Obstructive Sleep Apnea in Cardiovascular Disease: A Review of the Literature and Proposed Multidisciplinary Clinical Management Strategy

Are noradrenergics combined with antimuscarinics the future pharmacologic treatment for obstructive sleep apnea? A systematic review and meta-analysis of randomized controlled trials

PURPOSE

Noradrenergics and antimuscarinics have been proposed as future pharmacotherapy for obstructive sleep apnea (OSA). However, the available randomized controlled trials (RCTs) showed heterogeneous results regarding the safety and efficacy of the combined regimen in OSA. Therefore, we performed this meta-analysis from the published RCTs to clarify this conflicting evidence.

METHODS

A systematic search of four electronic databases was done till December 2023.

RESULTS

Thirteen RCTs (n = 345) were systematically reviewed and meta-analyzed. The combined regimen significantly reduced apnea-hypopnea index (AHI): AHI 3% [events/h; Mean difference (MD): - 6.30; 95% Confidence interval (CI) (- 9.74, - 2.87); P = 0.0003], AHI 4% [events/h; MD: - 6.50; 95% CI (- 8.74, - 4.26 events/h); P < 0.00001]. All gasometric measures significantly improved in the combined regimen group except mean SpO2. No difference was found in total sleep time between the treatment and placebo. However, compared to placebo, the combined regimen altered sleep architecture and decreased sleep efficiency. Regarding OSA endotypes, the combined regimen significantly improved loop gain, pharyngeal muscle compensation, pharyngeal muscle recruitment, and respiratory arousal threshold.

CONCLUSION

The combined regimen effectively reduces AHI and OSA severity with improvement in almost all OSA endotypes. However, this regimen decreased sleep efficiency and altered sleep architecture. Short-term side effects can be confined to increased heart rate, dry mouth and urinary hesitancy. Therefore, noradrenergics and anti-muscarinics is a promising regimen for treating OSA, yet this optimism must be titrated by the lack of long-term effects of the regimen. Future RCTs with focus on the long-term efficacy of the regimen and cardiovascular outcomes is recommended.

Chinese consensus report on the assessment and management of obstructive sleep apnea in patients with cardiovascular disease: 2024 edition

As cardiovascular disease (CVD) incidence and mortality rates continue to rise in China, the importance of identifying and managing CVD risk factors grows. Obstructive sleep apnea (OSA) is a prevalent sleep-related breathing disorder, affecting an estimated 936 million individuals aged 30-69 worldwide, with China leading globally with about 176 million affected. Increasing research indicates a close association between OSA and the onset and progression of various CVD, significantly affecting outcomes. However, OSA has long been underrecognized and undertreated in CVD clinical practice. To address this gap, a multidisciplinary expert panel developed evidence-based recommendations using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology and the Delphi process. This consensus provides 17 recommendations on core clinical issues such as screening, diagnosis, treatment, and follow-up of CVD patients with OSA, aiming to standardize care and improve patient outcomes. The recommendations were informed by current evidence-based research and extensive expert consensus discussions. This approach seeks to support clinical decision-making, improve the quality of care, and address the unique challenges of managing OSA in Chinese CVD patients.

Association of vertigo with adult obstructive sleep apnea: A systematic review and meta-analysis

BACKGROUND

Several studies have demonstrated a relationship between vertigo and obstructive sleep apnea (OSA) in adults. This review examined the association between vertigo and OSA and investigated the effects of OSA treatment on vestibular function.

METHODS

Searches were conducted in PubMed, MEDLINE, EMBASE, Cochrane, Scopus, and Web of Science databases. Two authors independently searched the databases up to November 2023. Meta-analysis of caloric test, cervical vestibular evoked myogenic potential (cVEMP), and ocular vestibular evoked myogenic potential (oVEMP), between adults with and without OSA was done.

RESULTS

Overall, 28 studies were identified, and most of which focused on vestibular dysfunction in the OSA group. Compared with controls, adults with OSA had an increased risk of abnormal caloric test results (odds ratio [OR] = 4.8), absence of cVEMP (OR = 7.9), absence of oVEMP (OR = 6.2), decreased n1p2 amplitude (standardized mean difference [SMD] = -0.78), decreased p1n1 amplitude (SMD = -0.92), decreased p1n1 interval (SMD = -2.37) in cVEMP testing and prolonged n1 latency (SMD = 0.81) and decreased p1n1 amplitude (SMD = -0.51) in oVEMP testing. Three population-based studies implied a high risk of vertigo in adult OSA, although not statistically significant (OR = 2.53, 95 % confidence interval = 0.97 to 6.61). According to 3 studies, OSA is relatively prevalent among patients with vertigo. Another 3 studies regarding OSA treatment on vestibular functions revealed inconsistent findings.

CONCLUSION

Adults with OSA exhibit abnormalities in caloric, cVEMP, and oVEMP test results, indicating impairments in the semicircular canal, saccule, and utricle.

Obstructive sleep apnea syndrome (OSAS) in women: A forgotten cardiovascular risk factor

Sleep-disordered breathing is a highly prevalent disorder with negative impact on healthcare systems worldwide. This condition has detrimental effects on cardiovascular health and quality of life, and is frequently associated with a variety of comorbidities, including cardiovascular disease, heart failure, diabetes and atrial fibrillation. Nevertheless, it remains frequently undiagnosed and undertreated, especially in specific populations. Studies on sleep-disordered breathing have been conducted mainly on male patients, and the prevalence and severity of this disorder in women are underestimated. Recently, some clinical and laboratory evidence has highlighted the epidemiological and pathophysiological differences between men and women with sleep-disordered breathing. In this review, we discuss sex-related mechanisms of sleep-disordered breathing in frequently associated disorders, to improve clinical understanding of this condition and to simplify the practical application of targeted interventions. The aim is to improve prognosis among female patients and guarantee a better quality of life and a reduction in healthcare costs.

The impact of comprehensive healthy lifestyles on obstructive sleep apnea and the mediating role of BMI: insights from NHANES 2005-2008 and 2015-2018

OBJECTIVE

In this study, the associations between healthy lifestyles and obstructive sleep apnea (OSA) in middle-aged and elderly adults were investigated via data from the National Health and Nutrition Examination Survey (NHANES) for the periods of 2005-2008 and 2015-2018.

METHODS

A total of 6,406 participants aged 40 years and older were included in the analysis. Healthy lifestyle behaviors were assessed through diet quality, physical activity, sleep duration, alcohol consumption, smoking status, and body mass index (BMI). A composite healthy lifestyle score (ranging from 0 to 6) was created and categorized into insufficient (0-2), intermediate (3-4), and optimal (5-6) health groups. Weighted logistic regression models were used to examine the association between these lifestyle scores and OSA, adjusting for some demographic, socioeconomic, and clinical covariates. Additionally, mediation analysis was conducted to evaluate the role of BMI as a mediator in the relationship between the composite healthy lifestyle score and OSA, determining the proportion of the total effect mediated by BMI.

RESULTS

Participants were classified into insufficient (17.81%), intermediate (56.82%), and optimal (25.37%) lifestyle groups. Higher dietary quality (OR: 0.81, 95% CI: 0.66-0.99) and adequate weight (OR: 0.09, 95% CI: 0.07-0.11) were statistically associated with reduced OSA odds after adjustments, whereas the variables were not. Each one-point increase in the healthy lifestyle score was linked to a 33% reduction in OSA odds (OR: 0.67, 95% CI: 0.63-0.71). A significant linear trend was observed, with better adherence to healthy lifestyle correlating with lower odds of OSA (p for trend < 0.001). Compared with insufficient lifestyle, intermediate lifestyle was linked to a 27% reduction in OSA (OR: 0.73, 95% CI: 0.58-0.91), whereas optimal lifestyle was associated with a 74% reduction (OR: 0.26, 95% CI: 0.21-0.33). Mediation analysis revealed that BMI significantly mediated the relationship between healthy lifestyle score and OSA, accounting for approximately 59.2% of the total effect (P < 0.001). The direct effect of the healthy lifestyle score on OSA remained significant even when controlling for BMI (P < 0.001). Subgroup analyses confirmed consistent benefits across different demographic groups.

CONCLUSIONS

This study revealed that adherence to healthy lifestyles significantly reduces the odds of OSA, with optimal lifestyles leading to a marked decrease in the odds of OSA. Notably, BMI plays a critical mediating role in this relationship. These findings emphasize the importance of promoting healthy lifestyle interventions as a key strategy for the prevention and management of OSA.

An Artificial Intelligence-Based Non-Invasive Approach for Cardiovascular Disease Risk Stratification in Obstructive Sleep Apnea Patients: A Narrative Review

Background

Obstructive sleep apnea (OSA) is a severe condition associated with numerous cardiovascular complications, including heart failure. The complex biological and morphological relationship between OSA and atherosclerotic cardiovascular disease (ASCVD) poses challenges in predicting adverse cardiovascular outcomes. While artificial intelligence (AI) has shown potential for predicting cardiovascular disease (CVD) and stroke risks in other conditions, there is a lack of detailed, bias-free, and compressed AI models for ASCVD and stroke risk stratification in OSA patients. This study aimed to address this gap by proposing three hypotheses: (i) a strong relationship exists between OSA and ASCVD/stroke, (ii) deep learning (DL) can stratify ASCVD/stroke risk in OSA patients using surrogate carotid imaging, and (iii) including OSA risk as a covariate with cardiovascular risk factors can improve CVD risk stratification.

