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.

Tongue pressure is a strong predictor of recommendation for gastrostomy in amyotrophic lateral sclerosis.

INTRODUCTION/AIMS: Objective and practical biomarkers to determine the need for gastrostomy in patients with amyotrophic lateral sclerosis (ALS) are lacking. Tongue pressure (TP) is a promising biomarker because it is associated with bulbar dysfunction. The aims of this study were to evaluate the association of TP with the need for gastrostomy, and to determine its optimal cut-off value. METHODS: This prospective observational study included participants with ALS taking nutrition orally. TP was evaluated using the Iowa Oral Performance Instrument. Need for gastrostomy as determined by a multidisciplinary team during a 12-month follow up period was recorded. Associations between TP and need for gastrostomy placement were performed. ROC curve analysis determined the optimal cut-off value of TP to predict gastrostomy. RESULTS: Of 208 screened participants, 119 were included. Gastrostomy was indicated in 45% (53), in a 12-month follow up period. TP of ≤20 kPA was a strong predictor of gastrostomy indication (OR 11.8, CI 95% [4.61, 34.7], p < .001). The association persisted even after adjustment for weight loss, pneumonia, prolonged feeding duration, Revised ALS Functional Rating Scale score, and American Speech-Language-Hearing Association scale score (OR 4.51, CI 95% [1.50, 14.9], p = .009). By receiver operating characteristic curve analysis, 20 kPA represented the optimal cut-off value (sensitivity 0.75, specificity 0.89). DISCUSSION: TP is a strong independent predictor of gastrostomy indication in the subsequent 12 months in patients with ALS, with good sensitivity and specificity at a cutoff value of ≤20 kPA, suggesting that it may be a promising biomarker in clinical practice.

The role of atypical deglutition in children and adolescents with moderate to severe obstructive sleep apnea syndrome.

This cross-sectional study aimed to assess the prevalence of atypical deglutition (tongue thrust) in children diagnosed with moderate to severe obstructive sleep apnea syndrome (OSAS) and to explore its associations, particularly in relation to the type of dentition (mixed or permanent). The study was conducted over a 5 year period at a paediatric hospital in Paris, France. Children aged 6-18 years with moderate to severe OSAS (apnea-hypopnea index ≥5/h) underwent a comprehensive evaluation, including the recording of demographic data, symptoms of snoring and breathing issues, and otolaryngology examination. The swallowing pattern was assessed and orthodontic evaluations were performed. Cephalometric radiography and pharyngometry tests (pharyngeal collapsibility was computed) were conducted. The study found a high prevalence of atypical deglutition in children with mixed 74% [56-87] or permanent 38% [25-51] dentition. In children with mixed dentition and atypical deglutition, the pharyngeal compliance and lower facial dimensions were increased. In children with permanent dentition, atypical deglutition was associated with more severe OSAS and a lower hyoid bone position. Independent of the type of dentition, atypical deglutition was associated with an increase in the apnea-hypopnea index, an increase in the lower facial dimension, increased pharyngeal compliance, and a more caudal hyoid bone position. Atypical deglutition was strongly associated with increased pharyngeal collapsibility, more severe OSAS and altered facial measurements in children. The findings suggest that identifying atypical deglutition in children with OSAS could help to guide a personalised therapeutic approach, including myofunctional therapy.

Association Between Tongue Pressure and Prevalence of Mild Cognitive Impairment in Japan.

