The effect of sleep position on sleep bruxism in adults with obstructive sleep apnea.

BACKGROUND: Most of the respiratory events in adults with obstructive sleep apnea (OSA) occurs in supine position. It has been reported that the contraction of masseter muscles is dependent on the occurrence of arousals rather than on the occurrence of respiratory events. OBJECTIVES: This study had two aims: (1) to compare the rhythmic masticatory muscle activity (RMMA) index in supine position (RMMA_sup) and in non-supine positions (RMMA_nsup) in adults with OSA; and (2) to determine the associations between RMMA index in both supine position and non-supine positions on the one hand, and several demographic and polysomnographic variables on the other hand. METHODS: One hundred OSA participants (36 females and 64 males; mean age = 50.3 years (SD = 10.5)) were selected randomly from among patients with a full-night polysomnographic recording. RMMA_sup index and RMMA_nsup index were compared using Mann-Whitney U-test. Multivariate linear regression analyses were used to predict RMMA index both in supine and non-supine positions based on several demographic and polysomnographic variables. RESULTS: In patients with OSA, the RMMA_sup index was significantly higher than the RMMA_nsup index (p < .001). RMMA_sup index was significantly associated with the arousal index (p = .002) and arousal index in supine position (p < .001). RMMA_nsup index was only significantly associated with the arousal index in non-supine positions (p = .004). CONCLUSION: Within the limitations of this study, RMMAs occur more frequently in supine position than in non-supine positions in patients with OSA. In both sleep positions, RMMAs are associated with arousals.

Prevalence and risk factors of sleep bruxism in adults with primary snoring: a large-scale polysomnographic study.

STUDY OBJECTIVES: To determine the prevalence and risk factors of sleep bruxism (SB) in adults with primary snoring (PS). METHODS: This study included 292 adults with PS (140 males, 152 females; mean age ± SD = 42.8 ±12.2 years; mean BMI ± SD = 26.7 ± 4.7 kg/m2) without previous treatment for snoring. SB was diagnosed based on the frequency of the biomarker of SB: rhythmic masticatory muscle activity (RMMA; SB when RMMA ≥ 2 episodes/hour). Logistic regression was performed, with SB as the dependent variable and with age, sex, BMI, and sleep- and respiratory-related polysomnographic parameters as the independent variables to identify the risk factors for SB. RESULTS: The prevalence of SB was 44.6% in adults with PS. Younger age (OR = 0.965 [0.944, 0.987]) and shorter total sleep time (OR = 0.760 [0.609, 0.948]) significantly increased the risk of SB (P < 0.05). CONCLUSIONS: SB is highly prevalent in adults with PS. Younger age and shorter sleep time are significant risk factors for SB in adults with PS. CLINICAL TRIAL REGISTRATION: Registry: Netherlands Trial Register; Name: A Large Sample Polysomnographic Study on Sleep Bruxism; Identifier: NL8516.

Temporal association between leg movements and respiratory events in patients with obstructive sleep apnea: description and differences between the AASM and WASM scoring criteria.

PURPOSE: To describe the temporal association between leg movements (LMs) and respiratory events in patients with obstructive sleep apnea (OSA), and to quantify the difference in scoring respiratory-related leg movement (RRLM) between the American Academy of Sleep Medicine (AASM) criterion and the criterion recommended by the World Association of Sleep Medicine (WASM). METHODS: Patients with OSA who presented with > 10 LMs of any type per hour of sleep were included in this study. For each participant, RRLMs were scored using both the AASM criterion and the recommended WASM criterion. The occurrence of LMs in relation to respiratory events and the difference in scoring RRLM between the AASM criterion and the criterion recommended by the WASM were quantified. RESULTS: In 32 patients enrolled, mean age was 48.1 ± 11.0 years and 78% were men. LMs were significantly more frequent after respiratory events, followed by before respiratory events, and were rare during respiratory events (P < 0.01). Compared with the AASM criterion, more LMs were classified as RRLMs based on the recommended WASM criterion (P = 0.01). CONCLUSION: LMs are more frequent after respiratory events than before and during respiratory events, and more LMs are scored as RRLMs based on the recommended WASM criterion than based on the AASM criterion.

