Efficacy of continuous positive airway pressure (CPAP) in patients with obstructive sleep apnea (OSA) and resistant hypertension (RH): Systematic review and meta-analysis

Nonpharmacologic Management of Hypertension in Older Adults

Hypertension is ubiquitous among older adults and leads to major adverse cardiovascular events. Nonpharmacologic lifestyle interventions represent important preventive and adjunct strategies in the treatment of hypertension and have benefits beyond cardiovascular disease in this population characterized by a high prevalence of frailty and comorbid conditions. In this review, the authors examine nonpharmacologic interventions with the strongest evidence to prevent cardiovascular disease with an emphasis on the older adults.

Resistant Hypertension in Older Adults

Resistant hypertension is a complex disorder that requires a comprehensive evaluation of several patient characteristics. Attention should be paid to medication and lifestyle adherence, and investigation into potential secondary causes of resistant hypertension should occur as clinically indicated. Moreover, a shared, multidisciplinary decision-making approach with the patient, specialized care providers, and family members may enhance blood pressure control.

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

AIMS

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

METHODS AND RESULTS

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

CONCLUSIONS

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

SLEEP APNEA IS A COMMON AND DANGEROUS CARDIOVASCULAR RISK FACTOR

Sleep apnea involves almost one billion individuals throughout the world, including 40 million Americans. Of major medical concern is the fact that the prevalence of sleep apnea is significantly increasing due to the epidemic of obesity, physical inactivity, and diabetes mellitus which are important risk factors for the development and persistence of sleep apnea in individuals. Sleep apnea is characterized by multiple episodes of apnea or hypopnea during sleep, which cause nocturnal arousals, gasping for breath during the night, daytime sleepiness, irritability, forgetfulness, fatigue and recurrent headaches. Obstructive sleep apnea occurs when upper airway obstruction occurs in an individual during sleep with absent or markedly reduced airflow in the presence of continued activity of inspiratory thoracic and diaphragmatic muscles. Central sleep apnea is defined as the absence or the significant reduction of naso-oral airflow due to the withdrawal during sleep of ponto-medullary respiratory center stimulation of the nerves of the inspiratory thoracic and diaphragmatic muscles and absence of contraction of these muscles during apnea. Complex sleep apnea occurs when an individual exhibits characteristics of both obstructive and central sleep apnea. The severity of sleep apnea is measured by polysomnography and the apnea hypopnea index (AHI), which is the average number of apneas and hypopneas per hour of sleep measured by polysomnography. Sleep apnea is mild if the AHI is 5-14/hour with no or mild symptoms, moderate if the AHI is 15 to 30/hour with occasional daytime sleepiness, and severe if the AHI is >30/hour with frequent daytime sleepiness that interferes with the normal activities of daily life. Chronic sleep apneas and hypopneas followed by compensatory hyperpneas are associated with significant adverse cardiovascular consequences including: 1) recurrent hypoxemia and hypercarbia; 2) Increased sympathetic nerve activity and decreased parasympathetic nerve activity; 3) oxidative stress and vascular endothelial dysfunction; and 4) cardiac remodeling and cardiovascular disease. Moderate or severe sleep apnea significantly increases the risk of coronary artery disease, congestive heart failure, cerebral vascular events (strokes), and cardiac dysrhythmias, and also increase the morbidity and mortality of these diseases. Nevertheless, sleep apnea is currently underdiagnosed and untreated in many individuals due to the challenges in the prediction and detection of sleep apnea and a lack of well-defined optimal treatment guidelines. Chronic continuous positive airway pressure for ≥4 hours/night for >70% of nights is beneficial in the treatment of patients with sleep apnea. CPAP Improves sleep quality, reduces the AHI, augments cardiac output and increases oxygen delivery to brain and heart, reduces resistant hypertension, decreases cardiac dysrhythmias, and reduces daytime sleepiness. The present article discusses the diagnosis of obstructive sleep apnea, central sleep apnea, and complex apnea. Thereafter the important pathophysiologic mechanisms in sleep apnea and the relationship of these pathophysiologic mechanics to atherosclerotic vascular disease are reviewed. Guidelines are then provided for the treatment of mild, moderate and severe sleep apnea In order to reduce the cardiovascular morbidity and mortality caused by sleep apnea and facilitate the diagnosis and the long-term, effective treatment of sleep apnea in patients, the close cooperation is necessary of cardiovascular specialists, pulmonary specialists, and respiratory therapy/ rehabilitation specialists.

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

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

Adherence to CPAP Therapy in Obstructive Sleep Apnea: A Prospective Study on Quality of Life and Determinants of Use

Obstructive sleep apnea (OSA) often goes unrecognized despite common symptoms, such as excessive daytime sleepiness, fatigue, and impaired quality of life (QoL). Continuous positive airway pressure (CPAP) is the gold standard treatment for OSA, but optimal daily usage and time needed for observable effects remain unclear. This study aimed to investigate the short-term effects of CPAP on daytime sleepiness and QoL in patients with severe OSA. Medical records were collected from 87 patients with severe OSA who initiated CPAP therapy. Also, validated questionnaires were used before and after one month of CPAP to analyze QoL-the Calgary Sleep Apnea Quality of Life Index (SAQLI), the Cues to CPAP Use Questionnaire (CCUQ), and daytime sleepiness-the Epworth Sleepiness Scale (ESS). Multiple regression analysis was conducted to identify predictors of CPAP usage. Of the total participants aged 55.6 ± 12.5, 77% were males, and 62% were CPAP adherent. Reductions in daytime sleepiness (ESS) were noted, as well as improvements in both overall QoL (SAQLI) and specifically in the domains of daily functioning, social interactions, emotional well-being, and symptom perception. Important cues for CPAP usage recognized by patients were physicians' instructions and physicians' concern regarding their patients' condition. Furthermore, multiple regression revealed higher SAQLI scores and lower ESS scores as positive predictors of CPAP usage, along with lower AHI after one month of CPAP being associated with sufficient adherence.

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.

Long-term effect of obstructive sleep apnoea management on blood pressure in patients with resistant hypertension: the SARAH study

BACKGROUND

There is a close relationship between obstructive sleep apnoea (OSA) and resistant hypertension (RH). However, studies assessing the long-term effect of diagnosing and treating OSA on blood pressure (BP) control in these patients are lacking.

METHODS

To address this gap, we recruited 478 RH patients from hypertension units and followed them prospectively after they were screened for OSA through a sleep study. By performing 24-h ambulatory BP monitoring (ABPM) annually, the effect of OSA management was assessed.

RESULTS

The patients had a median (interquartile range (IQR)) age of 64.0 (57.2-69.0) years, 67% were males and most were nonsleepy, with a median (IQR) apnoea-hypopnoea index (AHI) of 15.8 (7.9-30.7) events·h-1. The median (IQR) follow-up time was 3.01 (2.93-3.12) years. At baseline, severe OSA was associated with uncontrolled BP, nocturnal hypertension and a nondipper circadian BP pattern. Moreover, these patients had higher BP values during follow-up than did patients in the other groups. However, among patients with moderate and severe OSA, the management of sleep disordered breathing, including the implementation of continuous positive airway pressure treatment, was associated with a reduction in 24-h ABPM parameters, especially night-time BP values, at the 1-year follow-up. These benefits were attenuated over time and only subjects with severe OSA maintained an ABPM night-time reduction at 3 years. Furthermore, clinical variables such as uncontrolled BP, sex and age showed a predictive value for the BP response at 1 year of follow-up.

CONCLUSION

A favourable long-term decrease in BP was detected by diagnosing and treating OSA in a cohort of RH patients from hypertension units, but over time this decrease was only partially maintained in severe OSA patients.

