Relationship Between OSA and Hypertension

Daytime Somnolence and Sleep Apnea Are Associated With Dizziness in the Elderly

OBJECTIVE

Dizziness is a debilitating multifactorial disorder commonly affecting the elderly. Daytime somnolence and sleep apnea have been linked to dizziness, but previous studies were limited by small sample sizes. The purpose of this study was to examine the relationship between dizziness and daytime somnolence and sleep-disordered breathing, in a nationally representative sample of elderly adults, while adjusting for possible confounders and mediators.

STUDY DESIGN

Data from the National Health and Nutrition Examination Study (NHANES; 2017-2020 prepandemic data) were analyzed in a cross-sectional manner using survey methods.

SETTING

Community-based setting in the United States.

PARTICIPANTS

A total of 1,490 nationally representative participants aged ≥70 years.

MAIN OUTCOMES

Multivariable logistic regression was used to examine the relationship between dizziness and daytime somnolence, snoring, and apnea, while adjusting for covariates (gender, age, body mass index, and various medical conditions that may confound this relationship).

RESULTS

Frequent daytime somnolence five or more times monthly (odds ratio, 2.13; 95% confidence interval, 1.49-3.06) and presence of apnea (odds ratio, 1.65; 95% confidence interval, 1.20-2.27) were found to be associated with greater odds of dizziness when adjusting for medical comorbidities. A significant association was not found between snoring and dizziness.

CONCLUSIONS AND RELEVANCE

In the elderly, daytime somnolence and apnea were independently associated with increased odds of dizziness, even after adjusting for medical comorbidities. Daytime somnolence and sleep apnea should be added to the differential diagnosis in this patient population. Optimizing sleep may help reduce symptoms of dizziness in this population, but prospective studies would be required to confirm these findings.Level of evidence: 4.

Sleep Disordered Breathing and Neurocognitive Disorders

Sleep-disordered breathing (SDB), which includes conditions such as obstructive sleep apnea (OSA) and central sleep apnea (CSA), is an independent risk factor for cerebral small vessel disease (CSVD), stroke, heart failure, arrhythmias, and other cardiovascular disorders. The influence of OSA on brain structure and cognitive function has become an essential focus in the heart-brain axis, given its potential role in developing neurocognitive abnormalities. In this review, we found that OSA plays a significant role in the cardio-neural pathway that leads to the development of cerebral small vessel disease and neurocognitive decline. Although data is still limited on this topic, understanding the critical role of OSA in the heart-brain axis could lead to the utilization of imaging modalities to simultaneously identify early signs of pathology in both organ systems based on the known OSA-driven pathological pathways that result in a disease state in both the cardiovascular and cerebrovascular systems. This narrative review aims to summarize the current link between OSA and neurocognitive disorders, cardio-neural pathophysiology, and the treatment options available for patients with OSA-related neurocognitive disorders.

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.

Screening Tools for Obstructive Sleep Apnea in Pregnant Women: An Extended and Updated Systematic Review and Meta-analysis

The prevalence of obstructive sleep apnea syndrome (OSA) increases in women during pregnancy and negatively affects maternal and fetal outcomes. The updated systematic review and meta-analysis aimed to evaluate the validity of the Berlin, STOP-Bang, and Epworth sleepiness scale (ESS) questionnaires in detecting OSA in pregnant women. PubMed, Embase, and Web of Science were searched systematically up to March 2022. After eligible studies inclusion, two independent reviewers extracted demographic and clinical data. Bivariate random effects models were used to estimate the pooled accuracy measures including sensitivity and specificity, positive (PPV) and negative predictive values (NPVs), diagnostic odds ratio (DOR), and receiver operating characteristic curve (ROC) curve. We included 8 studies including 710 pregnant women with suspected OSA. The performance values of Berlin, STOP-Bang, and ESS questionnaires were as follows: the pooled sensitivity were 61% (95% confidence interval (CI): 40%-80%), 59% (95% CI: 49%-69%), and 29%, (95% CI: 10%-60%); pooled specificity were 61% (95% CI: 42%-78%), 80% (95% CI: 55%-93%), and 80% (95% CI: 50%-94%); pooled PPVs were 60% (95% CI: 0.49-0.72), 73% (95% CI: 61%-85%), and 59% (95% CI: 31%-87%); pooled NPVs were 60% (95% CI: 0.49-0.71), 65% (95% CI: 54%-76%), and 53% (95% CI: 41%-64%); and pooled DORs were 3 (95% CI: 1-5), 6 (95% CI: 2-19), and 2 (95% CI: 1-3), respectively. It seems that the Berlin, STOP-Bang, and ESS questionnaires had poor to moderate sensitivity and specificity in pregnancy, with the ESS showing the worst characteristics. Further studies are required to evaluate the performance of alternative screening methods for OSA in pregnancy.

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.

Advancements in the neurocirculatory reflex response to hypoxia

Hypoxia is a pivotal factor in the pathophysiology of various clinical conditions, including obstructive sleep apnea, which has a strong association with cardiovascular diseases like hypertension, posing significant health risks. Although the precise mechanisms linking hypoxemia-associated clinical conditions with hypertension remains incompletely understood, compelling evidence suggests that hypoxia induces plasticity of the neurocirculatory control system. Despite variations in experimental designs and the severity, frequency, and duration of hypoxia exposure, evidence from animal and human models consistently demonstrates the robust effects of hypoxemia in triggering reflex-mediated sympathetic activation. Both acute and chronic hypoxia alters neurocirculatory regulation and, in some circumstances, leads to sympathetic outflow and elevated blood pressures that persist beyond the hypoxic stimulus. Dysregulation of autonomic control could lead to adverse cardiovascular outcomes and increase the risk of developing hypertension.

Sympathetic overactivity and nocturnal diuresis in obstructive sleep apnea alter the response to hypertension therapy

BACKGROUND

Obstructive sleep apnea (OSA) is associated with high blood pressure that responds poorly to usual antihypertensive therapy.

METHODS AND RESULTS

Forty-one subjects with OSA had 25% higher plasma norepinephrine and 42% higher epinephrine measured every 2 h over 24 h than 20 control subjects. They also excreted more sodium during sleep. This suggested that that a sympatholytic would be a more successful antihypertensive than a diuretic. To test this hypothesis we treated a second group of 23 hypertensive apneics with placebo, 6 weeks of the sympatholytic guanfacine and 6 weeks of hydrochlorothiazide in a crossover study. Guanfacine lowered 24-hour blood pressure by 9.6/6.7 mmHg, more than the 5.4/2.9 mmHg effect of hydrochlorothiazide (P < 0.05). Nighttime systolic blood pressure dipping was poor at 6.6 ± 1.8%. Hydrochlorothiazide did not alter blood pressure dipping but guanfacine improved dipping to 9.1 ± 1.2%, a better result (P = 0.03) than from the diuretic. Central aortic pressure by pulse wave analysis was 120/84 mmHg on hydrochlorothiazide and 109/72 on guanfacine, (P < 0.05). Guanfacine, but not hydrochlorothiazide, improved baroreflex sensitivity, heart rate variability and flow mediated vascular dilation, suggesting that decreasing the elevated sympathetic nerve activity of obstructive sleep apnea returned vascular function toward normal.

CONCLUSIONS

OSA is the most common condition associated with antihypertensive treatment failure. It increased sympathetic nerve activity day and night. Drugs that block sympathetic nerve function are not among the 4 most commonly recommended classes of antihypertensives but diuretics are. Sympatholytic therapy was superior to diuretic treatment for hypertension associated with sleep apnea.

TRIAL REGISTRATION

NCT, NCT02699125, Registered 26 February 2016 - Retrospectively registered, https://clinicaltrials.gov/study/NCT02699125 .

The effects of obstructive sleep apnea on blood pressure variability and load in patients with hypertension

BACKGROUND

Hypertension frequently coexists with obstructive sleep apnea (OSA), and their interplay substantially impacts the prognosis of affected individuals. Investigating the influence of OSA on blood pressure variability (BPV) and blood pressure load (BPL) in hypertensive patients has become a focal point of clinical research.

METHODS

This cross-sectional study recruited hypertensive patients (n = 265) without discrimination and classified them into four groups based on their apnea-hypopnea index (AHI): control group (n = 40), AHI < 5; mild group (n = 74), 5 ≤ AHI ≤ 15; moderate group (n = 68), 15 < AHI ≤ 30; severe group (n = 83), AHI > 30. All participants underwent comprehensive assessments, including polysomnography (PSG) monitoring, 24-h ambulatory blood pressure (ABP) monitoring, cardiac Doppler ultrasound, and additional examinations when indicated.

RESULTS

BPV and BPL exhibited significant elevations in the moderate and severe OSA groups compared to the control and mild OSA groups (P < 0.05). Moreover, interventricular septum thickness and left ventricular end-diastolic volume (LVEDV) demonstrated higher values in the moderate and severe OSA groups (P < 0.05). Multiple stepwise regression analysis identified noteworthy risk factors for elevated BPV in hypertensive patients with OSA, including AHI, maximum apnea time, total times of oxygen reduction, and mean time of apnea.

CONCLUSION

Hypertensive patients with moderate to severe OSA exhibited substantially increased BPV and BPL. Moreover, BPV was correlated with AHI, maximum apnea time, total times of oxygen reduction, and mean time of apnea in hypertensive patients with OSA.

