Sleep-promoting neurons remodel their response properties to calibrate sleep drive with environmental demands.

Falling asleep at the wrong time can place an individual at risk of immediate physical harm. However, not sleeping degrades cognition and adaptive behavior. To understand how animals match sleep need with environmental demands, we used live-brain imaging to examine the physiological response properties of the dorsal fan-shaped body (dFB) following interventions that modify sleep (sleep deprivation, starvation, time-restricted feeding, memory consolidation) in Drosophila. We report that dFB neurons change their physiological response-properties to dopamine (DA) and allatostatin-A (AstA) in response to different types of waking. That is, dFB neurons are not simply passive components of a hard-wired circuit. Rather, the dFB neurons intrinsically regulate their response to the activity from upstream circuits. Finally, we show that the dFB appears to contain a memory trace of prior exposure to metabolic challenges induced by starvation or time-restricted feeding. Together, these data highlight that the sleep homeostat is plastic and suggests an underlying mechanism.

Management of Persistent, Post-adenotonsillectomy Obstructive Sleep Apnea in Children: An Official American Thoracic Society Clinical Practice Guideline.

Background: Obstructive sleep apnea (OSA) is the most common sleep-related breathing disorder. Although adenotonsillectomy is first-line management for pediatric OSA, up to 40% of children may have persistent OSA. This document provides an evidence-based clinical practice guideline on the management of children with persistent OSA. The target audience is clinicians, including physicians, dentists, and allied health professionals, caring for children with OSA. Methods: A multidisciplinary international panel of experts was convened to determine key unanswered questions regarding the management of persistent pediatric OSA. We conducted a systematic review of the relevant literature. The Grading of Recommendations, Assessment, Development, and Evaluation approach was used to rate the quality of evidence and the strength of the clinical recommendations. The panel members considered the strength of each recommendation and evaluated the benefits and risks of applying the intervention. In formulating the recommendations, the panel considered patient and caregiver values, the cost of care, and feasibility. Results: Recommendations were developed for six management options for persistent OSA. Conclusions: The panel developed recommendations for the management of persistent pediatric OSA based on limited evidence and expert opinion. Important areas for future research were identified for each recommendation.

A novel TASK channel antagonist nasal spray reduces sleep apnea severity in physiological responders: a randomized, blinded, trial.

Preclinical and human physiological studies indicate that topical, selective TASK 1/3 K+ channel antagonism increases upper airway dilator muscle activity and reduces pharyngeal collapsibility during anesthesia and nasal breathing during sleep. The primary aim of this study was to determine the effects of BAY2586116 nasal spray on obstructive sleep apnea (OSA) severity and whether individual responses vary according to differences in physiological responses and route of breathing. Ten people (5 females) with OSA [apnea-hypopnea index (AHI) = 47 ± 26 events/h (means ± SD)] who completed previous sleep physiology studies with BAY2586116 were invited to return for three polysomnography studies to quantify OSA severity. In random order, participants received either placebo nasal spray (saline), BAY2586116 nasal spray (160 µg), or BAY2586116 nasal spray (160 µg) restricted to nasal breathing (chinstrap or mouth tape). Physiological responders were defined a priori as those who had improved upper airway collapsibility (critical closing pressure ≥2 cmH2O) with BAY2586116 nasal spray (NCT04236440). There was no systematic change in apnea-hypopnea index (AHI3) from placebo versus BAY2586116 with either unrestricted or nasal-only breathing versus placebo (47 ± 26 vs. 43 ± 27 vs. 53 ± 33 events/h, P = 0.15). However, BAY2586116 (unrestricted breathing) reduced OSA severity in physiological responders compared with placebo (e.g., AHI3 = 28 ± 11 vs. 36 ± 12 events/h, P = 0.03 and ODI3 = 18 ± 10 vs. 28 ± 12 events/h, P = 0.02). Morning blood pressure was also lower in physiological responders after BAY2586116 versus placebo (e.g., systolic blood pressure = 137 ± 24 vs. 147 ± 21 mmHg, P < 0.01). In conclusion, BAY2586116 reduces OSA severity during sleep in people who demonstrate physiological improvement in upper airway collapsibility. These findings highlight the therapeutic potential of this novel pharmacotherapy target in selected individuals.NEW & NOTEWORTHY Preclinical findings in pigs and humans indicate that blocking potassium channels in the upper airway with topical nasal application increases pharyngeal dilator muscle activity and reduces upper airway collapsibility. In this study, BAY2586116 nasal spray (potassium channel blocker) reduced sleep apnea severity in those who had physiological improvement in upper airway collapsibility. BAY2586116 lowered the next morning's blood pressure. These findings highlight the potential for this novel therapeutic approach to improve sleep apnea in certain people.

