Positional Obstructive Sleep Apnea Research Articles

Comparing the Characteristics of REM and Positional Obstructive Sleep Apnea Phenotypes Among Jordanian Population

Comparing the Characteristics of REM and Positional Obstructive Sleep Apnea Phenotypes Among Jordanian Population

Upper airway morphology in adults with positional obstructive sleep apnea

PurposeTo compare the anatomical balance and shape of the upper airway in the supine position between adults with positional obstructive sleep apnea (POSA) and adults with non-positional OSA (NPOSA).MethodsAdults diagnosed with OSA (apnea-hypopnea index (AHI) > 10 events/h) were assessed for eligibility. POSA was defined as the supine AHI more than twice the AHI in non-supine positions; otherwise, patients were classified as NPOSA. Cone beam computed tomography (CBCT) imaging was performed for every participant while awake in the supine position. The anatomical balance was calculated as the ratio of the tongue size to the maxillomandibular enclosure size. The upper airway shape was calculated as the ratio of the anteroposterior dimension to the lateral dimension at the location of the minimal cross-sectional area of the upper airway (CSAmin-shape).ResultsOf 47 participants (28 males, median age [interquartile range] 56 [46 to 63] years, median AHI 27.8 [15.0 to 33.8]), 34 participants were classified as having POSA (72%). The POSA group tended to have a higher proportion of males and a lower AHI than the NPOSA group (P = 0.07 and 0.07, respectively). After controlling for both sex and AHI, the anatomical balance and CSAmin-shape were not significantly different between both groups (P = 0.18 and 0.73, respectively).ConclusionAdults with POSA and adults with NPOSA have similar anatomical balance and shape of their upper airway in the supine position.Trial registrationThis study was registered with the Australian New Zealand Clinical Trials Registry (ANZCTR Trial ACTRN12611000409976).

Efficacy of vibrotactile positional therapy devices on patients with positional obstructive sleep apnoea: a systematic review and meta-analysis

IntroductionVibrotactile positional therapy (PT) devices are a new treatment modality for positional obstructive sleep apnoea (POSA). This review aimed to determine the effect of vibrotactile PT on the Apnoea Hypopnoea...

Positional obstructive sleep apnea (POSA)

Positional obstructive sleep apnea (POSA)

Patient compliance and satisfaction with a new forehead device for positional obstructive sleep apnoea treatment: a post hoc analysis of a randomised controlled trial

BackgroundThe influence of body position in obstructive sleep apnoea patients is well known. A positional therapy device placed at the forehead has proven to be effective in reducing the severity...

0793 Effect of Sleeping Position on Obstructive sleep apnea in Children Undergoing Polysomnography

Abstract Introduction Obstructive sleep apnea (OSA) in children is characterized by partial or complete upper airway obstruction during sleep, associated with gas exchange abnormalities and disrupted sleep with well-recognized neurobehavioral, neurocognitive, cardiovascular consequences. Positional obstructive sleep apnea (POSA) is defined as a lower AHI (by 50%) in the non-supine position than in the supine position. POSA has been well described in adults, affecting about 55% of adults with OSA. This occurs because airway collapse is maximal in the supine position compared to lateral or prone positions in this subset of patients with significant reduction in airway dimension occurring antero-posteriorly compared to circumferential reduction in airway dimension. However, POSA has not been well studied in children. Methods In this single center retrospective study, data was collected from one hundred consecutive polysomnographic studies from children (6-18 years) with moderate and severe OSA. Mean age was 10.7 years with 50% males in our cohort. Regression analysis was performed to study the relationship of sleeping position with the following variables: Age, sex, BMI, neck circumference, AHI, and desaturation index (DI) in supine and non-supine positions. Results 60% of the patients in our study had significantly lower (by 50%) AHI and DI in non-supine position. This effect was seen in both moderate and severe OSA, though the effect was higher with increasing AHI and BMI. The effect of sleeping position persisted even when corrected for time spent in each position. Conclusion Most of the children in our cohort showed significant reduction in OSA in non-supine sleeping position. Positional therapy (PT), being a low-cost and non-invasive intervention is a reasonable approach in patients who demonstrate differences in AHI, oxygenation, and ventilation. Identifying the OSA phenotype and the subset of OSA patients likely to benefit from non-supine position increases the success of PT. PT may be helpful in situations where adenotonsillectomy may not be indicated and CPAP may not be well tolerated, not desired by the patient, and/or not sufficient to improve OSA. We intend to perform further analysis to study the effect of position on gas exchange and identify the phenotype who may benefit from PT in a larger cohort. Support (if any)

