Objective snoring time and carotid intima-media thickness in non-apneic female snorers

Upper airway microcirculation remodeling in obstructive sleep apnea is not driven by endothelial activation

Microcirculation contributes significantly to blood flow resistance, with upper airway microcirculation in obstructive sleep apnea (OSA) affected by endothelial activation, perturbed blood flow shear stress, and snoring-induced tissue vibration. The relevance of these mechanisms on microcirculation response and remodeling remains largely unknown but may influence management decisions in OSA. This study analyzed pharyngeal muscle tissue from non-obese, young adult patients with OSA and chronic heavy snoring. We assessed arteriole morphometry and quantified the expression of endothelial activation markers: 8-isoprostane, vascular cell adhesion molecule-1, E-selectin, vascular endothelial growth factor, endothelin-1, and endothelial cell specific molecule-1. Morphometric analysis of 319 arterioles (mean of 8 vessels per patient) revealed thicker walls in severe OSA compared to mild OSA without lumen reduction, indicating outward hypertrophy, and a positive correlation between the apnea-hypopnea index (a measure of OSA severity) and arteriole wall thickness. However, analysis of 1872 arterioles showed no increase in endothelial activation markers with disease severity, either in the arteriole walls or muscle tissue. This suggests that, in young non-obese adults, severe OSA likely leads to adaptive, mechanically driven microcirculation outward hypertrophy, potentially due to perturbed shear stress, with potential implications for OSA management.

Management of primary snoring in adults: A scoping review examining interventions, outcomes and instruments used to assess clinical effects

While various treatment options for primary snoring are available, evidence-based recommendations to determine the optimal intervention remain unestablished. To inform future directions of research to guide clinical decision-making, this scoping review was conducted to map the existing evidence on interventions for primary snoring, the outcomes and instruments used to assess their clinical effects in adults. The feasibility of conducting further systematic reviews and comparing outcomes across these therapies using network meta-analysis was also assessed. Of the 1673 records identified, 38 interventional studies met the inclusion criteria with three-fifths of them being before-after studies. The most common reason for study exclusion was results being reported for patients with primary snoring and obstructive sleep apnoea (OSA) combined. Interventions were surgical (73 %), behavioural and the use of devices/medications. Twenty-six common outcomes were identified and categorised into six domains. Fifty-nine instruments were used to assess the outcomes and based mainly on non-validated questionnaires. Our findings indicated (1) the need for randomised controlled trials with strict discrimination between patients with primary snoring and OSA, (2) further network meta-analyses using some outcomes is feasible, and (3) a core outcome set to inform standardised reporting for future research should be developed.

How to objectively measure snoring: a systematic review

PURPOSE

Snoring is the most common symptom of obstructive sleep apnea. Various objective methods of measuring snoring are available, and even if the measurement is performed the same way, communication is difficult because there are no common reference values between the researcher and clinician with regard to intensity and frequency, among other variables. In other words, no consensus regarding objective measurement has been reached. This study aimed to review the literature related to the objective measurement of snoring, such as measurement devices, definitions, and device locations.

METHODS

A literature search based on the PubMed, Cochrane, and Embase databases was conducted from the date of inception to April 5, 2023. Twenty-nine articles were included in this study. Articles that mentioned only the equipment used for measurement and did not include individual details were excluded from the study.

RESULTS

Three representative methods for measuring snoring emerged. These include (1) a microphone, which measures snoring sound; (2) piezoelectric sensor, which measures snoring vibration; and (3) nasal transducer, which measures airflow. In addition, recent attempts have been made to measure snoring using smartphones and applications.

CONCLUSION

Numerous studies have investigated both obstructive sleep apnea and snoring. However, the objective methods of measuring snoring and snoring-related concepts vary across studies. Consensus in the academic and clinical communities on how to measure and define snoring is required.