A risk prediction nomogram for resistant hypertension in patients with obstructive sleep apnea

Patients with obstructive sleep apnea (OSA) are liable to have resistant hypertension (RH) associated with unfavorable cardiovascular events. It is of necessity to predict OSA patients who are susceptible to resistant hypertension. Hence, we conducted a retrospective study based on the clinical records of OSA patients admitted to Yixing Hospital Affiliated to Jiangsu University from January 2018 to December 2022. According to different time periods, patients diagnosed between January 2018 and December 2021 were included in the training set (n = 539) for modeling, and those diagnosed between January 2022 and December 2022 were enrolled into the validation set (n = 259) for further assessment. The incidence of RH in the training set and external validation set was comparable (P = 0.396). The related clinical data of patients enrolled were collected and analyzed through univariate analysis and least absolute shrinkage and selection operator (LASSO) logistic regression analysis to identify independent risk factors and construct a nomogram. Finally, five variables were confirmed as independent risk factors for OSA patients with RH, including smoking, heart disease, neck circumference, AHI and T90. The nomogram established on the basis of variables above was shown to have good discrimination and calibration in both the training set and validation set. Decision curve analysis indicated that the nomogram was useful for a majority of OSA patients. Therefore, our nomogram might be useful to identify OSA patients at high risk of developing RH and facilitate the individualized management of OSA patients in clinical practice.

Successful Virtual CPAP Set up in Obstructive Sleep Apnoea: A positive innovation during the pandemic

BACKGROUND

Traditionally continuous positive airways pressure (CPAP) trials for obstructive sleep apnoea (OSA) are through face to face (F2F) set up. During Covid-19 pandemic CPAP was classed as aerosol-generating hence Leeds sleep service moved to a virtual service. Patients received equipment by post followed by virtual reviews (VR). We evaluated the adherence and symptomatic benefit of postal compared to F2F method.

METHODS

Observational data were collected from databases monitoring CPAP loans. F2F patients met a sleep technician for hands on setup in 2019, and in 2020 postal patients received equipment, written guides, and links to custom made YouTube videos. All (F2F and postal) patients had a telephone and VR appointment to discuss symptoms, and CPAP machine (AirSense 10, ResMed Inc., San Diego, USA) data including data on usage and treatment apnoea-hypopnoea index (AHI). Data was analysed using unpaired T-tests, Mann-Whitney U tests, and chi-square tests to examine differences in means, medians, and proportions, respectively of the F2F and postal groups.

RESULTS

Both groups (n = 1,221, 656 F2F, 53.7%) were similar in all categories except length of CPAP trial (postal 33 vs F2F 84 days,p < 0.0001), change in AHI (postal 22.4/Hr vs F2F 25.1/Hr,p = 0.04), and trial average use (postal 4.9 vs F2F 5.2 h,p = 0.04). There was no significant difference in the proportion of patients continuing with CPAP (postal 64%, F2F 66%, p = 0.71), the improvement in Epworth Sleepiness Score (ESS) (postal 6.9/24, F2F 7.1/24, p = 0.31) or the patient's subjective rating on whether they felt much better, better, the same or worse on CPAP (p = 0.27). Logistic regression showed factors which affected odds ratios of continuing CPAP were diagnostic AHI, treatment AHI, treatment ESS and how they felt on CPAP. Trial type did not affect the odds ratios of continuing CPAP.

CONCLUSIONS

Postal CPAP trial patients had similar odds of continuing CPAP therapy compared to patients with F2F trials and achieved similar levels of ESS improvement and reporting feeling better on CPAP. This provides support for postal trials as a viable option post-pandemic.

The role of renal denervation in cardiology and beyond: An updated comprehensive review and future directives

Renal denervation (RDN) is a minimally invasive intervention performed by denervation of the nervous fibers in the renal plexus, which decreases sympathetic activity. These sympathetic nerves influence various physiological functions that regulate blood pressure (BP), including intravascular volume, electrolyte composition, and vascular tone. Although proven effective in some trials, controversial trials, such as the Controlled Trial of Renal Denervation for Resistant Hypertension (SYMPLICITY-HTN3), have demonstrated contradictory results for the effectiveness of RDN in resistant hypertension (HTN). In the treatment of HTN, individuals with primary HTN are expected to experience greater benefits compared to those with secondary HTN due to the diverse underlying causes of secondary HTN. Beyond its application for HTN, RDN has also found utility in addressing cardiac arrhythmias, such as atrial fibrillation, and managing cases of heart failure. Non-cardiogenic applications of RDN include reducing the intensity of obstructive sleep apnea (OSA), overcoming insulin resistance, and in chronic kidney disease (CKD) patients. This article aims to provide a comprehensive review of RDN and its uses in cardiology and beyond, along with providing future directions and perspectives.

Associations Between Sleep Spindle Metrics, Age, Education and Executive Function in Young Adult and Middle-Aged Patients with Obstructive Sleep Apnea

Purpose

This study aimed to investigate the association between sleep spindle metrics and executive function in individuals with obstructive sleep apnea (OSA). Furthermore, we examined the association of age and education on executive function.

Patients and Methods

A total of 230 (40.90 ± 8.83 years, F/M = 45/185) participants were enrolled. Overnight electroencephalogram (C3-M2) recording detected sleep spindles by a novel U-Net-type neural network that integrates temporal information with time-frequency images. Sleep spindle metrics, including frequency (Hz), overall density (events/min), fast density (events/min), slow density (events/min), duration (sec) and amplitude (µV), were measured. Executive function was assessed using standardized neuropsychological tests. Associations between sleep spindle metrics, executive function, and demographic factors were analyzed using multivariate linear regression.

Results

In fully adjusted linear regression models, higher overall sleep spindle density (TMT-A, B=-1.279, p=0.009; TMT-B, B=-1.813, p=0.008), fast sleep spindle density (TMT-A, B=-1.542, p=0.048; TMT-B, B=-2.187, p=0.036) and slow sleep spindle density (TMT-A, B=-1.731, p=0.037; TMT-B, B=-2.449, p=0.034) were associated with better executive function. And the sleep spindle duration both during N2 sleep time (TMT-A, B=-13.932, p=0.027; TMT-B, B=-19.001, p=0.034) and N3 sleep time (TMT-B, B=-29.916, p=0.009; Stroop-incongruous, B=-21.303, p=0.035) was independently associated with better executive function in this population. Additionally, age and education were found to be highly associated with executive function.

Conclusion

Specific sleep spindle metrics, higher overall density, fast density and slow density during N2 sleep time, and longer duration during N2 and N3 sleep time, are independent and sensitive indicators of better executive function in young adult and middle-aged patients with OSA. Further research is needed to explore the underlying mechanisms and clinical implications of these findings.

Prognostic implications of obstructive sleep apnea in patients with acute coronary syndrome stratified by homocysteine level: a prospective cohort study

BACKGROUND

Sporadic studies have examined the impact of OSA on ACS patients by homocysteine (Hcy) level. This study attempted to comprehensively evaluate the effects of the interaction between Hcy and OSA on long-term cardiovascular outcomes in ACS patients.

METHODS

In this prospective, large-scale cohort study, 2160 patients admitted for ACS were recruited to undergo overnight sleep monitoring. OSA was diagnosed when apnea-hypopnea index ≥ 15 events/h. Patients with normohomocysteinemia (NHcy) were defined as having serum Hcy ≤ 15 μmol/L, and the others had hyperhomocysteinemia (HHcy). The primary endpoint was major adverse cerebrocardiovascular event (MACCE), a composite of cardiovascular death, myocardial infarction, stroke, ischemia-driven revascularization and hospitalization for unstable angina and heart failure.

RESULTS

A total of 1553 eligible ACS patients (average age: 56.3 ± 10.5 years) were enrolled, among which 819 (52.7%) had OSA, and 988 (63.6%) were with NHcy. OSA did not significantly affect the level of Hcy. During a median follow-up of 2.9 (1.6, 3.5) years, after adjustment for clinical confounders, OSA was associated with increased risk for MACCE occurrence versus non-OSA ones in ACS patients with NHcy (adjusted hazard ratio [HR] = 1.36, 95% confidence interval [CI] 1.02-1.83, P = 0.039), but not in those with HHcy (adjusted HR = 0.92, 95%CI 0.62-1.36, P = 0.668). There was an absence of interaction between homocysteine level and OSA in relation to MACCE (interaction P = 0.106).

CONCLUSIONS

OSA was independently associated with worse prognosis in ACS patients with NHcy. Our study emphasized the necessity to identify potential presence of OSA in such a population.

TRIAL REGISTRATION

ClinicalTrials.gov; Number: NCT03362385; URL: www.

CLINICALTRIALS

gov .