OBJECTIVE: Although it has been suggested that a decline in oral function is one of the potential risk factors affecting mild cognitive impairment (MCI), evidence is insufficient to draw clear conclusions. This Japanese cross-sectional study examined the association between tongue pressure (TP) and MCI in middle-aged and older adults aged 36-84 years. METHODS: Study participants were 1019 (368 men and 651 women). TP was evaluated using a TP measurement device. The maximum value of three measurements was used for analysis. MCI was defined as being present if a participant had a Japanese version of the Montreal Cognitive Assessment score of <26. Adjustment was made for age, smoking status, alcohol consumption, leisure-time physical activity, body mass index, hypertension, dyslipidemia, diabetes mellitus, history of depression, number of teeth, employment, education, and household income. RESULTS: The prevalence of MCI was 45.3%. Among women, compared with the lowest tertile of TP, the second and highest tertiles were significantly associated with a lower prevalence of MCI with a clear dose-response relationship; the adjusted odds ratio (95% confidence intervals) in the second and highest tertiles of TP were 0.54 (0.36-0.83) and 0.55 (0.36-0.84), respectively (p for trend = 0.005). In contrast, no statistically significant association was observed between TP and the prevalence of MCI among men. CONCLUSIONS: Our findings suggest that higher TP might be inversely associated with the prevalence of MCI in middle-aged and older Japanese women.

Association between swallowing dynamics, tongue pressure and pulmonary function in patients with idiopathic pulmonary fibrosis.

BACKGROUND: Swallowing is a complex process that requires the coordination of muscles in the mouth, pharynx, larynx, and esophagus. Dysphagia occurs when a person has difficulty swallowing. In the case of subjects with respiratory diseases, the presence of oropharyngeal dysphagia potentially increases lung disease exacerbations, which can lead to a rapid decline in lung function. This study aimed to analyze the swallowing of patients with idiopathic pulmonary fibrosis (IPF). METHODS: Patients with IPF were evaluated using the Eating Assessment Tool (EAT-10), tongue pressure, the Timed Water Swallow Test (TWST), and the Test of Mastication and Swallowing Solids (TOMASS). The findings were related to dyspnea severity assessed by the modified Medical Research Counsil (mMRC) score; the nutritional status screened with Mini Nutritional Assessment (MNA) tool; and pulmonary function tests, specifically spirometry and measurement of the diffusing capacity for carbon monoxide (DLCO), the maximal inspiratory pressure (PImax), and the maximal expiratory pressure (PEmax). RESULTS: The sample consisted of 34 individuals with IPF. Those who exhibited swallowing modifications scored lower on the MNA than those who did not (9.6 ± 0.76 vs. 11.64 ± 0.41 points; mean difference 1.98 ± 0.81 points; p = 0.02). They also showed poorer lung function when considering the predicted force vital capacity (FVC; 81.5% ± 4.61% vs. 61.87% ± 8.48%; mean difference 19.63% ± 9.02%; p = 0.03). The speed of liquid swallowing was altered in 31of 34 of the evaluated subjects (91.1%). The number of liquid swallows correlated significantly with the forced expiratory volume in 1 s (FEV1)/FVC ratio (r = 0.3; p = 0.02). Solid eating and swallowing assessed with the TOMASS score correlated with lung function. The number of chewing cycles correlated negatively with PImax% predicted (r = -0.4; p = 0.0008) and PEmax% predicted (r = -0.3; p = 0.02). FVC% predicted correlated with increased solid swallowing time (r = -0.3; p = 0.02; power = 0.6). Swallowing solids was also impacted by dyspnea. CONCLUSION: Patients with mild-to-moderate IPF can present feeding adaptations, which can be related to the nutritional status, lung function, and the severity of dyspnea.

Association of Tongue Strength and Maximum Incisal Opening with Oral Intake in Persons with Head and Neck Cancer Treated with Radiotherapy: A Retrospective Study.

Persons treated with radiotherapy (RT) for cancer of the head and neck (HNC) may experience limited oral intake at treatment completion. The purpose of this retrospective study was to examine the contributions of tongue strength and maximum incisal opening (MIO) to oral intake in a cohort of veterans treated for HNC. Medical records of veterans diagnosed with HNC treated with RT who were seen by the Speech Pathology Service prior to and throughout treatment per usual care were reviewed for this study; eighty-two records met the inclusion criteria for analysis. Tongue strength in kPa, MIO in mm, feeding tube status at completion of RT, and food and liquid consistencies consumed at completion of RT were among the data abstracted from the records. Most veterans (67%) did not have a feeding tube present at the completion of RT and reported drinking thin liquids (84.2%) at treatment completion. Eighteen percent reported including all food consistencies in their diet at the end of treatment. Both MIO and tongue strength decreased after treatment. Greater tongue strength during RT and larger MIO at the completion of RT were predictive of improved functional outcomes for oral intake at the end of treatment. This study provides evidence of the importance of increasing tongue strength and MIO during treatment with RT, and supports an important focus for intervention by speech-language pathologists.

