Differences in Positive Airway Pressure Requirements in Obstructive Sleep Apnea Between Black and White Patients.

OBJECTIVE: There are disparities between Black and White patients in the utilization of positive airway pressure (PAP) alternatives for obstructive sleep apnea (OSA). Given low utilization rates among Black patients, there is limited knowledge of PAP alternative outcomes in this group. Therapeutic PAP levels are clinically accessible measures that have been shown to predict PAP alternative outcomes. Herein, we examined differences in PAP requirements between Black and White patients in a large clinical sample. STUDY DESIGN: Cross-sectional. SETTING: Academic sleep center. METHODS: We included OSA patients prescribed autoadjusting PAP between January 2018 and 2020 with baseline apnea-hypopnea index (AHI) ≥ 10. Mean and 90th percentile PAP levels were compared between White and Black patients who used PAP for ≥1 hour daily using linear regression controlling for age, sex, body mass index (BMI), AHI, oxygen saturation nadir, and mask type. RESULTS: There were 157 Black and 234 White patients who were generally obese (BMI, 37.3 ± 8.7) with severe OSA (AHI, 36.9 ± 25.6). Black patients had a 0.68 cm higher (95% confidence interval [CI]: 0.36, 1.35) mean PAP level and 0.85 cm H2O higher (95% CI: 0.36, 1.35) 90th percentile PAP level than white patients. Although statistically significant, differences were small and not clinically meaningful. CONCLUSION: Black and White OSA patients had clinically insignificant differences in PAP requirements, suggesting comparable upper airway collapsibility. Considering the predictive value of therapeutic PAP levels, our findings suggest Black and White patients may have comparable PAP alternative responses from a collapsibility standpoint. Future studies should explore reasons for low utilization of PAP alternatives among Black patients.

The Repeatability of Pharyngeal Opening Pressure Under Drug-Induced Sleep Endoscopy.

OBJECTIVE: Pharyngeal opening pressure (PhOP) is a measure of upper airway collapsibility that can be obtained during drug-induced sleep endoscopy (DISE) using a continuous positive airway pressure (CPAP) titration. However, the stability of PhOP over the course of sedation during DISE remains unclear. This study aims to compare repeat measures of PhOP over the course of DISE. STUDY DESIGN: Single arm prospective study. SETTING: Single tertiary care institution. METHODS: Patients had 2 CPAP titrations while undergoing DISE. Collected data included patient demographics, PhOP, patient sedation index (PSI), and duration of and between CPAP titrations. t Tests, test-retest coefficient analysis, and repeated measures correlation were performed. RESULTS: Twenty-five patients completed the study between 2022 and 2023 with 22 patients having sedation depth (PSI) recording. Most were male (76%), obese (average body mass index: 30.24 kg/m2), with severe obstructive sleep apnea (average apnea-hypopnea index: 39.8 events/hr). Test-retest analysis showed good-excellent correlation between PhOP values (intraclass correlation coefficient = 0.892, P < .0001, n = 25). Average time between CPAP titrations was 15 minutes to 6 seconds. Over that time, PhOP increased by an average of 0.72 cmH2O (P = .06, n = 25) and PSI decreased by 9.5 units (P = .01, n = 22). Repeated measures correlation showed a weak negative correlation between PhOP and PSI (r = -.45, P = .03, n = 22). CONCLUSION: The results showed repeatability of PhOP values over the course of DISE. When adjusted for sedation depth (PSI), deeper sedation was weakly associated with greater PHOP. However, the magnitude of this change was small and we conclude that PhOP remains relatively stable over the course of DISE (Effects of Lung Volume on Upper Airway Patency During DISE [DISE-Pulm], NCT05350332, clinicaltrials.gov).

Posterior Palatal Expansion via Subnasal Endoscopy (2PENN) for Maxillary Deficiency: A Pilot Study.