Methods

The study employed the Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) search strategy, yielding 191 studies that link OSA with coronary, carotid, and aortic atherosclerotic vascular diseases. This research investigated the link between OSA and CVD, explored DL solutions for OSA detection, and examined the role of DL in utilizing carotid surrogate biomarkers by saving costs. Lastly, we benchmark our strategy against previous studies.

Results

(i) This study found that CVD and OSA are indirectly or directly related. (ii) DL models demonstrated significant potential in improving OSA detection and proved effective in CVD risk stratification using carotid ultrasound as a biomarker. (iii) Additionally, DL was shown to be useful for CVD risk stratification in OSA patients; (iv) There are important AI attributes such as AI-bias, AI-explainability, AI-pruning, and AI-cloud, which play an important role in CVD risk for OSA patients.

Conclusions

DL provides a powerful tool for CVD risk stratification in OSA patients. These results can promote several recommendations for developing unique, bias-free, and explainable AI algorithms for predicting ASCVD and stroke risks in patients with OSA.

Study on OSA screening and influencing factors in community-based elderly hypertensive patients based on single-lead wearable ECG devices

PURPOSE

Assessing whether single-lead ECG can be effectively and relatively inexpensively used in large-scale OSA screening, and identifying factors influencing moderate-to-severe OSA among elderly hypertensive patients without atypical symptoms in primary care.

METHODS

The study gathered data from 15 medical institutions in Ningxia between January and December 2022 using cloud platforms. The dataset included basic information and 72-h ECG monitoring for 2573 hypertensive patients over 65. OSA screening was conducted using the single-lead wearable ECG devices based on the ACAT algorithm. A multivariable logistic regression identified the main factors affecting OSA severity in these patients, and the AUC was used to assess the model's predictive accuracy.

RESULTS

The study found an OSA detection rate of 87.10%, with 55.42% being moderate to severe cases. Key risk factors associated with developing moderate-to-severe OSA included cardiac irregularities like supraventricular extrasystole and atrioventricular block, male gender, lifestyle factors like alcohol consumption and smoking, and health indicators such as SDNN ≤ 100 ms, abnormal LF/HF ratio, BMI, and age. The model's accuracy for predicting OSA, indicated by a ROAUC of 0.625, was moderate. Factors like gender, tea consumption, stroke history, and ventricular tachycardia were also independently linked to OSA severity.

CONCLUSION

This study combines single-lead wearable ECG devices with the ACAT algorithm for OSA screening in Ningxia, China. Initial screening identified 87.10% of participants as having OSA, with 55.42% being moderate to severe cases. This suggests a convenient, low-cost, and repeatable ECG-based method for OSA screening, potentially improving early detection and management of OSA by identifying potential risk factors.

Long Term Cardiovascular Outcomes Between Sleep Surgery and Continuous Positive Airway Pressure

OBJECTIVES

Individuals with obstructive sleep apnea (OSA) suffer from a multitude of concurrent morbidities including cardiovascular disease (CVD). Limited data exists comparing long term cardiovascular disease (CVD) clinical outcomes for patients treated with surgical intervention versus continuous positive airway pressure (CPAP). The purpose of this study was to compare CVD outcomes at multiple time points comparing those treated with sleep surgery versus CPAP alone.

METHODS

A research database was used to assess outcomes: death, myocardial infarction, atrial fibrillation, heart failure, essential hypertension, and pulmonary hypertension at 5, 8, and 20 years for patients with OSA treated with surgical interventions (upper airway stimulation [UAS], uvulopalatopharyngoplasty [UPPP], and tonsillectomy) or CPAP alone. Subjects were identified using ICD and CPT codes and analyses were conducted with and without propensity score matching for age, sex, race, BMI, myocardial infarction (MI), essential hypertension, pulmonary hypertension, atrial fibrillation, and heart failure.

RESULTS

All surgical interventions demonstrated benefit over CPAP alone at most time points for most surgical interventions. At 8 years, for all sleep surgeries (UAS or UPPP or tonsillectomy) (n = 6627) versus treatment with CPAP alone (n = 6627), matched subjects demonstrated decreased risk (odds ratios) and superior survival (hazard ratios and log ranks tests) for death (OR = 0.49 [0.39, 0.62] P ≤ .0001, HR = 0.29 [0.23, 0.37], χ2 = 109.58 P ≤ .0001), myocardial infarction (OR = 0.67 [0.54, 0.84] P = .0005*, HR = 0.48 [0.38, 0.60], χ2 = 42.40 P ≤ .0001), atrial fibrillation (OR = 0.70 [0.59, 0.83] P ≤ .0001, HR = 0.54 [0.45, 0.64], χ2 = 51.53 P ≤ .0001), heart failure (OR = 0.55 [0.47, 0.64] P ≤ .0001, HR = 0.41 [0.35, 0.47], χ2 = 137.416 P ≤ .0001), essential hypertension (OR = 0.88 [0.82, 0.94] P = .0002, HR = 0.78 [0.74, 0.82], χ2 = 76.38 P ≤ .0001), and pulmonary hypertension (OR = 0.51 [0.40, 0.65] P ≤ .0001, HR = 0.38 [0.29, 0.48], χ2 = 60.67 P ≤ .0001) where P ≤ .00037 indicated statistical significance*.

CONCLUSION

This investigation suggests surgical management of obstructive sleep apnea may contribute to the mitigation of long-term clinical CVD morbidity.

Evaluating the relationship between obstructive sleep apnea and all-cause and cause-specific mortality in adults with and without metabolic syndrome using real-world data

BACKGROUND AND AIM

Obstructive Sleep Apnea (OSA) is a prevalent sleep disorder linked to increased risks of cardiovascular and metabolic disorders, significantly raising overall mortality rates. This study explores the associations between OSA and mortality in adults with and without Metabolic Syndrome (MetS) using data from the National Health and Nutrition Examination Survey (NHANES).

METHODS AND RESULTS

Data from NHANES (2005-2008) were analyzed, including 11,759 participants. OSA and MetS were identified based on survey responses and standard clinical criteria. Cox proportional hazards regression models were used to assess the relationship between OSA and mortality, adjusting for covariates. OSA was associated with significantly higher all-cause and cardiovascular mortality in the general population. In individuals without MetS, OSA was linked to higher all-cause and cardiovascular mortality. However, in individuals with MetS, OSA did not significantly affect mortality rates after adjusting for covariates.

CONCLUSION

OSA increases the risk of all-cause and cardiovascular mortality in individuals without MetS, emphasizing the need for early identification and management, particularly in those without metabolic comorbidities. In contrast, the impact of OSA on mortality in individuals with MetS may be mitigated by medical monitoring and treatment. These findings highlight the importance of individualized clinical strategies and call for further research to explore the underlying mechanisms of OSA-MetS interactions.

Gut Microbiota and Derived Metabolites Mediate Obstructive Sleep Apnea Induced Atherosclerosis

Background

Obstructive sleep apnea (OSA) is characterized by intermittent hypoxia/hypercapnia (IHC), affects predominantly obese individuals, and increases atherosclerosis risk. Since we and others have implicated gut microbiota and metabolites in atherogenesis, we dissected their contributions to OSA-induced atherosclerosis.

Results

Atherosclerotic lesions were compared between conventionally-reared specific pathogen free (SPF) and germ-free (GF) ApoE -/- mice following a high fat high cholesterol diet (HFHC), with and without IHC conditions. The fecal microbiota and metabolome were profiled using 16S rRNA gene amplicon sequencing and untargeted tandem mass spectrometry (LC-MS/MS) respectively. Phenotypic data showed that HFHC significantly increased atherosclerosis as compared to regular chow (RC) in both aorta and pulmonary artery (PA) of SPF mice. IHC exacerbated lesions in addition to HFHC. Differential abundance analysis of gut microbiota identified an enrichment of Akkermansiaceae and a depletion of Muribaculaceae (formerly S24-7) family members in the HFHC-IHC group. LC-MS/MS showed a dysregulation of bile acid profiles with taurocholic acid, taurodeoxycholic acid, and 12-ketodeoxycholic acid enriched in the HFHC-IHC group, long-chain N-acyl amides, and phosphatidylcholines. Interestingly, GF ApoE -/- mice markedly reduced atherosclerotic formation relative to SPF ApoE -/- mice in the aorta under HFHC/IHC conditions. In contrast, microbial colonization did not show a significant impact on the atherosclerotic progression in PA.

Conclusions

In summary, this research demonstrated that (1) IHC acts cooperatively with HFHC to induce atherosclerosis; (2) gut microbiota modulate atherogenesis, induced by HFHC/IHC, in the aorta not in PA; (3) different analytical methods suggest that a specific imbalance between Akkermansiaceae and Muribaculaceae bacterial families mediate OSA-induced atherosclerosis; and (4) derived bile acids, such as deoxycholic acid and lithocholic acid, regulate atherosclerosis in OSA. The knowledge obtained provides novel insights into the potential therapeutic approaches to prevent and treat OSA-induced atherosclerosis.

Effects of Continuous Positive Airway Pressure Treatment on Vascular Function in a Real-Life Cohort of Elderly Patients with Obstructive Sleep Apnoea Syndrome

BACKGROUND

Obstructive sleep apnoea syndrome (OSAS) is an independent risk factor for cardiovascular morbidity and mortality and has a detrimental effect on vascular function, in particular on arterial stiffness and endothelial function. Continuous positive airway pressure (CPAP) is the gold-standard therapy for OSAS and its effects on arterial stiffness and endothelial function have been demonstrated in non-elderly patients.