Correlation between oral muscle pressure and malocclusion in mixed dentition: a cross-sectional study.

OBJECTIVE: To investigate the relationship between oral muscle pressure and malocclusion in the mixed dentition. MATERIALS AND METHODS: Maximum tongue, lip and cheek pressure was measured using the Iowa Oral Performance Instrument (IOPI) in 3 patient cohorts: patients with (1) posterior crossbite, (2) class II relationship and (3) a control group of patients without malocclusion. Linear models were used to compare the mean differences in muscle pressure between groups, with correction for age and gender. The imbalance between lips and tongue and between lips and cheeks was calculated by the Delta z-scores of each group. RESULTS: A total of 146 participants were included, 46 (mean age 8.71±0.85), 41 (mean age 11.74±1.17) and 35 (mean age 10.71±1.92) in groups 1, 2 and 3 respectively. Patients with malocclusion showed significantly higher lip and lower cheek pressure and imbalance favouring the lips over the tongue compared to controls. Class II,1 patients showed significantly higher tongue pressure than Class II,2. No differences were found in muscle pressure or imbalance between crossbite and Class II nor between crossbite types. CONCLUSION AND CLINICAL RELEVANCE: These findings suggest that oral muscle pressure may be associated with malocclusion. This highlights the importance of functional diagnosis and its implications on the prevention and treatment of malocclusion, as well as on orthodontic stability.

Impact of frenectomy on the oral exercise in patients with ankyloglossia and obstructive sleep apnea: double-blind randomized controlled clinical trials.

OBJECTIVE: This study compares the efficacy of oral exercise alone to oral exercise with frenectomy in improving obstructive sleep apnea (OSA) symptoms and quality of life (QOL) in patients with ankyloglossia. MATERIALS AND METHODS: A prospective, controlled, double-blind clinical study enrolled fifteen adults (20-60 years) newly diagnosed with mild to moderate OSA and ankyloglossia. Participants were randomly assigned to either oral exercise alone (control group; n = 8) or oral exercise with frenectomy (intervention group; n = 7). Outcomes were assessed after a 3-month therapy period using polysomnography, the Epworth Sleepiness Scale (ESS), tongue strength (measured in kPa), and QOL questionnaires. RESULTS: Both control (-2.88 ± 1.73; p = 0.02) and intervention (-4.00 ± 3.65; p = 0.03) groups showed a significant reduction in ESS scores, indicating both improved sleepiness. Although the apnea-hypopnea index (AHI) increased in both groups after treatment, these changes were not statistically significant (control 4.73 ± 15.55; p = 0.48, intervention 10.42 ± 14.66; p = 0.12). Tongue strength significantly increased in both groups: control group (p = 0.04) and intervention group (p = 0.03). Satisfaction rates with the overall treatment process were 100% in the control group and 57.1% in the intervention group. Furthermore, 75.0% and 57.1% of participants in the respective groups reported an improvement in QOL. CONCLUSION: Frenectomy improved tongue mobility and the ability to perform oral exercises in individuals with OSA and ankyloglossia. However, these exercises did not significantly improve OSA-related symptoms or QOL. CLINICAL RELEVANCE: While frenectomy enhances tongue mobility, thereby enabling better engagement in oral exercises. These exercises alone did not significantly improve OSA-related symptoms or QOL. This suggests that oral exercises focusing solely on tongue mobility may not be sufficient for managing OSA. TRIAL REGISTRATION: The Thai Clinical Trials Registry was TCTR20220429002.

Severity of tongue base collapse in various body positions in patients with obstructive sleep apnea: A trajectory analysis.