The Annoying Nature of Snoring Sounds Is Not Only about Intensity: A Pilot Study on Exposed Test Subjects.

This study aims to assess (i) which acoustic characteristics of snoring sounds are associated with the annoying nature of snoring sounds; (ii) whether listeners' heart rates correlate with their perceived annoyance; and (iii) whether perceived annoyance is different between listeners with different experiences with their bedpartners' snoring sounds. Six snoring epochs with distinct acoustic characteristics (viz., reference, high pitch, high intensity, short interval, irregular intensity, and irregular intervals) were collected from snoring patients. Twenty physicians and technicians were involved in the healthcare of snoring patients, and were divided into three groups based on personal experience with their bedpartners' snoring sounds (viz., non-snoring, snoring but not annoying, and snoring and annoying). The test subjects listened to each epoch and rated its level of annoyance. Listeners' heart rates were also recorded during the test using a finger plethysmograph. Within the limitations of this study, it was found that, compared with other snoring sounds, snoring sounds with high intensity and irregularity were associated with higher perceived annoyance. However, higher perceived annoyance of snoring sound was not reflected in heart rate-related parameters. In addition, listeners' personal experiences do not seem to affect their perceived annoyance.

Effects of continuous positive airway pressure and mandibular advancement appliance therapy on sleep bruxism in adults with obstructive sleep apnea: a pilot study.

STUDY OBJECTIVES: This study aimed to investigate the effects of continuous positive airway pressure (CPAP) and mandibular advancement appliance (MAA) therapy on rhythmic masticatory muscle activity (RMMA), a biomarker of sleep bruxism (SB), and to compare the effects of CPAP with MAA in adults with obstructive sleep apnea (OSA). METHODS: This cohort study included individuals with OSA who received treatment with CPAP or MAA. Polysomnographic recordings with and without therapy were performed in each individual. Statistical analyses were performed with repeated measures ANOVA. RESULTS: A total of 38 individuals with OSA were enrolled, 13 on CPAP and 25 with MAA, mean age 52.6 ± 10.6 years, 32 men, mean baseline apnea-hypopnea index (AHI) 26.5 ± 15.2 events/hour, mean RMMA index 3.5 ±events/hour. In the total group, the RMMA index decreased significantly with CPAP and MAA therapies (P < 0.05). The changes in the RMMA index with therapy did not differ significantly between CPAP and MAA (P > 0.05). The RMMA index decreased in 60% of the individuals with OSA, and the changes ranged widely, with a median of 52% and an interquartile range of 107%. CONCLUSIONS: Both CPAP and MAA therapies significantly reduce SB in individuals with OSA. However, the interindividual differences in the effects of these therapies on SB are large. CLINICAL TRIAL REGISTRATION: https://trialsearch.who.int (NL8516); April 08, 2020.

Effects of demographic and sleep-related factors on snoring sound parameters.

OBJECTIVE: To investigate the effect of frequently reported between-individual (viz., age, gender, body mass index [BMI], and apnea-hypopnea index [AHI]) and within-individual (viz., sleep stage and sleep position) snoring sound-related factors on snoring sound parameters in temporal, intensity, and frequency domains. METHODS: This study included 83 adult snorers (mean ± SD age: 42.2 ± 11.3 yrs; male gender: 59%) who underwent an overnight polysomnography (PSG) and simultaneous sound recording, from which a total of 131,745 snoring events were extracted and analyzed. Data on both between-individual and within-individual factors were extracted from the participants' PSG reports. RESULTS: Gender did not have any significant effect on snoring sound parameters. The fundamental frequency (FF; coefficient = -0.31; P = 0.02) and dominant frequency (DF; coefficient = -12.43; P < 0.01) of snoring sounds decreased with the increase of age, and the second formant increased (coefficient = 22.91; P = 0.02) with the increase of BMI. Severe obstructive sleep apnea (OSA; AHI ≥30 events/hour), non-rapid eye movement sleep stage 3 (N3), and supine position were all associated with more, longer, and louder snoring events (P < 0.05). Supine position was associated with higher FF and DF, and lateral decubitus positions were associated with higher formants. CONCLUSIONS: Within the limitations of the current patient profile and included factors, AHI was found to have greater effects on snoring sound parameters than the other between-individual factors. The included within-individual factors were found to have greater effects on snoring sound parameters than the between-individual factors under study.