Regular snoring is associated with uncontrolled hypertension

Snoring may be a risk factor for cardiovascular disease independent of other co-morbidities. However, most prior studies have relied on subjective, self-report, snoring evaluation. This study assessed snoring prevalence objectively over multiple months using in-home monitoring technology, and its association with hypertension prevalence. In this study, 12,287 participants were monitored nightly for approximately six months using under-the-mattress sensor technology to estimate the average percentage of sleep time spent snoring per night and the estimated apnea-hypopnea index (eAHI). Blood pressure cuff measurements from multiple daytime assessments were averaged to define uncontrolled hypertension based on mean systolic blood pressure≥140 mmHg and/or a mean diastolic blood pressure ≥90 mmHg. Associations between snoring and uncontrolled hypertension were examined using logistic regressions controlled for age, body mass index, sex, and eAHI. Participants were middle-aged (mean ± SD; 50 ± 12 y) and most were male (88%). There were 2467 cases (20%) with uncontrolled hypertension. Approximately 29, 14 and 7% of the study population snored for an average of >10, 20, and 30% per night, respectively. A higher proportion of time spent snoring (75th vs. 5th; 12% vs. 0.04%) was associated with a ~1.9-fold increase (OR [95%CI]; 1.87 [1.63, 2.15]) in uncontrolled hypertension independent of sleep apnea. Multi-night objective snoring assessments and repeat daytime blood pressure recordings in a large global consumer sample, indicate that snoring is common and positively associated with hypertension. These findings highlight the potential clinical utility of simple, objective, and noninvasive methods to detect snoring and its potential adverse health consequences.

Exploring the dynamics of snoring in relation to sleep stages: Implications for gender differences, sleep position, and upper airway collapsibility

OBJECTIVE

The purpose of this study was to determine the sleep stage during which isolated snoring occurs in children and adults, and to analyze changes after treatment of obstructive sleep apnea (OSA).

METHODS

This retrospective study examined duration of snoring time and respiratory events during each sleep stage in adults and children who underwent polysomnography, had an apnea-hypopnea index (AHI) < 15/h and had snoring time ≥ 10% of total sleep time. Changes in duration of snoring time were also examined in adult patients after treatment with an oral appliance (OA).

RESULTS

Snoring time was shown to be predominant during N3 and N2 sleep and less dominant during REM sleep in both children (n = 47) and adults (n = 93). These results were seen even in children with REM dependency. The percentage of snoring time during N3 sleep was more pronounced in women than in men among young adult patients aged < 40 years but was not significantly different between men and women overall. There were no significant differences in the percentage of snoring time in each sleep stage between young women with mild OSA and non-OSA. In children, there were no significant differences between boys and girls in the percentage of snoring time in any sleep stage. The percentage of snoring time during N3 was significantly higher sleep in the non-supine position than in the supine position in children, whereas no significant differences were noted between the supine and non-supine positions in any sleep stage in adults. OA treatment for adult patients (n = 20) significantly increased the percentage of snoring time during N3 sleep, although it significantly decreased AHI, total snoring time, and snoring time during N1 sleep and REM sleep.

CONCLUSIONS

Snoring presented exclusively during the N3 sleep stage, especially in young women with mild OSA, and in children with OSA, especially in the non-supine position. Snoring time during N3 sleep increased during OA treatment for OSA.

Effect of physical activity on the change in carotid intima-media thickness: An 8-year prospective cohort study

BACKGROUND AND AIMS

There is a demand for longitudinal studies that use both objective and subjective measures of physical activity to investigate the association of physical activity with the change in carotid intima-media thickness (CIMT). In order to investigate such association, we conducted an 8-year follow-up study that used both objective and subjective measures of physical activity.

METHODS

This cohort study used subsamples of the ongoing Korean Genome and Epidemiology Study (KoGES). Included participants were between 49 to 79 years of age at baseline. Exclusion criteria included incomplete assessments of pedometer/accelerometer, international physical activity questionnaire (IPAQ), and baseline CIMT. Participants with a history of cardiovascular diseases were further excluded. Linear regression models were used for the main analysis. Age differences were assessed by stratifying the participants into < 60 years and ≥ 60 years.

RESULTS

After removing excluded participants, 835 participants were included in the final analysis (age, 59.84 ± 6.53 years; 326 (39.04%) males). 453 participants were < 60 years and 382 participants were ≥ 60 years. The daily total step count was inversely associated with the percent change in overall CIMT over 8-years (β = -0.015, standard error = 0.007, P = 0.034). This association was present among participants in the < 60-year-old group (β = -0.026, standard error = 0.010, P = 0.006), but not among participants in the ≥ 60-year-old group (β = -0.010, standard error = 0.011, P = 0.38).