Factors influencing new-onset hypertension in elderly patients with obstructive sleep apnea: A multicenter cohort study

Investigating the influencing factors of new-onset hypertension in the elderly with obstructive sleep apnea (OSA). 450 Chinese older patients with OSA who were non-hypertensive at baseline were enrolled. All patients had undergone polysomnography monitoring in the multicenter study. The primary endpoint was incident hypertension. Kaplan-Meier survival analysis was performed, and multivariate Cox proportional hazards models were generated to determine the factors influencing new-onset hypertension. A total of 176 (39.1%) patients developed hypertension. The hypertension group had older age, higher hemoglobin (Hb) level and apnea-hypopnea index (AHI) values than the non-hypertension group (all p < 0.05). During the median 33-month follow-up period, multivariate Cox analysis showed age (hazard ratio (HR) = 1.039, 95% confidence interval (95% CI): 1.016-1.062), AHI (HR = 1.015, 95% CI: 1.007-1.023) and Hb level (HR = 1.016, 95% CI: 1.008-1.025) were independent predictors of new-onset hypertension. However, continuous positive airway pressure (CPAP; HR = 0.508, 95% CI: 0.271-0.951) reduced the risk of developing hypertension. Notably, the subgroup analysis demonstrated that the plasma glucose level (HR = 1.168, 95% CI: 1.029-1.326) was a risk factor for male patients. Besides length of time with the pulse oxygen saturation less than 90% (Tsat90; HR = 1.005, 95% CI: 1.003-1.007), body mass index (BMI; HR = 1.170, 95% CI: 1.043-1.311), and dyslipidemia (HR = 2.335, 95% CI: 1.144-4.766) had statistically significant effects on the incidence of hypertension in certain subgroups. Although this study lacked analysis of items such as living habits and medication, it did show age, AHI, Hb and CPAP affected the development of hypertension in elderly OSA patients. These findings suggested that targeted interventions in specific populations may be more effective in preventing hypertension.

Cardiovascular Disease Outcomes Associated with Obstructive Sleep Apnea in Diabetics: A Systematic Review and Meta-Analysis

BACKGROUND

There is significant pathogenic and epidemiological overlap between diabetes and obstructive sleep apnea (OSA). This systematic review aimed to ascertain the association between OSA and cardiovascular disease (CVD) in a diabetic population.

METHODS

The study protocol was registered with PROSPERO (CRD42023404126). On 15 July 2023, a comprehensive search of the literature was performed in PubMed, EBSCO, Scopus, ProQuest, and Web of Science, using keywords and synonyms of OSA, diabetes, and CVD, coupled with specific terms for different CVDs. Only observational studies that reported CVD events in diabetics (with and without OSA) were included. The quality of the studies included in the analysis was assessed using the Newcastle-Ottawa Scale.

RESULTS

In the primary literature search, 8795 studies were identified, of which 9 met the inclusion criteria and included 17,796 participants. Eight studies were eligible for meta-analysis, and a pooled risk ratio (RR) of 1.29 (95% CI = 0.91-1.83) was found for developing CVD in diabetics with OSA at a 95% prediction interval of 0.30-5.60. The included studies showed significant heterogeneity with an I2 value of 91%.

CONCLUSION

These findings show the possible association between OSA and diabetes and their impact on CVDs. Identifying and managing OSA in individuals with diabetes at an early phase could potentially reduce the risk of CVDs and its related complications.

Clinical considerations and pathophysiological associations among obesity, weight loss, heart failure, and hypertension

PURPOSE OF REVIEW

To describe the relationship between three pandemics: hypertension, obesity, and heart failure. From pathophysiology to treatment, understanding how these disease entities are linked can lead to breakthroughs in their prevention and treatment. The relevance of this review lies in its discussion of novel pharmacological and surgical treatment strategies for obesity and hypertension, and their role in the prevention and treatment of heart failure.

RECENT FINDINGS

Novel medications such as GLP-1 agonists have demonstrated sustained weight loss in patients with obesity, and concurrent improvements in their cardiometabolic profile, and possibly also reductions in hypertension-related comorbidities including heart failure. Surgical therapies including laparoscopic bariatric surgery represent an important treatment strategy in obese patients, and recent studies describe their use even in patients with advanced heart failure, including those with ventricular assist devices.

SUMMARY

These developments have deep implications on our efforts to understand, mitigate, and ultimately prevent the three pandemics, and offer promising improvements to quality of life, survival, and the cost burden of these diseases.

Evaluation of obstructive sleep apnea: an analysis based on aberrant genes

BACKGROUND

Obstructive sleep apnea (OSA) is an upstream disorder that frequently causes multisystem disorders. Much research has revealed the pathogenesis of OSA, but there is still a lack of research on the complications caused by OSA.

METHODS

The mRNA expression and methylation dataset based on peripheral blood mononuclear cells (PBMCs) were downloaded from the Gene Expression Omnibus (GEO) database. All differential expressed genes (DEGs) were ranked using the Robust Rank Aggregation (RRA) algorithm. A weighted gene co-expression network analysis (WGCNA) was constructed. Subsequently, we used immune infiltration, enrichment analysis, and least absolute shrinkage and selection operator (LASSO) regression analysis for apnea and hypopnea index (AHI) and hypertension and excessive daytime sleepiness (EDS) and constructed diagnostic model using random forest algorithm.

RESULTS

In the present study, we identified 318 DEGs in PBMCs involved in pathogenesis or continuous positive airway pressure (CPAP) therapy. Pathway enrichment identified DEGs associated with protein regulation and metabolism. Notably, through intra group analysis, we found that the immune disorder was more significant for OSA in males, non-daytime sleepy, or non-hypertensive OSA. The area under the ROC curve of model for EDS prediction is 0.889 and 0.852 for hypertension. Notably, we found that the diagnostic model had a high linear predictive value for AHI.

CONCLUSIONS

Our results indicate that PBMCs are a significant component of alterations in OSA and are expected to explain the mechanism of multisystem diseases caused by OSA. The present study provides new insights for symptom evaluation, classification and treatment of OSA from the molecular level.

Cost-effectiveness of neuromuscular electrical stimulation for the treatment of mild obstructive sleep apnea: an exploratory analysis

OBJECTIVES

To assess the potential cost-effectiveness of neuromuscular electrical stimulation (NMES) for treatment of mild obstructive sleep apnea (OSA).

METHODS

A decision-analytic Markov model was developed to estimate health state progression, incremental cost, and quality-adjusted life year (QALY) gain of NMES compared to no treatment, continuous airway pressure (CPAP), or oral appliance (OA) treatment. The base case assumed no cardiovascular (CV) benefit for any of the interventions, while potential CV benefit was considered in scenario analyses. Therapy effectiveness was based on a recent multi-center trial for NMES, and on the TOMADO and MERGE studies for OA and CPAP. Costs, considered from a United States payer perspective, were projected over lifetime for a 48-year-old cohort, 68% of whom were male. An incremental cost-effectiveness ratio (ICER) threshold of USD150,000 per QALY gained was applied.

RESULTS

From a baseline AHI of 10.2 events/hour, NMES, OA and CPAP reduced the AHI to 6.9, 7.0 and 1.4 events/hour respectively. Long-term therapy adherence was estimated at 65-75% for NMES and 55% for both OA and CPAP. Compared to no treatment, NMES added between 0.268 and 0.536 QALYs and between USD7,481 and USD17,445 in cost, resulting in ICERs between USD15,436 and USD57,844 per QALY gained. Depending on long-term adherence assumptions, either NMES or CPAP were found to be the preferred treatment option, with NMES becoming more attractive with younger age and assuming CPAP was not used for the full night in all patients.

CONCLUSIONS

NMES might be a cost-effective treatment option for patients with mild OSA.

Association of obstructive sleep apnoea with long-term cardiovascular events in patients with acute coronary syndrome with or without hypertension: insight from the OSA-ACS project

BACKGROUND

A close relationship exists between obstructive sleep apnoea (OSA) and hypertension. However, the impact of hypertension on the prognostic significance of OSA in patients with acute coronary syndrome (ACS) remains unclear.

METHODS

This is a post hoc analysis of the OSA-ACS project, which consecutively included patients with ACS and receiving overnight sleep study from June 2015 to January 2020. OSA was defined as AHI ≥15 events/hour. The primary outcome was major adverse cardiovascular and cerebrovascular events (MACCE), including a composite of cardiovascular death, myocardial infarction, stroke, ischemia-driven revascularisation or hospitalisation for unstable angina or heart failure.

RESULTS

A total of 1927 patients with ACS were finally enrolled in this study. The mean patient age was 56.4±10.5 years. Among them, 1247 (64.7%) patients had hypertension, and 1014 (52.6%) patients had OSA. During 2.9 (1.5, 3.6) years of follow-up, OSA was associated with an increased risk of MACCE among patients with hypertension (HR=1.35, 95% CI 1.04 to 1.75, p=0.02), but not in patients without hypertension (HR=1.15, 95% CI 0.79 to 1.68, p=0.47). The interaction between OSA and hypertension for MACCE was not statistically significant (interaction p=0.29). For patients with pre-existing hypertension, OSA was associated with an increased risk of MACCE only among those with grade 3 hypertension (HR 1.54, 95% CI 1.12 to 2.13, p=0.008), but not those with grade 1 or 2 hypertension.

CONCLUSIONS

OSA was associated with an increased risk of MACCE following ACS in patients with hypertension, especially in patients with pre-existing severe hypertension. These findings highlight the importance of identifying OSA in ACS patients with hypertension.

TRIAL REGISTRATION NUMBER

NCT03362385.