Associations between snoring and dental sleep conditions: A systematic review.

BACKGROUND: It is important for dentists to know if the presence of snoring is associated with the presence of other dental sleep conditions (e.g. obstructive sleep apnea [OSA], sleep bruxism [SB], gastroesophageal reflux disease [GERD], xerostomia and oro-facial pain). If so, dentists could play a significant role in the early recognition and management of these conditions. OBJECTIVES: This systematic review aimed to: (i) investigate the associations between the presence of snoring and the presence of other dental sleep conditions; and (ii) determine if it is clinically relevant that dentists assess snoring in their population. METHODS: The literature search was performed in PubMed and Embase.com in collaboration with a medical librarian. Studies were eligible if they employed regression models to assess whether snoring was associated with other dental sleep conditions, and/or investigated the incidence of snoring in patients with other dental sleep conditions and vice versa. RESULTS: Of the 5299 retrieved references, 36 eligible studies were included. The available evidence indicates that the presence of snoring is associated with higher probabilities of OSA, GERD and headache. Due to limited evidence and conflicting findings, the currently available articles are not indicative of associations between the presence of snoring and the presence of SB and oral dryness. CONCLUSION: Within the limitations of this study, it can be concluded that the presence of snoring is associated with higher probabilities of OSA, GERD and headache. Therefore, it is clinically relevant that dentists assess snoring in their patient population.

Sleep bruxism is highly prevalent in adults with obstructive sleep apnea: a large-scale polysomnographic study.

STUDY OBJECTIVES: The aim was to determine the prevalence and risk factors of sleep bruxism (SB) and to investigate the relationships between SB episodes, arousals, and respiratory events in adults with obstructive sleep apnea (OSA). METHODS: This prospective study included 914 adults with OSA (305 females, 609 males; age = 53 years [interquartile range = 17]; apnea-hypopnea index = 13.9 events/h [interquartile range = 21]). The diagnosis of SB was made when the rhythmic masticatory muscle activity (RMMA) index was at least 2 episodes/h of sleep based on a full polysomnographic recording. Binary logistic regression was performed to identify risk factors for SB. Network analysis was performed to determine the relations between RMMA, respiratory event, sleep arousal, and other factors. Further, the percentage of RMMA time-related to arousal was calculated. RESULTS: The prevalence of SB in adults with OSA was 49.7%. Male sex, lower body mass index, and higher percentage of N1 sleep increased the odds of having SB (odds ratios = 1.425, 0.951, and 1.032, respectively; all P < .05). Network analysis showed that there were no direct associations between RMMA and apnea-hypopnea index, nor between RMMA and arousal, although 85.7% of RMMA was time-related to arousals. CONCLUSIONS: Nearly half of adults with OSA have comorbid SB. Male sex, lower body mass index, and a higher percentage of light sleep increase the risk of having SB. Although RMMAs do not directly correlate with respiratory events and arousals, most RMMAs are time-related to arousals in adults with OSA. CLINICAL TRIAL REGISTRATION: Registry: Netherlands Trial Register; Name: A Large Sample Polysomnographic Study on Sleep Bruxism; URL: https://trialsearch.who.int/Trial2.aspx?TrialID=NL8516; Identifier: NL8516. CITATION: Li D, Kuang B, Lobbezoo F, de Vries N, Hilgevoord A, Aarab G. Sleep bruxism is highly prevalent in adults with obstructive sleep apnea: a large-scale polysomnographic study. J Clin Sleep Med. 2023;19(3):443-451.

Associated factors of primary snoring and obstructive sleep apnoea in patients with sleep bruxism: A questionnaire study.