CONCLUSIONS

The findings suggest that taking preemptive actions of increasing physical activity may prevent the incidence of atherosclerosis.

Positive correlation between snoring and dyslipidemia in adults: results from NHANES

BACKGROUND

A few studies have shown that snoring, in certain populations, is associated with dyslipidemia. However, there are currently no large-scale national studies available that explore this association. Thus, for further clarification, studies using a large sample of the general population need to be conducted. This study aimed to explore this association using the National Health and Nutrition Examination Survey (NHANES) database.

METHODS

A cross-sectional survey was conducted using data from the NHANES database; 2005 to 2008 and 2015 to 2018 datasets were used (weighted to be representative of United States adults aged ≥ 20 years). Information on snoring status, lipid levels, and confounding factors were included. Logistic regression of the generalized linear model was used to analyze the relationship between snoring and dyslipidemia, and hierarchical analysis, interaction analysis, and sensitivity analysis were used to explore the stability of the results.

RESULTS

Data from 28,687 participants were analyzed, and 67% of the participants had some degree of snoring. The fully adjusted multivariate logistic regression results demonstrated that snoring frequency was significantly positively associated with dyslipidemia (P < 0.001 for linear trend). Adjusted odds ratios (aORs) of dyslipidemia among those who snored rarely, occasionally, and frequently were 1.1 (95% confidence interval [CI], 1.02-1.18), 1.23 (95% CI, 1.10-1.38), and 1.43 (95% CI, 1.29-1.58), respectively, compared with that among those who never snored. In addition, age and snoring frequency showed a correlation (P = 0.02). Sensitivity analysis demonstrated that frequent snoring was significantly associated with lipid levels (all P ≤ 0.01 for linear trend), including increased low-density lipoprotein cholesterol (LDL-C) (β = 0.09 mmol/L; 95% CI, 0.02-0.16), triglyceride (TG) (β = 0.18 mmol/L; 95% CI, 0.10-0.26), total cholesterol (TC) (β = 0.11 mmol/L; 95% CI, 0.05-0.16), and decreased high-density lipoprotein cholesterol (HDL-C) (β=-0.04 mmol/L; 95% CI, -0.06--0.03).

CONCLUSIONS

A statistically significant positive association was identified between sleep snoring and dyslipidemia. It was suggested that sleep snoring interventions may reduce the risk of dyslipidemia.

Australasian Sleep Association position statement on consensus and evidence based treatment for primary snoring

Primary snoring impacts a significant portion of the adult population and has the potential to significantly impair quality of life. The purpose of these guidelines is to provide evidence-based recommendations to assist Australasian practitioners in the management of adult patients who present with primary snoring without significant obstructive sleep apnoea. The Timetable, Methodology and Standards by which this Position Statement has been established is outlined in the Appendix S1. The main recommendations are: Weight loss, and reduced alcohol consumption should be recommended, where appropriate If clinical judgement dictates, benzodiazepine and opioid reduction or avoidance may be advised Positional therapy should be considered in supine dominant snorers In dentate patients, Mandibular advancement devices (MAD) should be recommended as a first line treatment following assessment by both an appropriate Dentist and Sleep physician Continuous positive airway pressure (CPAP) devices may be recommended in patients with primary snoring in those already committed to their use or willing to try Surgical treatment of primary snoring by an appropriately credentialled surgeon may be advised and includes nasal (adjunctive), palatal and other interventions This position statement has been designed based on the best available current evidence and our combined expert clinical experience to facilitate the management of patients who present with primary snoring. It provides clinicians with a series of both non-surgical and surgical options with the aim of achieving optimal symptom control and patient outcomes. This is the first such set of recommendations to be established within Australasia and has also been reviewed and endorsed by the Australasian Sleep Association.