Polysomnographic airflow shapes and site of collapse during drug-induced sleep endoscopy.

BACKGROUND: Differences in the pharyngeal site of collapse influence efficacy of non-continuous positive airway pressure therapies for obstructive sleep apnoea (OSA). Notably, complete concentric collapse at the level of the palate (CCCp) during drug-induced sleep endoscopy (DISE) is associated with reduced efficacy of hypoglossal nerve stimulation, but CCCp is currently not recognisable using polysomnography. Here we develop a means to estimate DISE-based site of collapse using overnight polysomnography. METHODS: 182 OSA patients provided DISE and polysomnography data. Six polysomnographic flow shape characteristics (mean during hypopnoeas) were identified as candidate predictors of CCCp (primary outcome variable, n=44/182), including inspiratory skewness and inspiratory scoopiness. Multivariable logistic regression combined the six characteristics to predict clear presence (n=22) versus absence (n=128) of CCCp (partial collapse and concurrent tongue base collapse excluded). Odds ratios for actual CCCp between predicted subgroups were quantified after cross-validation. Secondary analyses examined complete lateral wall, tongue base or epiglottis collapse. External validation was performed on a separate dataset (ntotal=466). RESULTS: CCCp was characterised by greater scoopiness (ß=1.5±0.6 per 2sd, multivariable estimate±se) and skewness (ß=11.4±2.4) compared with non-CCCp. The odds ratio for CCCp in predicted positive versus negative subgroups was 5.0 (95% CI 1.9-13.1). The same characteristics provided significant cross-validated prediction of lateral wall (OR 6.3, 95% CI 2.4-16.5), tongue base (OR 3.2, 95% CI 1.4-7.3) and epiglottis (OR 4.4, 95% CI 1.5-12.4) collapse. CCCp and lateral wall collapse shared similar characteristics (skewed, scoopy), diametrically opposed to tongue base and epiglottis collapse characteristics. External validation confirmed model prediction. CONCLUSIONS: The current study provides a means to recognise patients with likely CCCp or other DISE-based site of collapse categories using routine polysomnography. Since site of collapse influences therapeutic responses, polysomnographic airflow shape analysis could facilitate precision site-specific OSA interventions.

Sleep-related rhythmic movement disorder in adults - A systematic review with a case report.

Sleep-related rhythmic movement disorder is characterised by stereotyped and repetitive rhythmic movements involving large muscle groups during sleep with frequencies between 0.5 and 2 Hz. Most of the published studies on sleep-related rhythmic movement disorder have focussed on children. Therefore, we performed a systematic review on this topic focussing on the adult population. The review is followed by a case report. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. A total of seven manuscripts (n = 32 individuals) were included in the review. The clinical manifestation of body or head rolling predominated in the majority of included cases (53.13% and 43.75%, respectively). In n = 11 (34.37%) cases, a combination of rhythmic movements was observed. The literature review also revealed a wide spectrum of co-morbidities: insomnia, restless leg syndrome, obstructive sleep apnea, ischaemic stroke, epilepsy, hypertension, alcohol and drug dependency, mild depression, and diabetes mellitus. The case report presented a 33-year-old female who was referred to the sleep laboratory due to a suspicion of sleep bruxism and obstructive sleep apnea. Although the patient was initially suspected of having obstructive sleep apnea and sleep bruxism, after conducting video-polysomnography she met the criteria for sleep-related rhythmic movement disorder as she presented body rolling, which were surprisingly most evident during the rapid eye movement sleep stage. In summary, the prevalence of sleep-related rhythmic movement disorder among adults has not been determined yet. The present review and case report is a good starting point for discussion regarding rhythmic movement disorder in adults and further research on this topic.