OBJECTIVE: Surgically assisted rapid palatal expansion (SARPE) addresses transverse maxillary deficiency, a known contributor to nasal obstruction. The purpose of this study was to assess the feasibility, preliminary outcomes, and safety of posterior palatal expansion via subnasal endoscopy (2PENN), a modified SARPE procedure, aimed at achieving anterior and posterior maxillary expansion. METHODS: This prospective case series included consecutive adult patients with findings of transverse maxillary deficiency that underwent the 2PENN procedure from 4/2021 to 4/2022. Patients completed pre- and post-operative clinical evaluations, Nasal Obstruction and Septoplasty Effectiveness (NOSE) questionnaires, and computed tomography (CT), with measures including expansion at the level of the posterior nasal spine (PNS), first maxillary inter-molar distance (IMD), and anterior nasal spine (ANS). RESULTS: The cohort (N = 20) was middle-aged (39 ± 11 years), predominantly male (80%), and overweight (BMI 28 ± 4 kg/m2 ). The majority (85%) of patients had sleep breathing issues, of which 10 (59%) had polysomnography-confirmed obstructive sleep apnea (OSA). Full anterior-posterior separation of the mid-palatal suture line was evident on all post-operative CT scans, with mean expansion at the PNS of 3.6 ± 1.3 mm, IMD of 6.1 ± 1.6 mm and ANS of 7.0 ± 1.6 mm (p < 0.001). Following surgery, mean NOSE scores improved from 57 ± 23 to 14 ± 13 (p < 0.001). One patient required maxillary antrostomy for post-operative sinusitis. CONCLUSION: 2PENN is an effective and safe technique for achieving both anterior and posterior maxillary expansion in patients with transverse maxillary deficiency. Further study is warranted to better understand the effect of 2PENN in patients with OSA, particularly as it relates to improving pharyngeal patency. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:1970-1977, 2024.

The Accuracy and Reliability of Visually Assessed Pharyngeal Opening Pressures During Drug-Induced Sleep Endoscopy.

OBJECTIVE: To examine the accuracy and interrater reliability of a visually assessed vs airflow-based measure of pharyngeal collapsibility obtained in patients with obstructive sleep apnea undergoing drug-induced sleep endoscopy (DISE). STUDY DESIGN: Prospective observational study. SETTING: Academic tertiary care practice. METHODS: Patients underwent DISE with airflow monitoring and nasal positive airway pressure titration to determine visual and airflow-based levels of pharyngeal opening pressure (PhOP). Visual DISE-PhOP was assessed by 2 blinded independent raters and defined as the pressure at which visual confirmation of airway collapse, including snoring, was abolished. Airflow-based DISE-PhOP was defined as the minimally effective positive airway pressure that abolished inspiratory flow limitation. Equivalence testing between visual and airflow DISE-PhOP of each rater was performed with the two one sided T-test (TOST) with an a priori equivalence bound of ±1 cm H2 O. Interrater reliability was evaluated with the intraclass correlation coefficient. RESULTS: One hundred patients were enrolled in the study and 77 completed the full evaluation. The population was predominantly male (74%) with an average age of 54.8 years, body mass index of 30.1 kg/m2 , and apnea-hypopnea index of 30.7 events/h. Equivalence testing showed that both raters were within ±1 cm H2 O of airflow-based DISE-PhOP (-0.43 to 0.09 cm H2 O and -0.32 to 0.48 cm H2 O). Interrater reliability of visual DISE-PhOP between the raters was also good to excellent with an intraclass correlation coefficient of 0.895 (95% CI, 0.84-0.932). CONCLUSION: DISE-PhOP, a measure of upper airway collapsibility, was equivalent between airflow-based and visual assessments with strong interrater reliability, supporting its adoption as a standardized objective parameter in clinical DISE.

The role of craniofacial maldevelopment in the modern OSA epidemic: a scoping review.

