Obstructive Sleep Apnoea and Lipid Metabolism: The Summary of Evidence and Future Perspectives in the Pathophysiology of OSA-Associated Dyslipidaemia

Radiofrequency Coblation Inferior Turbinoplasty with Modified UPPP for the Treatment of Obstructive Sleep Apnea-Hypopnea Syndrome

Objective: To compare the efficacy of surgical treatment in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) involving a standalone modified uvulopalatopharyngoplasty (mUPPP) and radiofrequency coblation inferior turbinoplasty with mUPPP. Methods: In this study, a retrospective analysis of 79 OSAHS patients with inferior turbinate hypertrophy and oropharyngeal obstruction undergoing surgical treatment was performed. According to the different surgical methods, the patients were divided into 2 groups (Group A and Group B). Group A included 36 patients treated with standalone mUPPP. Group B included 43 patients treated with mUPPP and bilateral radiofrequency coblation inferior turbinoplasty. Polysomnography (PSG), active anterior rhinomanometry, surgical success rate, and surgical complication were used to assess the patients in 2 groups. The successful surgical result was defined as a 50% or greater decrease in the apnea-hypopnea index (AHI) in postoperative PSG. Results: Before surgery, there were no significant differences in age, gender, neck circumference, body mass index, Friedman tongue position grade, tonsil size grade, Epworth sleepiness scale score, total inferior turbinate size grade, total nasal resistance (TNR), AHI and the lowest O2 saturation (LSaO2) between the 2 groups. After 6 months of follow-up visits, AHI, LSaO2, and TNR in Group B showed a significant improvement compared to Group A. The surgical success rate was 76.74% in Group B compared to 52.78% in Group A (P = .025). There was no significant difference in the total surgical complication rate between the 2 groups (13.89% vs 23.26%, P = .290). Conclusion: For OSAHS patients with inferior turbinate hypertrophy and oropharyngeal obstruction, radiofrequency coblation inferior turbinoplasty with mUPPP appears to be a more effective surgical method than mUPPP alone.

Investigating the Role of Scd1 in OSAHS-Induced Vascular Changes

This study investigates the role of Stearoyl-CoA Desaturase-1 (Scd1) in vascular remodeling associated with Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS) using multi-omics analysis. Transcriptomic and metabolomic datasets of OSAHS mouse models were analyzed to identify differentially expressed genes and metabolites, followed by functional enrichment analysis. Key genes were screened using weighted gene correlation network analysis (WGCNA) and machine learning, and a PPI network was constructed. An OSAHS mouse model was developed via intermittent hypoxia exposure. Human aortic smooth muscle cells (HASMCs) were subjected to hypoxia/reoxygenation cycles to simulate OSAHS in vitro. Blood pressure, plasma lipid profiles, histological changes in the thoracic aorta, and Scd1 protein expression were assessed. CCK-8 and Transwell assays evaluated HASMC proliferation and migration. Scd1 was identified as a critical factor in OSAHS-related vascular remodeling, with its expression significantly upregulated in vascular tissues of OSAHS mice. Metabolomic analysis revealed changes in fatty acid metabolism. Scd1 knockdown reduced blood pressure, lipid levels, aortic wall thickness, collagen deposition, elastic fiber accumulation, and mucin deposition in vivo. In vitro, hypoxia/reoxygenation cycles elevated Scd1 expression, while Scd1 knockdown inhibited HASMC proliferation and migration. Multi-omics analyses highlight Scd1 as a key regulator in OSAHS-associated vascular remodeling, driving pathological changes through its upregulation. These findings suggest Scd1 as a potential therapeutic target for managing OSAHS-related vascular pathologies.

Intermittent hypoxia increases lipid insulin resistance in healthy humans: A randomized crossover trial

Sympathetic overactivity caused by chronic intermittent hypoxia is a hallmark of obstructive sleep apnea. A high sympathetic tone elicits increases in plasma free fatty acid and insulin. Our objective was to assess the impact of 14 nights of chronic intermittent hypoxia exposure on sympathetic activity, glucose control, lipid profile and subcutaneous fat tissue remodelling in non-obese healthy humans. In this prospective, double-blinded crossover study, 12 healthy subjects were randomized, among them only nine underwent the two phases of exposures of 14 nights chronic intermittent hypoxia versus air. Sympathetic activity was measured by peroneal microneurography (muscle sympathetic nerve activity) before and after each exposure. Fasting glucose, insulin, C-peptide and free fatty acid were assessed at rest and during a multisampling oral glucose tolerance test. We assessed histological remodelling, adrenergic receptors, lipolysis and lipogenesis genes expression and functional changes of the adipose tissue. Two weeks of exposure of chronic intermittent hypoxia versus ambient air significantly increased sympathetic activity (p = 0.04). Muscle sympathetic nerve activity increased from 24.5 [18.9; 26.8] before to 21.7 [13.8; 25.7] after ambient air exposure, and from 20.6 [17.4; 23.9] before to 28.0 [24.4; 31.5] bursts per min after exposure to chronic intermittent hypoxia. After chronic intermittent hypoxia, post-oral glucose tolerance test circulating free fatty acid area under the curve increased (p = 0.05) and free fatty acid sensitivity to insulin decreased (p = 0.028). In adipocyte tissue, intermittent hypoxia increased expression of lipolysis genes (adipocyte triglyceride lipase and hormone-sensitive lipase) and lipogenesis genes (fatty acid synthase; p < 0.05). In this unique experimental setting in healthy humans, chronic intermittent hypoxia induced high sympathetic tone, lipolysis and decreased free fatty acid sensitivity to insulin. This might participate in the trajectory to systemic insulin resistance and diabetes for patients with obstructive sleep apnea.

Non-linear association between weight-adjusted-waist index and obstructive sleep apnea: a cross-sectional study from the NHANES (2005-2008 to 2015-2020)

Background

The principal objective of the present investigation is to undertake an in-depth exploration of the relationship that exists between the newly introduced weight-adjusted waist index (WWI), employed as a surrogate way for corpulence, and obstructive sleep apnea (OSA).

Methods

Analysis using cross-sectional data from 11,545 NHANES participants across 2005-2008 and 2015-2020. Obesity via WWI (waist circumference over sqrt of body weight). OSA via 3 NHANES QnA items: monthly excessive sleepiness, weekly wheezing/snoring/breathing stoppage, weekly snoring. Relationships between WWI and OSA probed with weighted multivariate logistic regression and smoothed curve fitting. Also did subgroup, interaction tests and threshold effect analysis. Excluded those with incomplete WWI, OSA or hypertension data as they might have different health profiles. We excluded participants with incomplete data on WWI, OSA, or hypertation-related items, as those with missing data might have different health profiles.

Results

The study, encompassing a cohort of 11,545 participants, revealed that 5,727 individuals were diagnosed with OSA. Upon conducting fully adjusted models, A positive relevance between WWI and OSA was established, with an odds ratio of 1.57 (95% CI: 1.44, 1.71), indicating a significant relationship. Notably, participants falling within the highest quartile of WWI exhibited a markedly heightened propensity for OSA, being 2.58 times more likely to suffer from it than those in the bottom quartile [OR: 2.58 (95% CI: 2.10, 3.17)]. Rigorous subgroup analyses and interaction tests further confirmed the robustness of this positive association across various subgroups, thereby affirming the consistency of the observed relationship. Additionally, a noteworthy non-linear association and saturation phenomenon were discerned between the WWI and OSA, demarcated by an inflection point at 11.70 cm/√kg.

Conclusion

Our research has clearly shown a significant positive correlation, along with a saturation effect, between WWI and OSA in the American population. However, the cross-sectional design limits causal inference, and the exclusion of certain participants may affect the generalizability of the findings. Future longitudinal studies are needed to explore causality and address potential biases associated with participant exclusion, ultimately improving the broader applicability of the results.