OBJECTIVES

The objective of this study was to evaluate the effect of one year of CPAP treatment on arterial stiffness, through assessment of carotid-femoral pulse wave velocity (cf-PWV), and on endothelial function, through the reactive hyperaemia index (RHi), in a real-life cohort of elderly patients with moderate-to-severe OSAS and several comorbidities.

METHODS

In this nonrandomised prospective study, we enrolled 469 consecutive elderly patients affected by moderate-to-severe OSAS distributed in two groups: CPAP-treated (n = 225) and untreated patients (n = 244).

RESULTS

At one-year follow-up, in the treated group emerged an important improvement in poligraphics (AHI, ODI, TC90, mean SpO2%), laboratory (HOMA index, eGFR, hs-CRP) and vascular function parameters: cf-PWV. The stepwise multivariate linear regression demonstrated a significant correlation between the delta of the polygraph parameters and the delta of PWV and RHi.

CONCLUSIONS

Our study confirmed the favourable effects of CPAP therapy in a cohort of elderly patients affected by OSAS and several comorbidities on sleep respiratory parameters and vascular function; early diagnosis and treatment with CPAP might be beneficial to delay or prevent the occurrence of cardiovascular events in these groups of patients.

Sustained hypoxia but not intermittent hypoxia induces HIF-1α transcriptional response in human aortic endothelial cells

Obstructive sleep apnea (OSA) is characterized by intermittent hypoxic environments at the cellular level and is an independent risk factor for the development of cardiovascular disease. Endothelial cell (EC) dysfunction precedes the development of cardiovascular disease; however, the mechanisms by which ECs respond to these intermittent hypoxic events are poorly understood. To better understand EC responses to hypoxia, we examined the effects of sustained hypoxia (SH) and intermittent hypoxia (IH) on the activation of HIF-1α in ECs. While SH stabilized HIF-1α and led to its nuclear localization, IH did not activate HIF-1α and the expression of its target genes. Using RNA-sequencing, we evaluated transcriptional responses of ECs to hypoxia. SH induced the expression of HIF-1α and hypoxia response genes, while IH affected cell-cycle regulation genes. A cytoscape protein-protein interaction network for EC response to hypoxia was created with differentially expressed genes. The network comprises cell-cycle regulation, inflammatory signaling via NF-κB and response to VEGF stimulus subnetworks on which SH and IH had distinct activities. As OSA is associated with elevated catecholamines, we investigated the effect of epinephrine on the EC response to SH and IH. Transcriptomic responses under IH and epinephrine revealed protein-protein interaction networks emphasizing distinct subnetworks, including cytokine-mediated TNFα signaling via NF-κB, Wnt/LRP/DKK signaling and cell cycle regulation. This study reveals differential transcriptomic responses under SH and IH characterised by HIF-1α transcriptional response induced only by SH, but not by IH. The study also features the potential molecular events that may occur at the vascular level in OSA.

Roles of social support and strain in predicting older adults' sleep disturbances

Sleep disturbances impact the well-being of older adults, but there has been limited research on their longitudinal patterns and how they are affected by the quality of social relationships. This study explored longitudinal sleep disturbance patterns and examined the influence of social support and social strain on sleep disturbances in older adults using data from the Health and Retirement Study (HRS) spanning from 2010 to 2018. Group-based trajectory modeling identified distinct trajectory groups. Multinomial logistic regression and a fixed effects model investigated the relationship between sleep disturbances, social support, social strain, and sociodemographic factors. Three sleep disturbance trajectories were identified: high sleep disturbances, moderate sleep disturbances, and low sleep disturbances. Multinomial logistic regression showed that higher social support decreased the likelihood of classification in the high and moderate sleep disturbance groups. Conversely, higher social strain scores increased the likelihood of belonging to the high and moderate sleep disturbance groups. The fixed effects model confirmed the role of social support in predicting sleep disturbances over time, but social strain was not a significant predictor. These findings suggest the need for tailored interventions addressing social support to reduce sleep disturbances in this population.

Predictors and Prevalence of Severe Obstructive Sleep Apnea: A Cross-Sectional Study in Erbil, Kurdistan Region, Iraq

Background Obstructive sleep apnea (OSA) is a common sleep disorder that's characterized by episodes of a complete or partial collapse of the upper airway with an associated decrease in oxygen saturation or arousal from sleep. According to the American Academy of Sleep Medicine (AASM), OSA is categorized based on polysomnography findings into mild, moderate, and severe. Objectives This study aims at determining the prevalence of the severities of OSA in Erbil, Kurdistan Region of Iraq, as well as discovering the predictors for severe OSA. Methods This was a cross-sectional study that was carried out from December 2021 to July 2023 on patients displaying OSA symptoms in a sleep study section of a private clinic in Erbil, Kurdistan Region of Iraq. A detailed questionnaire was designed to collect the data, and IBM SPSS Statistics for Windows, Version 26 (Released 2019; IBM Corp., Armonk, New York, United States) was used to analyze it. The polysomnography device used for the diagnosis of OSA was a Philips Respironics Alice NightOne home device, and Philips Respironics Sleepware G3 (Koninklijke Philips N.V., Amsterdam, Netherlands) was used to analyze the sleep data. Results A sample size of 328 OSA cases was analyzed. The results revealed a prevalence of 47% (155) for severe OSA. Apnea-hypopnea index (AHI) was negatively correlated with lowest and average oxygen saturation, while it was positively correlated with time spent with oxygen saturation under 89%, body mass index (BMI), and weight of the participants. Furthermore, stepwise multiple regression tests revealed BMI, age, gender, and heart failure as independent predictors for AHI. Conclusion This study highlights the links between OSA and various chronic health conditions. Furthermore, it underscores the importance of factors like age, obesity, and gender in influencing OSA severity. The identification of predictors for OSA severity can assist in risk assessment and personalized interventions.

Gender Modulated the Association of Sleep Apnea and Sleep Duration with Arterial Stiffness: The ELSA-Brasil Study

Increased arterial stiffness is independently associated with cardiovascular risk. Obstructive sleep apnea (OSA) and sleep duration (SDUR) may contribute to increased arterial stiffness, but it is unclear whether this association is modulated by gender. We aimed to evaluate the potential impact of gender in modulating the association of OSA and SDUR with arterial stiffness. Participants from the ELSA-Brasil study performed sleep assessments with portable polygraph to define OSA severity and SDUR by 1-week wrist actigraphy. Pulse wave velocity (PWV) was measured using a standard technique without access to the sleep data. We studied 1863 participants (42.2% male, age: 49±8 years, respiratory disturbance index (RDI): 9.9 (4.5-19.4) events/h, SDUR: 6.5 (5.9-7.1) hours, mean PWV: 7.3 ± 1.2 m/s). We found that men had higher PWV, higher frequency of diabetes, and higher blood pressure when compared to women. The regression analysis showed an independent association between increased RDI and PWV in men (ß: 0.007; 95% CI: 0.001-0.012), but not in women. In contrast, an independent association between SDUR and increased arterial stiffness was observed only in women (ß: 0.068; 95% CI: 0.002-0.134). In conclusion, the association of sleep disorders with arterial stiffness showed a distinct gender pattern depending on the sleep variable studied.

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.

Outcomes and Predictors of Success Following Multilevel Surgery in Positional and Nonpositional Obstructive Sleep Apnea

OBJECTIVE

To assess the surgical outcomes and identify predictors of surgical success in patients with positional and non-positional obstructive sleep apnea following multilevel airway surgery.

STUDY DESIGN

Retrospective cohort study.

SETTING

Singe-tertiary medical center.

METHODS

This study included 158 patients with obstructive sleep apnea who underwent multilevel airway surgery. Patients were divided into 2 groups according to position dependency: "positional patients" group (n = 100), and "nonpositional patients" group (n = 58). The characteristics and surgical outcomes of the 2 groups were compared.

RESULTS

The nonpositional group included younger and more obese patients in comparison to the positional group. Moreover, the nonpositional group had more severe disease than the positional group. Both groups showed overall improvement after surgery, and the surgical success rate did not differ significantly between the 2 groups (nonpositional, 41.4% vs positional, 48.0%; P = .424). Notably, 69.0% of patients belonging to the non-positional group converted to positional group postoperatively. Logistic regression analysis revealed that larger tonsil size, female sex, and higher mean O2 saturation were associated with higher success rate in the positional group, whereas larger tonsil size was associated with surgical success in the nonpositional group.

CONCLUSION

Both nonpositional and positional groups showed improvements following multilevel airway surgery, and surgery induced a transition from nonpositional to positional group. Given that the factors related to surgical success differed between the two groups, surgeons should consider position dependency and these distinct factors during decision-making.

"Skeletal surgical approach in Down Syndrome with Obstructive Sleep Apnea."

Failing to address Obstructive Sleep Apnea (OSA) in Down Syndrome (DS) patients can have serious consequences, leading to increased mortality. Moreover, a notable portion of individuals find it challenging to tolerate Continuous Positive Airway Pressure (CPAP). Therefore, this study aims to share our experiences in treating adult DS patients with moderate to severe OSA who don't tolerate CPAP using various surgical approaches. A retrospective analytical study including 20 DS with moderate to severe/very severe OSA who had no tolerance to Continuous Positive Airway Pressure (CPAP) was conducted. Regarding the individual skeletal characteristics of each patient various orthognathic surgery techniques were performed. Two in-hospital polysomnographies (PSG) were undertaken for every patient; one before the surgical procedure, while another was performed between 6 and 60 months of the follow-up post-surgery period. Polysomnographic variables were analyzed in this study such as AHI, ODI, and T90, which all showed statistically significant improvement after surgery with a p value in the Wilcoxon test <0,01. These results have remained stable over time, with no recurrences of OSA observed over the five years of follow-up. Thus, orthognathic surgery may be the only viable option for individuals with DS who are unable to tolerate CPAP.