Network analysis of sleep bruxism in the EPISONO adult general population.

Sleep bruxism (SB) has been associated with biological and psychosocial factors. The assessment of SB includes self-report, clinical evaluation, and polysomnography. This study aimed to investigate the associations of self-reported SB with other sleep disorders and demographic, psychological, and lifestyle factors in the adult general population, and to investigate whether self-reported SB and polysomnographically (PSG) confirmed SB provide similar outcomes in terms of their associated factors. We recruited 915 adults from the general population in Sao Paulo, Brazil. All participants underwent a one-night PSG recording and answered questions about sex, age, BMI, insomnia, OSA risk, anxiety, depression, average caffeine consumption, smoking frequency, and alcohol consumption frequency. We investigated the link between SB and the other variables in univariate, multivariate, and network models, and we repeated each model once with self-reported SB and once with PSG-confirmed SB. Self-reported SB was only significantly associated with sex (p = 0.042), anxiety (p = 0.002), and depression (p = 0.03) in the univariate analysis, and was associated with insomnia in the univariate (p < 0.001) and multivariate (ß = 1.054, 95%CI 1.018-1.092, p = 0.003) analyses. Network analysis showed that self-reported SB had a direct positive edge to insomnia, while PSG-confirmed SB was not significantly associated with any of the other variables. Thus, sleep bruxism was positively associated with insomnia only when self-reported, while PSG-confirmed SB was not associated with any of the included factors.

An independent comparison of the Novolytix salivary melatonin radioimmunoassay with the new Novolytix salivary melatonin enzyme-linked immunosorbent assay.

The dim light melatonin onset (DLMO) is the current gold standard biomarker of the timing of the central circadian clock in humans and is often assessed from saliva samples. To date, only one commercially available salivary melatonin assay is considered accurate at the low daytime levels required to accurately detect the DLMO (Novolytix RIA RK-DSM2). The aim of this study was to conduct the first independent evaluation of a newly improved enzyme-linked immunosorbent assay (ELISA; Novolytix MLTN-96) and compare it with the recommended radioimmunoassay (RIA)-both in terms of melatonin concentrations and derived DLMOs. Twenty participants (15 females, 18-59 years old) provided saliva samples every 30 min in dim light starting 6 h before their habitual bedtime, yielding a total of 260 saliva samples. Both the RIA and ELISA yielded daytime melatonin concentrations <2 pg/mL, indicating adequate accuracy to detect the DLMO. The melatonin concentrations from the two assays were highly correlated (r = .94, p < .001), although the RIA yielded lower levels of melatonin concentration than the ELISA, on average by 0.70 pg/mL (p = .006). Seventeen DLMOs were calculated from the melatonin profiles and the DLMOs from both assays were not statistically different (p = .36) and were highly correlated (r = .97, p < .001). Two DLMOs derived from the RIA occurred more than 30 min earlier than the DLMO derived from the ELISA. These results indicate that the new Novolytix ELISA is an appropriate assay to use if the Novolytix RIA is not feasible or available.

Influence of occlusal appliances on the masticatory muscle function in individuals with sleep bruxism: A systematic review and meta-analysis.

This systematic review answers the question: "Does occlusal appliance use influence masticatory muscle function of dentate individuals with sleep bruxism?". The literature search included six databases, grey literature, and manual search for articles. Randomized and non-randomized clinical trials were included comparing muscle function of sleep bruxers before and after receiving occlusal appliances. Risk of bias was assessed with risk of bias assessment for randomized and non-randomized clinical trials tool. Twelve studies, three represent randomized clinical trials, were included. Risk of bias was considered low, moderate, or serious. Meta-analyses indicated that soft and hard appliances did not influence muscle activity and bite force of bruxers. Qualitative analysis showed that occlusal appliance use did not influence masticatory performance and muscle volume. However, it was effective in reducing tongue force. Certainty of evidence was considered very low for muscle activity when evaluated with hard appliances, and for bite force evaluated with both appliance materials. Low certainty of evidence was observed for muscle activity with soft appliances. Based on the findings of this meta-analysis, occlusal appliances do not affect masticatory muscle function of sleep bruxers. Regardless of appliance material, the activity of masseter and temporal, and bite force of sleep bruxers was not influenced.