Obstructive sleep apnea and hypertension; critical overview

Obstructive sleep apnea (OSA) and hypertension are two important modifiable risk factors for cardiovascular disease and mortality. Numerous studies have highlighted the interplay between these two conditions. We provide a critical review of the current literature on the role of the OSA as a risk factor for hypertension and its effect on blood pressure (BP). We discuss several key topics: the effect of OSA on nocturnal BP, BP response to continuous positive airway pressure (CPAP) treatment, CPAP effect on BP in refractory hypertension, the role of OSA in BP variability (BPV), and maladaptive cardiac remodeling mediated by OSA's effect on BP. Finally, we discuss the unique aspects of ethnicity and social determinants of health on OSA with a focus on Asian populations and the disparity in BP control and cardiovascular outcomes.

The effect of PAP on UACR and metabolic indexes in patients with MS and OSAHS

PURPOSE

To investigate the effects of positive airway pressure (PAP) device on urinary albumin to creatinine ratio (UACR) and metabolic indexes in patients with metabolic syndrome (MS) and obstructive sleep apnea-hypopnea syndrome (OSAHS).

METHODS

This study is a retrospective cohort study. Grouped according to whether to use PAP treatment, there were 25 cases in the PAP group and 44 cases in the no OSAHS treatment group. The PAP group received positive airway pressure device and routine treatment of MS. The no OSAHS treatment group received routine treatment of OSAHS and MS. The treatment period is 3 months.

RESULTS

1. The PAP group demonstrated significant reductions in Body Mass Index (BMI), Waist circumference (WC), Neck circumference (NC), Visceral fat area (VFA), Fasting C peptide (FCP), high-sensitivity C-reactive protein (hs-CRP), and UACR compared to the no OSAHS treatment group, with significant differences (P all <0.05). Among them, the UACR in the PAP group decreased significantly (from 86.05(52.55,131.61)mg/g to 16.76(8.70,25.12)mg/g, P<0.001). 2. Linear regression analysis using the decrease in UACR values as the dependent variable demonstrated a positive linear relationship with the decrease in BMI, VFA, fasting insulin (FINS), and homeostasis model assessment of insulin resistance (HOMA-IR). Furthermore, multiple linear regression analysis indicated that the decrease in VFA (B=0.537 [95% confidence interval, 0.084 to 0.989]; P = 0.021) and HOMA-IR (B=1.000 [95% confidence interval, 0.082 to 1.917]; P = 0.033) values independently correlated with decrease in UACR values.

CONCLUSIONS

PAP treatment can reduce UACR in patients with MS and OSAHS, and has the effect of improving metabolic disorders. The decrease of UACR in patients may be related to the decrease of visceral fat and the improvement of insulin resistance.

Prevalence and regional distribution of obstructive sleep apnea in Canada: Analysis from the Canadian Longitudinal Study on Aging

OBJECTIVES

Obstructive sleep apnea (OSA) is a common chronic condition that is often undiagnosed or diagnosed after many years of symptoms and has an impact on quality of life and several health factors. We estimated the Canadian national prevalence of OSA using a validated questionnaire and physical measurements in participants in the Canadian Longitudinal Study on Aging (CLSA).

METHODS

The method used individual risk estimation based upon the validated STOP-BANG scale developed for OSA. This stratified population sample spans Canada to provide regional estimates.

RESULTS

In this sample of adults aged 45 to 85 years old, the overall prevalence in 2015 of combined moderate and severe OSA in the 51,337 participants was 28.1% (95% confidence intervals, 27.8‒28.4). The regional prevalence varied statistically between Atlantic Canada and Western Canada (p < 0.001), although clinically the variations were limited. The provincial prevalence for moderate and severe OSA ranged from 27.5% (New Brunswick and British Columbia) to 29.1% (Manitoba). Body mass index (BMI) was the dominant determinant of the variance between provinces (β = 0.33, p < 0.001). Only 1.2% of participants had a clinical diagnosis of OSA.

CONCLUSION

The great majority (92.9%) of the participants at high risk of OSA were unrecognized and had no clinical diagnosis of OSA.

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.

Effect of obstructive sleep apnea on postoperative delirium: a system review and meta-analysis

PURPOSE

To investigate the impact of obstructive sleep apnea (OSA) on postoperative delirium (PD), and evaluate the effectiveness of positive airway pressure (PAP) therapy on PD among OSA patients.

METHODS

We systematically searched Embase, Cochrane Library and PubMed databases from their establishment to November 27, 2022. A random-effects approach was employed to determine aggregated results. Subgroup and sensitivity analyses were carried out to investigate heterogeneity.

RESULTS

Sixteen eligible studies were included in the analysis. Thirteen studies revealed that OSA significantly elevated the likelihood of developing PD (OR = 1.71; 95%CI = 1.17 to 2.49; p = 0.005). Subgroup analysis according to delirium assessment scales showed that OSA did not exhibit an association with the incidence of PD assessed by the Confusion Assessment Method-Intensive Care Unit (OR = 1.14; 95%CI = 0.77 to 1.67; p = 0.51) but enhanced the likelihood of developing PD evaluated with other measurement scales (OR = 2.15; 95%CI = 1.44 to 3.19; p = 0.0002). Three additional studies explored the impact of PAP treatment on PD among OSA individuals, indicating no significant reduction in PD incidence with PAP use (OR = 0.58; 95%CI = 0.13 to 2.47; p = 0.46).

CONCLUSIONS

OSA may not be a risk factor for PD in critically ill patients in the intensive care unit, but may increase the likelihood of developing PD among individuals receiving regular care in the ward postoperatively. The efficacy of PAP therapy in decreasing PD incidence among OSA patients remains debatable.

Revolutionizing Sleep Health: The Emergence and Impact of Personalized Sleep Medicine

Personalized sleep medicine represents a transformative shift in healthcare, emphasizing individualized approaches to optimizing sleep health, considering the bidirectional relationship between sleep and health. This field moves beyond conventional methods, tailoring care to the unique physiological and psychological needs of individuals to improve sleep quality and manage disorders. Key to this approach is the consideration of diverse factors like genetic predispositions, lifestyle habits, environmental factors, and underlying health conditions. This enables more accurate diagnoses, targeted treatments, and proactive management. Technological advancements play a pivotal role in this field: wearable devices, mobile health applications, and advanced diagnostic tools collect detailed sleep data for continuous monitoring and analysis. The integration of machine learning and artificial intelligence enhances data interpretation, offering personalized treatment plans based on individual sleep profiles. Moreover, research on circadian rhythms and sleep physiology is advancing our understanding of sleep's impact on overall health. The next generation of wearable technology will integrate more seamlessly with IoT and smart home systems, facilitating holistic sleep environment management. Telemedicine and virtual healthcare platforms will increase accessibility to specialized care, especially in remote areas. Advancements will also focus on integrating various data sources for comprehensive assessments and treatments. Genomic and molecular research could lead to breakthroughs in understanding individual sleep disorders, informing highly personalized treatment plans. Sophisticated methods for sleep stage estimation, including machine learning techniques, are improving diagnostic precision. Computational models, particularly for conditions like obstructive sleep apnea, are enabling patient-specific treatment strategies. The future of personalized sleep medicine will likely involve cross-disciplinary collaborations, integrating cognitive behavioral therapy and mental health interventions. Public awareness and education about personalized sleep approaches, alongside updated regulatory frameworks for data security and privacy, are essential. Longitudinal studies will provide insights into evolving sleep patterns, further refining treatment approaches. In conclusion, personalized sleep medicine is revolutionizing sleep disorder treatment, leveraging individual characteristics and advanced technologies for improved diagnosis, treatment, and management. This shift towards individualized care marks a significant advancement in healthcare, enhancing life quality for those with sleep disorders.