Obstructive Sleep Apnea and Cardiovascular Diseases: A Systematic Review and Meta-Analysis of Prospective Studies

Obstructive sleep apnea (OSA) is a prevalent clinical disorder characterized by intermittent airway obstruction during sleep, resulting in hypoxemia and hypercapnia. Although OSA is associated with increased cardiovascular disease (CVD) risk, such as hypertension, the precise nature of this relationship remains uncertain. This systematic review and meta-analysis aim to evaluate the potential links between OSA and cardiovascular outcomes by synthesizing data from recent prospective studies. A systematic literature search was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, utilizing electronic databases, including PubMed/MEDLINE, Scopus, and the Cochrane Library. The PICTS (patients, index test, comparator/reference test, target condition, study design) framework was used to structure the primary research question and define the investigation's scope. The Newcastle-Ottawa Scale (NOS) was employed for quality appraisal, and a meta-analysis was performed using Review Manager 5.4 software (Cochrane Collaboration, London, UK). The analysis included 12 studies, focusing on the association between OSA and various cardiovascular outcomes, including hypertension, coronary artery disease, congestive heart failure, cardiac arrhythmias, and cardiovascular events. The pooled relative risk (RR) from the random-effects model was 0.79 (95% CI: 0.56-1.03), indicating a non-significant reduction in cardiovascular risk associated with OSA. The results were heterogeneous, with individual studies showing both increased and decreased risk. Subgroup analyses based on study design, patient characteristics, and follow-up duration suggested that the observed associations were stable across different subsets of studies. However, the overall findings did not establish a definitive causal link between OSA and increased cardiovascular risk. This meta-analysis underscores the complex relationship between OSA and CVD, highlighting the need for further research to elucidate the underlying mechanisms and confirm the potential causal association. Despite the lack of significant findings, the high prevalence of OSA and its association with cardiovascular risk factors warrant routine screening and early intervention, particularly through continuous positive airway pressure (CPAP) therapy, which may mitigate the cardiovascular risks linked to OSA. Future studies should focus on high-quality prospective data and explore the impact of OSA management on cardiovascular outcomes.

Predictors of sleepiness in a large-scale epidemiology study ESSE-RF

Introduction

To identify predictors of excessive daytime sleepiness we analyzed data from the 'Epidemiology of cardiovascular diseases in regions of Russia (ESSE-RF)' study.

Methods

Data from participants of the cohort study ESSE-RF (2012-2013), aged 25-64 years, from 13 regions of Russia were analyzed (2012-2013). The participants were interviewed regarding their sleep complaints, including difficulties with initiating and maintaining sleep, sleepiness, and use of sleeping pills. Sleepiness was considered significant if it occurred at least three times a week. The examination encompassed social, demographic, and anthropometric measures, lifestyle factors, self-reported diseases, and laboratory parameters. The final analysis included 13,255 respondents.

Results

Frequent (≥3 times/week) sleepiness was reported by 5,8%, and occasional sleepiness (1-2 times/week) by 10.8% of respondents. Multivariate regression analysis identified significant predictors of frequent sleepiness. Sleep complaints (insomnia, sleep apnea, snoring) and frequent use of sleep medication were prominent factors. Additionally, age, female gender, higher education, and retirement status were associated with sleepiness. Beyond demographics and sleep, the analysis revealed predictors: abnormal anxiety levels, low high-density lipoprotein, high salt intake and following medical conditions: arrhythmia, hypertension, myocardial infarction, other heart diseases, and renal disease.

Conclusion

This study identified a significant prevalence of EDS in Russians, aligning with global trends. However, findings suggest potential regional variations. Analysis revealed a complex interplay of factors contributing to EDS, highlighting the importance of individualized treatment approaches for improved sleep health.

Obstructive Sleep Apnea, Platelet Aggregation, and Cardiovascular Risk

BACKGROUND

Although related, the precise mechanisms linking obstructive sleep apnea (OSA) and cardiovascular disease (CVD) are unclear. Platelets are mediators of CVD risk and thrombosis and prior studies suggested associations of OSA and platelet activity. The aim of this study is to assess the link between OSA, platelet activity, and CVD-related risk factors.

METHODS AND RESULTS

We studied the association of OSA-measures and platelet aggregation in participants dually enrolled in the SHHS (Sleep Heart and Health Study) and FHS (Framingham Heart Study). We applied linear regression models with adjustment for demographic and clinical covariates and explored interactions with OSA and CVD-related factors, including age, sex, body mass index, hypertension, OSA diagnosis (apnea-hypopnea index 4%≥5), and aspirin use. Our final sample was of 482 participants (60 years [14.00], 50.4% female). No associations were observed between apnea-hypopnea index 4% and platelet aggregation in the main sample. Stratified analysis revealed an association in aspirin users (n=65) for our primary exposure (apnea-hypopnea index 4%, β=0.523; P<0.001; n=65), and secondary exposures: hypoxic burden (β=0.358; P<0.001), minimum saturation (β=-0.519; P=0.026), and oxygen desaturation index 3% (β=74.672; P=0.002). No associations were detected in nonaspirin users (n=417).

CONCLUSIONS

No associations were detected between OSA and platelet aggregation in a community sample. Our finding that OSA associates with increased platelet aggregation in the aspirin group, most of whom use it for primary prevention of CVD, suggests that platelet aggregation may mediate the adverse impact of OSA on vascular health in individuals with existing CVD risk, supporting further investigation.

Obesity: the perfect storm for heart failure

Obesity condition causes morphological and functional alterations involving the cardiovascular system. These can represent the substrates for different cardiovascular diseases, such as atrial fibrillation, coronary artery disease, sudden cardiac death, and heart failure (HF) with both preserved ejection fraction (EF) and reduced EF. Different pathogenetic mechanisms may help to explain the association between obesity and HF including left ventricular remodelling and epicardial fat accumulation, endothelial dysfunction, and coronary microvascular dysfunction. Multi-imaging modalities are required for appropriate recognition of subclinical systolic dysfunction typically associated with obesity, with echocardiography being the most cost-effective technique. Therapeutic approach in patients with obesity and HF is challenging, particularly regarding patients with preserved EF in which few strategies with high level of evidence are available. Weight loss is of extreme importance in patients with obesity and HF, being a primary therapeutic intervention. Sodium-glucose co-transporter-2 inhibitors have been recently introduced as a novel tool in the management of HF patients. The present review aims at analysing the most recent studies supporting pathogenesis, diagnosis, and management in patients with obesity and HF.

Association Between Soft Tissue Measures From Computed Tomography and Upper Airway Collapsibility on Drug-Induced Sleep Endoscopy

OBJECTIVE

Positive airway pressure (PAP) titration during drug-induced sleep endoscopy (DISE) provides objective measures of upper airway collapsibility. While skeletal measurements relate to collapsibility measures on DISE, the influence of soft tissue dimensions on upper airway collapsibility is not known. We analyzed the relationship of measures of upper airway soft tissue volumes, specifically soft palate, pharyngeal lateral walls, and tongue, with metrics of collapsibility.

STUDY DESIGN

Cross-sectional analysis from a prospective cohort.

SETTING

Academic medical center.

METHODS

Patients seeking PAP alternative therapies for obstructive sleep apnea (OSA) underwent standardized supine computed tomography (CT) acquisition and DISE protocols. The CT analysis primarily focused on soft tissue volumes and, secondarily, on airway and skeletal volumetric measures. DISE with PAP administration (DISE-PAP) enabled the determination of the pressure at which inspiratory airflow first commenced (pharyngeal critical pressure, PcritA) and the pressure at which inspiratory flow limitation was abolished (pharyngeal opening pressure, PhOP). Both unadjusted and adjusted correlation analyses were performed to understand the relationship between upper airway anatomy and either PcritA or PhOP.

RESULTS

One hundred thirty-nine subjects completed both CT and DISE-PAP. On average, patients were male (70.5%), white (84.2%), middle-aged (56.6 ± 13.5 years), and overweight (29.6 ± 4.7 kg/m2), with moderate-severe apnea-hypopnea index (29.7 ± 21.3 events/h). Adjusted for age, sex, body mass index, and skeletal volumes, soft palate, and lateral pharyngeal wall volumes were not associated with PhOP or PcritA, but a larger tongue was associated with more positive PhOP (⍴ = 0.20, P = .02), and more positive PcritA (⍴ = 0.16, P = .07). Exploratory analyses revealed smaller minimum cross-sectional retropalatal area and intramandibular volume were also associated with increased collapsibility measures.

CONCLUSION

After controlling for clinical factors and skeletal volume, greater tongue volume was associated with more severe collapsibility during DISE. These results, in concert with previous work, suggest that greater tongue volume in a smaller skeletal dimensions contribute to the severity of airway collapsibility, a key driver of OSA pathogenesis.