BACKGROUND: Drug-induced sleep endoscopy (DISE) is used for evaluating upper airway anatomy and determining airway obstruction patterns. It is typically performed with the patient in the supine position. Airway collapse severity is influenced by body position and level of consciousness; the resultant dynamic changes may vary across patients. In this study, we evaluated the severity of upper airway collapse through awake endoscopy and DISE and identified factors affecting the pattern of airway collapse severity. METHODS: This study included 66 patients with obstructive sleep apnea. The patients underwent type 1 polysomnography, tongue strength assessment, awake endoscopy in the sitting and supine positions, and DISE. Group-based trajectory modeling was performed to identify patients with different collapse severity patterns in different body positions and at different levels of consciousness. RESULTS: Patient with similar severity trajectory were assigned to the same group. Two different severity trajectories (group 1 and group 2) were identified at the tongue base level. Tongue depression strength varied significantly between groups 1 and 2 (47.00 vs. 35.00 kPa; P = .047). During awake endoscopy, collapse severity was significantly higher in group 2 than in group 1. Group 1 had lower rapid eye movement/nonrapid eye movement apnea-hypopnea index ratios and higher tongue depression strength than did group 2. CONCLUSION: In patients with obstructive sleep apnea, tongue strength may vary depending on body position. Our results should be interpreted with caution because of the limited sample size. Future studies should investigate the effect of oropharyngeal rehabilitation on tongue strength and collapse severity.

Tongue pressure and maxillofacial muscle activities during swallowing in patients with mandibular prognathism.

BACKGROUND: Coordination among lip, cheek and tongue movements during swallowing in patients with mandibular prognathism remains unclear. OBJECTIVES: This study aimed to identify the temporal sequences of tongue pressure and maxillofacial muscle activities during swallowing in patients with mandibular prognathism and compared characteristics with those of healthy volunteers. METHODS: Seven patients with mandibular prognathism (mandibular prognathism group) and 25 healthy volunteers with individual normal occlusion (control group) were recruited. Tongue pressures and masseter, orbicularis oris, mentalis and supra- and infrahyoid muscle activities while swallowing gel were measured simultaneously using a sensor sheet system with five measurement points and surface electromyography, respectively. Onset time, offset time and durations of tongue pressure and muscle activities were analysed. RESULTS: In the mandibular prognathism group, tongue pressure was often produced first in more peripheral parts of the palate. Offset of tongue pressure in the posteromedian and peripheral parts of the palate and maxillofacial muscle activities except for orbicularis oris were delayed. Duration of tongue pressure in the anteromedian part of the palate was significantly shorter and durations of masseter, mentalis and suprahyoid muscle activities were significantly longer. Times to onset of orbicularis oris and suprahyoid muscle activities based on first onset of tongue pressure were significantly shorter. CONCLUSION: These results suggest that patients with mandibular prognathism may exhibit specific patterns of tongue pressure production and maxillofacial muscle activities during swallowing.

A mandibular advancement device attenuates the abnormal morphology and function of mitochondria from the genioglossus in obstructive sleep apnea-hypopnea syndrome rabbits.