The Combination of Aroxybutynin and Atomoxetine in the Treatment of Obstructive Sleep Apnea (MARIPOSA): A Randomized Controlled Trial.

Rationale: Obstructive sleep apnea (OSA) is a common sleep disorder for which the principal treatment option, continuous positive airway pressure, is often poorly tolerated. There is currently no approved pharmacotherapy for OSA. However, recent studies have demonstrated improvement in OSA with combined antimuscarinic and noradrenergic drugs. Objectives: The aim of this study was to evaluate the efficacy and safety of AD109, a combination of the novel antimuscarinic agent aroxybutynin and the norepinephrine reuptake inhibitor atomoxetine, in the treatment of OSA. Methods: Phase II randomized, double-blind, placebo-controlled, parallel-group, 4-week trial comparing AD109 2.5/75 mg, AD109 5/75 mg, atomoxetine 75 mg alone, and placebo (www.clinicaltrials.gov identifier NCT05071612). Measurements and Main Results: Of 211 randomized patients, 181 were included in the prespecified efficacy analyses. Sleep was assessed by two baseline and two treatment polysomnograms. Apnea-hypopnea index with a 4% desaturation criterion (primary outcome) was reduced from a median (IQR) of 20.5 (12.3-27.2) to 10.8 (5.6-18.5) in the AD109 2.5/75 mg arm (-47.1%), from 19.4 (13.7-26.4) to 9.5 (6.1-19.3) in the AD109 5/75 mg arm (-42.9%; both P < 0.0001 vs. placebo), and from 19.0 (11.8-28.8) to 11.8 (5.5-21.5) with atomoxetine alone (-38.8%; P < 0.01 vs. placebo). Apnea-hypopnea index with a 4% desaturation criterion decreased from 20.1 (11.9-25.9) to 16.3 (11.1-28.9) in the placebo arm. Subjectively, there was improvement in fatigue with AD109 2.5/75 mg (P < 0.05 vs. placebo and atomoxetine). Atomoxetine taken alone decreased total sleep time (P < 0.05 vs. AD109 and placebo). The most common adverse events were dry mouth, insomnia, and urinary hesitancy. Conclusions: AD109 showed clinically meaningful improvement in OSA, suggesting that further development of the compound is warranted. Clinical trial registered with www.clinicaltrials.gov (NCT05071612).

Does oral appliance efficacy in treating obstructive sleep apnea depend on the appliance specialist's experience?

PURPOSE: In France, oral appliances (OAs) are the first-line treatment for moderate and second-line treatment for severe obstructive sleep apnea-hypopnea syndrome. In general, the sleep specialist refers his/her patient to the appliance specialist for the impressions and the fitting. However, is there a relationship between the volume of activity of the appliance specialist and the efficacy of this device? METHODS: Our unit includes seven appliance otolaryngology specialists whose activities are highly variable (number of patients varying by a factor of almost 10). Data from a prospective follow-up registry of patients treated with an OA for moderate and severe obstructive sleep apnea-hypopnea syndrome were studied, and differences in outcomes between practitioners in the team were sought. RESULTS: Among 859 patients, OAs significantly reduced the apnea-hypopnea index. Even if the patients were not completely comparable from one practitioner to another, there was a significant heterogeneity in efficacy (complete or partial response of the apnea-hypopnea index and failure of OAs) between practitioners (p = 0.0038; 0.0011; 0.0007 respectively), with better results in practitioners with a higher level of OA activity. CONCLUSION: The findings suggest that it may be preferable to refer patients to OA practitioners who see a higher volume of patients with moderate or severe obstructive sleep apnea-hypopnea syndrome treated with an OA.

Association of Sleep Duration with Tooth Loss and Periodontitis: Insights from the National Health and Nutrition Examination Surveys (2005-2020).