Society of Anesthesia and Sleep Medicine Position Paper on Patient Sleep During Hospitalization

This article addresses the issue of patient sleep during hospitalization, which the Society of Anesthesia and Sleep Medicine believes merits wider consideration by health authorities than it has received to date. Adequate sleep is fundamental to health and well-being, and insufficiencies in its duration, quality, or timing have adverse effects that are acutely evident. These include cardiovascular dysfunction, impaired ventilatory function, cognitive impairment, increased pain perception, psychomotor disturbance (including increased fall risk), psychological disturbance (including anxiety and depression), metabolic dysfunction (including increased insulin resistance and catabolic propensity), and immune dysfunction and proinflammatory effects (increasing infection risk and pain generation). All these changes negatively impact health status and are counterproductive to recovery from illness and operation. Hospitalization challenges sleep in a variety of ways. These challenges include environmental factors such as noise, bright light, and overnight awakenings for observations, interventions, and transfers; physiological factors such as pain, dyspnea, bowel or urinary dysfunction, or discomfort from therapeutic devices; psychological factors such as stress and anxiety; care-related factors including medications or medication withdrawal; and preexisting sleep disorders that may not be recognized or adequately managed. Many of these challenges appear readily addressable. The key to doing so is to give sleep greater priority, with attention directed at ensuring that patients' sleep needs are recognized and met, both within the hospital and beyond. Requirements include staff education, creation of protocols to enhance the prospect of sleep needs being addressed, and improvement in hospital design to mitigate environmental disturbances. Hospitals and health care providers have a duty to provide, to the greatest extent possible, appropriate preconditions for healing. Accumulating evidence suggests that these preconditions include adequate patient sleep duration and quality. The Society of Anesthesia and Sleep Medicine calls for systematic changes in the approach of hospital leadership and staff to this issue. Measures required include incorporation of optimization of patient sleep into the objectives of perioperative and general patient care guidelines. These steps should be complemented by further research into the impact of hospitalization on sleep, the effects of poor sleep on health outcomes after hospitalization, and assessment of interventions to improve it.

Prevalence of sleep-related breathing disorders and associated risk factors among people with dementia: A meta-analysis

OBJECTIVE

Sleep-related breathing disorders (SRBD) have shown to cause worsened cognitive impairment among people with dementia. Therefore, we conducted the first meta-analysis to estimate the prevalence of SRBD among people with dementia.

METHODS

Comprehensive searches were conducted in Embase, Ovid-MEDLINE, PubMed, PsycINFO, Scopus, Web of Science, and CINAHL. The generalized linear mixed model (GLMM) was used for the pooled prevalence analysis and heterogeneity using I² test and Cochran's Q-statistic in R-software. Study quality was assessed by Hoy's risk of bias assessment tool. Overall, 20 studies from 1282 studies were included with 1461 participants.

RESULTS

The pooled prevalence of SRBD among dementia was 59% (95%CI: 44%-73%) with 55% (95%CI: 34%-74%) for obstructive sleep apnea (OSA), 49% (95%CI: 25%-73%) for unspecified SRBD, and 11% (95%CI: 5%-21%) for central sleep apnea (CSA). Regarding dementia subtypes, the prevalence of SRBD was 89% (95%CI: 61%-97%) for Alzheimer's dementia, 56% (95%CI: 48%-63%) for Parkinson's and Idiopathic Parkinson's dementia, and 16% (95%CI: 8%-30%) for Huntington's dementia. Significant moderator variables were male, body mass index, larger waist and hip circumference, waist-hip ratio, and comorbidities including hypertension, dyslipidemia, renal disease, diabetes, heart disease, and stroke.

CONCLUSIONS

There is considerable high prevalence of SRBD among dementia people, with OSA and unspecified SRBD being fivefold higher than CSA. Regarding dementia subtypes, Parkinson's and Idiopathic Parkinson's, and Alzheimer's dementia had four to sixfold increased risk of presenting with SRBD than Huntington's dementia. Therefore, assessment and management of SRBD in Alzheimer's, and Parkinson's and Idiopathic Parkinson's dementia deserves more attention in future research.

Clinical Characteristics and Surgical Outcomes of Obstructive Sleep Apnea Patients With Mixed Apnea Components

OBJECTIVE

This study was aimed to investigate clinical implications of mixed apnea (MA) in patients with obstructive sleep apnea (OSA), particularly whether surgical outcomes differ between OSA patients with and without MA events.

STUDY DESIGN

Retrospective cohort study.

SETTING

Single tertiary medical center.

METHODS

Eighty-eight patients with OSA who underwent multilevel upper airway surgery were included. Patients were divided into 2 groups according to the presence of MA events: "pure group" (n = 30) and "mixed group" (n = 58). The clinical characteristics and surgical outcomes were compared between the 2 groups.

RESULTS

The mixed group included more males (P = .020) and hypertensive patients (P = .009) and had a higher apnea-hypopnea index (AHI; P < .001) than the pure group. The surgical success rate was lower in the mixed group (29.3%) than in the pure group (73.3%; P < .001). Furthermore, the postoperative improvements in total AHI (P < .001), supine AHI (P < .001), and oxygen desaturation index (P = .006) were lower in the mixed group than in the pure group. Logistic regression analysis confirmed that the presence of MA (P = .002) was an independent predictor of poor surgical outcomes in patients with OSA.

CONCLUSION

OSA patients with MA showed different clinical features and poor surgical outcomes compared to those without MA. These results imply that OSA with MA components may have a distinct pathophysiology, and the presence of MA should be considered in the surgical treatment of OSA.

Hour-to-hour variability of respiratory sleep indices and ambulatory blood pressure

STUDY OBJECTIVES

Respiratory sleep indices are traditionally reported on the basis of the average total sleep time. The relationship between the hour-to-hour variability of these parameters and blood pressure (BP) has not been reported.

METHODS

We evaluated the associations of the hour-to-hour variability of the apnea-hypopnea index (AHI), oxygen desaturation index (ODI), and lowest oxygen saturation with the 24-h ambulatory BP in patients with hypertension and newly diagnosed obstructive sleep apnea. A total of 147 patients underwent polysomnography, based on which obstructive sleep apnea was diagnosed in 106 patients; these patients underwent 24-h ambulatory BP monitoring within the next 30 days. Each polysomnogram was divided into hourly reports to calculate the variability of the respiratory sleep indices. Variability independent of the mean was considered the primary measure of variability.

RESULTS

The median number of hourly polysomnogram reports was 7 (range, 4-8). The hour-to-hour variability of both AHI and ODI, but not of the lowest oxygen saturation, was correlated with the 24-h pulse pressure, 24-h systolic BP, and awake systolic BP (p < 0.05 for all). The fully adjusted linear regression analysis indicated that the hour-to-hour variability of AHI and ODI remained associated with the 24-h pulse pressure (AHI: β coefficient, 0.264 [95% CI = 0.033-0.495], p = 0.026; ODI: β coefficient, 0.450 [95% CI = 0.174-0.726], p = 0.002).

CONCLUSIONS

The hour-to-hour variability of AHI and ODI is independently associated with the 24-h pulse pressure. Further investigations are warranted to evaluate the clinical relevance of this new-found association.

Sex-specific differences in diagnostic approaches of inpatient sleep testing for obstructive sleep apnea

BACKGROUND

Few studies have investigated sex-specific disparities in inpatient sleep testing. We postulate that women are more likely to have a milder degree of obstructive sleep apnea (OSA) and lower extent of hypoxia on Type III sleep studies versus polysomnography (PSG).

PATIENTS AND METHODS

The Cleveland Clinic Sleep laboratory registry was leveraged to identify all adult inpatient sleep studies performed for OSA. Demographics, comorbidities, and sleep study measures were collected and compared by sex and sleep study type. Logistic regression was used to examine sleep study type predictive of OSA (apnea hypopnea index [AHI; ≥5, ≥15 and ≥ 30]) and hypoxia, (median percentage of sleep time spent at <90% SaO2 [TST<90%,≥ 11%,] adjusted for covariates.

RESULTS

The sample 778 patients had a mean age of 56.1 ± 16.1 years; 44.5% were female and 72.2% Caucasian. At an AHI≥5, women showed an increase odds of OSA (adjusted, OR = 2.04,95%; CI:1.24-3.35, p = 0.005) with Type III sleep study vs PSG compared to men. At an AHI≥15, men had less odds of OSA (adjusted OR = 0.60,95%CI:0.39-0.90,p = 0.015) with Type III sleep study vs PSG compared to women (OR = 1.15,95%CI:0.72-1.85,p = 0.56), with an interaction p-value of 0.040. These results were attenuated when the analysis was restricted using the 3% hypopnea scoring rule. Men and women had higher odds of TST <90 ≥ 11% (OR:2.60,95%CI:1.60-4.21,p=<0.001; OR:3.46,95%CI:1.97-6.05,p < 0.001) with Type III sleep study versus PSG, albeit no sex-interaction was observed.

CONCLUSIONS

These results suggest that sex-specific differences in diagnostic performance of sleep testing type in the inpatient setting should be considered according to level of OSA severity, which are influenced by hypopnea-related desaturation extent.