Older Age is Associated With Positional Obstructive Sleep Apnea

ObjectivesUntreated obstructive sleep apnea (OSA) is associated with cognitive dysfunction; however studies report low adherence rates to standard continuous positive airway pressure (CPAP) treatment in the elderly. Positional OSA (p-OSA) is a subset that can be cured by positional therapy of avoiding supine sleep. However, there is no well-established criteria to identify patients who could benefit from positional therapy as an alternative or adjunct to CPAP. This study investigates if older age is related to p-OSA using different diagnostic criteria. DesignCross-sectional study. ParticipantsParticipants aged 18 years old or more who underwent polysomnography for clinical reasons at University of Iowa Hospitals and Clinics over a 1-year period from July 2011 to June 2012 were enrolled retrospectively. MeasurementP-OSA was defined as a high supine-position dependency of obstructive breathing events with potential resolution of OSA in nonsupine positions [high apnea-hypopnea index on supine positions (s-AHI)/ AHI on nonsupine positions (ns0AHI) combined with ns-AHI < 5/hour]. Different cutoff points (2, 3, 5, 10, 15, 20) were applied to determine a meaningful ratio of supine-position dependency of obstructions [s-AHI/ns-AHI]. We compared the proportion of patients with p-OSA between the older age group (≥65 years old) and the propensity score (PS)-matched (upto 1:4) younger age group (<65 years old) using logistic regression analyses. ResultsIn total, 346 participants were included. The older age group had a higher s-AHI/ns-AHI ratio than the younger age group (mean 31.6 [SD 66.2] versus 9.3 [SD 17.4], median 7.3 [interquartile range [IQR], 3.0-29.6) versus 4.1 (IQR, 1.9-8.7). After PS-matching, the older age group (n = 44) had higher proportion of those with a high s-AHI/ns-AHI ratio and ns-AHI< 5/hour compared with the younger age group (n = 164). (s-AHI/ns-AHI≥10: 54.6% versus 31.7%, OR 2.44 (95% CI, 1.22–4.90); s-AHI/ns-AHI≥15: 47.7% versus 26.2%, OR 2.24 (95% CI, 1.14–4.37); s-AHI/ns-AHI≥20: 40.9% versus 19.5%, OR 2.52 (95% CI, 1.22–5.20)) ConclusionOlder patients with OSA are more likely to have severe position dependent OSA, that is potentially more treatable with positional therapy. Thus, clinicians treating older, cognitively impaired geriatric patients unable to tolerate CPAP therapy should consider positional therapy as an adjunct or alternative.

Predictors of uvulopalatopharyngoplasty outcomes in patients with supine predominant positional obstructive sleep apnea: a prospective observational study

Background It is uncertain which factors substantially influence outcomes after uvulopalatopharyngoplasty (UPPP) in patients with supine predominant obstructive sleep apnea (POSA) Objective To explore the predictors of UPPP outcomes in POSA patients. Methods A total of 108 patient(52 positional patients (POSA) and 56 nonpositional patients(NPP)), who underwent the revised uvulopalatopharyngoplasty (H-UPPP), were retrospectively studied. The pre-operative information of these patients, including polysomnography (PSG), and upper airway CT, were collected for analysis. Results No difference was found in surgical success rates between POSA and NPP undergoing H-UPPP. In POSA patients, there were statistically significant differences between responders and nonresponders in body mass index (BMI), preoperative supine AHI, time of SaO2 < 90% (TS90) (all p < .05), minimal anteroposterior airway (mAP) (p = .016), minimal lateral airway (mLAT) (p = .002), minimal cross-sectional airway area (mCSA) (p < .001) at the velopharynx. mLAT (p = .014) and mCSA (p = .002) at the glossopharynx. The independent associated factors for surgical success were lower BMI (p < .001), narrowerm LAT (p = .002) and mAP (p < .001) at velopharynx, and wider mCSA (p < .001) at glossopharynx in POSA. Conclusion POSA patients with lower BMI, narrower mLAT and mAP at velopharynx, wider mCSA at glossopharynx were more likely to achieve a positive outcome with H-UPPP.

