Sleep apnea and cardiovascular disease: a bidirectional relationship

Sleep and Cardiovascular Health

Sleep is recognized as a foundational pillar of health, essential for maintaining nearly all vital processes, and a crucial component of cardiovascular function. In recent years, there has been a paradigm shift to conceptualize sleep health as a combination of multiple domains, including duration, timing, quality, variability/regularity, habits/behaviors, and disordered sleep. This review provides a comprehensive overview of the current evidence linking the multifaceted elements that contribute to healthy sleep with cardiovascular and blood pressure-related outcomes. The reviewed literature indicates a strong relationship between sleep and cardiovascular health. However, the specific pathophysiological mechanisms that bridge the various dimensions of sleep with cardiovascular outcomes remain elusive. Given the global burden of cardiovascular disease, understanding the interplay between sleep and cardiovascular health has important implications for both individual and population health. Sustained efforts to move beyond a focus on discrete domains of sleep are essential to fully understand this complex and potentially bidirectional relationship. Promoting healthy sleep patterns and optimizing the management and treatment of sleep disorders are key steps toward developing more comprehensive strategies for reducing cardiovascular risk. Integrating sleep health into routine clinical care is identified as a critical opportunity to enhance cardiovascular disease prevention and management, particularly among vulnerable and high-risk populations.

LV Structure and Function in HFrEF With and Without Peak-Flow-Triggered Adaptive Servo-Ventilation-Treated Sleep-Disordered Breathing

BACKGROUND

Sleep-disordered breathing (SDB), comprising obstructive sleep apnea (OSA) and central sleep apnea (CSA), could promote left ventricular (LV) remodeling and systolic dysfunction.

OBJECTIVES

The authors tested the hypothesis, in the ADVENT-HF (Adaptive Servo-ventilation for Sleep-disordered Breathing in Patients with Heart Failure with Reduced Ejection Fraction) trial, that SDB is associated with reversible impairment of LV structure and function.

METHODS

Participants underwent echocardiography (ejection fraction ≤45%) and polysomnography. They were classified as no-SDB (apnea-hypopnea index [AHI] <15/h); OSA (AHI ≥15/h with ≥50% of events obstructive), or CSA (AHI ≥15 with >50% of events central). Those with SDB were randomized to a control group or to peak-flow-triggered adaptive servo-ventilation (ASVPF) to treat SDB and, in them, echocardiography was repeated 6 months later.

RESULTS

Subjects with OSA (n = 543) had similar LV structure and function to those without SDB (n = 56). Subjects with CSA (n = 201) had greater LV mass index and lower LV ejection fraction than the other groups. LV volumes were higher in the CSA than in the OSA group (P < 0.05 for all). ASVPF abolished SDB, but had no significant effect, whether evaluated by allocation or adherence, 6 months post-randomization on LV structure or function for the entire cohort (n = 549), or either subgroup.

CONCLUSIONS

Among patients with heart failure with reduced ejection fraction, those with OSA had similar LV structure and function to those without SDB. Patients with CSA had greater LV remodeling and systolic dysfunction than those with OSA or without SDB. Six months of SDB suppression of OSA and CSA by ASVPF had no impact on LV structure or function. (Adaptive Servo-ventilation for Sleep-disordered Breathing in Patients with Heart Failure with Reduced Ejection Fraction [ADVENT-HF]).

Increased Myocardial MARK4 Expression in Patients with Heart Failure and Sleep-Disordered Breathing

Cardiovascular diseases are the leading cause of morbidity and mortality worldwide, underscoring the urgent need for novel therapeutic targets and strategies. The kinase MARK4 (MAP (microtubule-associated proteins)/microtubule affinity-regulating kinase 4) regulates microtubule-associated proteins pivotal for cell polarity, protein stability, and intracellular signaling. Animal models of heart failure revealed elevated MARK4 levels, which correlated with impaired cardiac contractility. However, the involvement of MARK4 and its potential as a molecular drug target has not yet been explored in the myocardium of cardiovascular patients. We investigated the MARK4 mRNA expression in human myocardial biopsies of 152 high-risk cardiovascular patients undergoing cardiac surgery. Comprehensive echocardiography as well as testing for sleep-disordered breathing (SDB), a critical comorbidity in heart failure, were assessed preoperatively. We observed a substantial upregulation of myocardial MARK4 expression in patients with impaired cardiac contractility, resulting in an inverse correlation with the left ventricular ejection fraction. Myocardial MARK4 expression also correlated with echocardiographic E/e', a central parameter of diastolic dysfunction. Mechanistically, our analyses revealed that MARK4 expression increases in SDB and under hypoxic conditions, as evidenced by significant correlations between myocardial MARK4 expression and factors like mean oxygen saturation, time with oxygen saturation below 90%, and the oxygen desaturation index. Multivariable regression analysis revealed that both left ventricular ejection fraction and mean oxygen saturation were independently associated with dysregulated MARK4 levels, even when controlling for important clinical covariables as potential confounders. Taken together, our findings demonstrate that MARK4 expression is highly increased in the myocardium of cardiovascular high-risk patients, suggesting it is a potential molecular target against cardiovascular diseases.

Sleep stage, sleep fragmentation and heart rate variability during the initial 3-h sleep period in patients with obstructive sleep apnea syndrome

To investigate differences in polysomnography (PSG) parameters and heart rate variability (HRV) during the initial 3-h sleep period in patients with mild, moderate, and severe obstructive sleep apnea syndrome (OSA). According to the apnea-hypopnea index, patients were divided into 3 groups: mild, moderate, and severe (n = 23, 59, and 94, respectively). PSG was performed, and HRV (frequency domain analysis), sleep stage (S1, S2, S3, REM, and waking), and sleep fragmentation index (SFI) were measured during the initial 3-h sleep periods. The total S1 time was significantly longer in the severe group than in the mild and moderate groups (p < 0.001). The severe group had significantly shorter total S2 and S3 times than the mild (p = 0.014, p < 0.001) and moderate (p = 0.034, p = 0.029) groups did. The SFI was significantly greater in the severe group than in the mild and moderate groups (p < 0.001, p = 0.008). The high-frequency component (HF) of the HRV showed no significant differences except that it was significantly smaller during S3 in the moderate group than in the mild group (p = 0.026). Compared with those with mild/moderate status, patients with severe OSA have shallower sleep and a higher SFI, suggesting poorer sleep quality. Although HF during S3 was significantly smaller in the moderate group, it did not significantly differ between the mild and severe groups, suggesting that the parasympathetic nervous system might compensate for humoral and hypoxemic abnormalities in patients with severe OSA.

Association between obstructive sleep apnea and migraine: A United States population-based cohort study

OBJECTIVE

To determine the association between obstructive sleep apnea (OSA) and the incidence of migraine using a large population-based dataset, as well as to identify the at-risk target groups.

BACKGROUND

Epidemiological and biochemical studies have provided evidence for the close connection between sleep disorders and migraine. Understanding the connections between OSA and migraine, as well as their shared risk factors, may provide new perspectives on the pathophysiology of both OSA and migraine and novel approaches to managing and treating these conditions.

METHODS

This retrospective cohort study used data from the TriNetX network from 2010 to 2021. We compared 196,864 adult participants with OSA to a group of 196,864 participants who had never been diagnosed with OSA (1:1 propensity score-matching for age, sex, race, comorbidities, and body mass index [BMI] categories) in relation to the risk of incident migraine. We performed subgroup analyses based on age (18-39, 40-59, ≥60 years), sex (female, male), race (White, Black or African American, Asian), BMI categories (<18.5, 18.5-24.9, 25-29.9, ≥30 kg/m2), and the presence of hypoxemia (yes, no). Sensitivity analyses were performed to validate our findings.

RESULTS

During the follow-up period, 12,613 (6.4%) and 6356 participants (3.2%) developed migraine in the OSA and non-OSA cohorts, respectively. Patients with OSA were found to have a 1.85-fold risk (hazard ratio [HR] 1.85; 95% confidence interval [CI] 1.79-1.90) of incident migraine when compared to those without OSA, after accounting for age, sex, race, and baseline comorbidities. The results were consistent in sensitivity analyses (test-negative design: HR 1.39, 95% CI 1.28-1.49) and also cross-validated in a different dataset from TriNetX (Global Collaborative Research Network: HR 1.88, 95% CI 1.82-1.93). The results of subgroup analysis by sex, age, race, BMI categories, and the presence of hypoxemia were generally consistent.

CONCLUSION

We found OSA to be associated with an elevated risk of developing migraine using a large United States nationwide database, and the association was generalizable across sex, age, race, and BMI categories. Our results suggest that awareness of migraine should be increased among patients with OSA. The findings also encourage further research to clarify the role of obesity and overweight in the relationship between OSA and migraine, as well as the potential benefits of body weight control for those with these two comorbid conditions.