ERS technical standards for using type III devices (limited channel studies) in the diagnosis of sleep disordered breathing in adults and children

For more than three decades, type III devices have been used in the diagnosis of sleep disordered breathing in supervised as well as unsupervised settings. They have satisfactory positive and negative predictive values for detecting obstructive and central sleep apnoea in populations with moderately high pre-test probability of symptoms associated with these events. However, standardisation of commercially available type III devices has never been undertaken and the technical specifications can vary widely. None have been subjected to the same rigorous processes as most other diagnostic modalities in the medical field. Although type III devices do not include acquisition of electroencephalographic signals overnight, the minimum number of physical sensors required to allow for respiratory event scoring using standards outlined by the American Academy of Sleep Medicine remains debatable. This technical standard summarises data on type III studies published since 2007 from multiple perspectives in both adult and paediatric sleep practice. Most importantly, it aims to provide a framework for considering current type III device limitations in the diagnosis of sleep disordered breathing while raising research- and practice-related questions aimed at improving our use of these devices in the present and future.

Sleep disordered breathing as a cause and consequence of stroke: A review of pathophysiological and clinical relationships

Stroke is the leading cause of death and disability globally. Sleep disordered breathing (SDB), a potentially modifiable risk factor of stroke, is highly prevalent in stroke survivors. Evidence supports a causal, bidirectional relationship between SDB and stroke. SDB may increase the risk of stroke occurrence and recurrence, and worsen stroke outcome. While SDB is associated with an increased incidence of hypertension and cardiac arrhythmias, both of which are traditional stroke risk factors, SDB is also an independent risk factor for stroke. A number of characteristics of SDB may increase stroke risk, including intermittent hypoxemia, sympathetic activation, changes in cerebral autoregulation, oxidative stress, systemic inflammation, hypercoagulability, and endothelial dysfunction. On the other hand, stroke may also cause new SDB or aggravate preexisting SDB. Continuous positive airway pressure treatment of SDB may have a beneficial role in reducing stroke risk and improving neurological outcome after stroke. The treatment should be considered as early as possible, particularly when SDB is present post-stroke. The goal of this review is to highlight the strong link between SDB and stroke and to raise awareness for practitioners to consider the possibility of SDB being present in all stroke survivors.

Snoring severity is associated with carotid vascular remodeling in young adults with overweight and obesity

BACKGROUND

Snoring is often used as a surrogate measure for obstructive sleep apnea (OSA), a sleep disorder associated with cardiovascular disease (CVD) risk. Whether snoring is linked to CVD independent of OSA remains unclear. We aimed to explore the snoring and subclinical CVD association in adults with and without OSA.

METHODS

We conducted a cross-sectional study in 122 overweight/obese participants (24% male; mean age 40.1 years) attending the 24-month follow-up visit of a lifestyle intervention. Using home-based objective measures of sleep-disordered breathing, we stratified participants into 3 snoring/OSA categories using the snoring index (SI), a measure of snoring vibration, and oxygen desaturation index (ODI): (1) OSA (ODI ≥ 5), (2) non-OSA heavy snorer (ODI <5, above-median SI), and (3) non-OSA low snorer (ODI <5, below-median SI). Vascular measures including pulse wave velocity ([PWV]; carotid-femoral [cf], femoral-ankle [fa], brachial-ankle [ba]), carotid intima-media thickness (IMT), and carotid interadventitial diameter (IAD) were compared across snoring/OSA categories. Linear regressions assessed the association between snoring and subclinical CVD independent of traditional CVD risk factors.

RESULTS

Compared to non-OSA low snorers, common carotid IMT and IAD were higher in non-OSA heavy snorers, and faPWV, IMT, and IAD were higher among those with OSA. The difference between non-OSA heavy snorers and low snorers persisted after adjusting for age, race, sex, blood pressure, body mass index, lipids, and insulin resistance (P < .05 for IMT and IAD).

CONCLUSIONS

In overweight/obese young to middle-aged adults, objectively measured snoring was related to vascular remodeling in those without OSA. Snoring may contribute to CVD risk but warrants further examination in larger prospective cohorts.

Obstructive sleep apnoea and cardiovascular disease: a literature review

As obesity becomes more common worldwide, the prevalence of obstructive sleep apnoea (OSA) continues to rise. Obstructive sleep apnoea is a well-known disorder that causes chronic intermittent hypoxia (CIH), which is considered a risk factor for atherosclerosis directly and indirectly. Ischaemic heart disease remains the leading cause of death. Most risk factors for atherosclerosis are well understood. However, other factors such as CIH are less well understood. Several studies have investigated the pathophysiology of CIH, attempting to uncover its link to atherosclerosis and to determine whether OSA treatment can be a therapeutic modality to modify the risk for atherosclerosis. In this article, we will review the pathophysiology of OSA as an independent risk factor for cardiovascular disease and discuss the most common markers that have been studied. We will also examine the potential impact of OSA management as a risk factor modifier on the reversibility of atherosclerosis.