Characteristics and clinical value of intestinal metabolites in 4 to 6-year-old children with OSAHS

OBJECTIVE

This study aims to explore the characteristics and functional changes of intestinal metabolites in children with obstructive sleep apnea hypopnea syndrome (OSAHS) aged 4-6 years old through metabolomic approaches, screen potential biomarkers and analyze their correlation with clinical indicators and preliminary discuss the roles of intestinal metabolites in the occurrence and development of OSAHS.

METHODS

We collected fecal samples from 40 OSAHS children and 40 healthy controls aged 4-6 years and recorded some OSAHS-related clinical indicators. Fecal specimens were used to detect all metabolites through untargeted metabolomics.

RESULTS

This study identified a total of 1164 intestinal metabolites and screened out 254 differential metabolites. In the OSAHS group, the relative content of 96 metabolites were higher than the control group, while the relative content of 158 metabolites were lower. The receiver operating characteristic curve analysis results showed that the area under the curve of 14 differential metabolites was greater than 0.8. The area under the curve of Formononetin is the highest, at 0.9100, with sensitivity and specificity of 82.5% and 90.0%, respectively, and is positively correlated with OAHI. The differential metabolite functions mainly include the metabolism of fatty acids and other lipid substances, cellular signaling, protein and amino acid related metabolism, disease-related functions, glucose metabolism, and vitamin metabolism.

CONCLUSION

The intestinal metabolites and metabolic function of 4-to-6-year-old children with OSAHS altered. There was a correlation between differential metabolites and clinical indicators such as uric acid, hemoglobin, and blood sugar, which has potential diagnostic value for OSAHS screening.

Cross-sectional study of the association between triglyceride glucose-body mass index and obstructive sleep apnea risk

BACKGROUND

The triglyceride glucose-body mass index (TyG-BMI) is a novel indicator of insulin resistance (IR). Obstructive sleep apnea (OSA) is a prevalent disorder characterized by recurrent complete or partial collapse of the pharyngeal airway during sleep; however, the relationship between these two conditions remains unexplored. We hypothesized that a higher TyG-BMI is associated with the occurrence of OSA.

AIM

To assess the association between TyG-BMI and OSA in adults in the United States.

METHODS

A cross-sectional study was conducted utilizing data from the National Health and Nutrition Examination Surveys spanning from 2005-2008 to 2015-2018. TyG-BMI was calculated as Ln [triglyceride (mg/dL) × fasting blood glucose (mg/dL)/2] × BMI. Restricted cubic splines were used to analyze the risk of TyG-BMI and OSA occurrence. To identify potential nonlinear relationships, we combined Cox proportional hazard regression with smooth curve fitting. We also conducted sensitivity and subgroup analyses to verify the robustness of our findings.

RESULTS

We included 16794 participants in the final analysis. Multivariate regression analysis showed that participants with a higher TyG-BMI had a higher OSA incidence. After adjusting for all covariates, TyG-BMI was positively correlated with the prevalence of OSA (odds ratio: 1.28; 95% confidence interval: 1.17, 1.40; P < 0.001); no significant nonlinear relationship was observed. Subgroup analysis showed no strong correlation between TyG-BMI and OSA in patients with diabetes. The correlation between TyG-BMI and OSA was influenced by age, sex, smoking status, marital status, hypertensive stratification, and obesity; these subgroups played a moderating role between TyG-BMI and OSA. Even after adjusting for all covariates, there was a positive association between TYG-BMI and OSA prevalence.

CONCLUSION

A higher TyG-BMI index is linked to higher chances of developing OSA. As TyG-BMI is an indicator of IR, managing IR may help reduce the risk of OSA.

The long-term impact of hypertriglyceridemia-waist phenotype on major adverse cardiovascular events in elderly patients with OSA

INTRODUCTION

The hypertriglyceridemia-waist (HTGW) phenotype is a prevalent risk factor for cardiovascular diseases and obstructive sleep apnea (OSA). However, the impactof the HTGW phenotype on the simultaneous occurrence of OSA and cardiovascular diseases remains unexplored. This study aimed to determine whether the HTGW phenotype elevates the incidence of major adverse cardiovascular events (MACE) in patients with OSA, such as hospitalization for unstable angina and heart failure, myocardial infarction, and cardiovascular death, in patients with OSA.

METHODS

A total of 1,290 patients with OSA were recruited from six hospitals for follow-up. According to the Chinese population criteria recommended by the International Diabetes Federation, the patients were divided into four groups: normal triglyceride waist circumference (NTNW) phenotype, pure high triglyceride (HTNW) phenotype, pure high waist circumference (NTGW) phenotype, and HTGW phenotype. The prognosis for MACE was evaluated using Cox proportional hazards analysis. The prognosis of MACE was evaluated using Cox proportional hazards analysis.

RESULTS

207 (17.9%) developed an HTGW phenotype. After a median of 42 months of follow-up, 119 (10.3%) experienced MACE. Cox proportional hazards analysis revealed that patients exhibiting the HTGW phenotype had a 1.963-fold higher risk of developing MACE than patients with the NTNW phenotype (P = 0.012). These results remained significant after adjusting for confounders, and a 2.186-fold increased risk of MACE was found in patients with NTGW phenotype (P = 0.012). Subgroup analyses revealed an increased risk of MACE in OSA patients with HTGW phenotype and NTGW phenotype that were older than or equal to 70 years, male, and had moderate-to-severe OSA (all P-values < 0.05).

CONCLUSION

The HTGW and NTGW phenotypes significantly increase MACE risk among elderly patients with OSA.

Association between METS-IR index and obstructive sleep apnea: evidence from NHANES

Insulin resistance (IR) is strongly associated with obstructive sleep apnea (OSA). Whereas, few studies have focused on the potential association between the Metabolic Score for Insulin Resistance (METS-IR), a novel non-insulin-dependent IR index, and OSA. Subjects from the National Health and Nutrition Examination Survey (NHANES) spanning 2005-2008 and 2015-2018 were recruited. The potential relationship between METS-IR and other IR indices with OSA was explored through three logistic regression analysis models and restricted cubic spline (RCS) curves. Receiver operating characteristic (ROC) curves were used to assess the diagnostic value of these indicators for OSA. On the basis of age, sex, race, body mass index (BMI), hypertension, diabetes， and cardiovascular disease (CVD), subgroup analyses were conducted to test the robustness of the METS-IR and OSA relationship. A total of 8,306 participants were enrolled, with an OSA prevalence of 30.69%. After adjusting for potential confounders, METS-IR, the triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio, the triglyceride glucose Index (TyG), and the homeostatic model assessment of insulin resistance (HOMA-IR) showed positive associations with OSA prevalence. In the highest tertile of METS-IR, TG/HDL-C, TyG index, and HOMA-IR, OSA prevalence was 2.96-fold, 1.42-fold, 1.29-fold, and 1.41-fold higher, respectively, compared to the lowest tertile (METS-IR: OR = 2.96, 95% CI: 2.50, 3.52, P < 0.0001; TG/HDL-C: OR = 1.42, 95% CI: 1.17, 1.73, P < 0.001; TyG index: OR = 1.29, 95% CI: 1.07, 1.55, P = 0.008; HOMA-IR: OR = 1.41, 95% CI: 1.18, 1.69, P < 0.001). ROC analysis revealed that METS-IR had the highest diagnostic accuracy for OSA (AUC = 0.652). The positive associations between these four IR indices and OSA remain stable across most cases (P for interaction > 0.05); however, all of them show significant interactions with diabetes (P for interaction < 0.05). The METS-IR index is positively associated with the prevalence of OSA and shows superior diagnostic accuracy compared to HOMA-IR, TG/HDL-C, and TyG index.