OBJECTIVE: Sleep disorders such as insomnia, apnea, and restless leg syndrome can negatively affect a person's overall health and may cause hypertension, heart failure, and coronary heart disease. Likewise, periodontitis, a gum disease, can lead to both physical and psychological health issues, exerting a considerable effect on one's overall well-being-periodontitis stands as a primary cause of tooth loss. Nevertheless, there has been insufficient research on the correlation between the amount of sleep individuals get and the occurrence of periodontitis/tooth loss among Americans. Therefore, this study aimed to assess the influence of sleep length on periodontitis in the American population. METHODS: Periodontitis severity was classified (none, mild, moderate, and severe) using American Periodontal Association criteria. Sleep duration was assessed by self-reported data and categorized into three groups (deficient, adequate, and excessive). Tooth loss was assessed by the oral examination. To establish a connection between the duration of sleep and periodontitis/tooth loss, a weighted multivariable logistic regression analysis was employed. A GAM analysis and smooth curve fitting assessment were conducted to identify non-linear relationships. Subgroup, interaction, and mediation analyses were also performed. RESULTS: The prevalence of tooth loss was significantly high, affecting 96.4% of the individuals, whereas 46.6% of the study sample experienced moderate to severe periodontitis. The average age of participants was 52.7 years. After adjusting for potential confounding factors, the analysis of weighted multivariable logistic regression revealed a significant association between sleep insufficiency and moderate/severe periodontitis (OR 1.15, 95% CI 1.01-1.30, P = 0.0298), as well as tooth loss (OR 1.16, 95% CI 1.01-1.33, P = 0.0371). Additionally, the research showed a correlation between the length of sleep and periodontitis that followed a U-shaped pattern. In addition, the analysis of mediation revealed that high blood pressure explained 7.0% (95% CI 4.0% to 12.9%; P < 0.0001) of the link between the amount of sleep and the likelihood of losing teeth. CONCLUSION: Sleep duration was independently correlated with moderate/severe periodontitis/tooth loss and had a non-linear relationship.

Assessing the immediate impact of Twin-block appliance insertion on adolescents' sleep using a wearable device.

OBJECTIVE: This prospective clinical study aimed to evaluate the immediate impact of Twin-block appliance insertion on the sleep of adolescents using a wearable device. MATERIALS AND METHODS: A total of 24 girls, aged 11-13 years, with Class II division 1 molar relationship, skeletal class 2 malocclusion (ANB ≥5) and overjet measuring ≥5 mm were selected. Exclusion criteria included a history of previous orthodontic treatment, systemic disease, irregular sleep pattern, obstructive sleep apnea, medical history of breathing disorders, or concurrent use of medications. Participants wore a wearable device to measure sleep parameters, including deep sleep, light sleep, minutes awake during sleep, wake-up times, bedtimes and total sleep times. The participants wore the device for 10 days prior to Twin-block insertion and sleep data were collected for another 10 days after insertion. RESULTS: Following the insertion of the Twin-block appliance, there was a highly statistically significant shift in bedtime and wake-up time to later hours (P < .001). All participants experienced a highly significant delay in bedtime compared to the recommended 10 pm time (P < .001). Additionally, there was a significant increase in the duration of light sleep (P < .05). However, the effect on deep sleep, minutes awake during sleep and sleep duration was not statistically significant. None of the sleep parameters tested showed statistically significant changes between the first 5 days after Twin-block insertion with the subsequent 5 days. CONCLUSION: The immediate insertion of the Twin-block appliance disrupts sleep onset, wake-up time and light sleep during the specified period of 10 days.

Predictors of surgical outcomes for limited palatal muscle resection in patients with obstructive sleep apnea.

OBJECTIVE: Limited palatal muscle resection (LPMR) is a modified palatal surgical technique to correct retropalatal obstruction without complications. This study aims to determine the associated factors affecting the success and cure rate of LPMR in patients with obstructive sleep apnea (OSA), thus guiding patient selection and improving surgical outcome. METHODS: Thirty-five OSA patients underwent LPMR were enrolled. All patients received routine physical examination, preoperative drug-induced sleep endoscopy (DISE), and polysomnography (PSG). Clinical, polysomnographic, cephalometric variables, and DISE findings were evaluated. These measurements were compared between the surgical success and failure group based on the results of preoperative and postoperative PSG. Furthermore, we compared the cured and non-cured groups in the surgical success group. RESULTS: Among 35 patients, the overall success rate was 57 % with a cure rate of 31.4 %. Patients with Friedman stage II had a significantly higher success rate (p = 0.032). According to DISE results, tongue base obstruction affected the surgical outcome (p < 0.001). The success rate was 100 % in the no tongue base obstruction during DISE, 72.2 % in the partial obstruction, and 9.1 % in the total obstruction. Tonsil size is also helpful in predicting surgical success rate (p = 0.041). Furthermore, patients with mild AHI were more likely to be surgical cures. when compared with patients with severe AHI (p = 0.044). CONCLUSION: Patients with larger tonsil size and no tongue base obstruction during DISE may have a higher chance of surgical success with LPMR. The lower AHI may be predictors of surgical cure after LPMR.