Nomogram for predicting olfactory disorder in obstructive sleep apnea: A retrospective study based on a multicenter database

OBJECTIVE

Obstructive sleep apnea (OSA) increases the risk of olfactory disorder (OD), which may serve as an early warning of adverse health consequences. In this study, we aimed to develop and validate a nomogram for early detection of OD in patients with OSA.

METHODS

We retrospectively analyzed 125 patients with OSA at Beijing Anzhen Hospital for the development and internal validation of the nomogram. For external validation, 30 patients with OSA were recruited from the Air Force Medical Center. The included participants completed polysomnography (PSG) and the Sniffin' Sticks test. Patients with OSA were divided into two groups: OSA with OD and OSA without OD.

RESULTS

The nomogram included age, sex, and time spent with oxygen saturation below 90%. The area under the receiver operating characteristic curve of the nomogram was 0.814 (95% confidence interval [CI]: 0.673-0.955) for the internal validation group, and 0.778 (95% CI: 0.601-0.955) for the external validation group. The nomogram exhibited excellent discrimination and calibration, showing substantial benefits in clinical applications.

CONCLUSION

The present nomogram developed based on clinical characteristics and PSG features can serve as a convenient tool for clinicians to detect OD in OSA, aiding in patient stratification and personalized treatment.

Correlates of sleep-disordered breathing and Cheyne-Stokes respiration in patients with atrial fibrillation who have undergone pulmonary vein isolation

Sleep disordered breathing (SDB) is a common comorbidity in patients with atrial fibrillation (AF). Patients undergoing pulmonary vein isolation (PVI) for AF have a high prevalence of SDB. In previous studies, some patients with AF had Cheyne-Stokes respiration (CSR). The aim of the present study was to assess the prevalence of SDB and the correlates of SDB severity and CSR in AF patients who have undergone PVI. The study was conducted using a single-center observational design. All participants underwent a home sleep apnea test (ApneaLink Air, ResMed, Australia), which could determine the severity of SDB as assessed by the apnea-hypopnea index (AHI) and the percentage of CSR (%CSR) pattern. 139 AF patients who underwent PVI were included in the study. Overall, 38 (27.3%) patients had no SDB (AHI < 5), 53 (38.1%) had mild SDB (5 ≤ AHI < 15), 33 (23.7%) had moderate SDB (15 ≤ AHI < 30), and 15 (10.8%) had severe SDB (AHI ≥ 30). Correlates of the increased AHI included male sex (β = 0.23, p = 0.004), age (β = 0.19, p = 0.020), high body mass index (β = 0.31, p < 0.001), and β blockers usage (β = 0.18, p = 0.024). Conversely, correlates with the %CSR rate included male sex (β = 0.18, p = 0.020), age (β = 0.19, p = 0.015), non-paroxysmal AF (β = 0.22, p = 0.008), and high glycohemoglobin A1c (β = 0.36, p < 0.001) and N-terminal pro-brain natriuretic peptide (β = 0.24, p = 0.005) levels. SDB is prevalent in patients with AF who have undergone PVI; predisposing factors for SDB include male sex, older age, and obesity. CSR occurs in patients with AF who have undergone PVI; predisposing factors for CSR include male sex, older age, high left ventricular filling pressure, and abnormal blood glucose level.

The chronobiology of human heart failure: clinical implications and therapeutic opportunities

Circadian variation in cardiovascular and metabolic dynamics arises from interactions between intrinsic rhythms and extrinsic cues. By anticipating and accommodating adaptation to awakening and activity, their synthesis maintains homeostasis and maximizes efficiency, flexibility, and resilience. The dyssynchrony of cardiovascular load and energetic capacity arising from attenuation or loss of such rhythms is strongly associated with incident heart failure (HF). Once established, molecular, neurohormonal, and metabolic rhythms are frequently misaligned with each other and with extrinsic cycles, contributing to HF progression and adverse outcomes. Realignment of biological rhythms via lifestyle interventions, chronotherapy, and time-tailored autonomic modulation represents an appealing potential strategy for improving HF-related morbidity and mortality.

Tofogliflozin reduces sleep apnea severity in patients with type 2 diabetes mellitus and heart failure: a prospective study

Sleep apnea (SA) is prevalent among patients with heart failure (HF) and contributes to a poor prognosis. Sodium-glucose cotransporter 2 (SGLT2) inhibitors have demonstrated efficacy in reducing the risk of serious clinical events in patients with HF. Additionally, SGLT2 inhibitors may reduce the risk of incident SA and mitigate its severity in patients with cardiovascular disease and T2DM. We aimed to investigate whether the SGLT2 inhibitor tofogliflozin reduced the severity of SA, as assessed using the apnea-hypopnea index (AHI), in patients with HF and T2DM and whether a decrease in AHI correlates with changes in body composition and cardiorenal function parameters. This is a single-arm, prospective pathophysiologic study involving patients with HF, T2DM, and SA, defined as having an AHI of 15 events/h and more. SA was assessed using polysomnography. Changes in AHI before and 6 months after starting oral administration of tofogliflozin (20 mg) were assessed. Additionally, body composition and cardiorenal functions were assessed before and 6 months after tofogliflozin administration. Ten patients with HF, T2DM, and SA were finally enrolled (60% men, 66.9 ± 13.4 years). Tofogliflozin reduced AHI from 43.2 [30.2] to 35.3 [13.1] events/h (p = 0.024) at 6 months. Hemoglobin A1c, body weight, and body water content decreased significantly. However, no significant changes were observed in the cardiorenal function parameters. A linear relationship was observed between the changes in body water content and AHI (r = 0.642, p = 0.045). Tofogliflozin reduced AHI, possibly associated with a reduction in body water content.

Obstructive sleep apnea -related hypertension: a review of the literature and clinical management strategy

Obstructive Sleep Apnea (OSA) and hypertension have a high rate of co-occurrence, with OSA being a causative factor for hypertension. Sympathetic activity due to intermittent hypoxia and/or fragmented sleep is the most important mechanisms triggering the elevation in blood pressure in OSA. OSA-related hypertension is characterized by resistant hypertension, nocturnal hypertension, abnormal blood pressure variability, and vascular remodeling. In particular, the prevalence of OSA is high in patients with resistant hypertension, and the mechanism proposed includes vascular remodeling due to the exacerbation of arterial stiffness by OSA. Continuous positive airway pressure therapy is effective at lowering blood pressure, however, the magnitude of the decrease in blood pressure is relatively modest, therefore, patients often need to also take antihypertensive medications to achieve optimal blood pressure control. Antihypertensive medications targeting sympathetic pathways or the renin-angiotensin-aldosterone system have theoretical potential in OSA-related hypertension, Therefore, beta-blockers and renin-angiotensin system inhibitors may be effective in the management of OSA-related hypertension, but current evidence is limited. The characteristics of OSA-related hypertension, such as nocturnal hypertension and obesity-related hypertension, suggests potential for angiotensin receptor-neprilysin inhibitor (ARNI), sodium-glucose cotransporter 2 inhibitors (SGLT2i) and glucose-dependent insulinotropic polypeptide receptor/ glucagon-like peptide-1 receptor agonist (GIP/GLP-1 RA). Recently, OSA has been considered to be caused not only by upper airway anatomy but also by several non-anatomic mechanisms, such as responsiveness of the upper airway response, ventilatory control instability, and reduced sleep arousal threshold. Elucidating the phenotypic mechanisms of OSA may potentially advance more personalized hypertension treatment strategies in the future. Clinical characteristics and management strategy of OSA-related hypertension. OSA obstructive sleep apnea, BP blood pressure, ABPM ambulatory blood pressure monitoring, CPAP continuous positive airway pressure, LVH left ventricular hypertrophy, ARB: angiotensin II receptor blocker, SGLT2i Sodium-glucose cotransporter 2 inhibitors, ARNI angiotensin receptor-neprilysin inhibitor, CCB calcium channel blocker, GIP/GLP-1 RA glucose-dependent insulinotropic polypeptide receptor and glucagon-like peptide-1 receptor agonist.