Association of Serum Ferritin Levels With Obstructive Sleep Apnea in Overweight/Obese US Populations: A Population-Based Study From the NHANES

Objective

To investigate the relationship between serum ferritin levels and OSA in overweight/obese individuals and assess the association between ferritin levels and all-cause mortality in overweight/obese female OSA patients.

Methods

Cross-sectional (n = 4,809) and prospective (n = 832) data from overweight/obese adults from the 2005-2008, and 2015-March 2020 NHANES cycles were analyzed. Participants were categorized into quartiles (Q1-Q4) based on their ln-transformed serum ferritin levels. Multivariable logistic regression and restricted cubic spline regression (RCS) investigate associations. Kaplan-Meier survival analyses and Cox proportional hazards regression examined the relationship between ferritin levels and all-cause mortality in OSA patients.

Results

After adjusting for potential confounding factors, we found that ln-transformed ferritin levels were associated with an increased risk of OSA (Q4 vs Q2: OR = 1.07, 95% CI: 1.01-1.13, P = 0.020, P for trend = 0.010). A non-linear U-shaped association was observed between ferritin levels and OSA risk (P-non-linear = 0.029), with an inflection point at ln-transformed ferritin of 4.58 (corresponding to a serum ferritin concentration of 97.51 ng/mL). In female OSA patients, elevated ferritin levels were associated with increased all-cause mortality risk (Q4 vs Q2: HR: 5.46, 95% CI: 1.18-25.16, P = 0.029, P for trend = 0.032).

Conclusion

Ferritin levels in overweight/obese individuals show a U-shaped relationship with OSA risk, and elevated levels correlate with increased all-cause mortality in female overweight/obese OSA patients. In the future, further research is needed to explore the potential associations between ferritin, inflammation, obesity, and OSA.

Exploring the pharmacological mechanisms for alleviating OSA: Adenosine A2A receptor downregulation of the PI3K/Akt/HIF‑1 pathway (Review)

Obstructive sleep apnea (OSA) is the most common type of sleep apnea, which leads to episodes of intermittent hypoxia due to obstruction of the upper airway. A key feature of OSA is the upregulation and stabilization of hypoxia-inducible factor 1 (HIF-1), a crucial metabolic regulator that facilitates rapid adaptation to changes in oxygen availability. Adenosine A2A receptor (A2AR), a major adenosine receptor, regulates HIF-1 under hypoxic conditions, exerting anti-inflammatory properties and affecting lipid metabolism. The present study explored the roles of A2AR in OSA regulation, specifically focusing on its effects via the PI3K/Akt/HIF-1 pathway. The findings enhance our understanding the pharmacological potential of A2AR in OSA management and suggest future research directions in exploring its clinical applications.

Exploring the therapeutic potential of GLP-1 receptor agonists in the management of obstructive sleep apnea: a comprehensive review

Obstructive Sleep Apnea (OSA) is a prevalent sleep disorder marked by repeated episodes of partial or complete upper airway obstruction during sleep, which leads to intermittent hypoxia and fragmented sleep. These disruptions negatively impact cardiovascular health, metabolic function, and overall quality of life. Obesity is a major modifiable risk factor for OSA, as it contributes to both anatomical and physiological mechanisms that increase the likelihood of airway collapse during sleep. While continuous positive airway pressure (CPAP) therapy remains the gold standard for OSA treatment, its limitations - particularly issues with patient adherence - underscore the need for alternative or adjunct therapeutic options. One such option is the use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs), which are widely recognized for their ability to reduce body weight and improve metabolic health. Emerging evidence suggests that GLP-1 RAs may offer therapeutic benefits in managing OSA, particularly by addressing obesity, a key contributor to the condition. This narrative review seeks to explore the role of GLP-1 RAs in the treatment of OSA, evaluating their efficacy in reducing OSA severity and discussing their broader clinical implications for future research and practice.

The association between cardiovascular health and obstructive sleep apnea symptoms: findings from NHANES

Objective

To investigate the association between cardiovascular health (CVH) and obstructive sleep apnea (OSA) within the U.S. population.

Methods

This study enrolled 12,540 participants aged 20 years and older from the 2007-2008 and 2015-2018 cycles of the National Health and Nutrition Examination Surveys (NHANES). Weighted univariate and multivariate logistic regression were utilized to examine the relationship between CVH and OSA symptoms. Life's Essential 8 (LE 8) metrics was employed to evaluate the CVH status of participants. Identification of OSA symptoms was determined based on a sleep questionnaire. They include (1) how often you snore; (2) how often you snort/stop breathing; or (3) how often you feel overly sleepy during day. Individuals who answered that they snore 3 or more per week; snort/stop breathing 3 or more per week and feel overly sleepy during day 16-30 times per month were classified as having OSA symptoms.

Results

Significant inverse associations were observed between LE8 scores and symptoms of OSA after adjusting for covariates. The 95% CI was 0.750 (0.630,0.893) for the moderate CVH group and 0.573 (0.454,0.723) for the high CVH group. Subgroup analyses, stratified by age and gender, highlighted a significant interaction between LE8 scores and OSA symptoms with age (P < 0.0001). Participants under 60 years old in the high CVH group exhibited a reduced likelihood OSA symptoms (OR: 0.470; 95% CI: 0.345,0.641). Restricted cubic splines (RCS) in a multivariate regression analysis showed a non-linear relationship between LE8 score and OSA. Our finding demonstrates a substantial decrease in OSA symptom prevalence with increased LE 8 scores.

Conclusion

The results demonstrate a strong inverse correlation between LE8 scores and OSA symptoms. Participants with higher LE8 scores showed a reduced likelihood of experiencing OSA symptoms.

Association between metabolic score for visceral fat and obstructive sleep apnea: a cross-sectional study

Background

Previous studies have established a connection between obesity and obstructive sleep apnea (OSA), novel surrogate markers of adipose accumulation may serve as more critical and reliable factors for consideration. Consequently, this study aims to explore and elucidate the correlation between metabolic score for visceral fat (METS-VF) and OSA.

Methods

In this cross-sectional study, the data from the National Health and Nutrition Examination Survey (NHANES) during the period from 2013 to 2020 were adopted. Through multivariate logistic regression, restricted cubic spline regression (RCS), subgroup analyses and sensitivity analyses, the correlation between METS-VF and OSA was explored.

Results

Among 8,284 subjects, 4,176 of them were categorized as having OSA. It was observed that the quartile range of METS-VF increased, with a notable rise in the prevalence of OSA (32.8% vs. 49.8% vs. 56.9% vs. 62.1%, p < 0.001). Logistic regression analyses showed a significant positive correlation between METS-VF and the risk of having OSA, even after accounting for potential confounders (OR = 2.436, 95% CI: 2.065, 2.874). Subgroup analyses further revealed a stronger correlation between OSA and METS-VF among subjects who were female, younger, and Mexican Americans. RCS regression identified a positive linear correlation, without threshold effects. Sensitivity analyses with stop breathing (OR = 2.283, 95%CI: 1.169, 3.070) or snoring (OR = 2.716, 95%CI: 2.273, 3.246) as outcomes reaffirmed the positive correlation with METS-VF.

Conclusion

Elevated METS-VF demonstrated a linear correlation with the increased incidence of OSA, suggesting the potential utility as a predictive index for OSA.