OSApredictor: A tool for prediction of moderate to severe obstructive sleep apnea-hypopnea using readily available patient characteristics

Sleep apnea is a common sleep disorder. The availability of an easy-to-use sleep apnea predictor would provide a public health benefit by promoting early diagnosis and treatment. Our goal was to develop a prediction tool that used commonly available variables and was accessible to the public through a web site. Using data from polysomnography (PSG) studies that measured the apnea-hypopnea index (AHI), we built a machine learning tool to predict the presence of moderate to severe obstructive sleep apnea (OSA) (defined as AHI ≥15). Our tool employs only seven widely available predictor variables: age, sex, weight, height, pulse oxygen saturation, heart rate and respiratory rate. As a preliminary step, we used 16,958 PSG studies to examine eight machine learning algorithms via five-fold cross validation and determined that XGBoost exhibited superior predictive performance. We then refined the XGBoost predictor by randomly partitioning the data into a training and a test set (13,566 and 3392 PSGs, respectively) and repeatedly subsampling from the training set to construct 1000 training subsets. We evaluated each of the resulting 1000 XGBoost models on the single set-aside test set. The resulting classification tool correctly identified 72.5 % of those with moderate to severe OSA as having the condition (sensitivity) and 62.8 % of those without moderate to-severe OSA as not having it (specificity); overall accuracy was 66 %. We developed a user-friendly publicly available website (https://manticore.niehs.nih.gov/OSApredictor). We hope that our easy-to-use tool will serve as a screening vehicle that enables more patients to be clinically diagnosed and treated for OSA.

Exploring the bidirectional relationship between sleep disorders and atrial fibrillation: implications for risk stratification and management

BACKGROUND

Atrial fibrillation (AF) is characterized by the absence of p-waves on ECG and irregular rhythm. It often presents with palpitations either palpitations may occur acutely over a short period or intermittently over several years. Other cardinal symptoms of atrial fibrillation include fatigue, dyspnea, and lightheadedness; it is important however to note that most affected individuals are asymptomatic. Concurrently, sleep disorders such as obstructive sleep apnea (OSA), insomnia, narcolepsy, and circadian rhythm disorders which are a group of conditions associated with the body's internal clock that affect the timing of sleep and alertness, are raising concerns due to their potential associations to arrhythmias. This review explores the bidirectional relationship between AF and sleep disorders, highlighting their implications for risk stratification and management strategies.

MAIN BODY

The narrative approach of this review synthesizes evidence from numerous studies obtained through meticulous literature searches. Specific sleep disorders with a bidirectional relationship with AF are the focus, with scrutiny on the prevalence of this connection. The examination delves into the pathophysiology of sleep-related autonomic dysregulation and inflammation, emphasizing potential management modalities. Various meta-analysis cohorts have highlighted a strong connection between sleep disorders and atrial fibrillation (AF). Patients with sleep disorders, especially OSA, have a higher likelihood of developing AF, and conversely, those with AF are more prone to sleep disorders. This impact is not limited to development, as sleep disorders also contribute to the progression of AF, with AF, in turn, negatively impacting sleep duration and quality. Sleep disorders may play an important role in atrial remodeling as well as electrophysiological abnormalities, rendering the atrial tissue more susceptible to arrhythmogenesis. The narrative review suggests that treating sleep disorders could not only improve sleep quality but also reduce risk factors associated with atrial fibrillation. The effective management of sleep disorders emerges as a potential challenge in preventing and treating atrial fibrillation.

CONCLUSION

In conclusion, this narrative study highlights the bidirectional relationship between sleep disorders and atrial fibrillation. There is a positive correlation, affecting the development, progression, and management of atrial fibrillation. The detrimental impact of sleep disorders on atrial remodeling and electrophysiological abnormalities underscores the significance of their diagnosis and treatment. Education about the importance of sleep and the benefits of sleep disorder treatment becomes imperative for patients with AF and sleep disorders.

Obstructive sleep apnea and cardiovascular risk

Patients with obstructive sleep apnea (OSA) experience repetitive episodes of upper airway obstruction due to recurrent collapse during sleep. This leads to intermittent hypoxia episodes, which, through complex pathophysiological mechanisms, trigger sympathetic overactivation, endothelial dysfunction, hypercoagulation, and metabolic dysregulation. Consequently, other cardiovascular risk factors such as hypertension, metabolic syndrome, and diabetes are induced. Furthermore, this enhances target organ damage, affecting the heart, arteries, and kidneys, leading to an increased risk of cardiovascular morbidity and mortality. Among the various treatments for OSA, Continuous Positive Airway Pressure (CPAP) has been extensively studied. To date, this treatment has shown mild benefits in reducing blood pressure, particularly noticeable in patients with resistant hypertension. Furthermore, CPAP treatment appears to reduce cardiovascular events, both in primary and secondary prevention, though this benefit is limited to individuals with good compliance (CPAP use ≥4h/night). Future research perspectives in OSA seem to focus on identifying patients in whom the condition significantly influences cardiovascular risk, thus determining those who would benefit the most from treatment in the reduction of cardiovascular risk.

Evaluation of Serum/Plasma Levels of Interleukins (IL-6, IL-12, IL-17, IL-18, and IL-23) in Adults and Children with Obstructive Sleep Apnea: A Systematic Review, Meta-Analysis, and Trial Sequential Analysis

Obstructive sleep apnea (OSA) is a chronic inflammatory disease characterized by partial or complete upper airway obstruction during sleep. We aimed to evaluate serum/plasma levels of several cytokines (interleukin [IL]-6, IL-12, IL-17, IL-18, and IL-23) in a systematic review meta-analysis in both adults and children with OSA compared with controls. We conducted a comprehensive search of 4 digital databases (PubMed, Web of Science, Scopus, and Cochrane Library) up until October 19, 2023, without any limitations. For our meta-analysis, we used Review Manager, version 5.3, and displayed the data as the standardized mean difference (SMD) and 95% confidence interval (CI) to assess the correlation between cytokine levels and OSA. We utilized Comprehensive Meta-Analysis version 3.0 software to conduct bias analyses, meta-regression, and sensitivity analyses. From 1881 records, 84 articles were included in the systematic review and meta-analysis. In adults, the pooled SMDs for IL-6 level were 0.79 (P value < 0.00001), for IL-17 level were 0.74 (P value = 0.14), and for IL-18 level were 0.43 (P value = 0.00002). In children, the pooled SMD for IL-6 was 1.10 (P value < 0.00001), for IL-12 was 0.47 (P value = 0.10), for IL-17 was 2.21 (a P value = 0.24), for IL-18 was 0.19 (P value = 0.07), and for IL-23 was 2.46 (P value < 0.0001). The subgroup analysis showed that the ethnicity, mean body mass index, and mean apnea-hypopnea index for IL-6 levels in adults and the ethnicity for IL-6 levels in children were effective factors in the pooled SMD. The findings of the trial sequential analysis revealed that adequate evidence has been obtained. The analysis of IL levels in adults and children with OSA compared with those without OSA revealed significant differences. In adults, IL-6 and IL-18 levels were significantly higher in the OSA group, while in children, only IL-6 and IL-23 levels were significantly elevated.

Socioeconomic determinants of moderate and severe obstructive sleep apnea in children: A pre and post COVID analysis

INTRODUCTION

COVID-19 has disproportionately affected healthcare access of certain minority groups, and thus could contribute to delay in timely evaluation and management of pediatric obstructive sleep apnea (OSA). Socioeconomic status (SES) is known to affect healthcare access in pediatric otolaryngology and may also be a risk factor for OSA and its associated co-morbidities.

OBJECTIVES

Our primary objective is to determine the impact of COVID-19 on time to diagnosis (TTD) and time to treatment (TTT) of polysomnography (PSG)-proven moderate to severe pediatric OSA in different socioeconomic classes. Secondary objectives include determining the impact of racial and demographic factors on TTD and TTT.

METHODS

This is a retrospective chart review of 120 children; 60 children pre-COVID (February 2018 to February 2020), and 60 children post-COVID onset (March 2020 to March 2022). This study was performed at a pediatric teaching hospital and tertiary referral center, and involved children aged 3-17 years old with outpatient PSG-proven moderate to severe OSA. Approval was obtained from our hospital's institutional review board (IRB).

RESULTS

There were a total of 120 children, 60 in each group. The average age was 9.5 years old; females constituted 41.6 % of the sample. TTD increased from 53.7 days pre-covid to 103 days post-COVID onset in all children (p = 0.00), 42.5 days-151.9 days in white children (p = 0.00), 38 days-142.7 days in children with high SES (p = 0.00), 32.1 days-146.5 days in children with private insurance (p = 0.00), and 65.7 days-105.8 days in children with public insurance (p = 0.04). TTT did not change significantly.

CONCLUSION

Our results show that TTD of OSA and obesity in advantaged groups were affected to a greater degree than disadvantaged groups. This suggests children of all socioeconomic groups are susceptible to healthcare disparities and the COVID-19 pandemic has uncovered the vulnerability of such populations. Policymakers should consider providing more funding and support for all children, including continued funding for those with lower SES.

Sleep apnoea, gut dysbiosis and cognitive dysfunction

Sleep disorders are becoming increasingly common, and their distinct effects on physical and mental health require elaborate investigation. Gut dysbiosis (GD) has been reported in sleep-related disorders, but sleep apnoea is of particular significance because of its higher prevalence and chronicity. Cumulative evidence has suggested a link between sleep apnoea and GD. This review highlights the gut-brain communication axis that is mediated via commensal microbes and various microbiota-derived metabolites (e.g. short-chain fatty acids, lipopolysaccharide and trimethyl amine N-oxide), neurotransmitters (e.g. γ-aminobutyric acid, serotonin, glutamate and dopamine), immune cells and inflammatory mediators, as well as the vagus nerve and hypothalamic-pituitary-adrenal axis. This review also discusses the pathological role underpinning GD and altered gut bacterial populations in sleep apnoea and its related comorbid conditions, particularly cognitive dysfunction. In addition, the review examines the preclinical and clinical evidence, which suggests that prebiotics and probiotics may potentially be beneficial in sleep apnoea and its comorbidities through restoration of eubiosis or gut microbial homeostasis that regulates neural, metabolic and immune responses, as well as physiological barrier integrity via the gut-brain axis.