Comparing the diagnostic value of the positional obstructive sleep apnea definitions

Several definitions were proposed to diagnose Positional Obstructive Sleep Apnea (pOSA). However, the comparison between these definitions according to their diagnostic value is scarce in the literature. Thus, we decided to conduct this study to compare between the four criteria according to their diagnostic value. Between 2016 and 2022, 1092 sleep studies were performed at the sleep lab at the Jordan University Hospital. Patients who had an AHI <5 were excluded. pOSA was described according to the four definitions; Amsterdam Positional OSA Classification (APOC), supine AHI twice the non-supine AHI (Cartwright), Cartwright plus the non-supine AHI <5 (Mador), and overall AHI severity at least 1.4 times the non-supine severity (Overall/NS-AHI). Furthermore, 1033 polysomnographic sleep studies were retrospectively analyzed. The prevalence of pOSA according to the reference rule was 49.9% among our sample. The Overall/Non-Supine definition had the highest sensitivity, specificity, positive predictive value, and negative predictive value, which were 83.5%, 99.81%, 99.77%, and 85.88% respectively. The Overall/Non-Supine definition also had the highest accuracy among the four definitions (91.68%). Our study showed that all the criteria had a diagnostic accuracy above 50%, indicating that they were accurate in forming the diagnosis of pOSA. The Overall/Non-Supine criteria had the highest sensitivity, specificity, diagnostic odds ratio, and positive likelihood ratio as well as the lowest negative likelihood ratio, indicating the superiority of this criterion over the other definitions. Choosing the right criteria for diagnosing pOSA would result in fewer patients being assigned to CPAP and more being assigned to positional therapy methods.

Power spectral analysis of the sleep electroencephalogram in positional obstructive sleep apnea

Objective/BackgroundPrevious studies have shown that obstructive sleep apnoea (OSA) is associated with reduced delta EEG and increased beta EEG power and increased EEG slowing ratio. There are however no studies that explore differences in sleep EEG between positional obstructive sleep apnoea (pOSA) and non-positional obstructive sleep apnoea (non-pOSA) patients. Patients/methods556 of 1036 consecutive patients (246 of 556 were female) undertaking polysomnography (PSG) for the suspicion of OSA met the inclusion criteria for this study. We calculated power spectra of each sleep epoch using Welch's method with ten, 4-s overlapping windows. Outcome measures such as Epworth Sleepiness Scale, SF-36 Quality of Life, Functional Outcomes of Sleep Questionnaire and Pyschomotor Vigilance Task were compared between the groups. ResultsPatients with pOSA had greater delta EEG power in NREM and greater N3 proportions compared to their non-pOSA counterparts. There were no differences in theta (4–8Hz), alpha (8–12Hz), sigma (12–15Hz) or beta (15–25Hz) EEG power or EEG slowing ratio between the two groups. There were also no differences in the outcome measures between these two groups. The division of pOSA into spOSA and siOSA groups showed better sleep parameters in siOSA but with no difference in sleep power spectra. ConclusionsThis study partially supports our hypothesis in showing that pOSA, compared to non-pOSA, is associated with increased delta EEG power but did not show any variation to beta EEG power or EEG slowing ratio. This limited improvement in sleep quality did not translate to measurable changes to outcomes, suggesting beta EEG power or EEG slowing ratio may be key factors.

Positional Obstructive Sleep Apnea is Strongly Associated with Older Age

Positional Obstructive Sleep Apnea is Strongly Associated with Older Age

The Prevalence of Positional Obstructive Sleep Apnoea in a Sample of the Saudi Population

PurposePositional obstructive sleep apnoea (POSA) is of important clinical significance, as positional treatment can augment or obviate continuous positive airway pressure. This study aimed to determine the prevalence of POSA and its characteristics using different definitions.MethodsWe retrospectively examined a cohort of patients who underwent polysomnography (PSG) between 2013 and 2019 at two sleep centres. Demographic data and PSG data were collected from 624 patients with an apnoea–hypopnea index (AHI) ≥ 5. POSA was defined using different criteria as follows: (1) AHI of at least twice as high in the supine position as in the lateral position (Cartwright’ s definition). (2) A supine AHI ≥ 10 and a lateral AHI < 10 (Marklun’s definition). (3) AHI of at least twice as high in the supine position than in the lateral position, with the lateral AHI not exceeding 5 (Mador’s definition or Exclusive POSA; e-POSA). (4) AHI ≥ 15/h; a supine AHI ≥ twice that of the nonsupine AHI ≥ 20 min of sleep in the supine and nonsupine positions; and a nonsupine AHI < 15 (Bignold’s definition).ResultsThe prevalence of POSA was 54% (Cartwright), 38.6% (Mador), 33.8% (Marklund) and 8.3% (Bignold). Multivariate regression analysis showed a body mass index (BMI) < 35 kg/m2 was the only significant predictor of POSA. Mador’s definition had the highest diagnostic yield (sensitivity 63%; specificity 100%; area under the receiver operating characteristic curve 90.2%).ConclusionPOSA is common, but its prevalence depends on the definition used. Low BMI was identified as a significant predictor.