BACKGROUND: Obstructive sleep apnea hypopnea syndrome (OSAHS) is a serious and potentially life-threatening disease. Mandibular advancement device (MAD) has the characteristics of non-invasive, comfortable, portable and low-cost, making it the preferred treatment for mild-to-moderate OSAHS. Our previous studies found that abnormal contractility and fibre type distribution of the genioglossus could be caused by OSAHS. However, whether the mitochondria participate in these tissue changes is unclear. The effect of MAD treatment on the mitochondria of the genioglossus in OSAHS is also uncertain. OBJECTIVE: To examine the morphology and function of mitochondria from the genioglossus in a rabbit model of obstructive sleep apnea-hypopnea syndrome (OSAHS), as well as these factors after insertion of a mandibular advancement device (MAD). METHODS: Thirty male New Zealand white rabbits were randomised into three groups: control, OSAHS and MAD, with 10 rabbits in each group. Animals in Group OSAHS and Group MAD were induced to develop OSAHS by injection of gel into the submucosal muscular layer of the soft palate. The rabbits in Group MAD were fitted with a MAD. The animals in the control group were not treated. Further, polysomnography (PSG) and cone-beam computed tomography (CBCT) scan were used to measure MAD effectiveness. CBCT of the upper airway and PSG suggested that MAD was effective. Rabbits in the three groups were induced to sleep for 4-6 h per day for eight consecutive weeks. The genioglossus was harvested and detected by optical microscopy and transmission electron microscopy. The mitochondrial membrane potential was determined by laser confocal microscopy and flow cytometry. Mitochondrial complex I and IV activities were detected by mitochondrial complex assay kits. RESULTS: OSAHS-like symptoms were induced successfully in Group OSAHS and rescued by MAD treatment. The relative values of the mitochondrial membrane potential, mitochondrial complex I activity and complex IV activity were significantly lower in Group OSAHS than in the control group; however, there was no significant difference between Group MAD and the control group. The OSAHS-induced injury and the dysfunctional mitochondria of the genioglossus muscle were reduced by MAD treatment. CONCLUSION: Damaged mitochondrial structure and function were induced by OSAHS and could be attenuated by MAD treatment.

Mastication and oral myofunctional status in excess weight children and adolescents: A cross-sectional observational study.

BACKGROUND: Masticatory function seems to play a role in the aetiology of obesity. However, literature on the association between oral myofunctional status and overweight and obesity in children and adolescents is scarce and contrasting. OBJECTIVE: To compare masticatory performance, orofacial myofunctional status and tongue strength and endurance between children and adolescents with overweight and obesity and those with normal weight. METHODS: Thirty children and adolescents with overweight and obesity and 30 subjects with normal weight matched for age and sex were recruited. All subjects were evaluated with the Test of Masticating and Swallowing Solids in Children (TOMASS-C) for masticatory performance and with the Italian Orofacial Myofunctional Evaluation with Scores (I-OMES) for the orofacial myofunctional status. Anterior and posterior maximum tongue pressures and tongue endurance were measured. Parents-reported (PRO) duration of meals was recorded. Data were compared between the groups through the paired samples t-test or the Wilcoxon signed-rank test. RESULTS: Children and adolescents with overweight showed significantly lower number of bites (p = .033), lower I-OMES scores (p < .05), and shorter meal duration (p = .005) compared to their peers with normal weight. No significant differences were found between the two groups for the number of swallows, the number of masticatory cycles and the total time of the TOMASS-C, and none of the tongue pressure measurements. CONCLUSIONS: Eating in children and adolescents with overweight and obesity is characterised by a larger bolus sizes and shorter PRO meal duration. Additionally, overweight and obesity seem to be associated with poorer orofacial skills and structures in the paediatric population.

Effect of home-based tongue-strengthening exercise using a portable tool on oropharyngeal muscles in older adults with sarcopenic dysphagia: A randomised controlled study.

BACKGROUND: Tongue-strengthening exercises may be used at home to strengthen swallowing-related oropharyngeal muscles in community-dwelling older adults with sarcopenic dysphagia; however, evidence of their effectiveness remains unclear. OBJECTIVE: This study aimed to investigate the effects of a home-based tongue-strengthening exercise (hTSE) using portable tool on swallowing-related oropharyngeal muscles in community-dwelling older adults with sarcopenic dysphagia. METHODS: Forth community-dwelling older adults with sarcopenic dysphagia were enrolled in the study. The participants were randomly assigned to the experimental and control groups. 1-Repetition Maximum (1-RM) of tongue muscle was measured in the experimental group using the Iowa Oral Performance Instrument, and hTSE was performed using a portable tool with an intensity corresponding to approximately 70%-80% of the range based on the 1-RM value (90 times/day, 5 days/week, for 8 weeks). The control group did not perform any tongue exercises. The primary outcome measures were tongue strength and thickness. The secondary outcome measure was suprahyoid muscle strength (digastric and mylohyoid muscles). RESULTS: The experimental group showed significantly greater increases in suprahyoid muscle (mylohyoid and digastric) thickness (p = .01 and .011, d = 1.0 and .55), as well as tongue strength and thickness (p < .001 and .029, d = 2.2 and .6) than the control group. CONCLUSION: This study confirmed that hTSE using a portable tool is effective in increasing swallowing-related oropharyngeal muscle activity in older adults with sarcopenic dysphagia. Therefore, hTSE is recommended as an inexpensive, safe, and easy-to-use therapy for sarcopenic dysphagia in older adults.