How Would You Manage This Patient With Chronic Insomnia? : Grand Rounds Discussion From Beth Israel Deaconess Medical Center

Insomnia, which is characterized by persistent sleep difficulties in association with daytime dysfunction, is a common concern in clinical practice. Chronic insomnia disorder is defined as symptoms that occur at least 3 times per week and persist for at least 3 months. The American Academy of Sleep Medicine (AASM) published recent guidelines on behavioral and psychological treatment as well as pharmacologic therapy for chronic insomnia disorder. Regarding behavioral and psychological approaches, the only intervention strongly recommended was multicomponent cognitive behavioral therapy for insomnia. Regarding pharmacologic treatment, the AASM, based on weak evidence, suggested a limited number of medications that might be useful and others that probably are not. Here, 2 clinicians with expertise in sleep disorders-one a clinical psychologist and the other a physician-debate the management of a patient with chronic insomnia who has been treated with medications. They discuss the role of behavioral and psychological interventions and pharmacologic therapy for chronic insomnia and how the primary care practitioner should approach such a patient.

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

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

Vagal milieu or electrophysiologic substrate? The link between atrial fibrillation and obstructive sleep apnea

Atrial fibrillation is the most common cardiac arrhythmia with its prevalence expected to increase to 12.1 million people in the United States by 2030. Chronic underlying conditions that affect the heart and lungs predispose patients to develop atrial fibrillation. Obstructive sleep apnea is strongly associated with atrial fibrillation. Several pathophysiological mechanisms have been proposed to elucidate this relationship which includes electrophysiological substrate modification and the contribution of the autonomic nervous system. In this comprehensive review, we highlight important relationships and plausible causality between obstructive sleep apnea and atrial fibrillation which will improve our understanding in the evaluation, management, and prevention of atrial fibrillation. This is the most updated comprehensive review of the relationship between obstructive sleep apnea and atrial fibrillation.

Application value of joint STOP-Bang questionnaire and Epworth Sleepiness Scale in screening for obstructive sleep apnea

Objective

This paper evaluates the application value of the STOP-Bang questionnaire combined with the Epworth Sleepiness Scale (ESS) in screening for obstructive sleep apnea (OSA) in the population.

Method

Thousand-six hundred seventy-one patients with suspected OSA who visited the Sleep Medicine Center of the First Affiliated Hospital of Guangzhou Medical University from August 2017 to August 2020 were monitored by overnight polysomnography (PSG) after completing the ESS scale and STOP-Bang questionnaire. The sensitivity, specificity, positive predictive value, negative predictive value and receiver operating characteristic (ROC) curves of the two scales were calculated, and the accuracy in predicting OSA of the STOP-Bang questionnaire combined with ESS was analyzed.

Results

With Apnea Hypopnea Index (AHI) cutoffs of ≥5, ≥15 and ≥30 events/h, the areas under the ROC curve scored by STOP-Bang were 0.724, 0.703 and 0.712, and those of ESS were 0.632, 0.634 and 0.695; the diagnostic odds ratio (DOR) values of STOP-Bang for OSA, moderate to severe OSA, and severe OSA were 3.349, 2.651 and 3.189, and those of ESS were 2.665, 2.279 and 3.289. The STOP-Bang score of three was used as the cut-off point for OSA diagnosis with higher sensitivity and lower specificity, while ESS had higher specificity. STOP-Bang (≥3) combined with ESS significantly improved its specificity for predicting OSA.

Conclusion

The STOP-Bang questionnaire is a simple and effective new tool for screening patients for OSA, while a STOP-Bang score of ≥3 combined with ESS can further improve its specificity. Thus, we suggest further screening with ESS after a STOP-Bang score of ≥3 in suspected patients.

Assessment of hypertension in obstructive sleep apnea by ambulatory blood pressure monitoring: a systematic review and meta-analysis

Among obstructive sleep apnea (OSA) patients, there exists a high prevalence of hypertension. Determining the optimal blood pressure (BP) monitoring modality in this population will lead to a better understanding of hypertension profiles and a more accurate diagnosis of hypertension. PubMed, Ovid/Medline, Web of Science, Scopus, Cochrane Library, and CINAHL databases were screened, and the relevant articles regarding BP monitoring in OSA patient population were selected. Studies evaluating both ambulatory (ABPM) and office BP measurements were selected to be analyzed for the hypertension diagnosis specificity of ABPM measurement in OSA patients compared with office measurements. If reported, additional information regarding white-coat, masked hypertension, and circadian BP pattern prevalence was included. A cumulative analysis of five studies revealed a prevalence of hypertension based on BP to be 44%, whereas a cumulative analysis of four studies revealed a prevalence of hypertension based on ABPM to be 66%. Excluding a study with the nighttime assessment of hypertension reduced the cumulative prevalence of hypertension in OSA patients to 59%. The cumulative prevalence of Studies demonstrated the prevalence of masked and white-coat hypertension to be 34 and 9%, respectively. As a higher prevalence of hypertension was detected by ABPM and nighttime measurement, it can be deduced that ABPM is more sensitive in determining OSA patients with hypertension, and that nighttime ABPM further increases this sensitivity. The presence of masked and white-coat hypertension in OSA patients underlines the importance of correct hypertension diagnosis as it affects further management in this population with increased cardiovascular risk.

Association of traffic air pollution with severity of obstructive sleep apnea in urban areas of Northern Taiwan: A cross-sectional study

BACKGROUND

Although recent studies have indicated an association between obstructive sleep apnea (OSA) and air pollution, they have reported inconsistent results. Moreover, few studies investigated the effects of short-term air pollution exposure.

OBJECTIVE

To estimate the health effects of short- and long-term exposure to traffic air pollution on mild OSA in Taipei.

METHODS

We collected participants' data from Taipei Sleep Center and air pollution data from Taiwan Environmental Protection Administration. A spatiotemporal model was used to estimate the individual exposure level. Generalized linear models were used to assess the percent change of overall apnea-hypopnea index (AHI), AHI in rapid eye movement period (AHI-REM), AHI in non-REM (AHI-NREM), and oxygen desaturation index (ODI) associated with an interquartile (IQR) increase in personal pollution exposure. A generalized logistic model was used to estimate the ORs of different severities of OSA compared with the reference group.

RESULTS

In the patients with AHI of <15, both short- and long-term exposure to NO₂ were significantly associated with AHI and ODI increases: an IQR increase in 2-year mean NO₂ increased 7.3% of AHI and 8.4% of ODI; these values were the highest among all exposure windows. The effects of NO₂ on AHI increase were stronger in the men and younger patients. Moreover, the association between AHI and NO₂ in the patients with AHI of <15 was mediated by the REM stage. NO₂ exposure was associated with an increased risk of mild OSA that reached up to 24.8% per IQR increase in NO₂ averaged over 2 years. PM_2.5 exerted no effects on AHI, but an IQR increase in 1-year and 2-year mean PM_2.5 was associated with 6.8% and 8.8% increases in ODI, respectively.

CONCLUSIONS

Both short- and long-term exposure to traffic air pollution were associated with the risk of mild OSA, which was modified by REM stage.

Age and sex differences on the association between anxiety disorders and obstructive sleep apnea: A nationwide case-control study in Taiwan

AIM

The aim of this study was to examine the association between anxiety disorders and obstructive sleep apnea (OSA).

METHODS

This is a population-based, retrospective case-control study using Taiwan's nationwide database. We included patients with OSA aged ≥12 years, diagnosed according to the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes: 327 and 780. Each enrolled patient with OSA needed to undergo a polysomnography examination within 1 year pre- or post-OSA occurrence. Patients with OSA and controls were selected in a 1:4 ratio. Patients with anxiety disorders (ICD-9-CM code 300) were diagnosed by board-certified psychiatrists and required to visit the outpatient clinic at least three times per year. Multivariate logistic regression and interaction analyses were used to evaluate the objective association.

RESULTS

This study enrolled 7987 and 31 948 participants with and without OSA, respectively. A significant difference in anxiety exposure was observed only pre-OSA diagnosis but not post-OSA diagnosis. Compared with patients without anxiety disorders: (i) those with anxiety disorders had an adjusted odds ratio (aOR) of ≈1.864 in OSA comorbidity (aOR = 1.864; 95% confidence interval [CI] = 1.337-2.405); and (ii) subgroup analysis showed a significant interaction that anxiety patients of male sex, aged 18 to 44 years, aged 45 to 64 years, and hypertension had a higher aOR in OSA comorbidity (aOR = 2.104 [95% CI = 1.436-2.589], aOR = 1.942 [95% CI = 1.390-2.503], aOR = 2.179 [95% CI = 1.564-2.811], and aOR = 2.092 [95% CI = 1.497-2.706], respectively).

CONCLUSION

The study revealed a higher ratio of previous anxiety exposure in patients with OSA. Compared with those without anxiety, anxiety patients of male sex, aged 18 to 64 years, and with hypertension had a higher risk of OSA comorbidity.

Can Weight Loss Improve the Cardiovascular Outcomes of Patients with Obesity and Obstructive Sleep Apnea?

Cardiovascular events are the primary cause of mortality in patients with obstructive sleep apnea and obesity. The rising prevalence of obstructive sleep apnea in recent decades has been linked to increasing rates of obesity. Obstructive sleep apnea has also been linked with many different cardiovascular diseases including coronary artery disease, stroke, heart failure, hypertension, and atrial fibrillation. Obesity is an increasing health concern globally, in part because obesity complications such as hypertension, diabetes, and obstructive sleep apnea increase the risk of cardiovascular diseases. More than 10% weight loss may be required to prevent or reverse obesity complications. Treatment approaches to obesity include nutritional therapy, exercise therapy, pharmacotherapy, and surgical therapies. This review intends to identify the effects of weight loss on cardiovascular outcomes in patients with obesity and obstructive sleep apnea. Despite the strong association between cardiovascular diseases and obstructive sleep apnea, randomized trials have failed to demonstrate that treatment of obstructive sleep apnea reduces cardiovascular events, even in patients with established cardiovascular diseases. Weight loss in patients with obstructive sleep apnea improves HbA1c, systolic blood pressure, HDL cholesterol, and triglycerides, but thus far no changes in cardiovascular events have been shown. The combination of weight loss with continuous positive airway pressure (CPAP) appears more beneficial than either treatment in isolation. Large well-controlled trials in patients with obstructive sleep apnea to assess the effects of different weight reduction programs on cardiovascular disease are still needed.