Clinical management of a severe case of positional obstructive sleep apnea syndrome

Clinical management of a severe case of positional obstructive sleep apnea syndrome

Effects of the combination of novel eye mask sleep position therapy device and oral appliance on positional OSA: A multi-arm, parallel-group randomized controlled trial

ObjectivesWe explored whether a new combination of eye mask sleep position therapy (SPT) and oral appliance therapy (OAT) was more effective at treating positional obstructive sleep apnea (POSA) than was the use of either device alone. MethodsIn this randomized controlled trial, 60 POSA subjects diagnosed by standard polysomnography (PSG) were divided into three groups (ratio 1:1:1): SPT, OAT, and SPT combined with OAT (SOT). Participants underwent hospital-based follow-ups during months 1 and 6 after beginning treatment. The primary outcome was the decline in the apnea hypopnea index (AHI) at month 6. The secondary outcomes were changes in oxygen-derived parameters and the curative effect at month 6. ResultsAfter 6 months of treatment, PSG showed that SPT, OAT, and SOT all improved the AHI and oxygen-derived parameters. The AHI decline was significantly better in the SOT group than in the OAT or SPT group (71.58% [50.56–84.84%] for SOT, 44.42% [21.23–67.52%] for OAT, and 33.24% [19.03–54.62%] for SPT at 6 months) (P = 0.018 and P < 0.001 for the comparisons of SOT with OAT and SOT with SPT, respectively). In terms of oxygen-derived parameters, only the sleep apnea-specific hypoxic burden (SASHB) improved more in the SOT group (76.89% [57.43–85.91%]) than in the other groups (44.73% [32.38–72.69%] for OAT and 41.82% [15.40–65.24%] for SPT, P = 0.002 and P < 0.001 for the comparisons of SOT with OAT and SOT with SPT, respectively). The efficacies of SPT, OAT, and SOT were 36.84%, 50%, and 80% at 6 months; the SOT group evidenced the highest value (rate ratio [95% confidence interval] 1.78 (1.05–3.03), P = 0.048 and 2.17 (1.16–4.07), P = 0.010, for the comparisons of SOT with OAT and SOT with SPT, respectively). ConclusionThe combination of SPT and OAT was better than either treatment alone and may represent a good option for the treatment of POSA. Trial registrationChinese Clinical Trial Registry; URL: http://www.chictr.org.cn/showproj.aspx?proj=42,852; No. ChiCTR1900025584.

Characteristics of patients with positional OSA according to ethnicity and the identification of a novel phenotype-lateral positional patients: a Multi-Ethnic Study of Atherosclerosis (MESA) study.

We investigated the characteristics of obstructive sleep apnea (OSA) positional patients' (PP) phenotypes among different ethnic groups in the Multi-Ethnic Study of Atherosclerosis (MESA) dataset. Moreover, we hypothesized the existence of a new OSA PP phenotype we coined "Lateral PP," for whom the lateral apnea-hypopnea index is at least double the supine apnea-hypopnea index. From 2,273 adults with sleep information, we analyzed data of 1,323 participants who slept more than 4 hours and had at least 30 minutes of sleep in both the supine and the nonsupine positions. Demographics and clinical information were compared for the different PP and ethnic groups. 861 (65.1%) patients had OSA, and 35 (4.1%) were Lateral PP. Lateral PP patients were mainly females (62.9%), obese (median body mass index: 31.4 kg/m2), had mild-moderate OSA (94.3%), and mostly were non-Chinese American (97.1%). Among all patients with OSA, 550 (63.9%) were Supine PP and 17.7% were supine-isolated OSA. Supine PP and Lateral PP were present in 73.1% and 1.0% of Chinese Americans, 61.0% and 3.4% of Hispanics, 68.3% and 4.7% of White/Caucasian, and 56.2% and 5.2% of Black/African-American patients with OSA. Chinese Americans have the highest prevalence of Supine PP, whereas Black/African-American patients lean toward less Supine PP and higher Lateral PP. Lateral PP appears to be a novel OSA phenotype. However, Lateral PP was observed in a small group of patients with OSA and thus its existence should be further validated. Ben Sason Y, Oksenberg A, Sobel JA, Behar JA. Characteristics of patients with positional OSA according to ethnicity and the identification of a novel phenotype-lateral positional patients: a Multi-Ethnic Study of Atherosclerosis (MESA) study. J Clin Sleep Med. 2023;19(3):529-538.