Effect of Continuous Positive Airway Pressure on Blood Pressure in Patients with Resistant Hypertension and Obstructive Sleep Apnea: An Updated Meta-analysis

PURPOSE OF REVIEW

The effect of continuous positive airway pressure (CPAP) on resistant hypertension in patients at high risk with obstructive sleep apnea (OSA) needs further investigation. We aimed to determine the effect of CPAP on blood pressure in patients with resistant hypertension and OSA. Databases including PubMed, EMBASE, MEDLINE, the Cochrane Library, and CMB were searched. Data were pooled using a random-effects or fixed-effects model to derive weighted mean differences (WMDs) and 95% confidence intervals (CIs).

RECENT FINDINGS

A total of 12 trials and 718 participants were included. Compared with control, CPAP significantly reduced 24-h systolic blood pressure (SBP) (WMD: - 5.92 mmHg [ - 8.72, - 3.11]; P＜0.001), 24-h diastolic blood pressure (DBP) (WMD: - 4.44 mmHg [- 6.26 , - 2.62]; P  ＜0.001),   daytime SBP (WMD: - 5.76 mmHg [ - 9.16,  - 2.36]; P ＜0.001),  daytime DBP (WMD: - 3.92 mmHg [- 5.55,  - 2.30];  nighttime SBP (WMD: - 4.87 mmHg [ - 7.96 ,  - 1.78]; P = 0.002), and nighttime DBP (WMD: - 2.05 mmHg [- 2.99,  - 1.11]; P＜0.001) in patients with resistant hypertension and OSA. CPAP improved the blood pressure both in the short (＜3 months) and long term (≥ 3  months). No significant impact on mean heart rate was noted (WMD: -2.76 beats per min [- 7.50, 1.97]; P = 0.25). CPAP treatment was associated with BP reduction in patients with resistant hypertension and 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.

Effects of different treatments on metabolic syndrome in patients with obstructive sleep apnea: a meta-analysis

Background

Obstructive sleep apnea (OSA) and metabolic syndrome (MetS) often coexist, and the causal relationship between them is not yet clear; treatments for OSA include continuous positive airway pressure (CPAP), mandibular advancement device (MAD), surgery, and lifestyle intervention and so on. However, the effects of different treatments on metabolic syndrome in OSA patients are still under debate.

Objectives

Review the effects of different treatments on metabolic syndrome in OSA patients by meta-analysis.

Methods

we searched articles in PubMed, Embase, Cochrane Library, CNKI, CBM, and Wanfang data from database construction to Feb. 2024.RevMan5.4 and Stata software were used to conduct a meta-analysis of 22 articles.

Results

A total of 22 articles were finally included. The results showed that CPAP treatment could reduce the prevalence of metabolic syndrome in OSA patients in randomized controlled trials (RCTs) (RR = 0.82 [95% CI, 0.75 to 0.90]; p < 0.01) and single-arm studies (RR = 0.73 [95% CI, 0.63 to 0.84]; p < 0.01). As for metabolic syndrome components, CPAP treatment reduces blood pressure, fasting glucose (FG), triglycerides (TG), and waist circumference (WC) but can't affect high-density lipoprotein cholesterol (HDL-C) levels. Lifestyle intervention could significantly reduce the prevalence of metabolic syndrome in OSA patients (RR = 0.60 [95% CI, 0.48 to 0.74]; p < 0.01) and can lower blood pressure, fasting glucose, and waist circumference but can't affect the lipid metabolism of OSA patients. Upper airway surgery can only reduce TG levels in OSA patients (MD = -0.74 [95% CI, -1.35 to -0.13]; p = 0.02) and does not affect other components of metabolic syndrome. There is currently no report on the impact of upper airway surgery on the prevalence of metabolic syndrome. No study has reported the effect of MAD on metabolic syndrome in OSA patients.

Conclusion

We confirmed that both CPAP and lifestyle intervention can reduce the prevalence of MetS in OSA patients. CPAP treatment can lower blood pressure, fasting glucose, waist circumference, and triglyceride levels in OSA patients. Lifestyle intervention can lower blood pressure, fasting glucose, and waist circumference in OSA patients. Upper airway surgery can only reduce TG levels in OSA patients.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022326857.

Nocturnal oxygen therapy in obstructive sleep apnoea: a systematic review and meta-analysis

Obstructive sleep apnoea is characterised by recurrent reduction of airflow during sleep leading to intermittent hypoxia. Continuous positive airway pressure is the first-line treatment but is limited by poor adherence. Nocturnal oxygen therapy may be an alternative treatment for obstructive sleep apnoea but its effects remain unclear. This meta-analysis evaluates the effects of nocturnal oxygen therapy on both obstructive sleep apnoea severity and blood pressure.A literature search was performed based on the Preferred Reporting Items for Systematic Review and Meta-analysis guidelines. Peer-reviewed, randomised studies that compared the effect of nocturnal oxygen therapy to sham in obstructive sleep apnoea patients were included. The main outcomes were the apnoea-hypopnoea index and systolic and diastolic blood pressure.The search strategy yielded 1295 citations. Nine studies with 502 participants were included. When nocturnal oxygen therapy was compared to sham/air, it significantly reduced the apnoea-hypopnoea index (mean difference (MD) -15.17 events·h-1, 95% CI -19.95- -10.38 events·h-1, p<0.00001). Nocturnal oxygen therapy had no significant effect on blood pressure at follow-up without adjustment for baseline values, but did, where available, significantly attenuate the change in blood pressure from baseline to follow-up for both systolic blood pressure (MD -2.79 mmHg, 95% CI -5.45- -0.14 mmHg, p=0.040) and diastolic blood pressure (MD -2.20 mmHg, 95% CI -3.83- -0.57 mmHg, p=0.008).Nocturnal oxygen therapy reduced the apnoea-hypopnoea index severity and the change in (but not absolute) systolic and diastolic blood pressure, compared to sham. This suggests that nocturnal oxygen therapy may be a treatment option for obstructive sleep apnoea. Further studies with longer-term follow-up and standardised measurements are needed.

Management of nocturnal hypertension: An expert consensus document from Chinese Hypertension League

Nocturnal hypertension is highly prevalent among Chinese and Asian populations, which is mainly attributed to high salt intake and high salt sensitivity. Nocturnal hypertension increases the risk of cardiovascular and all-cause mortality, independent of daytime blood pressure (BP). However, it can usually be detected by 24-h ambulatory BP monitoring, rather than routine office or home BP measurement, thus is often underdiagnosed in clinical practice. Currently, no specific guidance is available for the management of nocturnal hypertension in China or worldwide. Experts from the Chinese Hypertension League summarized the epidemiologic and pathophysiologic characteristics and clinical phenotype of nocturnal hypertension and provided consensus recommendations on optimal management of nocturnal hypertension, with the goal of maximally reducing the cardiovascular disease risks. In this consensus document, 24-h ABPM is recommended for screening and diagnosis of nocturnal hypertension, especially in the elderly, patients with diabetes, chronic kidney diseases, obstructive sleep apnea and other conditions prone to high nocturnal BP. Lifestyle modifications including salt intake restriction, exercise, weight loss, sleep improvement, and mental stress relief are recommended. Long-acting antihypertensive medications are preferred for nocturnal and 24-h BP control. Some newly developed agents, renal denervation, and other device-based therapy on nocturnal BP reduction are evaluated.

The Value of Implementing a Digital Approach in the Obstructive Sleep Apnoea Patient Pathway: A Spanish Example

Introduction

Continuous positive airway pressure (CPAP) is the gold standard therapy for obstructive sleep apnoea (OSA). However, non-adherence is common and costly. The COVID-19 pandemic required the use of novel solutions to ensure service provision and quality of care. This retrospective analysis determined the impact and value of a digital versus standard pathway for the management of OSA in Spain.