OBJECTIVES: There is increasing recognition that environmental factors affect human craniofacial development and our risk for disease. A scoping review of the literature was performed looking at environmental influences on craniofacial development to better understand this relationship and investigate what further study is needed to determine how this relationship may impact obstructive sleep apnea. METHODS: A comprehensive literature search was performed using the Ovid Medline database from inception to May 2020 with relevance to craniofacial development in 5 clinically oriented variables: diet, secular change, breastfeeding/nonnutritive sucking habits, nasal obstruction/mouth breathing, and masticatory muscle function. The Oxford Centre for Evidence-Based Medicine Levels of Evidence was used to assess studies based on study design. RESULTS: We initially identified 18,196 articles, of which 260 studies were fully reviewed and 97 articles excluded. The remaining 163 articles were categorized as follows: secular change (n = 16), diet (n = 33), breastfeeding/nonnutritive sucking habits (n = 28), nasal obstruction/mouth breathing (n = 57), and masticatory muscle function (n = 35). Ninety-three percent of included studies reported a significant association between craniofacial morphology and environmental factors. The majority of studies were characterized as low-level-of-evidence studies, with 90% of studies being a level-of-evidence of 4 or 5. CONCLUSIONS: The studies in this review suggest that environmental factors are associated with changes in craniofacial development. However, most studies were heterogeneous and low-level studies, making strong conclusions about these relationships difficult. Future rigorous studies are needed to further our understanding of environmental influences on craniofacial development and obstructive sleep apnea risk. CITATION: Yu JL, Tangutur A, Thuler E, Evans M, Dedhia RC. The role of craniofacial maldevelopment in the modern OSA epidemic: a scoping review. J Clin Sleep Med. 2022;18(4):1187-1202.

A comparison of ultrasound echo intensity to magnetic resonance imaging as a metric for tongue fat evaluation.

STUDY OBJECTIVES: Tongue fat is associated with obstructive sleep apnea (OSA). Magnetic resonance imaging (MRI) is the standard for quantifying tongue fat. Ultrasound echo intensity has been shown to correlate to the fat content in skeletal muscles but has yet to be studied in the tongue. The objective of this study is to evaluate the relationship between ultrasound echo intensity and tongue fat. METHODS: Ultrasound coronal cross-sections of ex-vivo cow tongues were recorded at baseline and following three 1 mL serial injections of fat into the tongue. In humans, adults with and without OSA had submental ultrasound coronal cross-sections of their posterior tongue. The average echo intensity of the tongues (cow/human) was calculated in ImageJ software. Head and neck MRIs were obtained on human subjects to quantify tongue fat volume. Echo intensity was compared to injected fat volume or MRI-derived tongue fat percentage. RESULTS: Echo intensity in cow tongues showed a positive correlation to injected fat volume (rho = 0.93, p < .001). In human subjects, echo intensity of the tongue base strongly correlated with MRI-calculated fat percentage for both the posterior tongue (rho = 0.95, p < .001) and entire tongue (rho = 0.62, p < .001). Larger tongue fat percentages (rho = 0.38, p = .001) and higher echo intensity (rho = 0.27, p = .024) were associated with more severe apnea-hypopnea index, adjusted for age, body mass index, sex, and race. CONCLUSIONS: Ultrasound echo intensity is a viable surrogate measure for tongue fat volume and may provide a convenient modality to characterize tongue fat in OSA.

Influence of apnea vs hypopnea predominance in predicting mean therapeutic positive airway pressures among patients with obstructive sleep apnea.

STUDY OBJECTIVES: Lower therapeutic positive airway pressure (PAP) levels are associated with improved response to non-PAP therapies in the treatment of obstructive sleep apnea. The aim of this study was to evaluate the prevailing notion that patients with apnea-predominant obstructive sleep apnea require higher therapeutic PAP levels compared to patients with hypopnea-predominant obstructive sleep apnea. METHODS: An institutional review board-approved retrospective review was performed using strict inclusion criteria: presence of type I or III sleep study, apnea-hypopnea index > 10 events/h, and adherence to auto-adjusting continuous positive airway pressure. Patients were stratified by apnea (> 50% apneas) or hypopnea (≤ 50% apneas) predominance, and PAP data were compared. Statistical analyses were performed using Student's t test and linear regression modeling. RESULTS: Between January 1, 2018 and January 1, 2020, 500 patients met inclusion criteria. Two hundred twenty-one (44.1%) patients were apnea-predominant and 279 (55.8%) were hypopnea-predominant. Apnea-predominant patients had a slightly greater mean PAP (9.01 vs 8.36, P = .002) than hypopnea-predominant patients. Univariable and multivariable linear regression of 7 variables (obstructive apnea percentage, age, sex, body mass index, apnea-hypopnea index, O2 nadir, mask type) showed obstructive apnea percentage was the weakest predictor of therapeutic PAP levels. CONCLUSIONS: Apnea-predominant individuals demonstrated a clinically insignificant difference in PAP level compared to hypopnea-predominant individuals; moreover, obstructive apnea percentage was not a strong predictor of therapeutic PAP levels. Of the modeled variables, the strongest predictor of PAP level was apnea-hypopnea index. Further studies are needed to explore these relationships as well as additional variables that may contribute to predicting therapeutic PAP levels. CITATION: Yu JL, Liu Y, Tangutur A, et al. Influence of apnea vs hypopnea predominance in predicting mean therapeutic positive airway pressures among patients with obstructive sleep apnea. J Clin Sleep Med. 2021;17(11):2171-2178.