The signaling pathways in obesity-related complications

Obesity, a rapidly expanding epidemic worldwide, is known to exacerbate many medical conditions, making it a significant factor in multiple diseases and their associated complications. This threatening epidemic is linked to various harmful conditions such as type 2 diabetes mellitus, hypertension, metabolic dysfunction-associated steatotic liver disease, polycystic ovary syndrome, cardiovascular diseases (CVDs), dyslipidemia, and cancer. The rise in urbanization and sedentary lifestyles creates an environment that fosters obesity, leading to both psychosocial and medical complications. To identify individuals at risk and ensure timely treatment, it is crucial to have a better understanding of the pathophysiology of obesity and its comorbidities. This comprehensive review highlights the relationship between obesity and obesity-associated complications, including type 2 diabetes, hypertension, (CVDs), dyslipidemia, polycystic ovary syndrome, metabolic dysfunction-associated steatotic liver disease, gastrointestinal complications, and obstructive sleep apnea. It also explores the potential mechanisms underlying these associations. A thorough analysis of the interplay between obesity and its associated complications is vital in developing effective therapeutic strategies to combat the exponential increase in global obesity rates and mitigate the deadly consequences of this polygenic condition.

Role of NF-κB in cardiac changes of obstructive sleep apnoea rabbits treated by mandibular advancement device

BACKGROUND

Obstructive sleep apnoea (OSA) is an independent risk factor for cardiovascular diseases. We aimed to investigate the role of nuclear factor-kappa B (NF-κB) in the changes of cardiac structures in OSA rabbits treated by mandibular advancement device (MAD).

METHODS

Eighteen male New Zealand white rabbits aged 6 months were randomly divided into three groups: control group, group OSA and group MAD. Hyaluronate gel was injected into the soft palate of the rabbits in group OSA and group MAD to induce OSA. The cone beam computer tomography (CBCT) of the upper airway and polysomnography (PSG) was performed to ensure successful modelling. CBCT and PSG were applied again to detect the effects of MAD treatment. All animals were induced to sleep in a supine position for 4-6 h a day for 8 weeks. Then the levels of NF-κB, Interleukin 6 (IL-6), Interleukin 10 (IL-10) and the proportion of myocardial fibrosis (MF) were detected.

RESULTS

The higher activation of NF-κB, IL-6 and IL-10 were found in the OSA group than in the control group, leading to the increase of collagen fibres compared with the control group. Furthermore, the apnoea-hypopnea index (AHI) was positively correlated with the above factors. There were no significant differences between group MAD and the control group.

CONCLUSION

The NF-κB pathway was activated in the myocardium of OSA rabbits, which accelerated the development of MF. Early application of MAD could reduce the activation of NF-κB in the myocardium and prevent the development of MF.

The Effects of Obstructive Sleep Apnea on the Cardiovascular System: A Comprehensive Review

Obstructive sleep apnea (OSA) is an increasingly relevant cause of cardiovascular morbidity worldwide. Although the association between OSA and the cardiovascular system is well-known, the extent of its effects is still a topic of interest, including pathophysiologic mechanisms, cardiovascular sequelae, and OSA therapies and their effects. Commonly described mechanisms of cardiovascular etiologies revolve around sympathetic activation, inflammation, and intermittent hypoxia resulting from OSA. Ultimately, these effects lead to manifestations in the cardiovascular system, such as arrhythmias, hypertension, and heart failure, among others. The resulting sequelae of OSA may also have differential effects based on gender and age; several studies suggest female gender to have more susceptibility to cardiovascular mortality, as well as an increase in age. Furthermore, several therapies for OSA, both established and emerging, show a reduction in cardiovascular morbidity and may even reduce cardiovascular burden. Namely, the establishment of CPAP has led to improvement in hypertension and cardiac function in patients with heart failure and even reduced the progression of early stages of atherosclerosis. Effective management of OSA decreases abnormal neural sympathetic activity, which results in better rhythm control and blood pressure control, both in waking and sleep cycles. With newer therapies for OSA, its effects on the cardiovascular system may be significantly reduced or even reversed after long-term management. The vast extent of OSA on the cardiovascular system, as well as current and future therapeutic strategies, will be described in detail in this review.

The Hypoxic Burden, Clinical Implication of a New Biomarker in the Cardiovascular Management of Sleep Apnea Patients: A Systematic Review

Background

Obstructive sleep apnea (OSA) is a highly prevalent sleep-disordered breathing. It is associated with adverse co-morbidities, being the most scientific evidence of cardiovascular (CV) disease. Currently, OSA is measured through the apnea-hypopnea index (AHI), the total number of respiratory events per hour of sleep. However, different studies have questioned its utility in OSA management, highlighting the need to search for new parameters that better reflect the heterogeneity of the disease. Hypoxic burden (HB) has emerged as a novel biomarker that informs about the frequency, duration and depth of the desaturation related to the respiratory events. We conducted a systematic review in order to find publications about the heterogeneity of OSA measured by HB and its associations with future disease.

Methods

Systematic review was conducted using PubMed and Web of Science. The terms "sleep apne" and "hypoxic burden" were used to look for publications from the date of inception to August 15, 2023. Inclusion criteria: articles in English published in peer-reviewed journals. Exclusion criteria: (1) not available publications; (2) duplicated articles; (3) letters, editorials, and congress communications; (4) articles not including information about HB as a specific biomarker of OSA.

Results

33 studies were included. The results were classified in 2 main sections: (1) HB implication in the CV sphere: HB showed to be a better predictor of CV risk in OSA patients than traditional measures such as AHI with possible clinical management implication in OSA. (2) HB response to OSA treatment: pharmacological and nonpharmacological treatments have demonstrated to be effective in improving hypoxia measured through the HB.

Conclusions

HB could be a better and more effective parameter than traditional measurements in terms of diagnosis, risk prediction and therapeutic decisions in patients with OSA. This measure could be incorporated in sleep units and could play a role in OSA management, driving the clinic to a more personalized medicine.

Risk factors for incident cardiovascular events and their population attributable fractions in rural India: The Rishi Valley Prospective Cohort Study

OBJECTIVE

We prospectively determined incident cardiovascular events and their association with risk factors in rural India.

METHODS

We followed up with 7935 adults from the Rishi Valley Prospective Cohort Study to identify incident cardiovascular events. Using Cox proportional hazards regression, we estimated hazard ratios (HRs) with 95% confidence intervals (95% CI) for associations between potential risk factors and cardiovascular events. Population attributable fractions (PAFs) for risk factors were estimated using R ('averisk' package).

RESULTS

Of the 4809 participants without prior cardiovascular disease, 57.7% were women and baseline mean age was 45.3 years. At follow-up (median of 4.9 years, 23,180 person-years [PYs]), 202 participants developed cardiovascular events, equating to an incidence of 8.7 cardiovascular events/1000 PYs. Incidence was greater in those with hypertension (hazard ratio [HR] [95% CI] 1.73 [1.21-2.49], adjusted PAF 18%), diabetes (1.96 [1.15-3.36], 4%) or central obesity (1.77 [1.23, 2.54], 9%) which together accounted for 31% of the PAF. Non-traditional risk factors such as night sleeping hours and number of children accounted for 16% of the PAF.

CONCLUSIONS

Both traditional and non-traditional cardiovascular risk factors are important contributors to incident cardiovascular events in rural India. Interventions targeted to these factors could assist in reducing the incidence of cardiovascular events.

Weight loss and lifestyle intervention for cardiorespiratory fitness in obstructive sleep apnea: The INTERAPNEA trial

INTRODUCTION

Although recent trials have shown benefits of weight loss and lifestyle interventions on obstructive sleep apnea (OSA) severity and comorbidities, the effect of these interventions on cardiorespiratory fitness (CRF) remains unknown. This study aimed to investigate the effects of an interdisciplinary weight loss and lifestyle intervention on CRF and self-reported physical fitness in adults with OSA.

METHODS

Eighty-nine men aged 18-65 years with moderate-to-severe OSA and a body mass index ≥25 kg/m2 were randomly assigned to a usual-care group or an 8-week interdisciplinary weight loss and lifestyle intervention. CRF was assessed through the 2-km walking test, and the International Fitness Scale (IFIS) was used to assess self-reported physical fitness.

RESULTS

As compared with usual-care, the intervention group had greater improvements at intervention endpoint in objective CRF (6% reduction in 2-km walking test total time, mean between-group difference, -1.7 min; 95% confidence interval, -2.3 to -1.1), and self-reported overall physical fitness (18% increase in IFIS total score, mean between-group difference, 2.3; 95% CI 1.2 to 3.3). At 6 months after intervention, the intervention group also had greater improvements in both 2-km walking test total time (10% reduction) and IFIS total score (22% increase), with mean between-group differences of -2.5 (CI 95%, -3.1 to -1.8) and 3.0 (CI 95%, 1.8 to 4.1), respectively.

CONCLUSIONS

An 8-week interdisciplinary weight loss and lifestyle intervention resulted in significant and sustainable improvements in CRF and self-reported physical fitness in men with overweight/obesity and moderate-to-severe OSA.

STUDY REGISTRATION

ClinicalTrials.gov registration (NCT03851653).