One Year Follow-Up Assessment of Impact of Rigorous Diet Regimen and Adequate C-PAP Therapy on Obese Patients with Obstructive Sleep Apnea Syndrome: A Retrospective Study

Background/Objectives: This study evaluated the impact of continuous positive airway pressure (C-PAP) therapy combined with a rigorous diet regimen on obese patients with obstructive sleep apnea syndrome (OSAS). Methods: Sixty obese patients (BMI ≥ 30) diagnosed with severe OSAS were recruited in order to establish the evaluation of CPAP therapy with different extents of adherence to a rigorous diet regimen. After one year, significant improvements were observed. Results: BMI reduced by 12.32%, apnea-hypopnea index (AHI) by 22.04%, oxygen desaturation index (ODI) by 15.87%, total sleep time with oxygen saturation below 90% (TST90%) by 25.2%, and Epworth Sleepiness Scale (ESS) scores by 21.74%. Patients were, then, divided into three groups, based on adherence to the restricted diet, as well as to the correct use of the nocturnal C-PAP, showing different reductions in BMI, AHI, ODI, TST90%, and ESS, according to their adherence, based on the sum of % reduction in BMI + AHI into three groups. Conclusions: These findings underscore the effectiveness of combining C-PAP therapy with a strict diet in improving OSAS symptoms and overall health in obese patients. Future studies with larger cohorts and longer follow-up periods are needed to confirm these results and explore the long-term benefits of this integrated approach.

Predicting heart failure symptoms from the apnoea-hypopnoea index determined by full- night polysomnography

AIMS

Sleep-disordered breathing (SDB) is closely related to cardiovascular diseases. The higher the apnoea-hypopnoea index (AHI), the higher the prevalence of cardiovascular diseases. Despite these findings suggesting a close link between SDB and heart failure, the relationship between the severity of SDB and the onset of heart failure symptoms in individuals without apparent heart failure symptoms (Heart Failure Stage A + B) remains poorly understood.

METHODS AND RESULTS

Between December 2010 and June 2017, we conducted full-night polysomnography (PSG) at the Nippon Medical School Chiba Hokusoh Hospital, extracting patients who were at risk of heart failure (Stage A or B in the Heart Failure Guidelines). Using a median cut-off of AHI ≥ 41.6 events/hour, we divided the patients into two groups and examined the composite endpoint of all-cause mortality plus hospitalization due to heart failure as the primary endpoint. We included 230 patients (mean age 63.0 ± 12.5 years, 78.3% males) meeting the selection criteria. When comparing the two groups, those with AHI < 41.6 events/hour (L group, n = 115) and those with AHI ≥ 41.6 events/hour (H group, n = 115), the H group had higher body mass index and higher serum triglyceride, and lower the frequency of acute coronary syndrome and lower estimated glomerular filtration rate than did the L group, but no other patient characteristics differed significantly. The H group had a significantly higher incidence of the composite endpoint than did the L group (10.6% vs. 2.6%, P = 0.027). Factors associated with the composite endpoint were identified through multivariate analyses, with AHI, haemoglobin, and left atrial dimension emerging as significant factors (hazard ratio [HR] = 1.02, 95% confidence interval [CI] = 1.00-1.04, P = 0.024; HR = 0.71, 95% CI = 0.54-0.94, P = 0.017; and HR = 1.10, 95% CI = 1.03-1.18, P = 0.006, respectively). Conversely, the minimum SpO2 during PSG (<80%) was not associated with the composite endpoint.

CONCLUSIONS

In patients with SDB who are at risk of heart failure, severe SDB is associated with a high risk of all-cause mortality and the development of heart failure. Additionally, combining cardiac echocardiography and PSG data may improve risk stratification, offering potential assistance for early intervention. Further examination with a validation cohort is necessary.

Sleep Apnea, Autonomic Disturbances, and Blood Pressure Variability

Augmented blood pressure variability has emerged as a quantity predictive of adverse cardiovascular outcomes. Among the range of intrinsic and extrinsic factors shown to increase night-time, circadian, short-term, and long-term blood pressure variations, the presence and severity of obstructive sleep apnea have emerged as one of the most prevalent and potent. Obstructive sleep apnea alters acutely the normal nocturnal equilibrium between sympathetic and parasympathetic tone, magnifying nocturnal blood pressure oscillations, and induces sustained autonomic aftereffects with the capacity to amplify short-term and intersessional blood pressure variabilities. The object of this brief review is to synthesize the current understanding of the potential interrelations between obstructive sleep apnea, the acute and sustained autonomic disturbances that it elicits, and beat-to-beat blood pressure fluctuation during sleep, nocturnal dipping status, and day-to-day blood pressure variability and the consequences of these perturbations for cardiovascular risk.

Obstructive Sleep Apnea and Its Cardiac Implications in the United States: An Age-Stratified Analysis Between Young and Older Adults

BACKGROUND

Obstructive sleep apnea (OSA) is a common sleep disorder associated with cardiovascular risks. This study aimed to assess the prevalence of probable OSA and its relationship with cardiovascular risks and diseases focusing on age-stratified young adults (20-40 years) and older (>40 years).

METHODS AND RESULTS

The study used a cross-sectional design, analyzing data from the National Health and Nutrition Examination Survey conducted between 2013 and 2018, comprising 9887 community-dwelling adults aged ≥20 years. Probable OSA was determined on the basis of self-report of OSA-related symptoms (eg, snoring, gasping/breath cessation while sleeping). Cardiovascular risk factors, including hypertension, diabetes, hyperlipidemia, and metabolic syndrome, were evaluated according to established guidelines. Cardiovascular diseases (CVDs) included self-reported heart conditions, including congestive heart failure, coronary heart disease, angina, heart attacks, and strokes. Individuals with probable OSA showed a significantly higher prevalence of health conditions, including hypertension (adjusted prevalence ratio [aPR], 1.19; P<0.001), diabetes (aPR, 1.17; P: 0.01), metabolic syndrome (aPR, 1.14; P<0.001), heart attack (aPR, 1.63; P<0.01), stroke (aPR, 1.41; P: 0.03), and any CVD event (aPR, 1.36; P: 0.01) after adjusting for relevant factors. Young adults with probable OSA showed higher prevalence rates of any CVD events (aPR, 3.44; P<0.001), hypertension (aPR, 1.45; P<0.001), metabolic syndrome (aPR, 1.25; P<0.001), and angina (aPR, 10.39; P<0.001).

CONCLUSIONS

The study suggests early identification and management of OSA in individuals at risk for CVD. While cross-sectional, it emphasizes that health care providers should recognize OSA as significantly associated with CVDs and its precursor risks in young adults, stressing proactive care and screening to reduce CVD risk in this population.

The Correlation between the Severity of Obstructive Sleep Apnea and Insulin Resistance in a Japanese Population

Background: Repetitive episodes of apnea and hypopnea during sleep in patients with obstructive sleep apnea (OSA) are known to increase the risk of atherosclerosis. Underlying obesity and related disorders, such as insulin resistance, are indirectly related to the development of atherosclerosis. In addition, OSA is independently associated with insulin resistance; however, data regarding this relationship are scarce in Japanese populations. Methods: This study aimed to examine the relationship between the severity of OSA and insulin resistance in a Japanese population. We analyzed the data of consecutive patients who were referred for polysomnography under clinical suspicion of developing OSA and who did not have diabetes mellitus or any cardiovascular disease. Multiple regression analyses were performed to determine the relationship between the severity of OSA and insulin resistance. Results: The data from a total of 483 consecutive patients were analyzed. The median apnea-hypopnea index (AHI) was 40.9/h (interquartile range: 26.5, 59.1) and the median homeostasis model assessment for insulin resistance (HOMA-IR) was 2.00 (interquartile range: 1.25, 3.50). Multiple regression analyses revealed that the AHI, the lowest oxyhemoglobin saturation (SO2), and the percentage of time spent on SO2 < 90% were independently correlated with HOMA-IR (an adjusted R-squared value of 0.01278821, p = 0.014; an adjusted R-squared value of -0.01481952, p = 0.009; and an adjusted R-squared value of 0.018456581, p = 0.003, respectively). Conclusions: The severity of OSA is associated with insulin resistance assessed by HOMA-IR in a Japanese population.

The interrelationships between sleep regularity, obstructive sleep apnea, and hypertension in a middle-aged community population

STUDY OBJECTIVES

Little is known about the interrelationships between sleep regularity, obstructive sleep apnea (OSA) and important health markers. This study examined whether irregular sleep is associated with OSA and hypertension, and if this modifies the known association between OSA and hypertension.

METHODS

Six hundred and two adults (age mean(SD) = 56.96(5.51) years, female = 60%) from the Raine Study who were not evening or night shift workers were assessed for OSA (in-laboratory polysomnography; apnea-hypopnea index ≥ 15 events/hour), hypertension (doctor diagnosed, or systolic blood pressure ≥140 mmHg and/or diastolic ≥90 mmHg) and sleep (wrist actigraphy for ≥5 days). A sleep regularity index (SRI) was determined from actigraphy. Participants were categorized by tertiles as severely irregular, mildly irregular, or regular sleepers. Logistic regression models examined the interrelationships between SRI, OSA and hypertension. Covariates included age, sex, body mass index, actigraphy sleep duration, insomnia, depression, activity, alcohol, smoking, and antihypertensive medication.