Prospective Determination of Airway Response to Upper Airway Stimulation: A New Opportunity for Advanced Device Titration.

OBJECTIVES/HYPOTHESIS: Response to upper airway stimulation (UAS) is associated with the degree of airway opening during stimulation. UAS programming may affect this opening. The objective of this study was to examine airway changes in response to five different electrode configurations programmable within the Inspire UAS system. STUDY DESIGN: Prospective single-arm cohort study. METHODS: Subjects who underwent UAS implantation were recruited for a prospective single-arm cohort study during UAS device activation. Functional thresholds were recorded for all settings. Awake nasopharyngoscopy was performed to examine the retropalatal (RP) and retroglossal (RG) regions at rest and during activation with all settings at their functional thresholds. Cross-sectional measurements were made by two blinded reviewers and reported as percent change in airway size. RESULTS: Sixteen patients were included. The standard setting (+-+) resulted in the greatest change in RP area in 43.8% of patients. An alternative setting resulted in greatest change in 56.2% of patients (--- and o-o in 18.8% each, -o- in 12.5%, and -+- in 6.3% of patients). Average response to all five settings was utilized to classify degree of palatoglossal coupling. Most patients had some enlargement (20%-70% change in RP area, 43.8%) or no enlargement (<20% change, 43.8%), whereas a minority of patients (12.5%) had marked enlargement (>70% change). RP and RG expansion were not correlated. CONCLUSION: Degree of RP expansion varied among patients and settings. Although the standard setting resulted in greatest RP change in a plurality of patients, over half had a greater response to an alternative setting. Future studies should address whether choice of setting based on RP expansion results in improved outcomes. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:218-223, 2021.

Relation between arousability and outcome of upper airway stimulation in the Stimulation for Apnea Reduction (STAR) Trial.

STUDY OBJECTIVES: Upper airway stimulation (UAS) is an innovative surgical treatment for obstructive sleep apnea; however, the treatment failure rate is approximately 22%. Easy arousability may limit the tolerability of stimulation and, by extension, its effectiveness. The odds ratio product (ORP) is a continuous electroencephalographic metric of arousal propensity (range: 0 [deep sleep] to 2.5 [full wakefulness]), and its rate of decline after arousal (ORP-9) is a risk factor for susceptibility to arousal in the presence of frequent arousal stimuli. We hypothesized that individuals with deeper sleep (low average ORP and low ORP-9) are more likely to respond to UAS. METHODS: ORP and ORP-9 were calculated from 126 baseline polysomnograms of participants in the STAR Trial. These values were compared between responders and nonresponders. Adjusted linear modeling was performed to determine the association between ORP-derived variables and treatment response. RESULTS: No differences were found between responders and nonresponders in unadjusted comparisons of ORP-derived variables. On linear regression modeling, significant correlation was found between non-rapid eye movement ORP and reduction in apnea-hypopnea index (P = .004). CONCLUSIONS: No significant difference in ORP was noted between responders and nonresponders to UAS therapy; however, contrary to our initial hypothesis, linear regression modeling trended toward a positive relationship between ORP and UAS response, suggesting that those who have lighter sleep are more likely to respond to therapy; however, these results are only exploratory, and future larger prospective studies are needed to confirm this relationship. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Name: STAR Trial; Identifier: NCT01161420.