The relationship between composite lipid indices and baveno classification in patients with obstructive sleep apnoea

Obstructive Sleep Apnoea (OSA) is associated with the development of cardiovascular disease (CVD); however, the risk is only weekly related to OSA severity traditionally determined by the apnoea-hypopnoea index. The Baveno classification was developed to improve patient selection who would benefit from OSA treatment in terms of symptoms improvement and CVD risk reduction. However, it is unclear how the classification relates to biomarkers of CVD risk. Composite lipid indices were evaluated in various populations and showed good predictive value for incident CVD. One thousand two hundred and forty-two patients with OSA were included in the study. Composite lipid indices, including the atherogenic index of plasma (AIP), visceral adiposity index (VAI), lipid accumulation product (LAP) and cardiometabolic index (CMI) were compared between different Baveno groups (A - minor symptoms, minor comorbidities, B - severe symptoms, minor comorbidities, C - minor symptoms, severe comorbidities, D - severe symptoms, severe comorbidities). All composite lipid indices were higher in group D versus groups A and C. Only LAP (86.93 /58.40-119.49/ vs. 75.73 /48.37-99.04/) and CMI (1.03 /0.69-1.42/ vs. 0.91 /0.63-1.12/) were significantly different between the minimally symptomatic groups (C vs. A), and solely LAP was significantly higher (110.69 /76.76-147.22/ vs. 82.32 /60.35-113.50/) when the highly symptomatic groups (D vs. B) were compared. The Baveno classification correlates with cardiovascular risk estimated with composite lipid indices. Composite lipid indices may help better stratifying cardiovascular risk in both minimally- and highly symptomatic patients.

T266M variants of ANGPTL4 improve lipid metabolism by modifying their binding affinity to acetyl-CoA carboxylase in obstructive sleep apnea

BACKGROUND

Angiopoietin-like protein 4 (ANGPTL4) is recognized as a crucial regulator in lipid metabolism. Acetyl-CoA carboxylases (ACACAs) play a role in the β-oxidation of fatty acids. Yet, the functions of ANGPTL4 and ACACA in dyslipidemia of obstructive sleep apnea (OSA) remain unclear.

METHODS

This study included 125 male OSA subjects from the Shanghai Sleep Health Study (SSHS) who were matched for age, body mass index (BMI), and lipid profile. Serum ANGPTL4 levels were measured via ELISA. The ANGPTL4 T266M variants of 4455 subjects along with their anthropometric, fasting biochemical, and standard polysomnographic parameters were collected. Linear regression was used to analyze the associations between quantitative traits and ANGPTL4 T266M. Molecular docking and molecular dynamic simulation were employed to compare the effects of the wild-type ANGPTL4 and its T266M mutation on ACACA.

RESULTS

Serum ANGPTL4 levels significantly decreased with increasing OSA severity (non-OSA: 59.6 ± 17.4 ng/mL, mild OSA: 50.0 ± 17.5 ng/mL, moderate OSA: 46.3 ± 15.5 ng/mL, severe OSA: 19.9 ± 14.3 ng/mL, respectively, p = 6.02 × 10-16). No associations were found between T266M and clinical characteristics. Molecular docking indicated that mutant ANGTPL4 T266M had stronger binding affinity for the ACACA protein, compared with wild-type ANGPTL4. In terms of protein secondary structure, mutant ANGTPL4 T266M demonstrated greater stability than wild-type ANGPTL4.

CONCLUSIONS

Serum ANGTPL4 levels were significantly decreased in OSA patients, particularly among individuals with severe OSA. Although functional ANGTPL4 T266M variants were not associated with lipid levels in OSA, ANGTPL4 T266M could enhance binding affinity for the ACACA protein, potentially regulating lipid metabolism.

Effect of continuous positive airway pressure on cardiometabolic risk factors in patients with obstructive sleep apnea: A systematic review and meta-analysis

OBJECTIVE

Cardiometabolic risk factors (CMRFs) play a crucial role in the occurrence and development of cardiovascular diseases. Obstructive sleep apnea (OSA) causes abnormalities of CMRFs. Continuous positive airway pressure (CPAP) is a widely used treatment for OSA. This systematic review and meta-analysis aimed to investigate the effect of CPAP on CMRFs in patients with OSA.

METHODS

A search of PubMed, Cochrane Library, Scopus, Web of Science, and Embase was conducted to find randomized controlled trials up to December 3, 2023. The quality of the studies included was evaluated using the Cochrane Bias Risk Tool 2.0, and a meta-analysis was carried out using Stata15.1 software. The effect sizes for this meta-analysis were represented as the weighted mean difference (WMD) and 95 % confidence interval (CI).

RESULTS

A total of 52 studies with 10,104 participants were analyzed. The results showed that CPAP significantly lowered systolic blood pressure (WMD: -2.04 mmHg; 95%CI: -3.56 to -0.51), diastolic blood pressure (WMD: -1.40 mmHg; 95%CI: -2.36 to -0.44), total cholesterol (WMD: -0.27 mmol/L; 95%CI: -0.51 to -0.04), triglycerides (WMD: -0.02 mmol/L; 95%CI: -0.03 to -0.01), and fasting blood glucose (WMD: -0.15 mmol/L; 95%CI: -0.16 to -0.13) in patients with OSA. However, there was no significant change in low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, waist circumference, or body mass index after CPAP.

CONCLUSION

In summary, this meta-analysis demonstrated that CPAP effectively reduced certain CMRFs in patients with OSA, offering new insights for cardiovascular disease prevention.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, identifier CRD42023456380.

Cardio-Lipotoxicity of Epicardial Adipose Tissue

Epicardial adipose tissue is a unique visceral adipose tissue depot that plays a crucial role in myocardial metabolism. Epicardial adipose tissue is a major source of energy and free fatty acids for the adjacent myocardium. However, under pathological conditions, epicardial fat can affect the heart through the excessive and abnormal influx of lipids. The cardio-lipotoxicity of the epicardial adipose tissue is complex and involves different pathways, such as increased inflammation, the infiltration of lipid intermediates such as diacylglycerol and ceramides, mitochondrial dysfunction, and oxidative stress, ultimately leading to cardiomyocyte dysfunction and coronary artery ischemia. These changes can contribute to the pathogenesis of various cardio-metabolic diseases including atrial fibrillation, coronary artery disease, heart failure, and obstructive sleep apnea. Hence, the role of the cardio-lipotoxicity of epicardial fat and its clinical implications are discussed in this review.

Influence of sleep on physiological systems in atherosclerosis

Sleep is a fundamental requirement of life and is integral to health. Deviation from optimal sleep associates with numerous diseases including those of the cardiovascular system. Studies, spanning animal models to humans, show that insufficient, disrupted or inconsistent sleep contribute to poor cardiovascular health by disrupting body systems. Fundamental experiments have begun to uncover the molecular and cellular links between sleep and heart health while large-scale human studies have associated sleep with cardiovascular outcomes in diverse populations. Here, we review preclinical and clinical findings that demonstrate how sleep influences the autonomic nervous, metabolic and immune systems to affect atherosclerotic cardiovascular disease.