Improving physical movement during stroke rehabilitation: investigating associations between sleep measured by wearable actigraphy technology, fatigue, and key biomarkers.

BACKGROUND: Sleep disturbance and fatigue are common in individuals undergoing inpatient rehabilitation following stroke. Understanding the relationships between sleep, fatigue, motor performance, and key biomarkers of inflammation and neuroplasticity could provide valuable insight into stroke recovery, possibly leading to personalized rehabilitation strategies. This study aimed to investigate the influence of sleep quality on motor function following stroke utilizing wearable technology to obtain objective sleep measurements. Additionally, we aimed to determine if there were relationships between sleep, fatigue, and motor function. Lastly, the study aimed to determine if salivary biomarkers of stress, inflammation, and neuroplasticity were associated with motor function or fatigue post-stroke. METHODS: Eighteen individuals who experienced a stroke and were undergoing inpatient rehabilitation participated in a cross-sectional observational study. Following consent, participants completed questionnaires to assess sleep patterns, fatigue, and quality of life. Objective sleep was measured throughout one night using the wearable Philips Actiwatch. Upper limb motor performance was assessed on the following day and saliva was collected for biomarker analysis. Correlation analyses were performed to assess the relationships between variables. RESULTS: Participants reported poor sleep quality, frequent awakenings, and difficulties falling asleep following stroke. We identified a significant negative relationship between fatigue severity and both sleep quality (r=-0.539, p = 0.021) and participants experience of awakening from sleep (r=-0.656, p = 0.003). A significant positive relationship was found between grip strength on the non-hemiplegic limb and salivary gene expression of Brain-derived Neurotrophic Factor (r = 0.606, p = 0.028), as well as a significant negative relationship between grip strength on the hemiplegic side and salivary gene expression of C-reactive Protein (r=-0.556, p = 0.048). CONCLUSION: The findings of this study emphasize the importance of considering sleep quality, fatigue, and biomarkers in stroke rehabilitation to optimize recovery and that interventions may need to be tailored to the individual. Future longitudinal studies are required to explore these relationships over time. Integrating wearable technology for sleep and biomarker analysis can enhance monitoring and prediction of outcomes following stroke, ultimately improving rehabilitation strategies and patient outcomes.

Multi-session training in the evening schedule exhibits enhanced speech learning.

Speech learning can be influenced by a variety of factors. A growing body of literature suggests a significant influence of sleep on speech learning, i.e., those trained in the evening outperform those trained in the morning most probably due to consolidation of learning that happens during the sleep for the evening group. Since, learning, in general, may be a process that spans multiple sessions, in the current exploratory study, we aimed at investigating the effect of a multi-session training paradigm on the learning performance of the morning vs evening group. We compared young adults who were trained in the morning (8-10 am; n = 16) with those who were trained in the evening (6-8 pm; n = 16) on a Hindi dental-retroflex pseudoword-picture association training paradigm. Overall, we found that the evening group learned to a larger extent both for the identification (on trained items) and discrimination (on untrained items) tasks. The current findings, even with a multi-session paradigm, are consistent with the previous findings that support enhanced performance by training in the evening. These findings may have clinical implications toward scheduling of speech therapy.

Sleeping and waking-state oral behaviors in TMD patients: their correlates with jaw functional limitation and psychological distress.