Improvement of oral function and its impact on oral food intake in subacute stroke patients: A prospective study with dental intervention.

BACKGROUND: The association between oral food intake and oral function during the subacute stage of stroke is not well known. OBJECTIVE: To investigate (1) oral function changes in subacute stroke patients and (2) association between oral function and oral intake status at several time points. METHODS: In a prospective study involving 324 stroke patients at a convalescent rehabilitation unit, four oral function parameters (maximum tongue pressure, MTP; lip-tongue motor function, LTMF; maximum occlusal force, MOF and oral health assessment tool, OHAT) were quantitatively measured upon admission (T0), at 1 month (T1) and 2 months (T2). Oral feeding status was assessed using the Functional Oral Intake Scale (FOIS) and divided based on the FOIS score into the dysphagic and regular diet groups. The changes in oral functions at the three time points were tested using generalized estimating equation analysis. The association between FOIS groups and oral functions at T1 and T2 was analysed by means of logistic regression analysis. RESULTS: All oral function parameters improved significantly over time during the hospital stay (mean differences: 4.9 for MTP, 0.6 for LTMF, 1.1 for MOF and -1.8 for OHAT). The FOIS groups were significantly associated with MTP (p < .05) and OHAT (p < .05) at both T1 and T2. CONCLUSION: Our findings suggest that oral function significantly improves in patients during subacute stroke rehabilitation and better oral health can be associated with better oral intake. Improved oral function through dental intervention and oral rehabilitation may contribute to gains in oral food intake.

Ventilatory Drive Withdrawal Rather Than Reduced Genioglossus Compensation as a Mechanism of Obstructive Sleep Apnea in REM Sleep.

Rationale: REM sleep is associated with reduced ventilation and greater obstructive sleep apnea (OSA) severity than non-REM (nREM) sleep for reasons that have not been fully elucidated. Objectives: Here, we use direct physiological measurements to determine whether the pharyngeal compromise in REM sleep OSA is most consistent with 1) withdrawal of neural ventilatory drive or 2) deficits in pharyngeal pathophysiology per se (i.e., increased collapsibility and decreased muscle responsiveness). Methods: Sixty-three participants with OSA completed sleep studies with gold standard measurements of ventilatory "drive" (calibrated intraesophageal diaphragm EMG), ventilation (oronasal "ventilation"), and genioglossus EMG activity. Drive withdrawal was assessed by examining these measurements at nadir drive (first decile of drive within a stage). Pharyngeal physiology was assessed by examining collapsibility (lowered ventilation at eupneic drive) and responsiveness (ventilation-drive slope). Mixed-model analysis compared REM sleep with nREM sleep; sensitivity analysis examined phasic REM sleep. Measurements and Main Results: REM sleep (⩾10 min) was obtained in 25 patients. Compared with drive in nREM sleep, drive in REM sleep dipped to markedly lower nadir values (first decile, estimate [95% confidence interval], -21.8% [-31.2% to -12.4%] of eupnea; P < 0.0001), with an accompanying reduction in ventilation (-25.8% [-31.8% to -19.8%] of eupnea; P < 0.0001). However, there was no effect of REM sleep on collapsibility (ventilation at eupneic drive), baseline genioglossus EMG activity, or responsiveness. REM sleep was associated with increased OSA severity (+10.1 [1.8 to 19.8] events/h), but this association was not present after adjusting for nadir drive (+4.3 [-4.2 to 14.6] events/h). Drive withdrawal was exacerbated in phasic REM sleep. Conclusions: In patients with OSA, the pharyngeal compromise characteristic of REM sleep appears to be predominantly explained by ventilatory drive withdrawal rather than by preferential decrements in muscle activity or responsiveness. Preventing drive withdrawal may be the leading target for REM sleep OSA.