RESULTS

Compared to regular sleepers, participants with mildly irregular (OR 1.97, 95% confidence intervals [CI] 1.20 to 3.27) and severely irregular (OR 2.06, 95% CI: 1.25 to 3.42) sleep had greater odds of OSA. Compared to those with no OSA and regular sleep, OSA and severely irregular sleep combined had the highest odds of hypertension (OR 2.34 95% CI: 1.07 to 5.12; p for interaction = 0.02) while those with OSA and regular/mildly irregular sleep were not at increased risk (p for interaction = 0.20).

CONCLUSIONS

Sleep irregularity may be an important modifiable target for hypertension among those with OSA.

Metabolomic profiles of sleep-disordered breathing are associated with hypertension and diabetes mellitus development

Sleep-disordered breathing (SDB) is a prevalent disorder characterized by recurrent episodic upper airway obstruction. Using data from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), we apply principal component analysis (PCA) to seven SDB-related measures. We estimate the associations of the top two SDB PCs with serum levels of 617 metabolites, in both single-metabolite analysis, and a joint penalized regression analysis. The discovery analysis includes 3299 individuals, with validation in a separate dataset of 1522 individuals. Five metabolite associations with SDB PCs are discovered and replicated. SDB PC1, characterized by frequent respiratory events common in older and male adults, is associated with pregnanolone and progesterone-related sulfated metabolites. SDB PC2, characterized by short respiratory event length and self-reported restless sleep, enriched in young adults, is associated with sphingomyelins. Metabolite risk scores (MRSs), representing metabolite signatures associated with the two SDB PCs, are associated with 6-year incident hypertension and diabetes. These MRSs have the potential to serve as biomarkers for SDB, guiding risk stratification and treatment decisions.

Impact of sleep-disordered breathing on overnight changes in arterial stiffness in patients with acute heart failure

Overnight increases in arterial stiffness associated with sleep-disordered breathing may adversely affect patients with acute heart failure. Thus, we investigated overnight changes in arterial stiffness and their association with sleep-disordered breathing in patients hospitalized for acute heart failure. Consecutive patients with acute heart failure were enrolled. All participants underwent overnight full polysomnography following the initial improvement of acute signs and symptoms of acute heart failure. The arterial stiffness parameter, cardio-ankle vascular index (CAVI), was assessed before and after polysomnography. Overall, 60 patients (86.7% men) were analyzed. CAVI significantly increased overnight (from 8.4 ± 1.6 at night to 9.1 ± 1.7 in the morning, P < 0.001) in addition to systolic and diastolic blood pressure (from 114.1 mmHg to 121.6 mmHg, P < 0.001; and from 70.1 mmHg to 78.2 mmHg, P < 0.001, respectively). Overnight increase in CAVI (ΔCAVI ≥ 0) was observed in 42 patients (70%). The ΔCAVI ≥ 0 group was likely to have moderate-to-severe sleep-disordered breathing (i.e., apnea-hypopnea index ≥15, 55.6% vs 80.9%, P = 0.047) and greater obstructive respiratory events (29.4% vs 58.5%, P = 0.041). In multivariable analysis, moderate-to-severe sleep-disordered breathing and greater obstructive respiratory events were independently correlated with an overnight increase in CAVI (P = 0.033 and P = 0.042, respectively). In patients hospitalized for acute heart failure, arterial stiffness, as assessed by CAVI, significantly increased overnight. Moderate-to-severe sleep-disordered breathing and obstructive respiratory events may play an important role in the overnight increase in cardio-ankle vascular index.

Recommended assessment and management of sleep disordered breathing in patients with atrial fibrillation, hypertension and heart failure: Taiwan Society of Cardiology/Taiwan Society of sleep Medicine/Taiwan Society of pulmonary and Critical Care Medicine joint consensus statement

Sleep disordered breathing (SDB) is highly prevalent and may be linked to cardiovascular disease in a bidirectional manner. The Taiwan Society of Cardiology, Taiwan Society of Sleep Medicine and Taiwan Society of Pulmonary and Critical Care Medicine established a task force of experts to evaluate the evidence regarding the assessment and management of SDB in patients with atrial fibrillation (AF), hypertension and heart failure with reduced ejection fraction (HFrEF). The GRADE process was used to assess the evidence associated with 15 formulated questions. The task force developed recommendations and determined strength (Strong, Weak) and direction (For, Against) based on the quality of evidence, balance of benefits and harms, patient values and preferences, and resource use. The resulting 11 recommendations are intended to guide clinicians in determining which the specific patient-care strategy should be utilized by clinicians based on the needs of individual patients.

Obstructive sleep apnea in the patient with atrial fibrillation: current knowledge and remaining uncertainties

PURPOSE OF REVIEW

Obstructive sleep apnea (OSA) is highly prevalent in patients with atrial fibrillation and plays a causal role for OSA in the pathogenesis of atrial fibrillation. The presence of OSA in atrial fibrillation is associated with increased symptom burden and increased risk of hospitalizations. Furthermore, untreated OSA is associated with an increased risk of atrial fibrillation recurrence post ablation or cardioversion, and observational studies suggest that continuous positive airway pressure (CPAP) therapy can attenuate this risk. This review describes our current understanding of the relationship between OSA and atrial fibrillation with an emphasis on emerging evidence.

RECENT FINDINGS

Recent studies have identified novel screening questionnaires, which may be superior to traditional questionnaires in identifying OSA in atrial fibrillation populations. Significant night-to-night variability in OSA severity has been shown in atrial fibrillation patients, which has implications for diagnostic testing. While several small, randomized control trials (RCTs) have not shown CPAP therapy to be effective in reducing atrial fibrillation burden, one RCT did show CPAP can attenuate the atrial substrate with implications for long-term outcomes.

SUMMARY

Further RCTs, appropriately powered, and focused on well defined cohorts, are required to guide management decisions regarding screening and treatment of OSA in atrial fibrillation populations.

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.

Sleep apnea severity in patients undergoing atrial fibrillation ablation: Home sleep apnea-test and polysomnography comparison

Background

Sleep apnea (SA) is highly prevalent and should be treated in patients referred for catheter ablation (CA) of atrial fibrillation (AF). Watch-type peripheral arterial tonometry (WP) for home SA testing has demonstrated a high correlation of the apnea-hypopnea index (AHI) with Polysomnography (PSG), but the evidence of its accuracy in AF patients is not adequate.

Methods

This study was conducted under a retrospective, single-center, observational design. We included 464 consecutive AF patients (age 65 ± 11 years, 76.5% male, 45.0% paroxysmal-AF) who received both WP and PSG during the periprocedural period of the CA. We compared the AHI using the WP (WP-AHI) to that using PSG (PSG-AHI).

Results

The WP-AHI was 25.9 ± 12.7 and PSG-AHI 31.4 ± 18.9 (r = .48). Among 325 patients with a WP-AHI < 30, 116 (35.7%) exhibited a PSG-AHI ≥ 30. Only 12.5% of the patients were indicated for continuous positive airway pressure (CPAP) treatment only by the WP-AHI, while 70.9% were indicated for CPAP by the PSG-AHI according to the Japanese health insurance system. The best cut-off value of the WP-AHI was 18.1 to predict a PSG-AHI ≥ 20 with an area under the curve of 0.72 (95% confidence interval, 0.67-0.76).

Conclusions

The WP-AHI and PSG-AHI were weakly correlated in AF patients receiving CA. About one-third of the patients with moderate SA using the WP was diagnosed with severe SA evaluated by PSG. The majority required PSG for the CPAP indication.

Metabolomic Profiles of Sleep-Disordered Breathing are Associated with Hypertension and Diabetes Mellitus Development: the HCHS/SOL

Sleep-disordered breathing (SDB) is a prevalent disorder characterized by recurrent episodic upper airway obstruction. In a dataset from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), we applied principal component analysis (PCA) on seven measures characterizing SDB-associated respiratory events. We estimated the association of the top two SDB PCs with serum levels of 617 metabolites, in both single-metabolite analysis, and a joint, penalized regression analysis using the least absolute shrinkage and selection operator (LASSO). Discovery analysis included n = 3,299 HCHS/SOL individuals; associations were validated in a separate dataset of n = 1,522 HCHS/SOL individuals. Seven metabolite associations with SDB PCs were discovered and replicated. Metabolite risk scores (MRSs) developed based on LASSO association results and representing metabolite signatures associated with the two SDB PCs were associated with 6-year incident hypertension and incident diabetes. MRSs have the potential to serve as biomarkers for SDB, guiding risk stratification and treatment decisions.