Methods

A time-driven activity-based costing approach was applied to OSA management over 1 year using a standard or digital pathway. The standard pathway included face-to-face appointments at the time of diagnosis, then after 1-3 months and every 6 months thereafter. The digital pathway had fewer face-to-face appointments and utilised telemonitoring. A cost analysis was performed to determine the per-patient cost per healthcare professional (HCP) for a digital pathway for therapy implementation and follow-up compared with the standard pathway.

Results

Compared with the standard pathway, the digital pathway decreased the waiting list time from 18 to 2 months, the overall pathway time from 12 to 6 months, HCP cost per patient from €95 to €85, and number of hospital appointments per patient from 6 to 3.1. Furthermore, CPAP device usage improved from 5.7 to 6.3 h/night and the proportion of individuals defined as adherent increased from 79% to 91%.

Conclusions

Implementation of digital processes using available technology reduced HCP time and costs, and improved adherence to CPAP in people with OSA. Greater utilisation of a digital pathway could improve access to therapy, allow personalised patient management, and facilitate better clinical outcomes.

Long-term health outcomes for patients with obstructive sleep apnea: placing the Agency for Healthcare Research and Quality report in context-a multisociety commentary

This multisociety commentary critically examines the Agency for Healthcare Research and Quality (AHRQ) final report and systematic review on long-term health outcomes in obstructive sleep apnea. The AHRQ report was commissioned by the Centers for Medicare & Medicaid Services and particularly focused on the long-term patient-centered outcomes of continuous positive airway pressure, the variability of sleep-disordered breathing metrics, and the validity of these metrics as surrogate outcomes. This commentary raises concerns regarding the AHRQ report conclusions and their potential implications for policy decisions. A major concern expressed in this commentary is that the AHRQ report inadequately acknowledges the benefits of continuous positive airway pressure for several established, long-term clinically important outcomes including excessive sleepiness, motor vehicle accidents, and blood pressure. While acknowledging the limited evidence for the long-term benefits of continuous positive airway pressure treatment, especially cardiovascular outcomes, as summarized by the AHRQ report, this commentary reviews the limitations of recent randomized controlled trials and nonrandomized controlled studies and the challenges of conducting future randomized controlled trials. A research agenda to address these challenges is proposed including study designs that may include both high quality randomized controlled trials and nonrandomized controlled studies. This commentary concludes by highlighting implications for the safety and quality of life for the millions of people living with obstructive sleep apnea if the AHRQ report alone was used by payers to limit coverage for the treatment of obstructive sleep apnea while not considering the totality of available evidence.

CITATION

Patil SP, Billings ME, Bourjeily G, et al. Long-term health outcomes for patients with obstructive sleep apnea: placing the Agency for Healthcare Research and Quality report in context-a multisociety commentary. J Clin Sleep Med. 2024;20(1):135-149.

Impact of CPAP Therapy on the Autonomic Nervous System

Obstructive sleep apnea (OSA) is a significant risk factor for cardiovascular disease (CVD) with increasing prevalence. An important mechanism of CVD development is a dysregulation of the autonomic nervous system (ANS). This prospective and controlled cohort study aimed to investigate ANS function in OSA including the response to long-term continuous positive airway pressure (CPAP) therapy by analyzing 24 h Holter electrocardiogram and 24 h Holter ambulatory blood pressure recording parameters. The study enrolled 57 patients who were newly diagnosed with severe OSA. After 6 months of CPAP therapy, 37 patients had a good therapy adherence (usage of CPAP device >4 h per night), and their data were analyzed. The difference in nocturnal diastolic blood pressure values before and after CPAP therapy reached statistical significance (76 (68-84) vs. 74 (63-80) mmHg, p = 0.0439). Lower nocturnal values after CPAP therapy of SDNN (101.5 vs. 95 ms, p = 0.0492) and RMSSD (29.5 vs. 26 ms, p = 0.0193) were found. An increase in diurnal spectral power (1742 vs. 2112 ms2, p = 0.0282) and a decrease in nocturnal spectral power (3256 vs. 2124 ms2, p = 0.0097), nocturnal VLF band (2493 vs. 1485.4 ms2, p = 0.0176), nocturnal LF band (638.7 vs. 473 ms2, p = 0.0097), and nocturnal HF band (234.9 vs. 135.7 ms2, p = 0.0319) was found. The results showed an imbalance of the ANS with a sympathetic predominance, especially during the night hours and in those with arterial hypertension. The impact of CPAP therapy on the improvement in ANS parameters was more pronounced at night, in men, and those with arterial hypertension.

Adaptive responses to chronic intermittent hypoxia: contributions from the European Sleep Apnoea Database (ESADA) Cohort

Obstructive sleep apnoea (OSA) is a common disease in the general population, and is associated with increased cardiovascular risk and several comorbidities. Obesity favours upper airway collapsibility, but other pathophysiological traits have been identified, i.e. upper airway muscle activity, modulation of the respiratory drive, and the arousal threshold. OSA causes chronic intermittent hypoxia, inflammatory activation and autonomic imbalance with diurnal and nocturnal sympathetic hyperactivity. Disentangling so many components to investigate the pathogenesis of OSA's consequences is very hard clinically. However, albeit imperfect, clinical medicine constitutes a major source of inspiration for basic research, and a mutual exchange of information is essential between clinicians and physiologists to improve our understanding of disease states. OSA is no exception, and this narrative review will summarize the results of clinical studies performed over the years by the European Sleep Apnoea Database (ESADA) Study Group, to explore the variables linked to markers of intermittent hypoxia as opposed to the traditional assessment of OSA severity based on the frequency of respiratory events during sleep (the Apnoea Hypopnoea Index). The results of the clinical studies indicate that intermittent hypoxia variables are associated with several comorbidities, although evidence of a cause-effect relationship is still missing in many cases. It is also possible that adaptive rather than maladaptive responses could be evoked by intermittent hypoxia. The intensity, duration and frequency of intermittent hypoxia episodes causing adaptive rather than maladaptive responses, and their clinical implications, deserve further investigation.

Long non-coding RNA FKSG29 regulates oxidative stress and endothelial dysfunction in obstructive sleep apnea

Altered expressions of pro-/anti-oxidant genes are known to regulate the pathophysiology of obstructive sleep apnea (OSA).We aim to explore the role of a novel long non-coding (lnc) RNA FKSG29 in the development of intermittent hypoxia with re-oxygenation (IHR)-induced endothelial dysfunction in OSA. Gene expression levels of key pro-/anti-oxidant genes, vasoactive genes, and the FKSG29 were measured in peripheral blood mononuclear cells from 12 subjects with primary snoring (PS) and 36 OSA patients. Human monocytic THP-1 cells and human umbilical vein endothelial cells (HUVEC) were used for gene knockout and double luciferase under IHR exposure. Gene expression levels of the FKSG29 lncRNA, NOX2, NOX5, and VEGFA genes were increased in OSA patients versus PS subjects, while SOD2 and VEGFB gene expressions were decreased. Subgroup analysis showed that gene expression of the miR-23a-3p, an endogenous competitive microRNA of the FKSG29, was decreased in sleep-disordered breathing patients with hypertension versus those without hypertension. In vitro IHR experiments showed that knock-down of the FKSG29 reversed IHR-induced ROS overt production, early apoptosis, up-regulations of the HIF1A/HIF2A/NOX2/NOX4/NOX5/VEGFA/VEGFB genes, and down-regulations of the VEGFB/SOD2 genes, while the protective effects of FKSG29 knock-down were abolished by miR-23a-3p knock-down. Dual-luciferase reporter assays confirmed that FKSG29 was a sponge of miR-23a-3p, which regulated IL6R directly. Immunofluorescence stain further demonstrated that FKSGH29 knock-down decreased IHR-induced uptake of oxidized low density lipoprotein and reversed IHR-induced IL6R/STAT3/GATA6/ICAM1/VCAM1 up-regulations. The findings indicate that the combined RNA interference may be a novel therapy for OSA-related endothelial dysfunction via regulating pro-/anti-oxidant imbalance or targeting miR-23a-IL6R-ICAM1/VCAM1 signaling.