BACKGROUND: By being aware of the associated factors of primary snoring (PS) and obstructive sleep apnoea (OSA) in sleep bruxism (SB) patients, dentists may contribute to the screening and early recognition of SB patients with PS or OSA. OBJECTIVE: To identify the associated factors of PS and OSA from questionnaire-based data in SB patients. METHODS: A total of 968 self-reported SB patients (31.6% men; median age 44.5 years) were retrospectively enrolled. Self-reported sleep-related breathing status (viz., no sleep-related breathing condition, PS and OSA) was the dependent variable. Independent variables were questionnaire-based data on demographics, lifestyle, psychological status, pain and sleep. RESULTS: For PS, no statistically significant associated factor was identified in analyses. For OSA, increased age (OR = 1.04 [1.03-1.06]), male gender (OR = 3.33 [2.17-5.00]), daily alcohol consumption (OR = 1.96 [1.18-3.33]), depression (OR = 1.10 [1.06-1.14]), daytime sleepiness (OR = 2.94 [1.85-4.76]) and high risk of gastroesophageal reflux disease (GERD; OR = 2.63 [1.52-4.76]) were found to be significant risk factors, while high risk of temporomandibular disorder (TMD) pain (OR = 0.51 [0.30-0.86]) and chronic pain (OR = 0.73 [0.59-0.90]) were significant protective factors. These results were confirmed in the subsequent network analysis. CONCLUSION: Within the limitations of this study, no associated factor is identified for PS. For OSA, dentists should keep in mind that increased age, male gender, daily alcohol consumption, depression, daytime sleepiness and high GERD risk are associated with increased OSA risk in SB patients, while high TMD-pain risk and chronic pain are associated with decreased OSA risk in this population.

Predicting upper airway collapse sites found in drug-induced sleep endoscopy from clinical data and snoring sounds in patients with obstructive sleep apnea: a prospective clinical study.

STUDY OBJECTIVES: The primary aim was to predict upper airway collapse sites found in drug-induced sleep endoscopy (DISE) from demographic, anthropometric, clinical examination, sleep study, and snoring sound parameters in patients with obstructive sleep apnea (OSA). The secondary aim was to identify the above-mentioned parameters that are associated with complete concentric collapse of the soft palate. METHODS: All patients with OSA who underwent DISE and simultaneous snoring sound recording were enrolled in this study. Demographic, anthropometric, clinical examination (viz., modified Mallampati classification and Friedman tonsil classification), and sleep study parameters were extracted from the polysomnography and DISE reports. Snoring sound parameters during DISE were calculated. RESULTS: One hundred and nineteen patients with OSA (79.8% men; age = 48.1 ± 12.4 years) were included. Increased body mass index was found to be associated with higher probability of oropharyngeal collapse (P < .01; odds ratio = 1.29). Patients with a high Friedman tonsil score were less likely to have tongue base collapse (P < .01; odd ratio = 0.12) and epiglottic collapse (P = .01; odds ratio = 0.20) than those with a low score. A longer duration of snoring events (P = .05; odds ratio = 2.99) was associated with a higher probability of complete concentric collapse of the soft palate. CONCLUSIONS: Within the current patient profile and approach, given that only a limited number of predictors were identified, it does not seem feasible to predict upper airway collapse sites found in DISE from demographic, anthropometric, clinical examination, sleep study, and snoring sound parameters in patients with OSA. CITATION: Huang Z, Bosschieter PFN, Aarab G, et al. Predicting upper airway collapse sites found in drug-induced sleep endoscopy from clinical data and snoring sounds in obstructive sleep apnea patients: a prospective clinical study. J Clin Sleep Med. 2022;18(9):2119-2131.

Associations between sleep bruxism and other sleep-related disorders in adults: a systematic review.

OBJECTIVE: Systematic reviews on sleep bruxism (SB) as a comorbid condition of other sleep-related disorders are lacking. Such reviews would contribute to the insight of sleep clinicians into the occurrence of SB in patients with other sleep-related disorders, and into the underlying mechanisms of such comorbid associations. This systematic review aimed: 1. to determine the prevalence of SB in adults with other sleep-related disorders; and 2. to determine the associations between SB and other sleep-related disorders, and to explain the underlying mechanisms of these associations. METHODS: A systematic search on SB and sleep-related disorders was performed in PubMed, Embase, Cochrane Library, and Web of Science to identify eligible studies published until May 15, 2020. Quality assessment was performed using the Risk of Bias Assessment tool for Non-randomized Studies. RESULTS: Of the 1539 unique retrieved studies, 37 articles were included in this systematic review. The prevalence of SB in adult patients with obstructive sleep apnea, restless leg syndrome, periodic limb movement during sleep, sleep-related gastroesophageal reflux disease, REM behavior disorder (RBD), and sleep-related epilepsy was higher than that in the general population. The specific mechanisms behind these positive associations could not be identified. CONCLUSIONS: SB is more prevalent in patients with the previously mentioned disorders than in the general population. Sleep arousal may be a common factor with which all the identified disorders are associated, except RBD and Parkinson's disease. The associations between SB and these identified sleep-related disorders call for more SB screening in patients with the abovementioned sleep-related disorders.