Sulforaphane Attenuates Chronic Intermittent Hypoxia-Induced Brain Damage in Mice via Augmenting Nrf2 Nuclear Translocation and Autophagy

Obstructive sleep apnea–hypopnea syndrome (OSAHS), typically characterized by chronic intermittent hypoxia (CIH), is associated with neurocognitive dysfunction in children. Sulforaphane (SFN), an activator of nuclear factor E2-related factor 2 (Nrf2), has been demonstrated to protect against oxidative stress in various diseases. However, the effect of SFN on OSAHS remains elusive. In this research, we investigated the neuroprotective role of SFN in CIH-induced cognitive dysfunction and underlying mechanisms of regulation of Nrf2 signaling pathway and autophagy. CIH exposures for 4 weeks in mice, modeling OSAHS, contributed to neurocognitive dysfunction, manifested as increased working memory errors (WMEs), reference memory errors (RMEs) and total memory errors (TEs) in the 8-arm radial maze test. The mice were intraperitoneally injected with SFN (0.5 mg/kg) 30 min before CIH exposure everyday. SFN treatment ameliorated neurocognitive dysfunction in CIH mice, which demonstrates less RME, WME, and TE. Also, SFN effectively alleviated apoptosis of hippocampal neurons following CIH by decreased TUNEL-positive cells, downregulated cleaved PARP, cleaved caspase 3, and upregulated Bcl-2. SFN protects hippocampal tissue from CIH-induced oxidative stress as evidenced by elevated superoxide dismutase (SOD) activities and reduced malondialdehyde (MDA). In addition, we found that SFN enhanced Nrf2 nuclear translocation to hold an antioxidative function on CIH-induced neuronal apoptosis in hippocampus. Meanwhile, SFN promoted autophagy activation, as shown by increased Beclin1, ATG5, and LC3II/LC3I. Overall, our findings indicated that SFN reduced the apoptosis of hippocampal neurons through antioxidant effect of Nrf2 and autophagy in CIH-induced brain damage, which highlights the potential of SFN as a novel therapy for OSAHS-related neurocognitive dysfunction.

Progression of Type B Intramural Hematoma Patients with Obstructive Sleep Apnea

OBJECTIVE

This study aimed to estimate the influence of obstructive sleep apnea (OSA) on type B intramural hematoma (IMHB) progression.

METHODS

All 127 patients received sleep evaluations and esophageal pressure measurements. Variables associated with aorta-related adverse events and mortality were summarized by logistic regression analysis and Cox proportional hazard models. Competing risk analysis of death was used to estimate aorta-related and non-aorta-related mortality.

RESULTS

The OSA group had a higher aorta-related adverse events rate (46% vs. 4%, P<0.001). The mean nighttime systolic pressure (OR, 1.24; 95% CI, 1.11-1.38, P<0.001) was associated with aorta-related adverse events during the acute phase. Thoracic endovascular aortic repair (TEVAR) (HR, 16.2; 95% CI, 7.68-34.22, P<0.001) and mean morning systolic pressure (HR, 1.43; 95% CI, 1.22-1.68, P<0.001) were associated with a higher rate of occurrence of aorta-related adverse events. The occurrence of OSA (HR, 3.19; 95% CI, 2.57-12.15, P<0.001) and mean morning systolic pressure (HR, 1.59; 95% CI, 1.27-2.01, P=0.002) were significantly associated with aorta-related mortality. Competing risk analysis revealed significantly higher aorta-related mortality in the OSA group (11.8% vs. 2.0%, P=0.0412). A neutrophil-to-lymphocyte ratio (NLR) of > 3.52 (specificity: 90.2%, sensitivity: 89.5%) and a mean platelet volume-to-platelet ratio (MPV/PLT) of > 0.049 (specificity: 98.0%, sensitivity: 98.7%) have diagnostic value for detecting OSA in IMHB.

CONCLUSIONS

OSA leads to a higher aorta-related adverse event rate and mortality in patients with IMHB. Variables associated with outcomes include TEVAR, mean morning/nighttime systolic pressure and OSA. The NLR and MPV/PLT ratios are valuable for detecting OSA in IMHB patients.

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

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

[A long-term ischemic stroke risk score model in patients aged 60 years and older with obstructive sleep apnea: a multicenter prospective cohort study]

OBJECTIVE

To analyze the independent risk factors of long-term ischemic stroke and establish a nomogram for predicting the long-term risks in elderly patients with obstructive sleep apnea (OSA).

METHODS

This multicenter prospective cohort study was conducted from January, 2015 to October, 2017 among consecutive elderly patients (≥60 years) with newly diagnosed OSA without a history of cardio-cerebrovascular diseases and loss of important clinical indicators. The follow-up outcome was the occurrence of ischemic stroke. The baseline demographic and clinical data, sleep parameters, laboratory and ultrasound results were collected from all the patients, who were randomized into the modeling group (n=856) and validation group (n=258) at a 3∶1 ratio. LASSO regression was used for variable reduction and dimension screening, and the risk score prediction model of ischemic stroke was established based on Cox proportional hazard regression.

RESULTS

In the total of 1141 patients enrolled in this study, 58 (5.08%) patients experienced ischemic stroke during the median follow-up of 42 months (range 41-54 months). The cumulative incidence of ischemic stroke was 5.14% in the model group and 4.91% in the verification group (P < 0.05). Age (HR=3.44, 95% CI: 2.38- 7.77), fasting blood glucose (FPG) (HR=2.13, 95% CI: 1.22-3.72), internal diameter of the ascending aorta (HR=2.60, 95% CI: 1.0- 4.47), left atrial anteroposterior diameter (HR=1.98, 95% CI: 1.75-2.25) and minimum oxygen saturation (LSpO₂) (HR=1.57, 95% CI: 1.20-1.93) were identified as independent risk factors for ischemic stroke (P < 0.05 or 0.01). A long-term ischemic stroke risk score model was constructed based the regression coefficient ratios of these 5 risk variables. Before and after the application of the Bootstrap method, the AUC of the cohort risk score model was 0.84 (95% CI: 0.78- 0.90) and 0.85 (95% CI: 0.78- 0.89) in the model group and was 0.83 (95% CI: 0.73-0.93) and 0.82 (95%CI: 0.72-0.90) in the verification group, respectively, suggesting a good prediction efficiency and high robustness of the model. At the best clinical cutoff point, the cumulative incidence of ischemic stroke was significantly higher in the high-risk group than in the low-risk group (P=0.021).

CONCLUSION

This model can help to identify high-risk OSA patients for early interventions of the risks of ischemic stroke associated with OSA.

Effect of acetazolamide on obstructive sleep apnoea in highlanders: protocol for a randomised, placebo-controlled, double-blinded crossover trial

INTRODUCTION

Obstructive sleep apnoea (OSA) is a highly prevalent disease that causing systemic hypertension. Furthermore, altitude-dependent hypobaric hypoxic condition and Tibetan ethnicity have been associated with systemic hypertension independent of OSA, therefore patients with OSA living at high altitude might be at profound risk to develop systemic hypertension. Acetazolamide has been shown to decrease blood pressure, improve arterial oxygenation and prevent high altitude periodic breathing in healthy volunteers ascending to high altitude and decrease blood pressure in patients with systemic hypertension at low altitude. However, the effect of acetazolamide on 24-hour blood pressure, sleep-disordered disturbance and daytime cognitive performance in patients with OSA permanently living at high altitude has not been studied.

METHODS AND ANALYSIS

This study protocol describes a randomised, placebo-controlled, double-blinded crossover trial. Highland residents of both sexes, aged 30-60 years, Tibetan ethnicity, living at an elevation of 3650 m and apnoea-hypopnoea index over 15/hour will be included. Participants will be randomly assigned to a 2×2 week treatment period starting with 750 mg/day acetazolamide followed by placebo treatment or vice versa, separated by a 1-week wash-out phase. Clinical assessments, 24-hour ambulatory blood pressure monitoring (ABPM), polysomnography (PSG), near-infrared spectroscopy, nocturnal fluid shift and cognitive performance will be assessed before and at the end of each treatment period. The primary outcome will be the difference in 24-hour mean blood pressure between acetazolamide therapy and placebo; secondary outcomes will be the difference in other 24-hour ABPM-derived parameters, PSG-derived parameters, cognitive performance and overnight change in different segments of fluid volume between acetazolamide therapy and placebo. Accounting for potential dropouts, 40 participants will be recruited.

ETHICS AND DISSEMINATION

The protocol was approved by the West China Hospital of Sichuan University Biomedical Research Ethics Committee. Recruitment will start in spring 2022. Dissemination of the results include presentations at conferences and publications in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ChiCTR2100049304.