Brain-derived neurotrophic factor overexpression in taste buds diminishes chemotherapy induced taste loss.

Vismodegib is used in patients suffering from advanced basal cell carcinoma (BCC), but 100% of the patients taking it report dysgeusia and 50% discontinue the treatment. Treatment with neurotrophic factors can stimulate neuronal survival and functional improvement in injured organs. Here, we analysed novel transgenic mouse lines in which brain-derived neurotrophic factor (BDNF) is overexpressed in taste buds, to examine whether higher levels of BDNF would reduce or prevent negative side effects of vismodegib in the taste system. BDNF plays crucial roles for development, target innervation, and survival of gustatory neurons and taste buds. The behavioural test in this study showed that vehicle-treated wild-type mice prefered 10 mM sucrose over water, whereas vismodegib treatment in wild-type mice caused total taste loss. Gustducin-BDNF mice had a significantly increased preference for low concentration of sucrose solution over water compared to wild-type mice, and most importantly the transgenic mice were able to detect low concentrations of sucrose following vismodegib treatment. We evaluated taste cell morphology, identity, innervation and proliferation using immunohistochemistry. All drug-treated mice exhibited deficits, but because of a possible functional upcycled priming of the peripheral gustatory system, GB mice demonstrated better morphological preservation of the peripheral gustatory system. Our study indicates that overexpression of BDNF in taste buds plays a role in preventing degeneration of taste buds. Counteracting the negative side effects of vismodegib treatment might improve compliance and achieve better outcome in patients suffering from advanced BCC.

Tongue weakness and atrophy differentiates late-onset Pompe disease from other forms of acquired/hereditary myopathy.

Late-onset Pompe disease (LOPD) is an inherited autosomal recessive progressive metabolic myopathy that presents in the first year of life to adulthood. Clinical presentation is heterogeneous, differential diagnosis is challenging, and diagnostic delay is common. One challenge to differential diagnosis is the overlap of clinical features with those encountered in other forms of acquired/hereditary myopathy. Tongue weakness and imaging abnormalities are increasingly recognized in LOPD. In order to explore the diagnostic potential of tongue involvement in LOPD, we assessed tongue structure and function in 70 subjects, including 10 with LOPD naive to treatment, 30 with other acquired/hereditary myopathy, and 30 controls with neuropathy. Tongue strength was assessed with both manual and quantitative muscle testing. Ultrasound (US) was used to assess tongue overall appearance, echointensity, and thickness. Differences in tongue strength, qualitative appearance, echointensity, and thickness between LOPD subjects and neuropathic controls were statistically significant. Greater tongue involvement was observed in LOPD subjects compared to those with other acquired/hereditary myopathies, based on statistically significant decreases in quantitative tongue strength and sonographic muscle thickness. These findings provide additional evidence for tongue involvement in LOPD characterized by weakness and sonographic abnormalities suggestive of fibrofatty replacement and atrophy. Findings of quantitative tongue weakness and/or atrophy may aid differentiation of LOPD from other acquired/hereditary myopathies. Additionally, our experiences in this study reveal US to be an effective, efficient imaging modality to allow quantitative assessment of the lingual musculature at the point of care.

Prevalence and patterns of tongue deformation in obstructive sleep apnea: A whole-night simultaneous ultrasonographic and polysomnographic study.