Biological sex-related differences in the postprandial triglyceride response to intermittent hypoxaemia in young adults: a randomized crossover trial

Obstructive sleep apnoea is characterized by chronic intermittent hypoxaemia and is independently associated with an increased risk of metabolic comorbidities (e.g. type II diabetes and ischaemic heart disease). These comorbidities could be attributable to hypoxaemia-induced alterations in blood lipid profiles. However, it remains unclear whether intermittent hypoxaemia alters triglyceridaemia differently between biological sexes. Therefore, we used a randomized crossover design to examine whether 6 h of moderate intermittent hypoxaemia (15 hypoxaemic cycles/h, 85% oxyhaemoglobin saturation) alters plasma triglyceride levels differently between men and women after a high-fat meal. Relative to men, women displayed lower levels of total triglycerides, in addition to denser triglyceride-rich lipoprotein triglycerides (TRL-TG; mainly very low-density lipoprotein triglycerides and chylomicron remnant triglycerides) and buoyant TRL-TG (mainly chylomicron triglycerides) during normoxia (ambient air) and intermittent hypoxaemia (sex × time: all P ≤ 0.008). Intermittent hypoxaemia led to higher triglyceride levels (condition: all P ≤ 0.016); however, this effect was observed only in men (sex × condition: all P ≤ 0.002). Compared with normoxia, glucose levels were higher in men and lower in women during intermittent hypoxaemia (sex × condition: P < 0.001). The different postprandial responses between biological sexes occurred despite similar reductions in mean oxyhaemoglobin saturation and similar elevations in insulin levels, non-esterified fatty acid levels and mean heart rate (sex × condition: all P ≥ 0.185). These results support growing evidence showing that intermittent hypoxaemia impacts men and women differently, and they might help to explain biological sex-related discrepancies in the rate of certain comorbidities associated with intermittent hypoxaemia. KEY POINTS: Intermittent hypoxaemia is a key characteristic of obstructive sleep apnoea and alters lipid metabolism in multiple tissues, resulting in increased circulating triglyceride levels, an important risk factor for cardiometabolic diseases. Circulating triglyceride levels are regulated differently between biological sexes, with women typically displaying much lower fasting and postprandial triglyceride levels than men, partly explaining why women of all ages experience lower mortality rates from cardiometabolic diseases. In this study, healthy young men and women consumed a high-fat meal and were then exposed to 6 h of intermittent hypoxaemia or ambient air. We show that postprandial triglyceride levels are significantly lower in women compared with men and that intermittent hypoxaemia leads to higher postprandial triglyceride levels in men only. These results might help us to understand better why women living with obstructive sleep apnoea experience lower rates of cardiometabolic diseases (e.g. type II diabetes and ischaemic heart disease) than men living with obstructive sleep apnoea.

Obstructive sleep apnoea is independently associated with non-alcoholic fatty pancreatic disease

PURPOSE

This study investigated the prevalence of non-alcoholic fatty pancreatic disease (NAFPD) in patients with obstructive sleep apnoea (OSA) and analysed the correlation between them.

MATERIALS AND METHODS

Patients who underwent polysomnography and modified abdominal ultrasound examinations were continuously enrolled and divided into OSA and control groups. The OSA group was further divided into NAFPD and non-NAFPD groups. Differences in various indicators were compared. Binary logistic regression analyses were conducted to identify factors influencing NAFPD.

RESULTS

A total of 210 participants were included in the study, including 178 in the OSA group and 32 in the control group. The prevalence of NAFPD, weight, body mass index (BMI), and other indicators were significantly higher in the OSA group than that in the control group (p < 0.05). The above indices, prevalence of hypertension and metabolic associated steatotic liver disease (MASLD), and severity of sleep apnoea were higher in the NAFPD group than that in the non-NAFPD group (p < 0.05). Binary logistic regression analysis showed a 4.4% increased risk of NAFPD for each unit increase in apnea-hypopnea index (AHI) after adjusting for BMI and hypertension.

CONCLUSION

The prevalence of NAFPD was higher in the OSA group than that in the control group, and chronic intermittent hypoxia was strongly associated with pancreatic fat infiltration; AHI, BMI, and hypertension were independent risk factors for NAFPD. The NAFPD group had a higher prevalence of obesity and some other diseases.

Therapeutic Potential of Glucagon-like Peptide-1 Receptor Agonists in Obstructive Sleep Apnea Syndrome Management: A Narrative Review

Background: Obstructive Sleep Apnea (OSA) is a prevalent disorder characterized by repetitive upper airway obstructions during sleep, leading to intermittent hypoxia and sleep fragmentation. Current treatments, particularly Continuous Positive Airway Pressure (CPAP), face adherence challenges, necessitating novel therapeutic approaches. Methods: This review explores the potential of Glucagon-like Peptide-1 receptor agonists (GLP-1RA), commonly used for type 2 diabetes and obesity, in managing OSA. GLP-1RA promotes weight loss, enhances insulin sensitivity, and exhibits anti-inflammatory and neuroprotective properties, potentially addressing key pathophysiological aspects of OSA. Results: Emerging evidence suggests that these agents may reduce OSA severity by decreasing upper airway fat deposition and improving respiratory control. Clinical trials have demonstrated significant reductions in the Apnea-Hypopnea Index (AHI) and improvements in sleep quality with GLP-1 therapy. Conclusions: Future research should focus on elucidating the mechanisms underlying GLP-1 effects on OSAS, optimizing combination therapies, and identifying patient subgroups that may benefit the most. Integrating GLP-1RA into OSAS management could revolutionize treatment by addressing both the metabolic and respiratory components of the disorder, ultimately enhancing patient outcomes.

Association between triglyceride glucose-body mass index and obstructive sleep apnea: a study from NHANES 2015-2018

Background

The association between TyG-BMI index and the risk of obstructive sleep apnea (OSA), a recently identified biomarker indicating insulin resistance, has yet to be elucidated. Therefore, this study aimed to investigate the association between TyG-BMI index and the risk of OSA using the NHANES database.

Methods

Analyses were performed on NHANES data conducted between 2015 and 2018. Logistic regression, stratified analyses, curve-fitting analyses, and threshold effects analyses were utilized to assess the association between TyG-BMI index and the risk of OSA.

Results

The study included 4,588 participants. Multifactorial logistic regression analyses found a significant association between TyG-BMI and increased risk of OSA [OR: 1.54 (CI:1.39-1.70)]. In stratified analyses, age interacted with the association, with TyG-BMI being associated with increased risk of OSA only in a subgroup of subjects younger than 60 years [1.31 (1.14-1.50)], but gender, smoking status, and alcohol use, did not influence the association. The presence of diabetes, hypertension, and cardiovascular diseases also modified the association, but the number of the included subjects with such conditions was significantly lower, therefore the significance of associations was not observed in those subgroups. Additionally, the risk was non-linearly associated, with the inflection point of TyG-BMI at 12.09, after which the lower slope in the risk was observed.

Conclusion

This study demonstrates that elevated levels of the TyG-BMI index are correlated with risk for OSA, underscoring the significance of these findings in facilitating early prevention or timely intervention for OSA.

Relationships between apolipoprotein E and insulin resistance in patients with obstructive sleep apnoea: a large-scale cross-sectional study

BACKGROUND

Obstructive sleep apnoea (OSA) is commonly associated with insulin resistance (IR) and dyslipidaemia. Apolipoprotein E (APOE) plays important roles in lipid metabolism. The study aimed to disentangle the multifactorial relationships between IR and APOE based on a large-scale population with OSA.

METHODS

A total of 5,591 participants who underwent polysomnography for OSA diagnosis were finally enrolled. We collected anthropometric, fasting biochemical and polysomnographic data for each participant. Linear regression analysis was performed to evaluate the relationships between APOE, IR, and sleep breathing-related parameters. Logistic regression, restricted cubic spline (RCS) and mediation analyses were used to explore relationships between APOE and IR in patients with OSA.

RESULTS

Increasing OSA severity was associated with greater obesity, more obvious dyslipidaemia, and higher levels of APOE and IR. APOE was positively correlated with the apnoea-hypopnoea index (AHI), oxygen desaturation index (ODI) and microarousal index (MAI) even after adjusting for age, sex, body mass index, and smoking and drinking levels (β = 0.107, β = 0.102, β = 0.075, respectively, all P < 0.001). The risks of IR increased from the first to fourth quartiles of APOE (odds ratio (OR) = 1.695, 95% CI: 1.425-2.017; OR = 2.371, 95% confidence interval (CI): 2.009-2.816; OR = 3.392, 95% CI: 2.853-4.032, all P < 0.001) after adjustments. RCS analysis indicated non-linear and dose response relationships between APOE, AHI, ODI, MAI and insulin resistance. Mediation analyses showed that HOMA-IR explained 9.1% and 10% of the association between AHI, ODI and APOE. The same trends were observed in men, but not in women.