The association of age with continuous positive airway pressure ventilation acceptance in an outpatient cohort of patients with obstructive sleep apnea

STUDY OBJECTIVES

This study examined the association between age and continuous positive airway pressure (CPAP) acceptance in a consecutive series of patients with obstructive sleep apnea being managed in a physician-led outpatient CPAP acclimatization program in Canberra, Australia.

METHODS

We performed a retrospective consecutive case series analysis of registry data collected from patients attending the Canberra Hospital PAP Acclimatization Clinic between 2011 and 2019. Data on patient demographics, diagnostic polysomnography results, CPAP device download parameters during acclimatization, and overall CPAP acceptance at the end of acclimatization were extracted from the Clinic Registry. Analysis of variance and chi-square were used to assess for associations between patient age, CPAP acceptance, and other clinical characteristics. Univariate and stepwise multiple logistic regression was used to identify predictors of CPAP acceptance.

RESULTS

We found that 1,075 consecutive CPAP trials among 1,043 patients were eligible for inclusion. CPAP acceptance was lower in those aged > 75 years compared with those aged ≤ 75 years (odds ratio: 0.57; 95% confidence interval, 0.36-0.92; P = .02). Patients aged > 75 years had lower body mass index, had higher initial and final visit 95th percentile mask leak, and were less likely to be CPAP naïve. Using univariate regression, younger age, severe obstructive sleep apnea, obesity, shorter trial duration, more clinic visits, higher initial visit CPAP usage, and lower final visit mask leak were predictors of CPAP acceptance. In a multiple logistic regression model, younger age, severe obstructive sleep apnea, shorter trial duration, more clinic visits, higher first visit usage, and lower final visit leak predicted acceptance.

CONCLUSIONS

Older age is associated with lower CPAP acceptance. The factors contributing to this association are unclear and require further investigation.

CITATION

Han M, Wee R, Shadbolt B, Huang H-CC. The association of age with continuous positive airway pressure ventilation acceptance in an outpatient cohort of patients with obstructive sleep apnea. J Clin Sleep Med. 2022;18(1):217-224.

The 3% Oxygen Desaturation Index is an Independent Risk Factor for Hypertension Among Children with Obstructive Sleep Apnea

BACKGROUND

Obstructive sleep apnea (OSA) and obesity are both directional risk factors of hypertension. Chronic intermittent hypoxemia (IH) is a commonly observed pathophysiological mechanism involved in multiple comorbidities of OSA. However, their interactions are not well understood in children. This study aimed to investigate the associations of IH indexes (oxygen desaturation index 3% [ODI3], mean peripheral oxygen saturation [SpO₂], least SpO₂, and time with SpO₂ < 85%), apnea-hypopnea index, and weight status with hypertension in a sample of pediatric OSA patients.

METHODS

The medical records of 365 pediatric OSA patients were retrospectively reviewed in this cross-sectional study. Demographics, anthropometrics, standard in-laboratory polysomnography, and nocturnal blood pressure were collected. Multivariate logistic regression with forward selection was used to identify independent predictors of hypertension.

RESULTS

Multivariate logistic regression analysis showed that ODI3 (odds ratio [OR] = 1.02, 95% confidence interval [CI] = 1.01-1.03) and body mass index z-score (OR = 1.34, 95% CI = 1.12-1.60) were independent continuous predictors of pediatric hypertension, whilst severe OSA (OR = 2.62, 95% CI = 1.60-4.29) and overweight/obesity (OR = 2.63, 95% CI = 1.59-4.34) were independent categorical predictors. Traditional risk factors including male sex (OR = 2.33, 95% CI = 1.02-5.33), late childhood/adolescence (OR = 1.98, 95% CI = 1.01-3.88), and overweight/obesity (OR = 2.97, 95% CI = 1.56-5.67) combined with sleep hypoxemia (least SpO₂ ≤ 95%) (OR = 2.24, 95% CI = 1.16-4.04) predicted hypertension (R ² = 0.21) in the severe IH subgroup (n = 205), while the no/mild IH subgroup (n = 160) had an entirely different predictor, severe OSA (OR = 3.81, 95% CI = 1.49-9.74) (R ² = 0.07).

CONCLUSION

The close relationships among IH, overweight/obesity, and hypertension highlight the importance of reducing IH and body weight in children with OSA.

Development and Comparison of Predictive Models Based on Different Types of Influencing Factors to Select the Best One for the Prediction of OSAHS Prevalence

OBJECTIVE

This study aims to retrospectively analyze numerous related clinical data to identify three types of potential influencing factors of obstructive sleep apnea-hypopnea syndrome (OSAHS) for establishing three predictive nomograms, respectively. The best performing one was screened to guide further clinical decision-making.

METHODS

Correlation, difference and univariate logistic regression analysis were used to identify the influencing factors of OSAHS. Then these factors are divided into three different types according to the characteristics of the data. Lasso regression was used to filter out three types of factors to construct three nomograms, respectively. Compare the performance of the three nomograms evaluated by C-index, ROC curve and Decision Curve Analysis to select the best one. Two queues were obtained by randomly splitting the whole queue, and similar methods are used to verify the performance of the best nomogram.

RESULTS

In total, 8 influencing factors of OSAHS have been identified and divided into three types. Lasso regression finally determined 6, 3 and 4 factors to construct mixed factors nomogram (MFN), baseline factors nomogram (BAFN) and blood factors nomogram (BLFN), respectively. MFN performed best among the three and also performed well in multiple queues.

CONCLUSION

Compared with BAFN and BLFN constructed by single-type factors, MFN constructed by six mixed-type factors shows better performance in predicting the risk of OSAHS.

MiR-142-3p as an Indicator of OSA Severity Predicts Prognosis in Lung Adenocarcinoma with OSA

PURPOSE

The aim was to explore the correlation between Obstructive sleep apnea (OSA) and Lung adenocarcinoma malignant prognosis and evaluate the miR-142-3p was used as an OSA severity indicator to predict the prognosis of Lung adenocarcinoma patients.

METHODS

This study comprised of 21 diagnosed lung adenocarcinoma patients with or without OSA. The sleep-related variables and tumor pathology were recorded. Hypoxia-inducible factor-1α (HIF1α) and ki67 expression were analyzed by immunohistochemistry in tumor samples. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to assess the level of miR-142-3p.

RESULTS

Lung adenocarcinoma with OSA showed higher apnea-hypopnea index (AHI), oxygen desaturation index (ODI), and the lower lowest pulse oxygen saturation (LS_PO₂) compared to Lung adenocarcinoma without OSA (P<0.05), and patients with severer OSA have an advanced TNM stage (P=0.004) and metastasis rate (p=0.032). In addition, OSA may down-regulate the miR-142-3p expression in patients with Lung adenocarcinoma, and the patients with low miR-142-3p expression exhibited severe OSA. MiR-142-3p levels significantly decreased in the advanced TNM stage (p=0.015), and the expression of miR-142-3p was negatively associated with AHI (r= -0.505, p=0.020), ODI (r= -0.513, p=0.017).

CONCLUSION

OSA severity may increase Lung adenocarcinoma malignant prognosis. OSA may down-regulate the expression of miR-42-3p. The expression of miR-142-3p was inversely correlated with AHI and ODI as a surrogate of OSA severity. Additionally, the low miR-142-3p expression level was significantly associated with advanced TNM stage in Lung adenocarcinoma patients.

Association Between Triglyceride Glucose Index-Waist Circumference and Risk of First Myocardial Infarction in Chinese Hypertensive Patients with Obstructive Sleep Apnoea: An Observational Cohort Study

PURPOSE

This study aimed to investigate the association between triglyceride glucose index-waist circumference (TyG-WC) and the risk of first myocardial infarction (MI) in Chinese hypertensive patients with obstructive sleep apnoea (OSA).

METHODS

This study was an observational cohort study. A total of 2224 Chinese hypertensive patients with OSA without a history of MI were included in this study. Hazard ratio (HR) and 95% confidence interval (CI) were estimated using multivariable Cox proportion hazard models. A generalized additive model was used to identify nonlinear relationships. Additionally, we performed hierarchical analysis and test for interaction.

RESULTS

During a median follow-up of 7.15 years, 85 incidents of MI developed. Overall, there was a positive association between TyG-WC and the risk of first MI. In the multivariable-adjusted model, the risk of MI increased with quartiles of the TyG-WC, the HR in quartile 4 versus quartile 1 was 4.29. A generalized additive model and a smooth curve fitting showed that there existed a similar J-shaped association between TyG-WC and the risk of first MI, with an inflection point at about 785.

CONCLUSION

Elevated levels of the baseline TyG-WC are associated with an increased risk of first MI. This finding indicates that the TyG-WC might be useful to identify the high risk of first MI in Chinese hypertensive patients with OSA.

Irisin Is Correlated with Blood Pressure in Obstructive Sleep Apnea Patients

BACKGROUND

Despite approximately 95% primary cases of hypertension, secondary hypertension seems to be common with resistant forms. Notably, obstructive sleep apnea (OSA) is known as a common cause of secondary hypertension and has a major characteristic of obesity. Irisin acts as a link between muscles and adipose tissues in obesity, playing an essential role in human blood pressure (BP) regulation. However, whether irisin is associated with secondary hypertension caused by OSA and how it takes effect essentially have not been elucidated.