Prediction of the obstruction sites in the upper airway in sleep-disordered breathing based on snoring sound parameters: a systematic review.

BACKGROUND: Identification of the obstruction site in the upper airway may help in treatment selection for patients with sleep-disordered breathing. Because of limitations of existing techniques, there is a continuous search for more feasible methods. Snoring sound parameters were hypothesized to be potential predictors of the obstruction site. Therefore, this review aims to i) investigate the association between snoring sound parameters and the obstruction sites; and ii) analyze the methodology of reported prediction models of the obstruction sites. METHODS: The literature search was conducted in PubMed, Embase.com, CENTRAL, Web of Science, and Scopus in collaboration with a medical librarian. Studies were eligible if they investigated the associations between snoring sound parameters and the obstruction sites, and/or reported prediction models of the obstruction sites based on snoring sound. RESULTS: Of the 1016 retrieved references, 28 eligible studies were included. It was found that the characteristic frequency components generated from lower-level obstructions of the upper airway were higher than those generated from upper-level obstructions. Prediction models were built mainly based on snoring sound parameters in frequency domain. The reported accuracies ranged from 60.4% to 92.2%. CONCLUSIONS: Available evidence points toward associations between the snoring sound parameters in the frequency domain and the obstruction sites in the upper airway. It is promising to build a prediction model of the obstruction sites based on snoring sound parameters and participant characteristics, but so far snoring sound analysis does not seem to be a viable diagnostic modality for treatment selection.

Perioperative management of obstructive sleep apnea in bariatric surgery: a consensus guideline.

BACKGROUND: The frequency of metabolic and bariatric surgery (MBS) is increasing worldwide, with over 500,000 cases performed every year. Obstructive sleep apnea (OSA) is present in 35%-94% of MBS patients. Nevertheless, consensus regarding the perioperative management of OSA in MBS patients is not established. OBJECTIVES: To provide consensus based guidelines utilizing current literature and, when in the absence of supporting clinical data, expert opinion by organizing a consensus meeting of experts from relevant specialties. SETTING: The meeting was held in Amsterdam, the Netherlands. METHODS: A panel of 15 international experts identified 75 questions covering preoperative screening, treatment, postoperative monitoring, anesthetic care and follow-up. Six researchers reviewed the literature systematically. During this meeting, the "Amsterdam Delphi Method" was utilized including controlled acquisition of feedback, aggregation of responses and iteration. RESULTS: Recommendations or statements were provided for 58 questions. In the judgment of the experts, 17 questions provided no additional useful information and it was agreed to exclude them. With the exception of 3 recommendations (64%, 66%, and 66% respectively), consensus (>70%) was reached for 55 statements and recommendations. Several highlights: polysomnography is the gold standard for diagnosing OSA; continuous positive airway pressure is recommended for all patients with moderate and severe OSA; OSA patients should be continuously monitored with pulse oximetry in the early postoperative period; perioperative usage of sedatives and opioids should be minimized. CONCLUSION: This first international expert meeting provided 58 statements and recommendations for a clinical consensus guideline regarding the perioperative management of OSA patients undergoing MBS.

Normative values of semitendinosus tendon reflex latencies.