Adherence to CPAP Treatment and the Risk of Recurrent Cardiovascular Events: A Meta-Analysis

Importance

The effect of continuous positive airway pressure (CPAP) on secondary cardiovascular disease prevention is highly debated.

Objective

To assess the effect of CPAP treatment for obstructive sleep apnea (OSA) on the risk of adverse cardiovascular events in randomized clinical trials.

Data Sources

PubMed (MEDLINE), EMBASE, Current Controlled Trials: metaRegister of Controlled Trials, ISRCTN Registry, European Union clinical trials database, CENTRAL (Cochrane Central Register of Controlled Trials), and ClinicalTrials.gov databases were systematically searched through June 22, 2023.

Study Selection

For qualitative and individual participant data (IPD) meta-analysis, randomized clinical trials addressing the therapeutic effect of CPAP on cardiovascular outcomes and mortality in adults with cardiovascular disease and OSA were included.

Data Extraction and Synthesis

Two reviewers independently screened records, evaluated potentially eligible primary studies in full text, extracted data, and cross-checked errors. IPD were requested from authors of the selected studies (SAVE [NCT00738179], ISAACC [NCT01335087], and RICCADSA [NCT00519597]).

Main Outcomes and Measures

One-stage and 2-stage IPD meta-analyses were completed to estimate the effect of CPAP treatment on risk of recurrent major adverse cardiac and cerebrovascular events (MACCEs) using mixed-effect Cox regression models. Additionally, an on-treatment analysis with marginal structural Cox models using inverse probability of treatment weighting was fitted to assess the effect of good adherence to CPAP (≥4 hours per day).

Results

A total of 4186 individual participants were evaluated (82.1% men; mean [SD] body mass index, 28.9 [4.5]; mean [SD] age, 61.2 [8.7] years; mean [SD] apnea-hypopnea index, 31.2 [17] events per hour; 71% with hypertension; 50.1% receiving CPAP [mean {SD} adherence, 3.1 {2.4} hours per day]; 49.9% not receiving CPAP [usual care], mean [SD] follow-up, 3.25 [1.8] years). The main outcome was defined as the first MACCE, which was similar for the CPAP and no CPAP groups (hazard ratio, 1.01 [95% CI, 0.87-1.17]). However, an on-treatment analysis by marginal structural model revealed a reduced risk of MACCEs associated with good adherence to CPAP (hazard ratio, 0.69 [95% CI, 0.52-0.92]).

Conclusions and Relevance

Adherence to CPAP was associated with a reduced MACCE recurrence risk, suggesting that treatment adherence is a key factor in secondary cardiovascular prevention in patients with OSA.

Relationship between Self-reported Sleepiness and Positive Airway Pressure Treatment Adherence in Obstructive Sleep Apnea

Rationale: Positive airway pressure (PAP) is the first-choice treatment for obstructive sleep apnea (OSA). However, its real-world effectiveness is often questioned because of usage issues. The relationship between patient sleepiness and PAP usage has been assessed in relatively small and selected populations within the research context. Objectives: To assess the impact of patient-reported sleep outcomes, particularly self-reported sleepiness and its change during therapy, on PAP usage in the real-world setting. Methods: Deidentified data for U.S.-based patients receiving PAP therapy were examined. Eligible patients were registered in the myAir app and provided self-reported sleepiness at baseline and after 7, 14, 21, and 28 days of PAP between November 2019 and April 2020. Results: A total of 95,397 registered patients met all eligibility criteria and were included in the analysis (mean age, 49.6 ± 13.0 yr; 61.6% male). Daytime sleepiness was the most common reason for PAP therapy initiation (57.1% of patients), and 42.2% of all patients had self-reported moderate to severe OSA. Self-reported sleepiness improved with PAP therapy in most patients over the assessment period, with 62.1% of patients reporting "no" or "slight" sleepiness at Day 28. There was a dose-dependent association between improvement in self-reported sleepiness at Day 28 and PAP usage, and this finding was maintained at Day 360. Self-reported sleepiness at Day 28 was associated with achieving U.S. Centers for Medicare & Medicaid Services compliance at 90 days (approximately 90% for those with no or slight sleepiness vs. <70% for those with residual very or extreme sleepiness); average daily PAP usage over 360 days was ⩾5.0 and ⩽3.7 hours, respectively, for those with no or slight versus very or extreme sleepiness. Conclusions: This study demonstrates the feasibility of capturing patient-reported outcomes via a digital platform. Patient-reported outcomes appear to be associated with PAP usage, especially self-reported sleepiness and its response to therapy. Capturing patient-reported outcomes using digital solutions during the course of treatment has the potential to enhance patient outcomes by providing actionable insights.

Evaluation and Performance of a Positive Airway Pressure Device (CPAP-AirFlife™): A Randomized Crossover Non-Inferiority Clinical Study in Normal Subjects

Background and Objectives: During the COVID-19, the demand for non-invasive ventilatory support equipment significantly increased. In response, a novel non-invasive ventilatory support model called CPAP-AirFlife™ was developed utilizing existing technologies. This model offers technological advantages, including an aerosol-controlled helmet suitable for high-risk environments such as ambulances. Additionally, it is cost-effective and does not require medical air, making it accessible for implementation in low-level hospitals, particularly in rural areas. This study aimed to assess the efficacy of CPAP-AirFlife™ by conducting a non-inferiority comparison with conventional ventilation equipment used in the Intensive Care Unit. Materials and Methods: A clinical study was conducted on normal subjects in a randomized and sequential manner. Parameters such as hemoglobin oxygen saturation by pulse oximetry, exhaled PCO2 levels, vital signs, and individual tolerance were compared between the CPAP-AirFlife™ and conventional equipment. The study population was described in terms of demographic characteristics and included in the analysis. Results: It was shown that the CPAP-AirFlife™ was not inferior to conventional equipment in terms of efficacy or tolerability. Hemoglobin oxygen saturation levels, exhaled PCO2 levels, vital signs, and individual tolerance did not significantly differ between the two models. Conclusions: The findings suggest that CPAP-AirFlife™ is a practical and cost-effective alternative for non-invasive ventilatory support. Its technological advantages, including the aerosol-controlled helmet, make it suitable for high-risk environments. The device's accessibility and affordability make it a promising solution for implementation in low-level hospitals, particularly in rural areas. This study supports using CPAP-AirFlife™ as a practical option for non-invasive ventilatory support, providing a valuable contribution to respiratory care during the COVID-19 pandemic and beyond.

Endotyping, phenotyping and personalised therapy in obstructive sleep apnoea: are we there yet?

Obstructive sleep apnoea (OSA) was traditionally thought to be mainly caused by obesity and upper airway crowding, and hence OSA management was not personalised according to particular characteristics, with most symptomatic patients receiving continuous positive airway pressure therapy. Recent advances in our understanding have identified additional potential and distinct causes of OSA (endotypes), and subgroups of patients (phenotypes) with increased risk of cardiovascular complications. In this review, we discuss the evidence to date as to whether there are distinct clinically useful endotypes and phenotypes of OSA, and the challenges to the field in moving towards delivering personalised therapy in OSA.

Forecasting of breathing events during nocturnal sleep using encoder-decoder recurrent neural network based on a sensors data of consumer smartwatches

Respiratory disorders during nocturnal sleep are the states of abnormal and difficult breathing, including snoring, hypopnea and different apnea types. Some of them have a negligible effect on health, while others can lead to a serious consequences. Therefore, the development of low-cost, portable, user-friendly devices and corresponding algorithms for diagnosis and forecasting of such events is of particular importance. In the current paper, an encoder-decoder recurrent neural network was developed for respiratory pattern forecasting. The system is based on a physiological sensors (accelerometer and photoplethysmography) data gathered from the consumer smartwatches during nocturnal sleep. The influence of the length of time series in the encoder part (available history for forecasting), and the length of time series at the output of decoder (forecasting length) is studied. The average achieved f1 score and Cohen's Kappa agreement of the proposed model varies in the range from 0.35 to 0.5 and from 0.25 to 0.4, respectively, depending on forecasting length. The efficiency of the forecasting largely depends on the model complexity, presence or absence of respiration events in the encoder part, and forecasting length.Clinical Relevance- Results of the current paper may be used for the development of the respiration events screening tool based on a wearable devices sensors data.