CONCLUSIONS

This study showed that APOE is a risk factor for IR; moreover, IR acts as a mediator between OSA and APOE in men. APOE, IR, and OSA showed non-linear and multistage relationships. Taken together, these observations revealed the complex relationships of metabolic disorders in patients with OSA, which could lead to the development of new treatment modalities and a deeper understanding of the systemic impact of OSA.

Association between non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) and sleep disorders in US adults: NHANES 2005 to 2016

NHHR (non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio) is a novel lipid parameter. However, the association between NHHR and sleep disorders remains unknown.; A cross-sectional analysis was conducted using data from the National Health and Nutrition Examination Survey (NHANES) 2005 to 2016. The association between NHHR and sleep disorders was explored using weighted multivariate logistic regression and generalized summation models. Subgroup analyses were employed to verify the robustness of this association. The prevalence of sleep disorders was 25.83% in a total of 22,221 participants. Compared to the lowest quartile of NHHR, participants in the top quartile had a 14% higher odds of sleep disorders prevalence in fully adjusted model (OR: 1.14, 95% CI: 1.06-1.23). After subgroup analyses and interaction tests, sex, race, marital status, education level, body mass index (BMI), person income ratio (PIR), alcohol consumption, smoking status, hypertension, and diabetes mellitus were not significantly associated with this positive association (P for interaction > 0.05). The NHHR is positively associated with sleep disorders in US adults. The management and monitoring of NHHR may have a potential role in improving sleep disorders.

Independent relationship between sleep apnea-specific hypoxic burden and glucolipid metabolism disorder: a cross-sectional study

OBJECTIVES

Obstructive sleep apnea (OSA) is associated with abnormal glucose and lipid metabolism. However, whether there is an independent association between Sleep Apnea-Specific Hypoxic Burden (SASHB) and glycolipid metabolism disorders in patients with OSA is unknown.

METHODS

We enrolled 2,173 participants with suspected OSA from January 2019 to July 2023 in this study. Polysomnographic variables, biochemical indicators, and physical measurements were collected from each participant. Multiple linear regression analyses were used to evaluate independent associations between SASHB, AHI, CT90 and glucose as well as lipid profile. Furthermore, logistic regressions were used to determine the odds ratios (ORs) for abnormal glucose and lipid metabolism across various SASHB, AHI, CT90 quartiles.

RESULTS

The SASHB was independently associated with fasting blood glucose (FBG) (β = 0.058, P = 0.016), fasting insulin (FIN) (β = 0.073, P < 0.001), homeostasis model assessment of insulin resistance (HOMA-IR) (β = 0.058, P = 0.011), total cholesterol (TC) (β = 0.100, P < 0.001), total triglycerides (TG) (β = 0.063, P = 0.011), low-density lipoprotein cholesterol (LDL-C) (β = 0.075, P = 0.003), apolipoprotein A-I (apoA-I) (β = 0.051, P = 0.049), apolipoprotein B (apoB) (β = 0.136, P < 0.001), apolipoprotein E (apoE) (β = 0.088, P < 0.001) after adjustments for confounding factors. Furthermore, the ORs for hyperinsulinemia across the higher SASHB quartiles were 1.527, 1.545, and 2.024 respectively, compared with the lowest quartile (P < 0.001 for a linear trend); the ORs for hyper-total cholesterolemia across the higher SASHB quartiles were 1.762, 1.998, and 2.708, compared with the lowest quartile (P < 0.001 for a linear trend) and the ORs for hyper-LDL cholesterolemia across the higher SASHB quartiles were 1.663, 1.695, and 2.316, compared with the lowest quartile (P < 0.001 for a linear trend). Notably, the ORs for hyper-triglyceridemia{1.471, 1.773, 2.099} and abnormal HOMA-IR{1.510, 1.492, 1.937} maintained a consistent trend across the SASHB quartiles.

CONCLUSIONS

We found SASHB was independently associated with hyperinsulinemia, abnormal HOMA-IR, hyper-total cholesterolemia, hyper-triglyceridemia and hyper-LDL cholesterolemia in Chinese Han population. Further prospective studies are needed to confirm that SASHB can be used as a predictor of abnormal glycolipid metabolism disorders in patients with OSA.

TRIAL REGISTRATION

ChiCTR1900025714 { http://www.chictr.org.cn/ }; Prospectively registered on 6 September 2019; China.

Non-Linear Association between Obstructive Sleep Apnea Risk and Lipid Profile: Data from the 2015-2018 National Health and Nutrition Examination Survey

Background

The relationship between the multivariable apnea prediction (MAP) index and lipid levels was examined using a cross-sectional and retrospective study of National Health and Nutrition Examination Surveys (2015-2018). A total of 3195 participants with MAP scores were included in the analysis.

Methods

The MAP index, an algorithm leveraging sleep apnea symptom frequency, body mass index (BMI), age, and sex, estimates the risk of obstructive sleep apnea (OSA). We investigated the associations between the MAP index and lipid profiles-specifically, high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG) -using weighted linear regression and restricted cubic splines (RCS) analysis. Additionally, mediation analysis was conducted to explore the potential mediating role of physical activity on the link between OSA risk, hyperlipidemia, and cardiovascular mortality.

Results

A non-linear relationship was observed between OSA severity and lipid profiles, including elevated levels of TC, increased LDL-C, higher TG, and decreased HDL-C (All p for non-linearity < 0.05). The findings remained consistent across the stratified sensitivity analyses. Furthermore, physical activity served as a mediator in the association between the MAP index and both hyperlipidemia and cardiovascular mortality, accounting for 16.6% and 16.7% of the indirect effects, respectively.

Conclusions

Participants at high risk for OSA demonstrated an increased prevalence of dyslipidemia. Additionally, engagement in physical activity was shown to have beneficial effects on lipid metabolism.

Correlation between serum leptin level and sleep monitoring indexes in patients with obstructive sleep apnea hypopnea syndrome and its predictive value: a cross-sectional analysis

Objective

To investigate the association between serum leptin (LP) level and polysomnography (PSG) parameters in patients with obstructive sleep apnea hypopnea syndrome (OSAHS).

Methods

A cross-sectional study was conducted. The data of subjects who underwent PSG at hospital between January 2021 and December 2022 were collected retrospectively, 220 participants were included. The subjects were categorized into simple snoring group (n = 45), mild OSAHS group (n = 63), moderate OSAHS group (n = 52), and severe OSAHS group (n = 60). The general characteristics, PSG indices, and serological indices were collected retrospectively. Pearson correlation analysis was used to observe the correlation between serum LP level and PSG parameters. The value of serum LP level in predicting OSAHS was analyzed by receiver operating characteristic curve.

Results

The serum LP level was positively correlated with micro-arousal count, micro-arousal index (MAI), high apnea hypopnea index, times of blood oxygen decreased by≥3% and time in saturation lower 90%, and negatively correlated with lowest nocturnal oxygen saturation and mean oxygen saturation (p < 0.05). The area under the curve (AUC) of serum LP level in predicting the occurrence of OSAHS was 0.8276 (95% CI: 0.7713-0.8839), and when the Youden index was 0.587, the sensitivity was 72.00%, and the specificity was 86.67% (p < 0.0001). In the population with high MAI, the AUC of serum LP level in predicting the occurrence of OSAHS was 0.8825 (95% CI: 0.7833-0.9817), and when the Youden index was 0.690, the sensitivity was 79.00% and the specificity was 90.00% (p < 0.0001).