PURPOSE

To investigate the changes of irisin and its relationship with BP in OSA.

METHODS

72 snoring patients finished Epworth Sleep Scale (ESS) evaluation before polysomnography (PSG). BP was the average of three brachial BP values by mercury sphygmomanometer. Serum irisin level was determined by enzyme-linked immunosorbent assay (ELISA). Results were analyzed by SPSS software.

RESULTS

Irisin was higher in the severe and quite severe group than that in control and nonsevere groups (p < 0.05). For BP, significant differences were found between the control group and the other three groups (p < 0.05) and between the quite severe and the other three groups (p ≤ 0.001). Positive correlations were found between irisin and apnea-hypopnea index (AHI), AHI and BP, and irisin level and BP. Negative correlations were between irisin and SpO2 nadir and SpO2 nadir and BP. Positive correlation still existed between AHI and irisin even after adjusting for some obesity-related variables.

CONCLUSIONS

Irisin may serve as a potential biomarker for severity of OSA independently of obesity and imply the development of hypertension.

Two effective clinical prediction models to screen for obstructive sleep apnoea based on body mass index and other parameters

BACKGROUND AND OBJECTIVE

The diagnosis of obstructive sleep apnea (OSA) relies on polysomnography which is time-consuming and expensive. We therefore aimed to develop two simple, non-invasive models to screen adults for OSA.

METHODS

The effectiveness of using body mass index (BMI) and a new visual prediction model to screen for OSA was evaluated using a development set (1769 participants) and confirmed using an independent validation set (642 participants).

RESULTS

Based on the development set, the best BMI cut-off value for diagnosing OSA was 26.45 kg/m², with an area under the curve (AUC) of 0.7213 (95% confidence interval (CI), 0.6861-0.7566), a sensitivity of 57% and a specificity of 78%. Through forward conditional logistic regression analysis using a stepwise selection model developed from observed data, seven clinical variables were evaluated as independent predictors of OSA: age, BMI, sex, Epworth Sleepiness Scale score, witnessed apnoeas, dry mouth and arrhythmias. With this new model, the AUC was 0.7991 (95% CI, 0.7668-0.8314) for diagnosing OSA (sensitivity, 75%; specificity, 71%). The results were confirmed using the validation set. A nomogram for predicting OSA was generated based on this new model using statistical software.

CONCLUSIONS

BMI can be used as an indicator to screen for OSA in the community. We created an internally validated, highly distinguishable, visual and parsimonious prediction model comprising BMI and other parameters that can be used to identify patients with OSA among outpatients. Use of this prediction model may help to improve clinical decision-making.

Top 100 influential manuscripts in obstructive sleep apnea: a bibliometric analysis

OBJECTIVE

This study aimed to explore the characteristics of the top 100 influential manuscripts on obstructive sleep apnea (OSA).

METHODS

All manuscripts in English were searched from the Thomson Reuters Web of Science database by using OSA-related terms and ranked based on citation frequency. The top 100 influential manuscripts were selected and further analyzed by author, subject, journal, year of publication, country of origin, and institution.

RESULTS

A total of 42,878 manuscripts were searched from the Web of Science. The top 100 influential manuscripts were published from 2005 to 2017, with a total citation frequency of 38,463 and a median citation frequency of 303 (range: from 210 to 2, 707). The American Journal of Respiratory and Critical Care Medicine published the largest number of manuscripts from the top 100 (n = 18; 5340 citations), followed by Sleep (n = 11; 3516 citations) and Chest (n = 7; 1784 citations). The most cited manuscript (Marin, J.M et al., Lancet 2005; 2707 citations) mainly analyzed long-term cardiovascular outcomes in men with OSA with/without continuous positive airway pressure. The most prevalent subject was associated diseases (n = 41), followed by treatments (n = 40). Most of the manuscripts were original articles (n = 63) based on observational clinical studies and published from American institutions (n = 60).

CONCLUSIONS

Our study identified the top 100 influential manuscripts on OSA and provides insights into the characteristics of the most highly cited manuscripts to improve our understanding and management of OSA.

An Update on Obstructive Sleep Apnea for Atherosclerosis: Mechanism, Diagnosis, and Treatment

The occurrence and development of atherosclerosis could be influenced by intermittent hypoxia. Obstructive sleep apnea (OSA), characterized by intermittent hypoxia, is world-wide prevalence with increasing morbidity and mortality rates. Researches remain focused on the study of its mechanism and improvement of diagnosis and treatment. However, the underlying mechanism is complex, and the best practice for OSA diagnosis and treatment considering atherosclerosis and related cardiovascular diseases is still debatable. In this review, we provided an update on research in OSA in the last 5 years with regard to atherosclerosis. The processes of inflammation, oxidative stress, autonomic nervous system activation, vascular dysfunction, platelet activation, metabolite dysfunction, small molecule RNA regulation, and the cardioprotective occurrence was discussed. Additionally, improved diagnosis such as, the utilized of portable device, and treatment especially with inconsistent results in continuous positive airway pressure and mandibular advancement devices were illustrated in detail. Therefore, further fundamental and clinical research should be carried out for a better understanding the deep interaction between OSA and atherosclerosis, as well as the suggestion of newer diagnostic and treatment options.

Which came first, obstructive sleep apnoea or hypertension? A retrospective study of electronic records over 10 years, with separation by sex

OBJECTIVES

Obstructive sleep apnoea (OSA) is a risk factor for hypertension (HTN), but the clinical progression of OSA to HTN is unclear. There are also sex differences in prevalence, screening and symptoms of OSA. Our objective was to estimate the time from OSA to HTN diagnoses in females and males.

DESIGN

Retrospective analysis of electronic health records (EHR) over 10 years (2006-2015 inclusive).

SETTING

University of California Los Angeles (UCLA) Health System in Los Angeles, California, USA.

PARTICIPANTS

4848 patients: females n=2086, mean (SD) age=52.8 (13.2) years; males n=2762, age=53.8 (13.5) years. These patients were selected from 1.6 million with diagnoses in the EHR who met these criteria: diagnoses of OSA and HTN; in long-term care defined by ambulatory visits at least 1 year prior and 1 year subsequent to the first OSA diagnosis; no diagnosis of OSA or HTN at intake; and a sleep study performed at UCLA.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome measure in each patient was time from the first diagnosis of OSA to the first diagnosis of HTN (OSA to HTN days). Since HTN and OSA are progressive disorders, a secondary measure was the relationship between OSA to HTN time and age (OSA to HTN=β₁×Age+β₀).

RESULTS

The median (lower and upper quartiles) days from OSA to HTN were: all -532 (-1439, -3); females -610 (-1579, -42); and males -451 (-1358, 0). Older age in both sexes was associated with less time to a subsequent HTN diagnosis or more time from a prior HTN diagnosis (β₁ days/year: all -16.9, females -18.3, males -15.9).

CONCLUSIONS

HTN was on average diagnosed years prior to OSA, with a longer separation in females. Our findings are consistent with underscreening of OSA, more so in females than males. Undiagnosed OSA may delay treatment for the sleep disorder and perhaps affect the development and progression of HTN.

Diagnostic and Therapeutic Approach to Sleep Disorders, High Blood Pressure and Cardiovascular Diseases: A Consensus Document by the Italian Society of Hypertension (SIIA)

Hypertension is a major contributor to fatal/nonfatal cardiovascular diseases, and timely identification and appropriate management of factors affecting hypertension and its control are mandatory public health issues. By inducing neurohormonal alterations and metabolic impairment, sleep disorders have an impact on a variety of cardiovascular risk factors, including hypertension, and ultimately increase the risk of cardiovascular events. There is evidence that qualitative and quantitative sleep disorders are associated with resistant hypertension and with impaired circadian blood pressure variations. However, sleep disturbances are often unrecognized, or heterogeneity exists in their management by non-specialists in the field. This document by the Italian Society of Hypertension summarizes the updated evidence linking sleep disorders to hypertension and cardiovascular diseases, the major underlying mechanisms, and the possible management strategies. A simplified, evidence-based diagnostic and therapeutic algorithm for comorbid hypertension and common sleep disorders, namely obstructive sleep apnoea and insomnia, is proposed.

Effect of Sleep Disturbances on Blood Pressure

This review summarizes recent literature addressing the association of short sleep duration, shift work, and obstructive sleep apnea with hypertension risk, blood pressure (BP) levels, and 24-hour ambulatory BP. Observational studies demonstrate that subjectively assessed short sleep increases hypertension risk, though conflicting results are observed in studies of objectively assessed short sleep. Intervention studies demonstrate that mild and severe sleep restriction are associated with higher BP. Rotating and night shift work are associated with hypertension as shift work may exacerbate the detrimental impact of short sleep on BP. Further, studies demonstrate that shift work may increase nighttime BP and reduce BP control in patients with hypertension. Finally, moderate to severe obstructive sleep apnea is associated with hypertension, particularly resistant hypertension. Obstructive sleep apnea is also associated with abnormal 24-hour ambulatory BP profiles, including higher daytime and nighttime BP, nondipping BP, and a higher morning surge. Continuous positive airway pressure treatment may lower BP and improve BP dipping. In conclusion, efforts should be made to educate patients and health care providers about the importance of identifying and treating sleep disturbances for hypertension prevention and management. Empirically supported sleep health interventions represent a critical next step to advance this research area and establish causality.