OBJECTIVES: This study investigated oral behaviors in various temporomandibular disorder (TMD) subtypes, assessing their frequency, extent, and associations with both jaw functional status and psychological distress. MATERIALS AND METHODS: Anonymized data from consecutive "initial-visit" TMD patients at a university-affiliated oral medicine clinic were obtained. Alongside demographic information, patients completed various questionnaires including the Diagnostic Criteria for TMD (DC/TMD) Symptom Questionnaire, Oral Behavior Checklist (OBC), Jaw Functional Limitation Scale-20 (JFLS-20), Patient Health Questionnaire-9 (PHQ-9), and General Anxiety Disorder Scale-7 (GAD-7). Patients underwent a protocolized clinical examination and received diagnoses of pain-related (PT), intra-articular (IT), or combined (CT) TMD using the DC/TMD diagnostic algorithms. Data were evaluated with Chi-square/non-parametric tests and logistic regression analyses (α = 0.05). RESULTS: The study comprised 700 patients (mean age 37.4 ± 15.7 years), with 12.6%, 15.1%, and 72.3% diagnosed with PT, IT, and CT, respectively. For all TMD subtypes, oral activities during sleep were more prevalent than those during wakefulness. While variations in total/subscale OBC scores were insignificant, substantial differences were observed in global/subscale JFLS (PT, CT > IT), depression (PT, CT > IT), and anxiety (CT > IT) scores. Near-moderate correlations (rs = 0,36-0.39) were discerned between overall/waking-state non-functional oral behaviors and depression/anxiety. Multivariate analysis indicated that the odds of different TMD subtypes were influenced by sex, age, and jaw functional status. CONCLUSIONS: For all TMD patients, sleep-related oral activities were more commonly reported than waking-state activities. Factors such as sex, age, and jaw functional limitation are associated with the likelihood of different TMD subtypes. STATEMENT OF CLINICAL RELEVANCE: Oral behaviors, in themselves, do not predict distinct TMD subtypes, in contrast to factors such as sex, age, and jaw functional status.

Effects of respiratory exercises in sleep bruxism and associated obstructive sleep apnea: a double-blind, placebo-controlled randomized clinical trial.

PURPOSE: The aim of this study is to assess the effects of respiratory exercises (inspiratory and expiratory) in individuals with sleep bruxism (SB) and associated obstructive sleep apnea (OSA). METHODS: This is a double-blind, placebo-controlled randomized clinical trial including individuals with SB and associated respiratory events in OSA. Respiratory physical therapy was performed using inspiratory (Threshold® IMT), expiratory (Threshold® PEP) muscle training, and compared with a placebo group. A total of 30 daily respiratory cycles (inspiration and expiration) were performed five times a week for 12 weeks. Individuals were reassessed at two times, at baseline (T1) and after 12 weeks of training (T2) by means of the Pittsburgh Sleep Quality Index and Polysomnography. RESULTS: Awakening was significantly different (p ≤ 0.05) between the inspiratory group and placebo 12 weeks after respiratory physical therapy. The number of contractions of the masseter muscle differed between the inspiratory, expiratory, and placebo groups (p ≤ 0.05). CONCLUSION: Respiratory physical therapy for OSA improved awaking levels in 80 and 67% of the number of masseter muscle contractions, when compared to placebo. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials (No. RBR-9F6JKM).

Correlations between sleep architecture and sleep-related masseter muscle activity in children with sleep bruxism.

BACKGROUND: Sleep bruxism (SB) occurring during No-REM (nREM) sleep and increase in microarousals per hour have been described in adults, but not in children. OBJECTIVE: To assess the correlation between sleep architecture and masseter muscle activity related to sleep bruxism (SB/MMA) in children. MATERIALS AND METHODS: Forty-three children aged 7-12 years (mean age: 9.4 ± 1.3) with confirmed SB underwent a two-night polysomnographic (PSG) study in a sleep laboratory, for accommodation (first night) and data collection (second night). Data on sleep architecture (total sleep duration (TSD), sleep efficiency (SE), sleep onset latency (SOL), REM and nREM sleep duration and proportion and microarousals/hour during REM and nREM sleep) and episodes/hour of SB/MMA were recorded. Single and multiple-variable linear regression analyses were performed to assess the correlation between data on sleep architecture (predictors) and SB/MMA (dependent variable). RESULTS: Shorter TSD, REM and nREM stage 1 sleep duration, longer SOL and more microarousals/hour during REM and nREM sleep were found to be positive predictors of SB/MMA in children in the multiple-variable regression analysis (R2  = 0.511). CONCLUSION: Within the limitations of this study, it can be concluded that SB/MMA is correlated with altered sleep architecture in children (shorter total sleep duration (TSD), shorter nREM and REM sleep and higher microarousals during REM and nREM sleep). Nevertheless, the clinical significance of these findings need to be demonstrated in future studies.