Determinants of Severe Nocturnal Hypoxemia in Adults with Chronic Thromboembolic Pulmonary Hypertension and Sleep-Related Breathing Disorders

OBJECTIVES

We aimed to investigate the occurrence of sleep-related breathing disorders (SRBDs) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) and addressed the effect of pulmonary hemodynamics and SRBD indices on the severity of nocturnal hypoxemia (NH).

METHODS

An overnight polysomnography (PSG) was conducted in patients with CTEPH, who were eligible for pulmonary endarterectomy. Pulmonary hemodynamics (mean pulmonary arterial pressure (mPAP), pulmonary arterial wedge pressure (PAWP), pulmonary vascular resistance (PVR) measured with right heart catheterization (RHC)), PSG variables (apnea-hypopnea index (AHI)), lung function and carbon monoxide diffusion capacity (DLCO) values, as well as demographics and comorbidities were entered into a logistic regression model to address the determinants of severe NH (nocturnal oxyhemoglobin saturation (SpO₂) < 90% under >20% of total sleep time (TST)). SRBDs were defined as obstructive sleep apnea (OSA; as an AHI ≥ 15 events/h), central sleep apnea with Cheyne-Stokes respiration (CSA-CSR; CSR pattern ≥ 50% of TST), obesity hypoventilation syndrome (OHS), and isolated sleep-related hypoxemia (ISRH; SpO₂ < 88% under >5 min without OSA, CSA, or OHS).

RESULTS

In all, 50 consecutive patients (34 men and 16 women; mean age 54.0 (SD 15.1) years) were included. The average mPAP was 43.8 (SD 16.8) mmHg. SRBD was observed in 40 (80%) patients, of whom 27 had OSA, 2 CSA-CSR, and 11 ISRH. None had OHS. Severe NH was observed in 31 (62%) patients. Among the variables tested, age (odds ratio (OR) 1.08, 95% confidence interval [CI] 1.01-1.15; p = 0.031), mPAP (OR 1.11 [95% CI 1.02-1.12; p = 0.012]), and AHI (OR 1.17 [95% CI 1.02-1.35; p = 0.031]) were independent determinants of severe NH.

CONCLUSIONS

Severe NH is highly prevalent in patients with CTEPH. Early screening for SRBDs and intervention with nocturnal supplemental oxygen and/or positive airway pressure as well as pulmonary endarterectomy may reduce adverse outcomes in patients with CTEPH.

Associations between air pollution, intracellular-to-extracellular water distribution, and obstructive sleep apnea manifestations

Background

Exposure to air pollution may be a risk factor for obstructive sleep apnea (OSA) because air pollution may alter body water distribution and aggravate OSA manifestations.

Objectives

This study aimed to investigate the mediating effects of air pollution on the exacerbation of OSA severity through body water distribution.

Methods

This retrospective study analyzed body composition and polysomnographic data collected from a sleep center in Northern Taiwan. Air pollution exposure was estimated using an adjusted nearest method, registered residential addresses, and data from the databases of government air quality motioning stations. Next, regression models were employed to determine the associations between estimated air pollution exposure levels (exposure for 1, 3, 6, and 12 months), OSA manifestations (sleep-disordered breathing indices and respiratory event duration), and body fluid parameters (total body water and body water distribution). The association between air pollution and OSA risk was determined.

Results

Significant associations between OSA manifestations and short-term (1 month) exposure to PM_2.5 and PM₁₀ were identified. Similarly, significant associations were identified among total body water and body water distribution (intracellular-to-extracellular body water distribution), short-term (1 month) exposure to PM_2.5 and PM₁₀, and medium-term (3 months) exposure to PM₁₀. Body water distribution might be a mediator that aggravates OSA manifestations, and short-term exposure to PM_2.5 and PM₁₀ may be a risk factor for OSA.

Conclusion

Because exposure to PM_2.5 and PM₁₀ may be a risk factor for OSA that exacerbates OSA manifestations and exposure to particulate pollutants may affect OSA manifestations or alter body water distribution to affect OSA manifestations, mitigating exposure to particulate pollutants may improve OSA manifestations and reduce the risk of OSA. Furthermore, this study elucidated the potential mechanisms underlying the relationship between air pollution, body fluid parameters, and OSA severity.

Atherosclerotic plaque in individuals without known cardiovascular disease but with established obstructive sleep apnea and at high risk of obstructive sleep apnea

Objectives

In a large U.S. cohort free of CVD evaluated by coronary computed CT angiography, we aimed to assess the association between established / high risk of Obstructive Sleep Apnea (OSA) and coronary plaque.

Background

There are limited data available depicting the association between established / high risk of OSA and the presence of coronary plaque in a population-based sample free from CVD.

Methods

Cross-sectional data from 2359 participants enrolled in the Miami Heart Study (MiHeart) who underwent coronary CT angiography was used for this study. The Berlin questionnaire was used to stratify patients as having high or low risk of OSA. Multiple multivariable logistic regression analyses were conducted to investigate the association between the risk of developing OSA with the presence, volume, and composition of plaque.

Results

According to the Berlin questionnaire, 1559 participants were (66.1%) at low risk of OSA and 800 patients (33.9%) with established / high risk of OSA. Plaque characterization on CCTA revealed a greater incidence of any possible plaque composition in the established / high risk of OSA category (59.6% vs. 43.5%) compared to the low risk of OSA cohort. In logistic regression models, after adjusting for demographics and cardiovascular risk factors, a significant association could still be noted between established / high risk of OSA and any coronary plaque on CCTA (OR=1.31, CI 1.05, 1.63, p = 0.016). Subgroup analysis in the Hispanic population also portrayed a significant association between established / high risk of OSA and the presence of coronary plaque on CCTA (OR = 1.55 CI 1.13, 2.12, p = 0.007).

Conclusion

After accounting for CVD risk factors, individuals at established / high risk of OSA have a higher likelihood of the presence of coronary plaque. Future studies should focus on OSA presence or risk, OSA severity, and the longitudinal consequences of coronary atherosclerosis.

Network pharmacology and molecular docking prediction, combined with experimental validation to explore the potential mechanism of Qishen Yiqi pills against HF-related cognitive dysfunction

ETHNOPHARMACOLOGICAL RELEVANCE

Qishen Yiqi Pills (QSYQ) is a classical herbal formula for treating heart failure (HF) and has potential efficacy in improving cognitive function. The latter is one of the most common complications in patients with HF. However, there is no study on treating HF-related cognitive dysfunction by QSYQ.

AIMS OF THE STUDY

The study aims to investigate the effect and mechanism of QSYQ on treating post-HF cognitive dysfunction based on network pharmacology and experimental validation.

MATERIALS AND METHODS

Network pharmacology analysis and molecular docking was used to explore endogenous targets of QSYQ in treating cognitive impairment. Ligation of the anterior descending branch of the left coronary artery and sleep deprivation (SD) were used to induce HF-related cognitive dysfunction in rats. The efficacy and potential signal targets of QSYQ were then verified by functional evaluation, pathological staining, and molecular biology experiments.

RESULTS

384 common targets were identified by intersecting QSYQ 'compound targets' and 'cognitive dysfunction' disease targets. KEGG analysis showed these targets were enriched to the cAMP signal, and four marks responsible for regulating the cAMP signal were successfully docked with core compounds of QSYQ. Animal experiments demonstrated that QSYQ significantly ameliorated cardiac function and cognitive function in rats suffering from HF and SD, inhibited the reduction of cAMP and BDNF content, reversed the upregulation of PDE4 and downregulation of CREB, suppressed the loss of neurons, and restored the expression of synaptic protein PSD95 in the hippocampus.

CONCLUSION

This study clarified that QSYQ could improve HF-related cognitive dysfunction by modulating cAMP-CREB-BDNF signals. It provides a rich basis for the potential mechanism of QSYQ in the treatment of heart failure with cognitive dysfunction.

Interaction of positive airway pressure mask magnets with cardiac implantable electronic devices

STUDY OBJECTIVES

To evaluate for potential interactions between magnetic positive airway pressure (mPAP) masks and cardiac implantable electronic devices (CIEDs) for patients with sleep apnea.

METHODS

Adult patients with a CIED who used an mPAP mask were recruited from our sleep clinic to undergo a safety visit at our pacemaker clinic. We tested whether the mPAP interacted with the implanted device at home during normal use and in the clinic during simulated normal use and with direct contact. The magnetic field strength of 6 mPAP masks was tested with a gaussmeter.

RESULTS

Of 13 patients tested, 1 (8%), wearing a full face mask (ResMed AirFit F30 [ResMed, San Diego, California]), had a magnet response event (interaction) with direct contact, but no interactions were identified during normal or simulated normal use in any patient. The magnetic field strength of the mPAP masks increased the closer the mask got to the CIED, from 0.4 mT (4 G) at the mask manufacturer's recommended 5.1-cm (2-inch) distance from an implanted medical device up to 291 mT (2,910 G) at 0 cm (0 inches; direct contact).