A Narrative Review of the Association of Obstructive Sleep Apnea with Hypertension: How to Treat Both When They Coexist?

Hypertension (HT) is a worldwide public health issue and an essential risk factor for cardiovascular and cerebrovascular diseases. Obstructive sleep apnea (OSA) is a condition characterized by recurrent episodes of apnea and hypopnea as a consequence of partial or complete obstruction of the upper airways due to anatomic and/or functional disturbances. There is mounting evidence of a relationship between OSA and HT. In patients with OSA, HT is predominantly nocturnal and characterized by high diastolic blood pressure and usually by a nondipping pattern. Optimizing the blood pressure control is recommended in the current guidelines as the first treatment option in hypertensive patients with OSA. Continuous positive airway pressure (CPAP) therapy may reduce blood pressure, albeit only slightly as a stand-alone treatment. CPAP, as an add-on treatment to antihypertensive medication, appears to be an efficient treatment modality when both conditions coexist. This narrative review aims to summarize the current perspectives on the association of OSA with HT and the treatment options available for adults with OSA-related HT.

Effects of Antihypertensive Treatment on Left and Right Ventricular Global Longitudinal Strain and Diastolic Parameters in Patients with Hypertension and Obstructive Sleep Apnea: Randomized Clinical Trial of Chlorthalidone plus Amiloride vs. Amlodipine

Hypertension is highly prevalent in patients with obstructive sleep apnea (OSA), and fluid retention with its nighttime rostral distribution is one potential mechanism. We tested whether or not diuretics differ from amlodipine in their impact on echocardiographic parameters. Patients with moderate OSA and hypertension were randomized to receive diuretics (chlorthalidone plus amiloride) or amlodipine daily for 8 weeks. We compared their effects on left and right ventricular global longitudinal strain (LV-GLS and RV-GLS, respectively), on LV diastolic parameters, and on LV remodeling. In the 55 participants who had echocardiographic images feasible for strain analysis, all echocardiographic parameters were within normal ranges. After 8 weeks, the 24 h blood pressure (BP) reduction values were similar, while most echocardiographic metrics were kept unchanged, except for LV-GLS and LV mass. In conclusion, the use of diuretics or amlodipine had small and similar effects on echocardiographic parameters in patients with moderate OSA and hypertension, suggesting that they do not have important effects on mediating the interaction between OSA and hypertension.

Effects of telemedicine-based follow-up management on adults with obstructive sleep apnea: A systematic review and meta-analysis

OBJECTIVES

This meta-analysis aimed to investigate the effects of telemedicine-based follow-up management on adults with obstructive sleep apnea.

METHODS

Publications were searched in the Cochrane Library, PubMed, Scopus, Web of Science and Embase. Studies were selected according to the predefined screening criteria, and their qualities were assessed by the Revised Cochrane risk-of-bias tool for randomized trials. The statistical analyses were performed using Stata12.0 software. It was registered in PROSPERO with the number: CRD42021276414.

RESULTS

A total of 33 articles with 8,689 participants were included. Telemedicine-based follow-up management improved average daily continuous positive airway pressure usage by 36 min (weighted mean difference:0.61;95% confidence interval: 0.39 to 0.83), and the percentage of days with continuous positive airway pressure usage more than four hours by 10.67% in obstructive sleep apnea patients. The meta-analysis of good continuous positive airway pressure compliance showed telemedicine-based follow-up management did not lead to good continuous positive airway pressure compliance (odds ratio: 1.13;95% confidence interval: 0.72 to 1.76). The pooled mean difference of sleep quality was 0.15 (standardized mean difference:0.15; 95% confidence interval: -0.03 to 0.32), and daytime sleepiness was -0.26 (weighted mean difference: -0.26;95% confidence interval: -0.79 to 0.28). The pooled mean difference of apnea hypopnea index was -0.53 (95% confidence interval: -3.58 to 2.51). As for the overall quality of life, the pooled mean difference was -0.25 (standardized mean difference: -0.25;95% confidence interval: -0.25 to 0.76).

CONCLUSION

Telemedicine-based follow-up management was beneficial for continuous positive airway pressure compliance of obstructive sleep apnea patients within six months. However, it could not improve sleep quality, daytime sleepiness, the severity of obstructive sleep apnea, and quality of life in obstructive sleep apnea patients compared with traditional follow-up. Moreover, it was more cost-effective, but there was no consensus on whether it would increase the workload of medical staff.

New perspective on exploring the predictive factors of blood pressure reduction during CPAP treatment in people with severe OSA and hypertension: a prospective observational study

BACKGROUND

The predictive factors of blood pressure (BP) response to continuous positive airway pressure (CPAP) in obstructive sleep apnoea (OSA) are still being explored. We aimed to assess the antihypertensive effect of CPAP considering the obstructive respiratory event-triggered BP surge profiles in 130 subjects with severe OSA and untreated hypertension.

METHODS

Nocturnal BP was monitored continuously and synchronised with polysomnography. Event-triggered BP surge profiles were studied: BP surge as the value of event-related systolic BP (SBP) elevation; BP index as the number of BP surge events of ≥10 mm Hg per hour. Patients were then divided into two groups according to the median BP index (high and low BP surge groups) and assigned to 4 weeks of CPAP. Changes in BPs and plasma biomarkers were compared. After the initial evaluation, patients with a better BP response in the high BP surge group were then followed up for the second evaluation at 24 months.

RESULTS

Overall, a modest decrease was observed in both office and asleep BPs at the 4-week follow-up; however, BPs dropped more markedly in patients in the high BP surge group than those in the low BP surge group, in both office SBP (5.3 mm Hg vs 2.2 mm Hg, p=0.003) and diastolic BP (4.0 mm Hg vs 1.2 mm Hg, p<0.001), especially the asleep SBP (9.0 mm Hg vs 2.1 mm Hg, p<0.001). For 30 cases in the high BP surge group, optimal BP control was achieved in 60.0% of patients and BP<140/90 mm Hg reached up to 83.3% after 24 months of CPAP. Linear regression revealed that BP index was significantly associated with BP decrease during CPAP treatment.

CONCLUSIONS

Our results suggested that high event-triggered BP surge was a sensitive predictor of BP response to CPAP in patients with severe OSA and untreated hypertension.

TRIAL REGISTRATION NUMBER

Clinical Trials.gov Identifier: NCT03246022; https://clinicaltrials.gov/ct2/show/NCT03246022?term=NCT+03246022&draw=2&rank=1.

Is the Gut Microbiome Implicated in the Excess Risk of Hypertension Associated with Obstructive Sleep Apnea? A Contemporary Review

Obstructive sleep apnea (OSA) is a highly prevalent sleep disorder and an established risk factor for cardiovascular diseases, including hypertension. The pathogenesis of elevated blood pressure (BP) in OSA is multifactorial, including sympathetic overdrive, vascular aberrations, oxidative stress, inflammation, and metabolic dysregulation. Among the mechanisms potentially involved in OSA-induced hypertension, the role of the gut microbiome is gaining increasing attention. Perturbations in the diversity, composition, and function of the gut microbiota have been causally linked to numerous disorders, and robust evidence has identified gut dysbiosis as a determinant of BP elevation in various populations. In this brief review, we summarize the current body of literature on the implications of altered gut microbiota for hypertension risk in OSA. Data from both preclinical models of OSA and patient populations are presented, and potential mechanistic pathways are highlighted, along with therapeutic considerations. Available evidence suggests that gut dysbiosis may promote the development of hypertension in OSA and may thus be a target for interventions aimed at attenuating the adverse consequences of OSA in relation to cardiovascular risk.