The Relationship between Simple Snoring and Metabolic Syndrome: A Cross-Sectional Study

PURPOSE

This cross-sectional study was performed to assess the relationship between simple snoring and metabolic syndrome (MetS).

METHODS

A total of 5635 participants including 300 healthy volunteers without snoring allegedly were initially included from 2007 to 2016. Polysomnographic variables, anthropometric measurements, and biochemical indicators were collected. The polynomial linear trend test was used to assess the linear trend across snoring intensity for metabolic score, and logistic regression was used to evaluate the odds ratios (ORs) for MetS after controlling for age, sex, obesity, smoking status, and alcohol consumption.

RESULTS

The final study population consisted of 866 participants. Simple snorers showed more severe metabolic disorders and higher prevalence of MetS than nonsnorers. A significant linear trend was observed between snoring intensity and metabolic score. Simple snoring was significantly associated with increased odds for MetS among all participants (OR = 2.328, 95% CI: 1.340-4.045) and female participants (OR = 2.382, 95% CI: 1.136-4.994) after multivariable adjustment. With regard to MetS components, simple snoring was significantly associated with increased odds for hypertension (OR = 1.730, 95% CI: 1.130-2.650), abdominal obesity (OR = 1.810, 95% CI: 1.063-3.083), and hyper-triglycerides (TG) (OR = 1.814, 95% CI: 1.097-2.998) among all participants, with hypertension (OR = 3.493, 95% CI: 1.748-6.979) among males and with abdominal obesity (OR = 2.306, 95% CI: 1.245-4.270) and hyper-TG (OR = 2.803, 95% CI: 1.146-6.856) among females after multivariable adjustment.

CONCLUSIONS

After excluding the influence of repeated apnea and hypoxia, simple snoring was still significantly associated with MetS, especially in women. Furthermore, the associations were more obvious for hypertension among males and for abdominal obesity and hyper-TG among females. In addition to OSA, simple snoring also should be valued.

Sleep and Migraine: Assessment and Treatment of Comorbid Sleep Disorders

The relationship of sleep and migraine is unequivocal and familiarity with the nature and magnitude of these associations may inform clinical practice. Recent prospective, longitudinal, and time-series analysis has begun to unravel the magnitude and temporal patterns of sleep and migraine. Prospective evidence has shown that sleep variables can trigger acute migraine, precede and predict new onset headache by several years, and indeed, sleep disturbance and snoring are risk factors for chronification. The presence of a sleep disorder is associated with more frequent and severe migraine and portends a poorer headache prognosis. Interestingly, the disorders linked to migraine are quite varied, including insomnia, snoring and obstructive sleep apnea, restless legs, circadian rhythm disorders, narcolepsy, and others. Insomnia is by far the most common sleep disorder in headache patients. In fact, the majority of patients with chronic migraine presenting for treatment have insomnia. Despite a rapidly expanding literature, very few controlled treatment studies have been published to guide clinical practice. This paper focuses on clinical assessment and treatment of sleep disorders. An algorithm is presented for sleep disorders management in the migraine patient, which highlights major sleep disorders and psychiatric comorbidity. Diagnostic procedures are recommended that are conducive to clinical practice. Suggested tools include the sleep history, screening mnemonics, prediction equation, and sleep diary. New developments in treatment have produced abbreviated and cost-effective therapies for insomnia and obstructive sleep apnea that may reach a larger population. Revisions in the diagnostic manuals for sleep and headache disorders enhance recognition of sleep-related headache. Recommendations include behavioral sleep regulation, shown in recent controlled trials to decrease migraine frequency, management for sleep apnea headache, cognitive behavioral therapy (CBT) for insomnia abbreviated for the physician practice setting, sleep-related headache trigger, and others. There is no empirical evidence that sleep evaluation should delay or supersede usual headache care. Rather, sleep management is complimentary to standard headache practice.