CONCLUSIONS

An mPAP mask may interact with a CIED if placed directly on the skin overlying the CIED. The use of Philips Respironics (Philips, Cambridge, Massachusetts) mPAP masks is now contraindicated in patients with a CIED. Until additional studies are conducted to better document the risks and benefits of mPAP masks, we recommend discouraging patients with CIEDs from using any mPAP mask.

CITATION

Ruoff CM, Tashman YS, Cheema KPK, et al. Interaction of positive airway pressure mask magnets with cardiac implantable electronic devices. J Clin Sleep Med. 2023;19(5):941-946.

The Usefulness of Questionnaires in Assessing the Risk of Obstructive Sleep Apnea in Patients in the Managed Care after Acute Myocardial Infarction Program-The Results of a Cross-Sectional Study

Obstructive sleep apnea (OSA) worsens prognosis after myocardial infarction (MI) but often remains undiagnosed. The study aimed to evaluate the usefulness of questionnaires in assessing the risk of OSA in patients participating in managed care after an acute myocardial infarction program. Study group: 438 patients (349 (79.7%) men) aged 59.92 ± 10.92, hospitalized in the day treatment cardiac rehabilitation department 7-28 days after MI. OSA risk assessment: A 4-variable screening tool (4-V), STOP-BANG questionnaire, Epworth sleepiness scale (ESS), and adjusted neck circumference (ANC). The home sleep apnea testing (HSAT) was performed on 275 participants. Based on four scales, a high risk of OSA was found in 283 (64.6%) responders, including 248 (56.6%) based on STOP-BANG, 163 (37.5%) based on ANC, 115 (26.3%) based on 4-V, and 45 (10.3%) based on ESS. OSA was confirmed in 186 (68.0%) participants: mild in 85 (30.9%), moderate in 53 (19.3%), and severe in 48 (17.5%). The questionnaires' sensitivity and specificity in predicting moderate-to-severe OSA were: for STOP-BANG-79.21% (95% confidence interval; CI 70.0-86.6) and 35.67% (95% CI 28.2-43.7); ANC-61.39% (95% CI 51.2-70.9) and 61.15% (95% CI 53.1-68.8); 4-V-45.54% (95% CI 35.6-55.8) and 68.79% (95% CI 60.9-75.9); ESS-16.83% (95% CI 10.1-25.6) and 87.90% (95% CI 81.7-92.6). OSA is common in post-MI patients. The ANC most accurately estimates the risk of OSA eligible for positive airway pressure therapy. The sensitivity of the ESS in the post-MI population is insufficient and limits this scale's usefulness in risk assessment and qualification for treatment.

Mattress-Based Non-Influencing Sleep Apnea Monitoring System

A mattress-type non-influencing sleep apnea monitoring system was designed to detect sleep apnea-hypopnea syndrome (SAHS). The pressure signals generated during sleep on the mattress were collected, and ballistocardiogram (BCG) and respiratory signals were extracted from the original signals. In the experiment, wavelet transform (WT) was used to reduce noise and decompose and reconstruct the signal to eliminate the influence of interference noise, which can directly and accurately separate the BCG signal and respiratory signal. In feature extraction, based on the five features commonly used in SAHS, an innovative respiratory waveform similarity feature was proposed in this work for the first time. In the SAHS detection, the binomial logistic regression was used to determine the sleep apnea symptoms in the signal segment. Simulation and experimental results showed that the device, algorithm, and system designed in this work were effective methods to detect, diagnose, and assist the diagnosis of SAHS.

Interactions between Sleep Apnea and Coronary Artery Disease on the Incidence of Sudden Cardiac Arrest: A Multi-Center Case-Control Study

PURPOSE

Sleep apnea (SA) is a risk factor for coronary artery disease (CAD), and SA and CAD increase the incidence of sudden cardiac arrest (SCA). This study aimed to investigate the effect of SA on the incidence of SCA and explore the effect of varying degrees of SA with or without CAD on the incidence of SCA.

MATERIALS AND METHODS

This prospective multi-center, case-control study was performed using the phase II Cardiac Arrest Pursuit Trial with Unique Registry and Epidemiologic Surveillance (CAPTURES-II) database for SCA cases and community-based controls in Korea. The matching ratio of cases to controls was 1:1, and they were randomly matched within demographics, including age, sex, and residence. The primary variable was a history of SA, and the second variable was a history of CAD. We conducted a conditional logistic regression analysis to estimate the effect of SA and CAD on the SCA risk, and an interaction analysis between SA and CAD.

RESULTS

SA was associated with an increased risk of SCA [adjusted odds ratio (AOR) (95% confidence interval, CI): 1.54 (1.16-2.03)], and CAD was associated with an increased risk of SCA [AOR (95% CI): 3.94 (2.50-6.18)]. SA was a risk factor for SCA in patients without CAD [AOR (95% CI): 1.62 (1.21-2.17)], but not in patients with CAD [AOR (95% CI): 0.56 (0.20-1.53)].

CONCLUSION

In the general population, SA is risk factor for SCA only in patients without CAD. Early medical intervention for SA, especially in populations without pre-existing CAD, may reduce the SCA risk. ClinicalTrials.gov (NCT03700203).

Development and validation of a metabolite index for obstructive sleep apnea across race/ethnicities

Obstructive sleep apnea (OSA) is a common disorder characterized by recurrent episodes of upper airway obstruction during sleep resulting in oxygen desaturation and sleep fragmentation, and associated with increased risk of adverse health outcomes. Metabolites are being increasingly used for biomarker discovery and evaluation of disease processes and progression. Studying metabolomic associations with OSA in a diverse community-based cohort may provide insights into the pathophysiology of OSA. We aimed to develop and replicate a metabolite index for OSA and identify individual metabolites associated with OSA. We studied 219 metabolites and their associations with the apnea hypopnea index (AHI) and with moderate-severe OSA (AHI ≥ 15) in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) (n = 3507) using two methods: (1) association analysis of individual metabolites, and (2) least absolute shrinkage and selection operator (LASSO) regression to identify a subset of metabolites jointly associated with OSA, which was used to develop a metabolite index for OSA. Results were validated in the Multi-Ethnic Study of Atherosclerosis (MESA) (n = 475). When assessing the associations with individual metabolites, we identified seven metabolites significantly positively associated with OSA in HCHS/SOL (FDR p < 0.05), of which four associations-glutamate, oleoyl-linoleoyl-glycerol (18:1/18:2), linoleoyl-linoleoyl-glycerol (18:2/18:2) and phenylalanine, were replicated in MESA (one sided-p < 0.05). The OSA metabolite index, composed of 14 metabolites, was associated with a 50% increased risk for moderate-severe OSA (OR = 1.50 [95% CI 1.21-1.85] per 1 SD of OSA metabolite index, p < 0.001) in HCHS/SOL and 55% increased risk (OR = 1.55 [95% CI 1.10-2.20] per 1 SD of OSA metabolite index, p = 0.013) in MESA, both adjusted for demographics, lifestyle, and comorbidities. Similar albeit less significant associations were observed for AHI. Replication of the metabolite index in an independent multi-ethnic dataset demonstrates the robustness of metabolomic-based OSA index to population heterogeneity. Replicated metabolite associations may provide insights into OSA-related molecular and metabolic mechanisms.

Screening for obstructive sleep apnea before coronary angiography

INTRODUCTION

The prevalence of obstructive sleep apnea (OSA) in patients with suspected coronary heart disease (CHD) is yet to be clarified. This study aimed to investigate the prevalence of OSA before coronary angiography (CAG).

METHODS

We retrospectively evaluated patients with suspected CHD admitted to the Department of Geriatric Cardiology of our hospital between July 2019 and July 2021. OSA was screened using the level III home sleep apnea test before CAG. The prevalence of OSA was then compared between the CHD and non-CHD groups. CHD severity was determined using the Gensini score of CAG results, and OSA severity was graded using the apnea-hypopnea index (AHI).

RESULTS

Among the 327 patients, 211 had CHD. In total, 264 patients were diagnosed with OSA (80.7%) (184 patients, CHD group [87.2%]; 80 patients, non-CHD group [69.0%]). The CHD group had a significantly higher prevalence of OSA (P < 0.01) and higher AHI (CHD group 18.76 ± 14.94, non-CHD group 11.56 ± 10.67, P < 0.01). The Gensini score was positively correlated with OSA severity in patients with CHD, and AHI ≥ 20 was a risk factor for CHD (odds ratio: 1.961, 95% confidence interval: 1.065-3.608, P < 0.05).