The Effects of Barbed Repositioning Pharyngoplasty in Positional and Non-Positional OSA Patients: A Retrospective Analysis.

The aim of our retrospective study is evaluating the effectiveness of barbed repositioning pharyngoplasty (BRP) in a consecutive cohort of patients and assessing its impact on positional indexes in order to potentially identify specific obstructive sleep apnea (OSA) phenotypes for patients who might benefit more significantly from this intervention. A single-center retrospective study with baseline and follow-up type III sleep tests evaluating the Apnea Hypopnea Index (AHI), supine AHI, non-supine AHI, oxygen desaturation index (ODI), mean SaO2, percentage of time spent at SaO2 below 90% (CT90), and lowest oxygen saturation (LOS) were performed. The patients were then divided into groups according to Sher's criteria and Amsterdam Positional OSA Classification (APOC). Parametric and non-parametric tests and univariate and multivariate analyses were conducted. The study finally included 47 patients. The statistical analysis showed significant improvement in AHI, supine AHI, non-supine AHI, and ODI after surgery. The linear regression showed that high values of baseline AHI, AHI supine, and AHI non supine predict more significant postoperative reductions in AHI, AHI supine, and AHI non supine, respectively. Therapeutic success was achieved in 22 patients out of 47. The logistic regression did not find any independent risk factors for success. The most significant reduction in AHI, supine AHI, and non-supine AHI was observed in the APOC 3 group while the APOC 1 patients experience a substantially lower improvement. BRP appears to be an effective surgical procedure for the treatment of OSA. The non-positional patients might benefit more from BRP in comparison with positional patients. Moreover, OSA severity should not be considered an absolute contra-indication for this surgical procedure.

Oral Appliances for Severe Positional Obstructive Sleep Apnea Syndrome: A Case Report

Severe positional obstructive sleep apnea syndrome (POSAS) is a common clinical respiratory disorder with an incidence of 26.7% to 74.5%. Continuous positive airway pressure (CPAP) combined with positional therapy is the gold standard of treatment. However, a mandibular advancement device (MAD) is an effective alternative to CPAP when compliance with CPAP is low or if CPAP is rejected by the patient. A 63-year-old Caucasian male (BMI 26.1 kg/m2) complaining of repeated episodes of daytime sleepiness and heavy snoring was diagnosed with POSAS and treated with a MAD. After two years, polysomnographic (PSG) control analysis showed a significant reduction in the number of obstructive sleep apnea/hypopnea episodes per hour (AHI) by 58.9% in the lateral position and 75.5% in the supine position, complete remission of symptoms, a significant reduction in the severity of POSAS, and an overall improvement in quality of life. No adverse events or reduction in compliance were observed during the follow-up period. For severe POSAS, MADs may be an alternative method that is well tolerated by patients and has a good safety profile.

Residual OSA in Down syndrome: does body position matter?