Recent progresses in gut microbiome mediates obstructive sleep apnea-induced cardiovascular diseases

Obstructive sleep apnea (OSA) is a multifactorial sleep disorder with a high prevalence in the general population. OSA is associated with an increased risk of developing cardiovascular diseases (CVDs), particularly hypertension, and is linked to worse outcomes. Although the correlation between OSA and CVDs is firmly established, the mechanisms are poorly understood. Continuous positive airway pressure is primary treatment for OSA reducing cardiovascular risk effectively, while is limited by inadequate compliance. Moreover, alternative treatments for cardiovascular complications in OSA are currently not available. Recently, there has been considerable attention on the significant correlation between gut microbiome and pathophysiological changes in OSA. Furthermore, gut microbiome has a significant impact on the cardiovascular complications that arise from OSA. Nevertheless, a detailed understanding of this association is lacking. This review examines recent advancements to clarify the link between the gut microbiome, OSA, and OSA-related CVDs, with a specific focus on hypertension, and also explores potential health advantages of adjuvant therapy that targets the gut microbiome in OSA.

Performance of cardiorespiratory-based sleep staging in patients using beta blockers

STUDY OBJECTIVES

Automatic sleep staging based on cardiorespiratory signals from home sleep monitoring devices holds great clinical potential. Using state-of-the-art machine learning, promising performance has been reached in patients with sleep disorders. However, it is unknown whether performance would hold in individuals with potentially altered autonomic physiology, for example under the influence of medication. Here, we assess an existing sleep staging algorithm in patients with sleep disorders with and without the use of beta blockers.

METHODS

We analyzed a retrospective dataset of sleep recordings of 57 patients with sleep disorders using beta blockers and 57 age-matched patients with sleep disorders not using beta blockers. Sleep stages were automatically scored based on electrocardiography and respiratory effort from a thoracic belt, using a previously developed machine-learning algorithm (CReSS algorithm). For both patient groups, sleep stages classified by the model were compared to gold standard manual polysomnography scoring using epoch-by-epoch agreement. Additionally, for both groups, overall sleep parameters were calculated and compared between the two scoring methods.

RESULTS

Substantial agreement was achieved for four-class sleep staging in both patient groups (beta blockers: kappa = 0.635, accuracy = 78.1%; controls: kappa = 0.660, accuracy = 78.8%). No statistical difference in epoch-by-epoch agreement was found between the two groups. Additionally, the groups did not differ on agreement of derived sleep parameters.

CONCLUSIONS

We showed that the performance of the CReSS algorithm is not deteriorated in patients using beta blockers. Results do not indicate a fundamental limitation in leveraging autonomic characteristics to obtain a surrogate measure of sleep in this clinically relevant population.

CITATION

Hermans L, van Meulen F, Anderer P, et al. Performance of cardiorespiratory-based sleep staging in patients using beta blockers. J Clin Sleep Med. 2024;20(4):575-581.

Effect of the Mandibular Repositioning Appliance (MARA) on Posterior Airway Space (PAS)

Aim of the study was to show the effect of skeletal Class II treatment with the mandibular anterior repositioning appliance (MARA) on the sagittal posterior airway space (PAS) diameter. A total of 53 patients were selected retrospectively: 26 male patients (median 13 years, age span 10–19 years) and 27 female patients (median 14 years, age span 11–47 years). All patients had lateral cephalograms taken at T1 (before MARA treatment) and at T2 (after MARA treatment). Average treatment took 13.1 ± 7.5 months (Group 1) and 10.5 ± 4.5 months (Group 2), respectively. The following PAS parameters were obtained at T1 and T2: TI (Tangent Point 1), Me/Gn (menton/gnathion), DW (dorsal wall). Additionally, Björk‘s sum angle, SNA, SNB and ANB were determined. The male patients showed a higher increase in the anteroposterior diameter of the PAS (+27.5%) compared to female patients (+11.6%). Male participants had a significantly higher PAS (p = 0.006) than female participants (p = 0.09). Although not significantly, Björk‘s sum angle decreased in both groups. In general, compared to female patients, male patients showed a greater decrease between T1 and T2. SNA and SNB exhibited varied behavior between T1 and T2, with some individuals reporting a decrease and others reporting an increase. SNA tended to decrease in general. In terms of ANB, the male participants displayed a decrease from T1 to T2. Treatment of a skeletal Class II malocclusion with the mandibular anterior repositioning appliance (MARA) caused an increase in the sagittal posterior airway space (PAS) diameter and, thereby, might be effective against obstructive sleep apnea.

Effects of lifestyle factors on leukocytes in cardiovascular health and disease

Exercise, stress, sleep and diet are four distinct but intertwined lifestyle factors that influence the cardiovascular system. Abundant epidemiological, clinical and preclinical studies have underscored the importance of managing stress, having good sleep hygiene and responsible eating habits and exercising regularly. We are born with a genetic blueprint that can protect us against or predispose us to a particular disease. However, lifestyle factors build upon and profoundly influence those predispositions. Studies in the past 10 years have shown that the immune system in general and leukocytes in particular are particularly susceptible to environmental perturbations. Lifestyle factors such as stress, sleep, diet and exercise affect leukocyte behaviour and function and thus the immune system at large. In this Review, we explore the various mechanisms by which lifestyle factors modulate haematopoiesis and leukocyte migration and function in the context of cardiovascular health. We pay particular attention to the role of the nervous system as the key executor that connects environmental influences to leukocyte behaviour.

The relationship between social support and sleep quality in older adults: A review of the evidence

OBJECTIVES

Sleep quality is crucial for the health and well-being of older adults, and social support has been consistently shown to be related to sleep quality. However, there is a need for research to understand the mechanisms through which these two factors are linked. The purpose of this review is to synthesize scientific literature on the relationship between social support and sleep quality in older adults.

METHODS

Using an integrative review method, this review was conducted for a period from January 2012 to November 2022 using a combination of keywords related to social support and sleep quality in older adults.

RESULTS

A total of 21 studies that met the inclusion criteria were included. Social support was found to have a positive relationship with subjective and objective sleep quality. It may act as both a mediator between insomnia and hopelessness and a moderator buffering the influence of rumination and negative emotions on sleep quality.

CONCLUSION

This review provides evidence for the positive relationship between social support and sleep quality in older adults. Based on the findings of this review, healthcare professionals should prioritize incorporating assessments of social support and implementing interventions aimed at enhancing social support in older adults to improve their sleep quality.

Obstructive sleep apnea, nocturnal hypoxemia, and retinal microvasculature: The Atherosclerosis Risk in Communities Study

Study Objectives

Retinal microvascular pathology (RMP) and obstructive sleep apnea (OSA) are both cardiovascular disease risk factors. Limited data exists on their interrelationship. We tested the hypotheses that OSA and nocturnal hypoxemia would be associated with RMP and vessel calibers.

Methods

We conducted a quasi-cross-sectional analysis of 1625 participants in the Atherosclerosis Risk in Communities Sleep Heart Health Study. Participants completed in-home polysomnography monitoring (1996-1998) and were categorized by OSA severity (apnea-hypopnea index: <5, 5-14.9, and ≥15) and proportion of total sleep time with oxygen saturation < 90% (T90). Retinal photography (1993-1995) was used to assess RMP and measure vascular diameters (central retinal arteriolar equivalent [CRAE] and central retinal venular equivalent [CRVE]). Logistic and linear models were adjusted for demographics, behaviors, and BMI.

Results

Of the participants, 19% had OSA (AHI > 15) and 4% had RMP. Severe OSA was not associated with RMP [OR (95% CI): 1.08 (0.49 to 2.38)] or CRAE in adjusted models. OSA severity showed a positive linear relationship with CRVE; adjusted mean CRVE for those with OSA was 195.8 μm compared to 193.2 μm for those without OSA (Ptrend = 0.03). T90 was strongly associated with CRVE, but not with RMP or CRAE. Adjusted mean CRVE for T90 ≥ 5% was 199.0 and 192.9 for T90 < 1% (ptrend < 0.0001).

Conclusions

OSA and T90 were not associated with RMP or CRAE. However, both OSA and T90 ≥ 5% were associated with wider venules, which may be early and indicative changes of increased inflammation and future risk of stroke and CHD.

Aging and atrial fibrillation: A vicious circle

Atrial fibrillation (AF) is the commonest sustained cardiac arrhythmia observed in clinical practice. Its prevalence increases dramatically with advancing age. This review article discusses the recent advances in studies investigating the relationship between aging and AF and the possible underlying mechanisms.

Controversies in Sleep Apnea

This chapter discusses controversies in diagnosis and management of obstructive sleep apnea (OSA), with particular focus on surgical management to improve quality of life. Though OSA is a complex disorder that affects millions of people worldwide, its management remains controversial among clinicians. Gaps in understanding its pathophysiology, long-term health consequences, diagnostic methods, and treatment strategies exist. While continuous positive airway pressure (CPAP) therapy is considered the gold standard for moderate to severe obstructive sleep apnea (OSA), its adherence rate is often low, and its efficacy in improving outcomes beyond symptom reduction and quality of life improvement is uncertain. As such, surgical intervention may be an alternative for specific patient populations. Additionally, the type of surgical intervention may depend on individual patient needs, anatomic features, as well as preferences.