Utility of the modified Mallampati grade and Friedman tongue position in the assessment of obstructive sleep apnea.

STUDY OBJECTIVES: The modified Mallampati (MM) grade and Friedman tongue position (FTP) are commonly used scales that assess the oropharynx during evaluation for obstructive sleep apnea (OSA). Though used by many practitioners, there is controversy in the literature regarding their practical utility. The goal of this review will be to review the history of how the MM and FTP were developed, to discuss current evidence for their usefulness in the workup of OSA, and to provide future direction to better understand their utility in the workup of OSA. METHODS: We searched the literature (PubMed) for the terms "modified Mallampati" and "Friedman tongue position." Articles were selected based on our study objectives emphasizing articles discussing the utility of MM and FTP in managing OSA. CONCLUSIONS: MM and FTP have the potential to be useful assessment tools in the evaluation of OSA. When performing this examination, it is important for physicians and other medical providers to understand the pitfalls of the MM and FTP including the potential difficulty in performing the exam and the lack of consistency between examiners in both the terminology and execution of this physical exam finding. Better methods to standardize the assessment are necessary to ensure consistent evaluation among individual examiners while at the same time keeping the method simple and convenient for wide use as a clinical screening tool.

Upper airway stimulation therapy and sleep architecture in patients with obstructive sleep apnea.

OBJECTIVES/HYPOTHESIS: To quantify changes in sleep architecture before and after upper airway stimulation (UAS) therapy in patients with obstructive sleep apnea. STUDY DESIGN: Retrospective chart review. METHODS: This study was performed at a single-institution tertiary academic care center. Patients who responded successfully to UAS implantation were selected for this study. Preoperative and postoperative sleep studies were compared to determine sleep architecture changes. Primary outcomes included sleep architecture parameters such as N1, N2, N3, and rapid eye movement (REM) in addition to others. Secondary outcomes included body mass index. RESULTS: Thirty-five patients met inclusion criteria for this study. There was significant improvement across several sleep architecture parameters. N1 sleep percent decreased from 16.7% ± 2.1% preoperatively to 10.1% ± 1.6% postoperatively (P = .023). Time spent in N2 increased from 148.0 ± 12.4 minutes to 185.5 ± 10.4 minutes (P = .030), whereas N3 increased from 21.9 ± 5.0 minutes to 57.0 ± 11.1 minutes (P = .013). No significant changes were observed in REM sleep. Arousal index decreased from 38.8 ± 4.0 to 30.3 ± 4.0 (P = .050). CONCLUSIONS: There was significant improvement across several sleep architecture parameters among patients who responded successfully to UAS implantation. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:1085-1089, 2020.

Hypoglossal Nerve (Cranial Nerve XII) Stimulation.

Hypoglossal nerve stimulation is a novel strategy for the treatment of obstructive sleep apnea (OSA). Its anatomy allows for easy surgical access, and its function as a motor nerve allows for tolerable neurostimulation. It has shown success as a therapy for the treatment of OSA with a greater than 80% success rate. Patients who use the device not only show improvement in symptoms but also tolerate the device well with high rates of adherence to therapy as well as a high majority preferring it over continuous positive airway pressure therapy.

Updates on management of pediatric obstructive sleep apnea.

Obstructive sleep apnea (OSA) affects about 1%-5% of the pediatric population. The consequences of untreated OSA in children include neurocognitive deficits, behavioral problems, poor school performance as well as systemic and pulmonary hypertension. The treatment options for pediatric OSA are numerous with a variety of surgical and non-surgical interventions. As our understanding of the complexities of OSA grows, the options for management have continued to expand as well. The objectives of this review are to describe the commonly prescribed treatments for pediatric OSA including adenotonsillectomy as well as use of positive airway pressure. We also highlight other surgical and non-surgical interventions available. In addition, we provide updates on current research focusing on newer diagnostic and experimental treatment modalities.

Transoral robotic surgery versus upper airway stimulation in select obstructive sleep apnea patients.