Prognostic importance of obstructive sleep apnea and CPAP treatment for cardiovascular and mortality outcomes in patients with resistant hypertension: a prospective cohort study

The prognostic importance of obstructive sleep apnea (OSA) severity and other polysomnographic parameters in patients with resistant hypertension (RHT) has never been evaluated. We aimed to assess it in a prospective cohort of 422 individuals with RHT. OSA presence/severity was ascertained by complete polysomnography (PSG) at baseline. Multivariable Cox regressions assessed the risks associated with OSA severity and other PSG parameters (apnea-hypopnea index, sleep duration, nocturnal hypoxemia and periodic limb movements) for the primary (total cardiovascular events [CVEs] and all-cause mortality) and secondary outcomes (major CVEs). In the subgroup of patients with moderate/severe OSA, the risks associated with CPAP treatment were also estimated in relation to untreated individuals. One-hundred and eighty-six participants (44%) had no/mild OSA and 236 (56%) had moderate/severe OSA, and 67 of them were CPAP-treated. Over a mean follow-up of 5 years, there were 46 CVEs (37 major ones) and 44 all-cause deaths. Neither the presence of moderate/severe or severe OSA, nor being untreated during follow-up, was associated with significant excess risks for any outcome in relation to the subgroup with no/mild OSA. Similarly, no other PSG-derived parameter predicted any adverse outcome. Otherwise, CPAP treatment was associated with non-significant risk reductions of 37% for total CVEs, 49% for major CVEs and 63% for all-cause mortality in relation to those who remained untreated during follow-up. In conclusion, the presence/severity of OSA and its related PSG parameters were not associated with worse cardiovascular/mortality prognosis in patients with RHT. However, CPAP treatment might be protective in individuals with moderate/severe OSA.

Risk of resistant hypertension associated with insomnia in patients with obstructive sleep apnea

OBJECTIVES

Patients with obstructive sleep apnea (OSA) have a high prevalence of hypertension but vary in blood pressure (BP) control, which may be partially explained by comorbid insomnia. We investigated the association of insomnia symptoms with uncontrolled BP and resistant hypertension (RH) in OSA patients.

METHODS

Between 2018 and 2021, hypertensive patients with OSA were enrolled. Information on demographic characteristics, insomnia symptoms, class of antihypertensive medications, BP control and sleep study data were collected. Controlled BP was defined as systolic BP < 140 mm Hg and diastolic BP < 90 mm Hg (BP standard); uncontrolled BP as above BP standard with use of 1-2 classes of antihypertensive medication; and RH as above BP standard with the use of ≥3 classes of antihypertensive medication (including a diuretic). Multinomial logistic regression models were fit to determine the association between insomnia symptoms and uncontrolled BP or RH (versus controlled BP) after multivariable adjustment.

RESULTS

Among the analytic sample (n = 326), 64.1% of participants had uncontrolled BP and 15.6% had RH. OSA severity was associated with a higher odds of RH (OR, 2.92; 95% CI, 1.71-4.99). After adjustment for confounders including demographic characteristics, sedative hypnotics usage, sleepiness, OSA severity and quality of life, participants experiencing insomnia symptoms had a 3.0 times higher odds of RH. Insomnia was not associated with uncontrolled BP.

CONCLUSIONS

Experiencing insomnia was associated with increased odds of RH in OSA patients. These results suggest that comorbid insomnia may contribute to inadequate BP control in OSA patients.

Association between arterial stiffness and sleep apnoea in patients with resistant hypertension

Resistant Hypertension (RHT) is associated with a higher risk of Obstructive Sleep Apnoea (OSA). OSA and aortic stiffness (AS) measured by Pulse Wave Velocity (PWV) are independent risk factors for cardiovascular events. We assessed, in a cross-sectional study, the association between AS measured by PWV and OSA severity in patients with RHT. All patients were submitted to polysomnography, PWV measure and 24 h ABPM. Bivariate analysis compared patients with and without moderate/severe OSA. Multivariate analysis was performed to assess the independent correlates of moderate/severe OSA. A total of 376 patients were included, 31% were men with a mean age of 63 ± 10 years. Moderate/severe OSA was diagnosed in 214 patients (57%), 63 patients (17%) presented AS. Uncontrolled ABPM (true RHT) was found in 215 patients (57.2%) and among them 113 were diagnosed with moderate/severe OSA. Evaluating AS in patients with mild, moderate and severe apnoea, we observed a progressive increase in PWV (8.19 ± 1.55, 8.51 ± 1.84, 8.67 ± 1.68, respectively). Classifying them in 2 groups: (1) without apnoea/mild apnoea and (2) moderate/severe apnoea, we found higher values in group 2 (8.21 ± 1.52 m/s vs. 8.60 ± 1.75 m/s, p = 0.02), especially among true RHT patients (8.28 ± 1.62 vs. 8.81 ± 1.86, p = 0.029), women (8.13 ± 1.49 vs. 8.55 ± 1.73, p = 0.036), and uncontrolled nocturnal systolic BP (8.49 ± 1.63 vs. 8.58 ± 1.78, p = 0.04). In conclusion, in this RHT cohort, although with borderline results, the more severe the apnoea, the greater the arterial stiffness, mainly among women, true RHT and patients with an adverse nocturnal BP profile.

Differences in the prevalence of cardiovascular and metabolic diseases coinciding with clinical subtypes of obstructive sleep apnea

BACKGROUND

It is unclear about the cardiovascular and metabolic diseases (CMD) among Chinese patients with different clinical subtypes of obstructive sleep apnea (OSA).

HYPOTHESIS

The prevalence of CMD varies among OSA patients of different clinical subtypes.

METHODS

A total of 1483 Chinese patients with OSA were assessed to evaluate the existence of clinical subtypes of OSA using latent class analysis. We compared the differences in demographic characteristics and prevalence of CMD using ANOVA and χ² tests. Associations between clinical subtypes and disease prevalence were assessed using adjusted logistic regression.

RESULTS

We identified prevalent CMD in Chinese patients with the four subtypes of OSA: excessively sleepy (ES), moderately sleepy with disturbed sleep (ModSwDS), moderately sleepy (ModS), and minimally symptomatic (MinS). The ES subtype had a higher body mass index, average Epworth Sleepiness Scale score, Apnea-hypopnea index, and oxyhemoglobin saturation below 90% compared with the other subtypes (p < .05). The MinS subtype had the lowest mean ESS score (p < .05). We found a significant difference in the prevalence of CMD among the four subtypes, with the highest proportion of cases of CMD in the ES subtype. In adjusted models, significant associations with CMD were also found. ES, ModSwDS, ModS, and MinS subtypes are very high-risk, high-risk, medium-risk, and low-risk in prevalent CMD.

CONCLUSIONS

This study identified four clinical subtypes of OSA in Chinese patients. Each clinical subtype corresponds with a different level of prevalence of CMD; this finding is helpful for the more precise treatment of patients with different clinical manifestations.

Screening for Obstructive Sleep Apnea in Adults: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Obstructive sleep apnea (OSA) is associated with adverse health outcomes.

OBJECTIVE

To review the evidence on screening for OSA in asymptomatic adults or those with unrecognized OSA symptoms to inform the US Preventive Services Task Force.

DATA SOURCES

PubMed/MEDLINE, Cochrane Library, Embase, and trial registries through August 23, 2021; surveillance through September 23, 2022.