Interventional management of mitral regurgitation and sleep disordered breathing: "Catching two birds with one stone"

Sleep disordered breathing (SDB), mostly constituting of obstructive and central sleep apnea (OSA and CSA, respectively), is highly prevalent in the general population, and even more among patients with cardiovascular disease, heart failure (HF) and valvular heart disease, such as mitral regurgitation (MR). The coexistence of HF, MR and SDB is associated with worse cardiovascular outcomes and increased morbidity and mortality. Pulmonary congestion, as a result of MR, can exaggerate and worsen the clinical status and symptoms of SDB, while OSA and CSA, through various mechanisms that impair left ventricular dynamics, can promote left ventricular remodelling, mitral annulus dilatation and consequently MR. Regarding treatment, positive airway pressure devices used to ameliorate symptoms in SDB also seem to result in a reduction of MR severity, MR jet fraction and an improvement of left ventricular ejection fraction. However, surgical and transcatheter interventions for MR, and especially transcatheter edge to edge mitral valve repair (TEER), seem to also have a positive effect on SDB, by reducing OSA and CSA-related severity indexes and improving symptom control. The purpose of this review is to provide a comprehensive analysis of the common pathophysiology between SDB and MR, as well as to discuss the available evidence regarding the effect of SDB treatment on MR and the effect of mitral valve surgery or transcatheter repair on both OSA and CSA.

Barriers and enablers to screening, management and referral of sleep disorders in patients attending cardiac rehabilitation: A qualitative descriptive study

AIMS

To examine healthcare professional's knowledge about assessment and management of sleep disorders for cardiac patients and to describe the barriers to screening and management in cardiac rehabilitation settings.

DESIGN

A qualitative descriptive study. Data were collected via semi-structured interviews.

METHODS

In March 2022, a total of seven focus groups and two interviews were conducted with healthcare professionals who currently work in cardiac rehabilitation settings. Participants included 17 healthcare professionals who had undertaken cardiac rehabilitation training within the past 5 years. The study adheres to the consolidated criteria for reporting qualitative research guidelines. An inductive thematic analysis approach was utilized.

RESULTS

Six themes and 20 sub-themes were identified. Non-validated approaches to identify sleep disorders (such as asking questions) were often used in preference to validated instruments. However, participants reported positive attitudes regarding screening tools provided they did not adversely affect the therapeutic relationship with patients and benefit to patients could be demonstrated. Participants indicated minimal training in sleep issues, and limited knowledge of professional guidelines and recommended that more patient educational materials are needed.

CONCLUSION

Introduction of screening for sleep disorders in cardiac rehabilitation settings requires consideration of resources, the therapeutic relationship with patients and the demonstrated clinical benefit of extra screening. Awareness and familiarity of professional guidelines may improve confidence for nurses in the management of sleep disorders for patients with cardiac illness.

IMPACTS

The findings from this study address healthcare professionals' concerns regarding introduction of screening for sleep disorders for patients with cardiovascular disease. The results indicate concern for therapeutic relationships and patient management and have implications for nursing in settings such as cardiac rehabilitation and post-cardiac event counselling.

REPORTING METHOD

Adherence to COREQ guidelines was maintained.

PATIENT OR PUBLIC CONTRIBUTION

No Patient or Public Contribution as this study explored health professionals' experiences only.

Increased Levels of VCAM-1 in Patients with High Cardiovascular Risk and Obstructive Sleep Apnea Syndrome

(1) Background: Although obstructive sleep apnea (OSA) is associated with increased cardiovascular morbidity, the link between OSA and cardiovascular disease (CVD) is not completely elucidated. Thus, we aim to assess cardiovascular risk (CVR) using SCORE 2 and SCORE 2 for older persons (SCORE 2OP), and to evaluate the association between the endothelial biomarkers VCAM-1, ICAM-1, epicardial fat, and sleep study parameters in order to improve current clinical practices and better understand the short-and long-term CVRs in OSA patients. (2) Methods: 80 OSA patients and 37 healthy volunteers were enrolled in the study. SCORE2 and SCORE 2 OP regional risk charts (validated algorithms to predict the 10-year risk of first-onset CVD) were used for the analysis of CVR. Two-dimensional echocardiography was performed on all patients and epicardial fat thickness was measured. VCAM-1 and ICAM-1 serum levels were assessed in all patients. (3) Results: OSA patients were classified as being at high CVR, regardless of the type of score achieved. Increased EFT was observed in the OSA group. VCAM-1 was associated with a high CVR in OSA patients, but no significant correlation was observed between adhesion molecules and epicardial fat thickness. (4) Conclusions: OSA patients have a high CVR according to the SCORE 2 and SCORE 2OP risk scores. VCAM-1 may be associated with a high CVR in OSA patients. Extending conventional risk stratification scores by adding other potential biomarkers improves the risk stratification and guide treatment eligibility for CVD prevention in the OSA population.

Obstructive sleep apnoea-hypopnoea syndrome

Obstructive sleep apnoea-hypopnoea syndrome (OSAHS) is a common disorder characterised by repetitive episodes of the complete or partial collapse of the pharyngeal airway during sleep. This results in cessation (apnoea) or reduction (hypopnoea) of airflow, leading to oxygen desaturation and sleep fragmentation. An individual's disposition to develop OSAHS depends on the collapsibility of a segment of the upper airway. The degree of collapsibility can be quantified by the balance between occluding or extraluminal pressures of the surrounding tissues. Patients can experience snoring, unrefreshing sleep, witnessed apnoeas, waking with a choking sensation and excessive daytime sleepiness. OSAHS has a broad range of consequences, including cardiovascular, metabolic, and neurocognitive sequelae. Treatment options include lifestyle measures, in particular weight loss, and strategies to maintain upper airway patency overnight, including continuous positive airway pressure, mandibular advancement devices and positional modifiers.

Mediterranean Diet and Cardiovascular Disease: The Moderating Role of Adequate Sleep-Results from the ATTICA Cohort Study (2002-2022)

The relationship between diet, sleep duration and cardiovascular disease (CVD) has not been well understood. The aim of the present study was to test the potential modifying role of sleep duration in the association between adherence to the Mediterranean-type diet (MD) and CVD risk. The study consisted of n = 313 initially free-of-CVD adults, from the ATTICA cohort study (2002-2022), with available information on sleep habits. Sleep habits were categorized as inadequate and adequate sleep duration (< or ≥7 h/day, respectively). In multi-adjusted analysis, MD adherence was inversely associated with CVD risk [Hazard Ratio-HR per 1/55 in MedDietScore: 0.80, 95% Confidence Interval-CI: 0.65, 0.98]. A significant interaction between sleep duration and MedDietScore was observed (p < 0.001). In subgroup analysis, the protective association between MD adherence and CVD risk was found only in participants who slept adequately, i.e., >7 h/day [HR:0.80, 95%CI: 0.65, 0.98]. Those who had a high adherence to the MD along with adequate sleep habits, had a 70% reduced 20-year CVD risk [HR:0.30, 95%CI: 0.11, 0.80], compared to those who had a low MD adherence and inadequate sleep habits. Sleep duration should be a part of an individual's lifestyle, together with dietary and other habits, to effectively evaluate CVD risk for future events.

Acute Effect of Positive Airway Pressure on Heart Rate Variability in Obstructive Sleep Apnea

Autonomic dysregulation is associated with cardiovascular consequences in obstructive sleep apnea (OSA). This study aimed to investigate the effect of acute continuous positive airway pressure (CPAP) treatment on autonomic activity and to identify factors contributing to heart rate variability (HRV) changes in OSA. Frequency domain HRV parameters were calculated and compared between the baseline polysomnography and during the CPAP titration in 402 patients with moderate to severe OSA. There were significant reductions in total power, very low-frequency band power, low-frequency band power, and high-frequency band power during the CPAP titration as compared to the baseline polysomnography. This tendency was pronounced in male patients with severe OSA. Multivariate analysis found that changes in the apnea-hypopnea index and oxygen saturation were significantly associated with changes in sympathetic and parasympathetic activity, respectively. This study demonstrated that HRV parameters significantly changed during the CPAP titration, indicating a beneficial effect of CPAP in the restoration of sympathetic and parasympathetic hyperactivity in OSA. Prospective longitudinal studies should determine whether long-term CPAP treatment aids in maintaining the long-lasting improvement of the autonomic functions, thereby contributing to the prevention of cardiovascular and cerebrovascular diseases in patients with OSA.

Cut-off points of neck and waist circumference as predictors of obstructive sleep apnea in the Colombian population: a comparison with polysomnography

BACKGROUND

Neck circumference (NC) is a useful anthropometric measure for predicting obstructive sleep apnea (OSA). Ethnicity and sex also influence obesity phenotypes. NC cut-offs for defining OSA have not been established for the Latin American population.

OBJECTIVES

To evaluate NC, waist circumference (WC), and body mass index (BMI) as predictors of OSA in the Colombian population and to determine optimal cut-off points.

DESIGN AND SETTING

Diagnostic tests were conducted at the Javeriana University, Bogota.

METHODS

Adults from three cities in Colombia were included. NC, WC, and BMI were measured, and a polysomnogram provided the reference standard. The discrimination capacity and best cut-off points for diagnosing OSA were calculated.

RESULTS

964 patients were included (57.7% men; median age, 58 years) and 43.4% had OSA. The discrimination capacity of NC was similar for men and women (area under curve, AUC 0.63 versus 0.66, P = 0.39) but better for women under 60 years old (AUC 0.69 versus 0.57, P < 0.05). WC had better discrimination capacity for women (AUC 0.69 versus 0.57, P < 0.001). There were no significant differences in BMI. Optimal NC cut-off points were 36.5 cm for women (sensitivity [S]: 71.7%, specificity [E]: 55.3%) and 41 cm for men (S: 56%, E: 62%); and for WC, 97 cm for women (S: 65%, E: 69%) and 99 cm for men (S: 53%, E: 58%).

CONCLUSIONS

NC and WC have moderate discrimination capacities for diagnosing OSA. The cut-off values suggest differences between Latin- and North American as well as Asian populations.