Tongue deformation during whole-night natural sleep in adult patients with obstructive sleep apnea has not been well evaluated. Through simultaneous ultrasonography and polysomnography during whole-night sleep, we examined the prevalence and patterns of tongue depth changes and their relationship with the severity of obstructive sleep apnea. Sixty consecutive eligible adults presenting with symptoms suggesting obstructive sleep apnea were enrolled. We observed that 88.4% (38/43) of patients with obstructive sleep apnea exhibited a significant increase in the maximum ultrasonographic tongue depth when hypopnea or apnea occurred during sleep. A mixed-model analysis of variance demonstrated that compared with patients with primary snoring or mild obstructive sleep apnea, those with moderate to severe obstructive sleep apnea have significantly greater maximum ultrasonographic tongue depth during respiratory events (p = .0047). We identified three different ultrasonographic patterns of tongue deformation, namely en bloc, tongue body and tongue base. Approximately 82% (27/33) of patients with moderate to severe obstructive sleep apnea demonstrated an en bloc tongue deformation. By contrast, 70% (19/27) of primary snorers or patients with mild obstructive sleep apnea showed a tongue body obstruction. Recognizing the prevalence and patterns of tongue deformation during sleep may provide insights into pathogenesis and treatment decisions in patients with obstructive sleep apnea. Future studies are warranted to verify the treatment results of various tongue procedures by using this approach.

The role of mitophagy in the mechanism of genioglossal dysfunction caused by chronic intermittent hypoxia and the protective effect of adiponectin.

PURPOSE: Dysfunction of the genioglossus muscle is important in the pathogenesis of obstructive sleep apnea due to chronic intermittent hypoxia (CIH). Mitochondrial impairment resulting from hypoxia is mitigated by mitophagy to avoid cell apoptosis in cardiomyocytes. This project was designed to explore the effects of CIH on mitophagy in the genioglossus muscle and the impact of adiponectin (Ad). METHODS: One hundred eighty male SD rats were randomly divided into 3 groups (normal control [NC], CIH, and CIH + Ad groups), with 60 rats in each group observed for 5 weeks. Comparisons of serum Ad levels, mitochondrial structure and function, mitophagy, and cell apoptosis in the genioglossus were made at different time points. RESULTS: (1) The CIH group was significantly different from the NC group as follows: During the first 3 weeks, serum Ad levels, the reactive oxygen species (ROS), relative proteins and mRNA of mitophagy, autophagy biomarker LC3-II, and autophagosomes increased, while during the last 2 weeks, most parameters decreased. (2) There was no difference among the 3 groups in mitochondrial structure and function-associated mRNA during the first 3 weeks, while damaged mitochondrial structures were growing during the last 2 weeks. Exacerbation of apoptosis was also detected in the last 2 weeks. (3) All of the damage was partially alleviated in the CIH + Ad group in contrast to CIH group at the end of this study. CONCLUSION: Disturbances of genioglossal mitophagy could be related to damaged mitochondrial structure and function induced by CIH, which could be alleviated by supplementation of exogenous Ad via increasing mitophagy.

Dynamic tongue area measurements in ultrasound images for adults with obstructive sleep apnea.

Obstructive sleep apnea is a chronic breathing disorder where the recursive collapse of the upper airway causes cessation of airflow during sleep. Quantitative assessments of dynamic tongue motion may provide a better understanding of the mechanism of obstructive sleep apnea. Tongue area changes, in submental ultrasound images recorded during wakefulness from normal breathing by the Müller manoeuvre, were tracked using the modified optical flow-based method. The results demonstrated that patients with obstructive sleep apnea had a larger mid-sagittal tongue area compared to the control group (during normal breathing, p = .004, during the Müller manoeuvre p = .005, and differences between normal breathing and the Müller manoeuvre, p = .01). Tongue area measurements were significantly different in patients with varying severity of OSA during normal breathing and during the Müller manoeuvre, and had differences between normal breathing and the Müller manoeuvre (p = .005, p = .008 and p = .03, respectively). Patients with moderate or severe obstructive sleep apnea exhibited minimal movement of the tongue. In contrast, normal controls and patients with mild obstructive sleep apnea demonstrated bidirectional tongue motions during a transition from normal breathing to the Müller manoeuvre in wakefulness. Identifying different patterns of deformation and displacement of the tongue may have potential in evaluating the presence and the pathogenesis of OSA.