STUDY SELECTION

English-language studies of screening test accuracy, randomized clinical trials (RCTs) of screening or treatment of OSA reporting health outcomes or harms, and systematic reviews of treatment reporting changes in blood pressure and apnea-hypopnea index (AHI) scores.

DATA EXTRACTION AND SYNTHESIS

Dual review of abstracts, full-text articles, and study quality. Meta-analysis of intervention trials.

MAIN OUTCOMES AND MEASURES

Test accuracy, excessive daytime sleepiness, sleep-related and general health-related quality of life (QOL), and harms.

RESULTS

Eighty-six studies were included (N = 11 051). No study directly compared screening with no screening. Screening accuracy of the Multivariable Apnea Prediction score followed by unattended home sleep testing for detecting severe OSA syndrome (AHI ≥30 and Epworth Sleepiness Scale [ESS] score &gt;10) measured as the area under the curve in 2 studies (n = 702) was 0.80 (95% CI, 0.78 to 0.82) and 0.83 (95% CI, 0.77 to 0.90). Five studies assessing the accuracy of other screening tools were heterogeneous and results were inconsistent. Compared with inactive control, positive airway pressure was associated with a significant improvement in ESS score from baseline (pooled mean difference, -2.33 [95% CI, -2.75 to -1.90]; 47 trials; n = 7024), sleep-related QOL (standardized mean difference, 0.30 [95% CI, 0.19 to 0.42]; 17 trials; n = 3083), and general health-related QOL measured by the 36-Item Short Form Health Survey (SF-36) mental health component summary score change (pooled mean difference, 2.20 [95% CI, 0.95 to 3.44]; 15 trials; n = 2345) and SF-36 physical health component summary score change (pooled mean difference, 1.53 [95% CI, 0.29 to 2.77]; 13 trials; n = 2031). Use of mandibular advancement devices was also associated with a significantly larger ESS score change compared with controls (pooled mean difference, -1.67 [95% CI, 2.09 to -1.25]; 10 trials; n = 1540). Reporting of other health outcomes was sparse; no included trial found significant benefit associated with treatment on mortality, cardiovascular events, or motor vehicle crashes. In 3 systematic reviews, positive airway pressure was significantly associated with reduced blood pressure; however, the difference was relatively small (2-3 mm Hg).

CONCLUSIONS AND RELEVANCE

The accuracy and clinical utility of OSA screening tools that could be used in primary care settings were uncertain. Positive airway pressure and mandibular advancement devices reduced ESS score. Trials of positive airway pressure found modest improvement in sleep-related and general health-related QOL but have not established whether treatment reduces mortality or improves most other health outcomes.

Genetic determinants of cardiometabolic and pulmonary phenotypes and obstructive sleep apnoea in HCHS/SOL

BACKGROUND

Obstructive Sleep Apnoea (OSA) often co-occurs with cardiometabolic and pulmonary diseases. This study is to apply genetic analysis methods to explain the associations between OSA and related phenotypes.

METHODS

In the Hispanic Community Healthy Study/Study of Latinos, we estimated genetic correlations ρ_g between the respiratory event index (REI) and 54 anthropometric, glycemic, cardiometabolic, and pulmonary phenotypes. We used summary statistics from published genome-wide association studies to construct Polygenic Risk Scores (PRSs) representing the genetic basis of each correlated phenotype (ρ_g>0.2 and p-value<0.05), and of OSA. We studied the association of the PRSs of the correlated phenotypes with both REI and OSA (REI≥5), and the association of OSA PRS with the correlated phenotypes. Causal relationships were tested using Mendelian Randomization (MR) analysis.

FINDINGS

The dataset included 11,155 participants, 31.03% with OSA. 22 phenotypes were genetically correlated with REI. 10 PRSs covering obesity and fat distribution (BMI, WHR, WHRadjBMI), blood pressure (DBP, PP, MAP), glycaemic control (fasting insulin, HbA1c, HOMA-B) and insomnia were associated with REI and/or OSA. OSA PRS was associated with BMI, WHR, DBP and glycaemic traits (fasting insulin, HbA1c, HOMA-B and HOMA-IR). MR analysis identified robust causal effects of BMI and WHR on OSA, and probable causal effects of DBP, PP, and HbA1c on OSA/REI.

INTERPRETATION

There are shared genetic underpinnings of anthropometric, blood pressure, and glycaemic phenotypes with OSA, with evidence for causal relationships between some phenotypes.

FUNDING

Described in Acknowledgments.

Impact of Positive Airway Pressure Therapy Adherence on Outcomes in Patients with Obstructive Sleep Apnea and Chronic Obstructive Pulmonary Disease

Rationale: The co-occurrence of obstructive sleep apnea and chronic obstructive pulmonary disease, termed overlap syndrome, has a poor prognosis. However, data on positive airway pressure (PAP) treatments and their impact on outcomes and costs are lacking. Objectives: This retrospective observational study investigated the effects of PAP on health outcomes, resource usage, and costs in patients with overlap syndrome. Methods: Deidentified adjudicated claims data for patients with overlap syndrome in the United States were linked to objectively measured PAP user data. Patients were considered adherent to PAP therapy if they met Centers for Medicare and Medicaid Services criteria for eight 90-day timeframes from device setup through 2-year follow-up. Propensity score matching was used to create comparable groups of adherent and nonadherent patients. Healthcare resource usage was based on the number of doctor visits, all-cause emergency room visits, all-cause hospitalizations, and PAP equipment and supplies, and proxy costs were obtained. Measurements and Main Results: A total of 6,810 patients were included (mean age, 60.8 yr; 56% female); 2,328 were nonadherent. Compared with the year before therapy, there were significant reductions in the number of emergency room visits, hospitalizations, and severe acute exacerbations during 2 years of PAP therapy in patients who were versus were not adherent (all P < 0.001). This improvement in health status was paralleled by a significant reduction in the associated healthcare costs. Conclusions: PAP usage by patients with overlap syndrome was associated with reduced all-cause hospitalizations and emergency room visits, severe acute exacerbations, and healthcare costs.

Effect of different treatments for obstructive sleep apnoea on blood pressure

OBJECTIVE

Obstructive sleep apnoea (OSA) is a common cause of secondary hypertension. This network meta-analysis (NMA) assessed the effect of different OSA treatments on lowering blood pressure.

METHODS

PubMed, EMBASE, Web of Science, and Cochrane Library databases were searched for relevant randomized controlled trials. The search strategies included the concepts of OSA, blood pressure, hypertension, and blood pressure-reducing treatments without language or data restriction (from inception to 1 June 2021). The outcomes included office SBP, office DBP, daytime SBP (dSBP) and DBP (dDBP), and night-time SBP (nSBP) and DBP (nDBP). A Bayesian network meta-analysis was performed, and mean differences with 95% credibility intervals were calculated.

RESULTS

We reviewed 49 randomized controlled trials involving 4893 patients and the following interventions: continuous positive-airway pressure (CPAP), mandibular advancement devices, nocturnal supplemental oxygen, surgery, β-blocker, angiotensin-converting enzyme inhibitors (ACEIs)/angiotensin receptor blockers (ARBs), renal sympathetic denervation (RDN), mineralocorticoid receptor antagonists (MRAs), calcium channel blockers. MRAs were significantly associated with blood pressure reduction followed by ACEI/ARB. RDN could reduce office SBP, office DBP, 24-h SBP, 24-h DBP, dSBP, and dDBP. CPAP also demonstrated modest blood pressure lowering.

CONCLUSION

MRAs and ACEIs/ARBs can reduce blood pressure effectively in patients with OSA. RDN is a novel hypertension treatment that lowered blood pressure in such patients. CPAP was associated with mild but stable blood pressure reduction, and it might be helpful as an adjunctive therapy in OSA patients with hypertension.

REVIEW REGISTRATION

This systematic review and meta-analysis was registered in PROSPERO: CRD42021240891.