therapy of rs10033464 at 4q25 varied based on OSA status. The impact of genotype on AAD efficacy may be greatest in mild OSA and attenuated in more severe disease.

Predictors of long-term maintenance of normal sinus rhythm after successful electrical cardioversion

Electrical cardioversion (EC) for atrial fibrillation (AF) is a common procedure performed in an attempt to restore normal sinus rhythm (NSR). Many factors predict long-term maintenance of NSR and the risk of AF recurrence. The duration of AF, cardiac size and function, rheumatic heart disease, significant mitral valve disease, left atrial enlargement, and older age are among the most common recognized factors. A number of interventions can potentially decrease the AF recurrence rate. Identifying and treating reversible causes and the use of antiarrhythmic medications in certain situations can help decrease the risk of AF recurrence. The role of the newer anticoagulants is expanding, and wider application is expected in the near future. We hope that this summary will serve as a guide to physicians and healthcare providers to address the question of who should undergo cardioversion, as there are patients who are most likely to benefit from this procedure and others that will revert back into AF within a short period. To identify who would benefit most from EC and have a reasonable chance of long-term maintenance of NSR, a thorough evaluation of each individual patient should be performed to tailor the best therapy to each individual.

[Medicinal treatment of atrial fibrillation in special situations]

The treatment of atrial fibrillation has to take into account the underlying cardiac and extracardiac diseases. A successful treatment of the underlying disease will only be sufficient treatment of atrial fibrillation in very rare situations. Therefore, this review focuses on the consequences of underlying heart disease, the hemodynamics and concomitant clinical situations on the treatment of atrial fibrillation.

The effect of sleep disordered breathing on the outcome of stroke and transient ischemic attack: a systematic review

STUDY OBJECTIVES

The primary objective was to systematically review the literature on how sleep disordered breathing (SDB) affects recurrence and death among stroke or transient ischemic attack (TIA) patients. A secondary objective was to evaluate how treatment of SDB with continuous positive airway pressure (CPAP) affects the risk of recurrence and death in these patients.

METHODS

Adults (18+) with a stroke or TIA diagnosis were eligible for inclusion. Case groups consisted of patients with a sleep disorder. The outcomes of interest were all-cause mortality, recurrent vascular events, and case fatality.

RESULTS

Ten articles covering 1,203 stroke and TIA patients were included in the review. The results generally support a dose-response relationship between severity of SDB and risk of recurrent events and all-cause mortality in stroke and TIA patients. Three small-scale articles with substantial risk of bias evaluated the effects of CPAP therapy, and the results are inconclusive. Data on case fatality is too sparse to be conclusive.

CONCLUSIONS

Existing studies provide sufficient data to establish obstructive SDB as a negative predictor of all-cause mortality and recurrent vascular events following stroke or TIA. The ability of CPAP treatment to lower the risk of serious adverse outcomes after stroke remains controversial because of substantial risk of bias identified in most of the eligible studies addressing this relation. Additional studies are needed.