OBJECTIVES: Transoral robotic surgery (TORS) has been used to treat obstructive sleep apnea (OSA) since 2009, with recent meta-analysis showing an average reduction of apnea-hypopnea index (AHI) from 44.3 to 17.0. In 2014, upper airway stimulation surgery (UAS) was approved for OSA treatment, with results showing an average AHI reduction from 32.0 to 15.3. Given there was a period when TORS was available and UAS was not, we looked at a subset of patients treated with TORS but who could have qualified for UAS and compared their outcomes to patients who received UAS. METHODS: This is a retrospective chart review comparing TORS to UAS in treatment of OSA performed by a single surgeon between 2011 and 2016. Inclusion criteria were a body mass index less than 35 and AHI between 20 and 65 consistent with criteria for UAS implantation. Patients who received TORS and met the inclusion criteria had their preoperative drug-induced sleep endoscopy recordings re-evaluated. Patients with anteroposterior retropalatal collapse that would have qualified them for UAS had their outcomes compared to patients who received UAS. RESULTS: Results between TORS and UAS showed an average AHI reduction of 12.7 and 33.3, respectively. Overall cure rate, defined as AHI < 5, was 10.0% and 70.3%, respectively. CONCLUSION: Results of this study indicate that, when met with criteria for both TORS and UAS, patients receiving UAS had greater improvement in several objective measures of OSA. Studies like this may help direct future treatment algorithms for surgical management of OSA. LEVEL OF EVIDENCE: 4 Laryngoscope, 129:256-258, 2019.

Postnasal drip and postnasal drip-related cough.

PURPOSE OF REVIEW: This article describes the pathophysiology and management of postnasal drip (PND) with and without cough. RECENT FINDINGS: PND is a common complaint in primary care and ear-nose-throat offices, and is often, but not always, associated with chronic cough. Because it lacks objective testing and its symptoms can be vague and variable, PND has become a catch-all diagnosis for a variety of nasal and throat-related symptoms. Studies have shown that the traditional pathophysiology of PND related to sinonasal disease does not clearly lead to chronic cough and that the cough from PND may be related to an airway sensory hypersensitivity rather than actual irritation from inflamed nasal secretions. SUMMARY: The article summarizes the current recommendations on evaluation and management of PND as well as brings to discussion new therapies and hypothesis regarding its pathophysiology.

Frontal sinus volume predicts incidence of brain contusion in patients with head trauma.

BACKGROUND: The function of the paranasal sinuses is a topic of debate. One hypothesis suggested has been that sinuses act as a "crumple zone," serving to protect the contents of the head from impact. In this study, we examine the interactions of the frontal sinus and the brain in the setting of head trauma. Our formal hypothesis is that frontal sinus volume is less in head trauma patients with contusion than in head trauma patients without contusion. METHODS: Computed tomographic (CT) scans of patients who sustained blunt head trauma performed at the University of Pittsburgh Medical Center from 2007 to 2012 were reviewed retrospectively. Inclusion criteria were presence of blunt trauma and complete brain and maxillofacial CT scan. Exclusion criteria included patients with incomplete imaging, imaging unrelated to trauma, previous cranial injury, and penetrating trauma.With the use of maxillofacial CT scans, height, depth, and width were measured, and a cubical approximation of volume was determined for each frontal sinus. Presence of frontal sinus fracture was considered an indicator of high-impact trauma. Grading of brain contusion severity was performed using head CT scans. A scale of 0 to 5 was used based on the Marshall Criteria.Categorical data were analyzed using the χ(2) or Fisher's exact test. Continuous data were analyzed using Student's t test or analysis of variance. p < 0.05 was considered statistically significant. RESULTS: Among patients with frontal sinus fracture, the average sinus volume of those without contusion was 32.72 mL, while the average sinus volume of those with brain contusion was 21.85 mL (p = 0.023). Thus, the volume of the frontal sinuses was 33% less in patients with contusion than in patients without contusion. CONCLUSION: Our study supports the theory that the frontal sinuses impart a protective advantage against frontal brain contusion. The dynamics of head injury and force distribution during trauma may be the basis for more advanced protective devices. LEVEL OF EVIDENCE: Prognostic study, level III.