Conclusion

Serum LP level is associated with the severity of OSAHS. Serum LP level demonstrates a strong predictive value for the occurrence of OSAHS, particularly in population with high MAI.

Association between obstructive sleep apnea and visceral adiposity index and lipid accumulation product: NHANES 2015-2018

BACKGROUND

Obesity refers to a significant contributor to the development of obstructive sleep apnea (OSA). Early prediction of OSA usually leads to better treatment outcomes, and this study aims to employ novel metabolic markers, visceral adiposity index (VAI), and lipid accumulation product (LAP) to evaluate the relationship to OSA.

METHODS

The data used in the current cross-sectional investigation are from the National Health and Nutrition Examination Survey (NHANES), which was carried out between 2015 and 2018. To examine the correlation between LAP and VAI levels and OSA, multivariate logistic regression analysis was adopted. In addition, various analytical methods were applied, including subgroup analysis, smooth curve fitting, and threshold effect analysis.

RESULTS

Among totally 3932 participants, 1934 were included in the OSA group. The median (Q1-Q3) values of LAP and VAI for the participants were 40.25 (21.51-68.26) and 1.27 (0.75-2.21), respectively. Logistic regression studies indicated a positive correlation between LAP, VAI, and OSA risk after adjusting for potential confounding variables. Subgroup analysis revealed a stronger correlation between LAP, VAI levels, and OSA among individuals aged < 60 years. Through smooth curve fitting, specific saturation effects of LAP, VAI, and BMD were identified, with inflection points at 65.684 and 0.428, respectively.

CONCLUSION

This study demonstrates that elevated levels of LAP and VAI increase the risk of OSA, suggesting their potential as predictive markers for OSA and advocating for dietary and exercise interventions to mitigate OSA risk in individuals with high LAP and VAI levels.

Evaluate the Relationship Between Obstructive Sleep Apnea and Metabolic Syndrome in Real-World Data

Objective

Obstructive sleep apnea (OSA) is a disorder characterized by disruption in breathing and hypoventilation. In parallel, metabolic syndrome (MetS) mainly co-occur with OSA, however, their association has not been fully elucidated. Therefore, this study aimed to reveal the relationship between OSA and MetS using data from the National Health And Nutrition Examination Survey (NHANES) database and pooled data from Genome-Wide Association Studies (GWAS).

Material and Methods

Data from the National Health and Nutrition Examination Survey and pooled data from genome-wide association analysis (GWAS) were used univariate and multivariate logistic regression analyses were carried out to evaluate the correlation between OSA and MetS, and multivariate logistic regression models were utilized for adjusting for potential confounders. Two-sample Mendelian randomization (MR) was used to assess the causal relationship between OSA and MetS. The variance-weighted inverse method was employed as the main method of analysis.

Results

A positive relationship of OSA with Mets was evidenced by multivariate logistic regression analysis, and OSA was associated with higher incidence rates of all-cause and cardiovascular mortality. OSA is strongly associated with abdominal obesity, hypertension, hyperglycemia, high triglycerides, and low HDL. Furthermore, except for hypertriglyceridemia, MR analysis indicated that genetically driven OSA was causally associated with a higher risk of MetS.

Conclusion

The positive relationship of OSA with Mets was revealed, and higher incidence rates of all-cause mortality and cardiovascular mortality were noted to be correlated with OSA. MR analysis further confirmed the causal relationship of OSA with MetS and cardiovascular disease.

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

Background

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

Methods

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

Results

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

Conclusion

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

[Diabetes and obstructive sleep apnoea: A case-control study]

INTRODUCTION

Obstructive sleep apnoea (OSA) and diabetes mellitus (DM) are very prevalent diseases frequently associated. Their coexistence is independently associated with an increased prevalence of cardiovascular comorbidities. As this association is underdiagnosed, it is necessary to optimise clinical suspicion by studying independent predictors of DM or prediabetes (preDM) in patients with OSA.

METHOD

A simple randomised case-control study, matched for sex, body mass index (BMI) and age, aimed to study the association of OSA with DM and preDM and to identify independent predictors for both diseases in people with OSA.

RESULTS

We included 208 cases with OSA and 208 controls without OSA. In the former, 18.8% had DM compared to only 10.1% in the latter (P=.00). Prevalence of preDM was 41.8% vs. 10.6%, respectively (P=.00). One hundred and twenty-four cases (59.6%) reported excessive daytime sleepiness (EDS) (Epworth scale, 10.5±3.1) vs. 24.5% of the control group (Epworth scale, 6.6±2.9). Apnoea-hypopnoea index (AHI) and O2 desaturation indices (IDO, CT90 and CT80) were significantly higher in the case group. The risk of MD was related to age, nocturnal hypoxaemia and EDS. The risk of pre-MD was related to BMI and AHI.

CONCLUSIONS

OSA is associated with DM and preDM. Age, nocturnal hypoxaemia and EDS are predictors of DM. BMI and AHI are predictors of pre-MD.

The Role of the Circadian Rhythm in Dyslipidaemia and Vascular Inflammation Leading to Atherosclerosis

Cardiovascular diseases (CVD) are among the leading causes of death worldwide. Many lines of evidence suggest that the disturbances in circadian rhythm are responsible for the development of CVDs; however, circadian misalignment is not yet a treatable trait in clinical practice. The circadian rhythm is controlled by the central clock located in the suprachiasmatic nucleus and clock genes (molecular clock) located in all cells. Dyslipidaemia and vascular inflammation are two hallmarks of atherosclerosis and numerous experimental studies conclude that they are under direct influence by both central and molecular clocks. This review will summarise the results of experimental studies on lipid metabolism, vascular inflammation and circadian rhythm, and translate them into the pathophysiology of atherosclerosis and cardiovascular disease. We discuss the effect of time-respected administration of medications in cardiovascular medicine. We review the evidence on the effect of bright light and melatonin on cardiovascular health, lipid metabolism and vascular inflammation. Finally, we suggest an agenda for future research and recommend on clinical practice.

Time Spent with Saturation below 80% versus 90% in Patients with Obstructive Sleep Apnoea

BACKGROUND

Nocturnal hypoxaemia measured as the percentage of total sleep time spent with saturation below 90% (TST90%) may better predict cardiovascular consequences of obstructive sleep apnoea (OSA) than the number of obstructive respiratory events measured with the apnoea-hypopnea index (AHI). Deeper hypoxaemia may potentially induce more severe pathophysiological consequences. However, the additional value of the percentage of total sleep time spent with saturation below 80% (TST80%) to TST90% is not fully explored.

METHODS

Comprehensive medical history was taken and fasting lipid and C-reactive protein levels were measured in 797 volunteers participating in two cohort studies in Hungary and Romania. Sleep parameters, including AHI, TST90% and TST80%, were recorded following a polysomnography (PSG, n = 598) or an inpatient cardiorespiratory polygraphy (n = 199). The performance of TST80% to predict cardiovascular risk was compared with TST90% using linear and logistic regression analyses as well receiver operating characteristics curves. Sensitivity analyses were performed in patients who had PSG, separately.

RESULTS

Both parameters are significantly related to cardiovascular risk factors; however, TST80% did not show better predictive value for cardiovascular risk than TST90%. On the other hand, patients with more severe hypoxaemia reported more excessive daytime sleepiness.

CONCLUSIONS

TST80% has limited additional clinical value compared to TST90% when evaluating cardiovascular risk in patients with OSA.