To examine children with Down syndrome with residual obstructive sleep apnea (OSA) to determine if they are more likely to have positional OSA. A retrospective chart review of children with Down syndrome who underwent adenotonsillectomy at a single tertiary children's hospital was conducted. Children with Down syndrome who had a postoperative polysomnogram with obstructive apnea-hypopnea index (OAHI) > 1 event/h, following adenotonsillectomy with at least 60 minutes of total sleep time were included. Patients were categorized as mixed sleep (presence of ≥ 30 minutes of both nonsupine and supine sleep), nonsupine sleep, and supine sleep. Positional OSA was defined as an overall OAHI > 1 event/h and a supine OAHI to nonsupine OAHI ratio of ≥ 2. Group differences are tested via Kruskal-Wallis test for continuous variables and Fisher's exact tests for categorical. There were 165 children with Down syndrome who met inclusion criteria, of which 130 individuals had mixed sleep. Patients who predominately slept supine had a greater OAHI than mixed and nonsupine sleep (P = .002). Sixty (46%) of the mixed-sleep individuals had positional OSA, of which 29 (48%) had moderate/severe OSA. Sleeping off their backs converted 14 (48%) of these 29 children from moderate/severe OSA to mild OSA. Sleep physicians and otolaryngologists should be cognizant that the OAHI may be an underestimate if it does not include supine sleep. Positional therapy is a potential treatment option for children with residual OSA following adenotonsillectomy and warrants further investigation. Lackey TG, Tholen K, Pickett K, Friedman N. Residual OSA in Down syndrome: does body position matter? J Clin Sleep Med. 2023;19(1):171-177.

Analysis of Lateral Decubitus Position During Sleep in Patients With Obstructive Sleep Apnea Using WatchPAT Device

Background and Objectives: Measurement of sleep parameters in both supine and non-supine positions is important for the diagnosis of positional obstructive sleep apnea (OSA). However, the influence of right and left lateral decubitus positions (RLDP and LLDP, respectively) on sleep parameters is relatively unknown and has not been well investigated. This study was performed to verify the associations between sleep parameters and lateral decubitus sleep position.Methods: A retrospective study was performed on 38 patients who were diagnosed with OSA and underwent surgical interventions from January 2014 to December 2016. Preoperative sleep parameters were evaluated with WatchPAT, and patients who slept sufficiently in both RLDP and LLDP to accurately analyze sleep parameters were enrolled in the study. Basic clinical data including body mass index (BMI) and nasal endoscopic findings of patients were assessed.Results: The difference in peripheral arterial tonometry apnea-hypopnea index (pAHI) and PAT respiratory disturbance index (pRDI) between RLDP and LLDP showed no association with the side of deviated nasal septum. Patients with higher BMI showed higher pRDI in LLDP than RLDP (p=0.038). The difference in sleep position percentage between RLDP and LLDP was negatively correlated with the difference in pRDI (p=0.023).Conclusion: Higher BMI patients with OSA might benefit more from sleeping in RLDP than LLDP. Patients slept longer in the lateral decubitus position that produced lower pRDI. Not only supine and non-supine positions, but also RLDP and LLDP need to be evaluated in patients with OSA.

Subtypes of obstructive sleep apnea in children and related factors.

To investigate the prevalence of positional obstructive sleep apnea (P-OSA) and rapid eye movement-related OSA (REM-OSA) in children with OSA and identify related factors. This was a cross-sectional study among children aged 2-12 years diagnosed with OSA using overnight polysomnography (PSG) between August 1, 2020, and July 31, 2021. Demographics, anthropometrics, PSG, and OSA-18 questionnaire data were recorded. Data from a total of 474 children were available for analysis. Children had a median age of 4.8 (4.1, 6.4) years, 66.7% were male, and 23.2% were obese. The prevalence of P-OSA was 38.2% and that of REM-OSA was 43.0%. P-OSA was correlated with age and obstructive apnea-hypopnea index (OAHI; odds ratio [OR] = 1.172, 0.947; P = .005, < 0.001, respectively), but not sex, obesity, and adenoid and tonsil size (OR = 1.265, 0.785, 0.826, 0.989; P = .258, 0.327, 0.153, 0.905, respectively). REM-OSA was correlated with age, adenoid size, tonsil size, and OAHI (OR = 0.876, 1.320, 1.387, 1.021; P = .024, 0.040, 0.001, 0.042) but not with sex and obesity (OR = 0.910, 1.281; P = .643, 0.315). The prevalence of P-OSA was 38.2% and that of REM-OSA was 43.0% in children with OSA. Age was correlated with both the prevalence of P-OSA and REM-OSA, with an increasing and decreasing prevalence as children grew older, respectively. The severity of OSA was significantly associated with the prevalence of both P-OSA and REM-OSA. Adenoid and tonsil size were correlated with the prevalence of REM-OSA but not P-OSA. Obesity and sex were not associated with the prevalence of P-OSA or REM-OSA. Wu Y, Zheng L, Cui G, Xu Z, Ni X. Subtypes of obstructive sleep apnea in children and related factors. J Clin Sleep Med. 2022;18(10):2397-2404.