CONCLUSION

OSA screening before CAG revealed a higher prevalence in CHD patients than in non-CHD patients. The degree of coronary artery obstruction is positively correlated with AHI, and AHI ≥ 20 is a risk factor for CHD. Therefore, attention should be paid to OSA screening and management before CAG in patients with suspected CHD.

Positive airway pressure therapy in heart failure patients comorbid with obstructive sleep apnea: Cardiovascular outcomes and nighttime-duration effect

BACKGROUND

Comorbidity of obstructive sleep apnea (OSA) and heart failure (HF) is becoming increasingly common. This is a global analysis of positive airway pressure (PAP) efficacy for the cardiovascular outcomes in those HF Patients with comorbid OSA.

METHODS

Related randomized controlled trials were included. Analysed indicators covered primary outcomes (cardiac function, motor ability and life quality) and secondary outcomes (blood pressure and OSA-accompanying symptoms). Weighted mean difference was used to analyse the PAP-control difference in different experimental phases and the baseline-post difference in different groups.

RESULTS

Compared with control group, PAP was associated with a 3.48% increase in left ventricle ejection fraction (LVEF) (p < .00001) and little decrease in heart rate (HR) (p = .67). Over 6 h of mean nighttime use was associated with a greater increase in LVEF of 5.21% (p = .0002) and a significant reduction in HR of 3.81 bpm (p = .03). There was no significant difference between PAP and control group in their association with change in motor ability and life quality. Besides, PAP was associated with a 13.08 mm Hg decrease in systolic blood pressure and great improvements in OSA-accompanying symptoms: Apnea-Hypopnea Index, -23.73 e/h; mean oxygen saturation, 1.86%; minimum oxygen saturation, 8.78%; Epworth Sleepiness Scale, -1.39 point; arousal index, -16.41 e/h. There was also no significant difference in diastolic blood pressure.

CONCLUSIONS

Positive airway pressure treatment improves cardiac function in HF patients with comorbid OSA, but the improved magnitude is associated with the duration of nighttime use rather than the duration of treatment.

Practice recommendations for the role of physiotherapy in the management of sleep disorders: the 2022 Brazilian Sleep Association Guidelines

This clinical guideline supported by the Brazilian Sleep Association comprises a brief history of the development of Brazilian sleep physiotherapy, outlines the role of the physiotherapist as part of a sleep health team, and describes the clinical guidelines in respect of the management of some sleep disorders by the physiotherapist (including sleep breathing disorders, i.e., obstructive sleep apnea, central sleep apnea, upper airway resistance syndrome, hypoventilation syndromes and overlap syndrome, and pediatric sleep breathing disorders; sleep bruxism; circadian rhythms disturbances; insomnia; and Willis-Ekbom disease/periodic limb movement disorder. This clinical practice guideline reflects the state of the art at the time of publication and will be reviewed and updated as new information becomes available.

Diagnostic Efficacy of Ultra-Short Term HRV Analysis in Obstructive Sleep Apnea

Heart rate variability (HRV) is the standard method for assessing autonomic nervous system (ANS) activity and is considered a surrogate marker for sympathetic overactivity in obstructive sleep apnea (OSA). Although HRV features are usually obtained from the short-term segment method, it is impossible to evaluate rapid dynamic changes in ANS activity. Herein, we propose the ultra-short-term analysis to detect the balance of ANS activity in patients with OSA. In 1021 OSA patients, 10 min HRV target datasets were extracted from polysomnographic data and analyzed by shifting the 2 min (ultra-short-term) and 5 min (short-term) segments. We detected frequency-domain parameters, including total power (Ln TP), very low frequency (Ln VLF), low frequency (Ln LF), and high frequency (Ln HF). We found that overall HRV feature alterations indicated sympathetic overactivity dependent on OSA severity, and that this was more pronounced in the ultra-short-term methodology. The apnea-hypopnea index, oxygen desaturation index, and Epworth sleepiness scale correlated with increased sympathetic activity and decreased parasympathetic activity, regardless of the methodology. The Bland-Altman plot analyses also showed a higher agreement of HRV features between the two methodologies. This study suggests that ultra-short-term HRV analysis may be a useful method for detecting alterations in ANS function in OSA patients.

A Prediction Nomogram Combining Epworth Sleepiness Scale and Other Clinical Parameters to Predict Obstructive Sleep Apnea in Patients with Hypertension

Background

Obstructive sleep apnea (OSA) is common in patients with hypertension. Nonetheless, OSA is underdiagnosed despite considerable evidence of the association between OSA and adverse health outcomes. This study developed and validated a clinical nomogram to predict OSA in patients with hypertension based on the Epworth Sleepiness Scale (ESS) score and OSA-related parameters.

Methods

A total of 347 hypertensive patients with suspected OSA were retrospectively enrolled and randomly assigned to a training set and a validation set at 70 : 30 (N = 242/N = 105) ratio. OSA was diagnosed through sleep monitoring and was defined as an apnea-hypopnea index ≥5 events/h. Using the least absolute shrinkage and selection operator regression model, we identified potential predictors of OSA and constructed a nomogram model in the training set. The predictive performance of the nomogram was assessed and validated by discrimination and calibration. The nomogram was also compared with ESS scores according to decision curve analysis (DCA), integrated discrimination index (IDI), and net reclassification index (NRI).

Results

ESS scores, body mass index, neck circumference, snoring, and observed apnea predicted OSA are considered. The nomogram showed similar discrimination between the training set (AUC: 0.799, 95% CI: 0.743–0.847) and validation set (AUC: 0.766, 95% CI: 0.673–0.843) and good calibration in the training (P=0.925 > 0.05) and validation (P=0.906 > 0.05) sets. Compared with the predictive value of the ESS, the nomogram was clinically useful and significantly improved reclassification accuracy (NRI: 0.552, 95% CI: 0.282–0.822, P < 0.001; IDI: 0.088, 95% CI: 0.045–0.133, P < 0.001) at a probability threshold of >42%.

Conclusions

We developed a novel OSA prediction nomogram based on ESS scores and OSA-related parameters. This nomogram may help improve clinical decision-making, especially in communities and primary clinics, where polysomnography is unavailable.

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.

Obstructive sleep apnea risk and hearing impairment among occupational noise-exposed male workers

This study aimed to investigate the association between obstructive sleep apnea (OSA) risk and hearing impairment among workers exposed to occupational noise. A cross-sectional study was conducted among 607 healthy male workers at a tire-manufacturing factory. The subjects underwent audiometric testing, and their OSA risk was examined based on the STOP-Bang questionnaire. Hearing impairment was defined as a hearing threshold >25 dB hearing level (HL) in any frequency of 1, 2, 3 and 4 kHz in either ear. High OSA risk was defined as a STOP-bang score of ≥3. Hearing thresholds at 1, 2, 3 and 4 kHz in both ears were significantly higher among workers with high OSA risk than among those with low OSA risk after adjusting for confounders. Multiple logistic regression analysis examining the association of OSA risk and STOP-Bang score with hearing impairment revealed an odds ratio of 1.738 (95% confidence interval [CI] 1.113-2.713, p = 0.015) and 1.256 (95% CI 1.031-1.529, p = 0.023), respectively, after adjusting for confounders. In addition, when the hearing impairment was reclassified into high- and low-frequency hearing impairment, a statistically significant OR was seen for high-frequency hearing impairment. In conclusion, high OSA risk was associated with hearing impairment in occupational noise-exposed workers, especially in the high-frequency range of 3 and 4 kHz. More efforts are required to improve the management of OSA and its risk factors to preserve hearing in occupational noise-exposed workers.