OBJECTIVES: The semitendinosus tendon reflex (STR), also known as the medial hamstring reflex, is rarely described in literature and is believed to provide information mainly concerning the fifth lumbar spinal nerve (L5). Latencies can be obtained with clinical neurophysiological tests. Normative data for STR latencies are not available. The aim of this study was to provide normative values of STR latencies. Also we will describe the technique used for performing the tendon reflex measurements in a clinical neurophysiological setting. METHODS: To determine STR latencies, we measured the stimulus (tap with reflex hammer) - response (EMG activity associated with muscle contraction) relation. The stimulus was administered with a manually operated reflex hammer, tipped with electrically conductive rubber, triggering the EMG recording sweep on impact. The EMG response was recorded with surface electrodes placed on the skin overlying the semitendinosus muscle. RESULTS: Forty healthy subjects participated in the study. The group consisted of 18 women and 22 men with a median age of 30 years. The mean subject body height was 181 cm (SD 8.1). Latencies showed a significant correlation with body height (r = 0.70, R2 = 0.48, P < 0.0001). The mean latency of the STR was 24.73 ms (SD 1.96). The rounded upper limit of normal of individual absolute right-left differences was 2 ms. CONCLUSION: We present, as far as we know, the first report on normative values of STR latencies. The STR could be elicited in 100% of our population. The left-right difference seems to be the most promising clinical parameter for diagnostic purposes. SIGNIFICANCE: We think our results can be of practical use for all clinical neurophysiologists/neurologists and may provide the basis for further research on test characteristics of STR latencies in patients with L5 radiculopathy.

The sleep position trainer: a new treatment for positional obstructive sleep apnoea.

BACKGROUND: Positional obstructive sleep apnoea (POSA), defined as a supine apnoea-hypopnoea index (AHI) twice or more as compared to the AHI in the other positions, occurs in 56 % of obstructive sleep apnoea patients. Positional therapy (PT) is one of several available treatment options for these patients. So far, PT has been hampered by compliance problems, mainly because of the usage of bulky masses placed in the back. In this article, we present a novel device for treating POSA patients. METHODS: Patients older than 18 years with mild to moderate POSA slept with the Sleep Position Trainer (SPT), strapped to the chest, for a period of 29 ± 2 nights. SPT measures the body position and vibrates when the patient lies in supine position. RESULTS: Thirty-six patients were included; 31 patients (mean age, 48.1 ± 11.0 years; mean body mass index, 27.0 ± 3.7 kg/m(2)) completed the study protocol. The median percentage of supine sleeping time decreased from 49.9 % [20.4-77.3 %] to 0.0 % [range, 0.0-48.7 %] (p < 0.001). The median AHI decreased from 16.4 [6.6-29.9] to 5.2 [0.5-46.5] (p < 0.001). Fifteen patients developed an overall AHI below five. Sleep efficiency did not change significantly. Epworth Sleepiness Scale decreased significantly. Functional Outcomes of Sleep Questionnaire increased significantly. Compliance was found to be 92.7 % [62.0-100.0 %]. CONCLUSIONS: The Sleep Position Trainer applied for 1 month is a highly successful and well-tolerated treatment for POSA patients, which diminishes subjective sleepiness and improves sleep-related quality of life without negatively affecting sleep efficiency. Further research, especially on long-term effectiveness, is ongoing.

Evaluation of a new simple treatment for positional sleep apnoea patients.

Obstructive sleep apnoea syndrome is a common clinical problem. Positional sleep apnoea syndrome, defined as having a supine apnoea-hypopnoea index of twice or more compared to the apnoea-hypopnoea index in the other positions, occurs in 56% of obstructive sleep apnoea patients. A limited number of studies focus on decreasing the severity of sleep apnoea by influencing sleep position. In these studies an object was strapped to the back (tennis balls, squash balls, special vests), preventing patients from sleeping in the supine position. Frequently, this was not successful due to arousals while turning from one lateral position to the other, thereby disturbing sleep architecture and sleep quality. We developed a new neck-worn device which influences sleep position by offering a vibration when in supine position, without significantly reducing total sleep time. Thirty patients with positional sleep apnoea were included in this study. No side effects were reported. The mean apnoea-hypopnoea index dropped from 27.7 ± 2.4 to 12.8 ± 2.2. Seven patients developed an overall apnoea-hypopnoea index below 5 when using the device in ON modus. We expect that positional therapy with such a device can be applied as a single treatment in many patients with mild to moderate position-dependent obstructive sleep apnoea, while in patients with a more severe obstructive sleep apnoea such a device could be used in combination with other treatment modalities.