A narrative review of the mechanisms and consequences of intermittent hypoxia and the role of advanced analytic techniques in pediatric autonomic disorders

Disorders of autonomic functions are typically characterized by disturbances in multiple organ systems. These disturbances are often comorbidities of common and rare diseases, such as epilepsy, sleep apnea, Rett syndrome, congenital heart disease or mitochondrial diseases. Characteristic of many autonomic disorders is the association with intermittent hypoxia and oxidative stress, which can cause or exaggerate a variety of other autonomic dysfunctions, making the treatment and management of these syndromes very complex. In this review we discuss the cellular mechanisms by which intermittent hypoxia can trigger a cascade of molecular, cellular and network events that result in the dysregulation of multiple organ systems. We also describe the importance of computational approaches, artificial intelligence and the analysis of big data to better characterize and recognize the interconnectedness of the various autonomic and non-autonomic symptoms. These techniques can lead to a better understanding of the progression of autonomic disorders, ultimately resulting in better care and management.

En Route to Personalised Medicine in Obstructive Sleep Apnoea

Obstructive sleep apnoea (OSA) is a common disorder that can cause night- and daytime symptoms and impair driving and work performance [...].

Differences in Long-Term Heart Rate Variability between Subjects with and without Metabolic Syndrome: A Systematic Review and Meta-Analysis

BACKGROUND

Our aim was to determine the impact that metabolic syndrome (MS) produces in long-term heart rate variability (HRV), quantitatively synthesizing the results of published studies to characterize the cardiac autonomic dysfunction in MS.

METHODS

We searched electronic databases for original research works with long-term HRV recordings (24 h) that compared people with MS (MS+) versus healthy people as a control group (MS-). This systematic review and meta-analysis (MA) was performed according to PRISMA guidelines and registered at PROSPERO (CRD42022358975).

RESULTS

A total of 13 articles were included in the qualitative synthesis, and 7 of them met the required criteria to be included in the MA. SDNN (-0.33 [-0.57, 0.09], p = 0.008), LF (-0.32 [-0.41, -0.23], p < 0.00001), VLF (-0.21 [-0.31, -0.10], p = 0.0001) and TP (-0.20 [-0.33, -0.07], p = 0.002) decreased in patients with MS. The rMSSD (p = 0.41), HF (p = 0.06) and LF/HF ratio (p = 0.64) were not modified.

CONCLUSIONS

In long-term recordings (24 h), SDNN, LF, VLF and TP were consistently decreased in patients with MS. Other parameters that could be included in the quantitative analysis were not modified in MS+ patients (rMSSD, HF, ratio LF/HF). Regarding non-linear analyses, the results are not conclusive due to the low number of datasets found, which prevented us from conducting an MA.

Investigating the Relationship between Obstructive Sleep Apnoea, Inflammation and Cardio-Metabolic Diseases

Obstructive sleep apnoea (OSA) is a prevalent underdiagnosed disorder whose incidence increases with age and weight. Uniquely characterised by frequent breathing interruptions during sleep-known as intermittent hypoxia (IH)-OSA disrupts the circadian rhythm. Patients with OSA have repeated episodes of hypoxia and reoxygenation, leading to systemic consequences. OSA consequences range from apparent symptoms like excessive daytime sleepiness, neurocognitive deterioration and decreased quality of life to pathological complications characterised by elevated biomarkers linked to endocrine-metabolic and cardiovascular changes. OSA is a well-recognized risk factor for cardiovascular and cerebrovascular diseases. Furthermore, OSA is linked to other conditions that worsen cardiovascular outcomes, such as obesity. The relationship between OSA and obesity is complex and reciprocal, involving interaction between biological and lifestyle factors. The pathogenesis of both OSA and obesity involve oxidative stress, inflammation and metabolic dysregulation. The current medical practice uses continuous positive airway pressure (CPAP) as the gold standard tool to manage OSA. It has been shown to improve symptoms and cardiac function, reduce cardiovascular risk and normalise biomarkers. Nonetheless, a full understanding of the factors involved in the deleterious effects of OSA and the best methods to eliminate their occurrence are still poorly understood. In this review, we present the factors and evidence linking OSA to increased risk of cardiovascular conditions.

Association between glycolipids and risk of obstructive sleep apnea: A population-based study

Background

This study aimed to investigate the associations between multiple glycolipid biomarkers and the risk of obstructive sleep apnea (OSA).

Methods

Participants (10,286) aged from 35 to 74 years old were included in this cross-sectional study from the baseline survey of the Guangzhou Heart Study. OSA was ascertained using both Berlin Questionnaire and STOP-BANG Questionnaire. Fasting blood samples were collected from each participant; fasting blood glucose (FBG) and serum concentrations of high-density lipoprotein cholesterol (HDL-CH), low-density lipoprotein cholesterol (LDL-CH), total cholesterol (TC), and triglyceride (TG) were determined. Odds ratio (OR) with 95% confidence interval (CI) was calculated using the multivariate logistic regression model after adjustment for covariates.

Results

Of the participants included, 15.56% were categorized into the pre-OSA group, and 8.22% into the OSA group. When comparing the highest with the lowest quartiles, HDL-HC was associated with a 22% (OR: 0.78, 95% CI: 0.65–0.94) and 41% (OR: 0.59, 95% CI: 0.45–0.78) reduced risk of pre-OSA and OSA, triglyceride was associated with a 32% (OR 1.32, 95% CI 1.08–1.60) and a 56% (OR 1.56, 95% CI 1.18–2.07) increased risk of pre-OSA and OSA, and FBG was associated with a 1.37-fold (95% CI 1.13–1.67) risk of pre-OSA and 1.38-fold (95% CI 1.03–1.85) risk of OSA. A significant exposure-response trend was observed for HDL-HC, TG, and FBG with both OSA and Pre-OSA (all p &lt; 0.05). No significant association of LDL-CH and TC with the risk of both pre-OSA and OSA was observed.

Conclusion

The findings suggest that serum HDL-CH was inversely associated with OSA risk, while elevated serum TG and FBG could increase the risk of OSA. Healthy glycolipid metabolism warrants more attention in the field of OSA prevention.

Lipoprotein Subfractions Associated with Endothelial Function in Previously Healthy Subjects with Newly Diagnosed Sleep Apnea-A Pilot Study

BACKGROUND

Obstructive sleep apnea (OSA) activates several pathophysiological mechanisms which can lead to the development of vascular diseases. Endothelial dysfunction (ED) is an initial step in the development of atherosclerosis. The association between ED and OSA has been described in several studies, even in previously healthy subjects. High-density lipoproteins (HDL) were generally considered to be atheroprotective, and low-density lipoprotein (LDL) to be an atherogenic component of lipoproteins. However, recent findings suggest a pro-atherogenic role of small HDL subfractions (8-10) and LDL subfractions (3-7). This study aimed to evaluate the relationship between endothelial function and lipid subfractions in previously healthy OSA subjects.

MATERIAL AND METHODS

We prospectively enrolled 205 subjects with sleep monitoring. Plasma levels of triacylglycerols, total cholesterol, LDL, HDL, and their subfractions were assessed. Endothelial function was determined using peripheral arterial tonometry, and reperfusion hyperemia index (RHI) was assessed.

RESULTS

Plasma levels of small and intermediate HDL subfractions have statistically significant pro-atherogenic correlations with endothelial function (p = 0.015 and p = 0.019). In other lipoprotein levels, no other significant correlation was found with RHI. In stepwise multiple linear regression analysis, small HDL (beta = -0.507, p = 0.032) was the only significant contributor in the model predicting RHI.

CONCLUSIONS

In our studied sample, a pro-atherogenic role of small HDL subfractions in previously healthy subjects with moderate-to-severe OSA was proven.