Reciprocal first night effect on rhythmic and non-rhythmic oromotor episodes in moderate to severe primary sleep bruxism: A retrospective physiological study.

BACKGROUND: Sleep on the first night in a sleep laboratory is characterized by a lower sleep quality and frequency of rhythmic masticatory muscle activity (RMMA) than that on the second night in moderate to severe sleep bruxism (SB) patients. OBJECTIVE: The aims of this study was to clarify the physiological factors contributing to the first night effect on oromotor activity during sleep and investigate whether physiological factors involved in the first night effect differed between rhythmic and non-rhythmic oromotor activities. METHODS: Polysomnographic data collected on two consecutive nights from 15 moderate to severe SB subjects (F 7: M 8; age: 23.2 ± 1.3 [mean ± SD] years) were retrospectively analysed. Sleep variables, RMMA and non-specific masticatory muscle activity (NSMA) were scored in relation to episode types (i.e. phasic or tonic and cluster or isolated), sleep architecture and transient arousals. The relationships between nightly differences in oromotor and sleep variables were assessed. The distribution of oromotor events, arousals, cortical electroencephalographic power, RR intervals and heart rate variability were examined in relation to sleep cycle changes. These variables were compared between the first and second nights and between RMMA and NSMA. RESULTS: Sleep variables showed a lower sleep quality on Night 1 than on Night 2. In comparisons with Night 1, the RMMA index increased by 18.8% (p < .001, the Wilcoxon signed-rank test) on Night 2, while the NSMA index decreased by 17.9% (p = .041). Changes in the RMMA index did not correlate with those in sleep variables, while changes in the NSMA index correlated with those in arousal-related variables (p < .001, Spearman's rank correlation). An increase in the RMMA index on Night 2 was found for the cluster type and stage N1 related to sleep cyclic fluctuations in cortical and cardiac activities. In contrast, the decrease in the NSMA index was associated with increases in the isolated type and the occurrence of stage N2 and wakefulness regardless of the sleep cycle. CONCLUSION: Discrepancies in first night effect on the occurrence of RMMA and NSMA represent unique sleep-related processes in the genesis of oromotor phenotypes in SB subjects.

Sleep architecture as a candidate for phenotyping sleep bruxism: A narrative physiological review.

BACKGROUND: Sleep bruxism (SB), an oral behaviour in otherwise healthy individuals, is characterised by frequent rhythmic masticatory muscle activity (RMMA) during sleep. RMMA/SB episodes occur over various sleep stages (N1-N3 and rapid eye movement (REM)), sleep cycles (non-REM to REM), and frequently with microarousals. It currently remains unclear whether these characteristics of sleep architecture are phenotype candidates for the genesis of RMMA/SB. OBJECTIVES: This narrative review investigated the relationship between sleep architecture and the occurrence of RMMA as a SB phenotype candidate. METHODS: PubMed research was performed using keywords related to RMMA/SB and sleep architecture. RESULTS: In non-SB and SB healthy individuals, RMMA episodes were most frequent in the light non-REM sleep stages N1 and N2, particularly during the ascending phase of sleep cycles. The onset of RMMA/SB episodes in healthy individuals was preceded by a physiological arousal sequence of autonomic cardiovascular to cortical activation. It was not possible to extract a consistent sleep architecture pattern in the presence of sleep comorbidities. The lack of standardisation and variability between subject complexified the search for specific sleep architecture phenotype(s). CONCLUSION: In otherwise healthy individuals, the genesis of RMMA/SB episodes is largely affected by oscillations in the sleep stage and cycle as well as the occurrence of microarousal. Furthermore, a specific sleep architecture pattern cannot be confirmed in the presence of sleep comorbidity. Further studies are needed to delineate sleep architecture phenotype candidate(s) that contribute to the more accurate diagnosis of SB and treatment approaches using standardised and innovative methodologies.