Sympathetic and Vagal Nerve Activity in COPD: Pathophysiology, Presumed Determinants and Underappreciated Therapeutic Potential

This article explains the comprehensive state of the art assessment of sympathetic (SNA) and vagal nerve activity recordings in humans and highlights the precise mechanisms mediating increased SNA and its corresponding presumed clinical determinants and therapeutic potential in the context of chronic obstructive pulmonary disease (COPD). It is known that patients with COPD exhibit increased muscle sympathetic nerve activity (MSNA), as measured directly using intraneural microelectrodes—the gold standard for evaluation of sympathetic outflow. However, the underlying physiological mechanisms responsible for the sympathoexcitation in COPD and its clinical relevance are less well understood. This may be related to the absence of a systematic approach to measure the increase in sympathetic activity and the lack of a comprehensive approach to assess the underlying mechanisms by which MSNA increases. The nature of sympathoexcitation can be dissected by distinguishing the heart rate increasing properties (heart rate and blood pressure variability) from the vasoconstrictive drive to the peripheral vasculature (measurement of catecholamines and MSNA) (Graphical Abstract Figure 1). Invasive assessment of MSNA to the point of single unit recordings with analysis of single postganglionic sympathetic firing, and hence SNA drive to the peripheral vasculature, is the gold standard for quantification of SNA in humans but is only available in a few centres worldwide because it is costly, time consuming and requires a high level of training. A broad picture of the underlying pathophysiological determinants of the increase in sympathetic outflow in COPD can only be determined if a combination of these tools are used. Various factors potentially determine SNA in COPD (Graphical Abstract Figure 1): Obstructive sleep apnoea (OSA) is highly prevalent in COPD, and leads to repeated bouts of upper airway obstructions with hypoxemia, causing repetitive arousals. This probably produces ongoing sympathoexcitation in the awake state, likely in the “blue bloater” phenotype, resulting in persistent vasoconstriction. Other variables likely describe a subset of COPD patients with increase of sympathetic drive to the heart, clinically likely in the “pink puffer” phenotype. Pharmacological treatment options of increased SNA in COPD could comprise beta blocker therapy. However, as opposed to systolic heart failure a similar beneficial effect of beta blocker therapy in COPD patients has not been shown. The point is made that although MSNA is undoubtedly increased in COPD (probably independently from concomitant cardiovascular disease), studies designed to determine clinical improvements during specific treatment will only be successful if they include adequate patient selection and translational state of the art assessment of SNA. This would ideally include intraneural recordings of MSNA and—as a future perspective—vagal nerve activity all of which should ideally be assessed both in the upright and in the supine position to also determine baroreflex function.

Effect of continuous positive airway pressure treatment on ambulatory blood pressures in high-risk sleep apnea patients: a randomized controlled trial

STUDY OBJECTIVES

The long-term effect of continuous positive airway pressure (CPAP) on 24-hour blood pressure (BP) in high-risk patients with obstructive sleep apnea (OSA) is uncertain. We aimed to determine the effect of CPAP treatment on ambulatory BP in individuals with moderate or severe OSA and cardiovascular disease (CVD) or multiple CVD risk factors without severe sleepiness.

METHODS

In this randomized, controlled, parallel group study, 169 participants were randomly assigned to CPAP treatment or the control group. The primary outcome was the change in mean 24-hour systolic BP between groups from baseline to the average of 6 and 12 month measurements using mixed effect linear regression models.

RESULTS

The 24-hour systolic BP did not significantly differ by group, although there was a trend of decrease in the CPAP group (treatment effect -2.7 mm Hg [95% confidence interval -5.9 to 0.6]; P=0.105) compared with control. CPAP had the greatest effect on nighttime systolic BP (treatment effect -5.9 mm Hg [95% confidence interval -9.9 to -1.9]; P=0.004). Similar improvements in other nocturnal BP indices were observed.

CONCLUSIONS

In high risk patients with moderate-severe OSA without severe sleepiness, CPAP resulted in modest BP improvements over 6 to 12 months of follow-up, with possibly larger effects for nocturnal BP. Use of office blood pressure may under-estimate the effect of CPAP on BP profile in patients with OSA.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Title: Sleep Apnea Intervention for Cardiovascular Disease Reduction; Identifier: NCT01261390; URL: https://clinicaltrials.gov/ct2/show/NCT01261390.

Association between Frequency of Central Respiratory Events and Clinical Outcomes in Heart Failure Patients with Sleep Apnea

Heart failure (HF) is a progressive cardiac disorder associated with high mortality and morbidity. Previous studies have shown that sleep apnea (SA) is associated with a poor prognosis in HF patients. When HF coexists with SA, both central and obstructive respiratory events often occur. However, few studies have investigated the association between the frequency of central respiratory events coexisting with obstructive events and clinical outcomes in patients with HF and SA. This was a retrospective observational study. Patients with stable HF, defined as a left ventricular ejection fraction of ≤50%, New York Heart Association class ≥ II, and SA (apnea-hypopnea index of ≥15/h on overnight polysomnography) were enrolled. The primary endpoint was a composite of all-cause death and hospitalization for HF. Overall, 144 patients were enrolled. During a period of 23.4 ± 16 months, 45.8% of patients experienced the outcome. The cumulative event-free survival rates were higher in the central SA-predominant group. Multivariate analyses showed that a greater percentage of central respiratory events was associated with an increased risk of clinical outcomes. In patients with HF and SA, the frequency of central respiratory events was an independent factor for all-cause death and hospitalization for HF.

A portrait of obstructive sleep apnea risk factors in 27,210 middle-aged and older adults in the Canadian Longitudinal Study on Aging

Determining the prevalence and characteristics of individuals susceptible to present with obstructive sleep apnea (OSA) is essential for developing targeted and efficient prevention and screening strategies. We included 27,210 participants aged ≥45 years old (50.3% women) from the Canadian Longitudinal Study on Aging. Using the STOP questionnaire combined to the percentage of body fat (%BF), we estimated the prevalence of individuals at high-risk for OSA in a sex and age-specific manner, and tested the relation with comorbidities, menopause and systemic inflammation. The prevalence was 17.5%, and was lower in women (13.1%) than in men (21.9%). A high level of high-sensitivity C-reactive protein was the strongest factor associated with OSA risk and this association was 1.3-2.3 times higher in women than in men. OSA risk increased with age, cardiovascular diseases, diabetes mellitus, anxio-depressive symptoms, asthma and arthritis. In women, post-menopausal status was associated with a high OSA risk. Nearly 1 adult out of 5 older than 45 is at risk for OSA in Canada. Comorbidities, menopause and systemic inflammation, more than age, explain increased OSA prevalence. Considering this high prevalence and associations with medical and mental comorbidities, health care practitioners should incorporate systematic OSA screening in their clinical procedures.

Diabetes and cardiovascular diseases are associated with the worsening of intermittent hypoxaemia

Intermittent hypoxaemia is a risk factor for numerous diseases. However, the reverse pathway remains unclear. Therefore, we investigated whether pre-existing hypertension, diabetes or cardiovascular diseases are associated with the worsening of intermittent hypoxaemia. Among the included 2,535 Sleep Heart Health Study participants, hypertension (n = 1,164), diabetes (n = 170) and cardiovascular diseases (n = 265) were frequently present at baseline. All participants had undergone two polysomnographic recordings approximately 5.2 years apart. Covariate-adjusted linear regression analyses were utilized to investigate the difference in the severity of intermittent hypoxaemia at baseline between each comorbidity group and the group of participants free from all comorbidities (n = 1,264). Similarly, we investigated whether the pre-existing comorbidities are associated with the progression of intermittent hypoxaemia. Significantly higher oxygen desaturation index (β = 1.77 [95% confidence interval: 0.41-3.13], p = 0.011), desaturation severity (β = 0.07 [95% confidence interval: 0.00-0.14], p = 0.048) and desaturation duration (β = 1.50 [95% confidence interval: 0.31-2.69], p = 0.013) were observed in participants with pre-existing cardiovascular diseases at baseline. Furthermore, the increase in oxygen desaturation index (β = 3.59 [95% confidence interval: 1.78-5.39], p < 0.001), desaturation severity (β = 0.08 [95% confidence interval: 0.02-0.14], p = 0.015) and desaturation duration (β = 2.60 [95% confidence interval: 1.22-3.98], p < 0.001) during the follow-up were higher among participants with diabetes. Similarly, the increase in oxygen desaturation index (β = 2.73 [95% confidence interval: 1.15-4.32], p = 0.001) and desaturation duration (β = 1.85 [95% confidence interval: 0.62-3.08], p = 0.003) were higher among participants with cardiovascular diseases. These results suggest that patients with pre-existing diabetes or cardiovascular diseases are at increased risk for an expedited worsening of intermittent hypoxaemia. As intermittent hypoxaemia is an essential feature of sleep apnea, these patients could benefit from the screening and follow-up monitoring of sleep apnea.

Asian Pacific Society of Cardiology Consensus Statements on the Diagnosis and Management of Obstructive Sleep Apnoea in Patients with Cardiovascular Disease

Obstructive sleep apnoea (OSA) is strongly associated with cardiovascular disease (CVD). However, evidence supporting this association in the Asian population is scarce. Given the differences in the epidemiology of CVD and cardiovascular risk factors, as well as differences in the availability of healthcare resources between Asian and Western countries, an Asian Pacific Society of Cardiology (APSC) working group developed consensus recommendations on the management of OSA in patients with CVD in the Asia-Pacific region. The APSC expert panel reviewed and appraised the available evidence using the Grading of Recommendations Assessment, Development, and Evaluation system. Consensus recommendations were developed and put to an online vote. Consensus was reached when 80% of votes for a given recommendation were in support of 'agree' or 'neutral.' The resulting statements provide guidance on the assessment and treatment of OSA in patients with CVD in the Asia-Pacific region. The APSC hopes for these recommendations to pave the way for screening, early diagnosis and treatment of OSA in the Asia-Pacific region.