Supine AHI Research Articles

Clinical efficacy study of position-responding mandibular advancement device in patients with obstructive sleep apnea.

Although mandibular advancement device (MAD) treatment is effective in patients with obstructive sleep apnea (OSA), there are still some concerns about its potential therapeutic and side effects. Thus, we developed a novel MAD that auto-titrates depending on its position in patients with OSA. Therefore, we conducted a clinical trial to determine the efficacy of an auto-titrating mandibular advancement device (AMAD) for treating OSA. Fourteen patients with OSA were enrolled in this study. Polysomnography (PSG) was conducted at the start of the clinical trial, and PSG with AMAD in situ was performed after three months of treatment. The mean Epworth Sleepiness Scale (ESS) and STOP-Bang scores were 8.21 ± 4.21 and 5.00 ± 1.00, respectively. After 3 months of treating AMAD, STOP-Bang scores improved to 3.75 ± 1.06; however, there was no significant change in ESS scores. Additionally, we found statistically significant improvements in several respiratory parameters in the PSG data after AMAD treatment. The AHI (32.85 ± 21.71 to 12.93 ± 10.70), supine AHI (45.91 ± 23.58 to 15.59 ± 12.76), lateral AHI (13.94 ± 10.95 to .49 ± 7.40), lowest O2 saturation (79.71 ± 6.22 to 84.00 ± 5.71), total arousal number (191.14 ± 112.07 to 86.57 ± 48.80), and arousal index (33.76 ± 21.00 to 15.05 ± 8.42) were recorded. However, there were no significant changes in total sleep time, sleep efficiency, or mean oxygen saturation. Additionally, we did not observe any major side effects during treatment, specifically related to tooth or jaw pain. Our clinical trial revealed that AMAD improved PSG parameters and reduced the incidence of common side effects. Therefore, AMAD may be an effective alternative treatment for OSA.

Gender differences in obstructive sleep apnea syndrome: a pilot study

PurposeOSAS is a syndrome that often presents clinically differently between men and women. The aim of this study was to assess the clinical presentation, nocturnal home sleep cardiorespiratory monitoring and therapeutic adherence to CPAP in both sexes to identify the most frequent patterns.MethodsData from the first visit, the nocturnal home sleep cardiorespiratory monitoring and follow-up visit of 74 OSA patients were collected. Exclusion criteria included other respiratory and/or neuromuscular diseases (including Obesity hypoventilation syndrome) and other non-respiratory sleep disorders.ResultsMen were older and had a higher supine AHI and ODI compared to women. In addition, BMI and age correlated positively with AHI in males. Women had a higher hypopneas frequency and better therapeutic adherence to CPAP.ConclusionsMen were associated with a higher AHI when sleeping in the supine position and this may be useful to look for new therapeutic options in combination with or as an alternative to CPAP. BMI correlated positively with AHI in men and this should be considered to stimulate weight loss as the main treatment to reduce the number of apneas/hypopneas, as men also had less therapeutic adherence to CPAP in our study. Females presented a significantly higher frequency of hypopneas than men, as well as a lower number of desaturation events per hour (ODI): these differences in the nocturnal home sleep cardiorespiratory monitoring could reflect different pathophysiological mechanisms of OSAS onset between the two sexes, which should be investigated in future scientific studies.

Evaluating Positional Obstructive Sleep Apnea in Children: Prevalence, Characteristics, and Risk Factors.

This study investigates the prevalence, risk factors, and clinical characteristics of positional obstructive sleep apnea (POSA) among pediatric patients diagnosed with obstructive sleep apnea (OSA). A total of 1,236 children aged 0 to 17 years who underwent nocturnal polysomnography (PSG) and completed the Sleep Questionnaire were included. After excluding those with an AHI <1, neurological or muscular disorders, or insufficient sleep time in specific positions, 908 patients remained: 158 with POSA and 750 with non-positional OSA (NPOSA). Propensity score matching (PSM) was applied at a 1:2 ratio, resulting in a final sample of 153 POSA and 306 NPOSA patients. Data analyses were performed using R software (version 4.2.3). The prevalence of POSA was 12.8%. After PSM, patients with POSA had a lower overall AHI (8.66 vs 10.30), REM-AHI (14.30 vs 17.40), and NREM-AHI (7.43 vs 8.77) compared to those with NPOSA. POSA patients also had a shorter total sleep time (411 vs 427minutes), spent less time in the supine position (168 vs 225minutes), and more time in non-supine positions (241 vs 202minutes) than NPOSA patients. Additionally, while the supine AHI was higher in POSA patients (15.60 vs 10.30), the non-supine AHI was lower (5.00 vs 11.00) compared to NPOSA patients. The minimum oxygen saturation was slightly higher in POSA patients (0.88 vs 0.87). All differences were statistically significant (P < 0.05). Risk factors for POSA included mild OSA, allergic rhinitis, non-allergic rhinitis, and obesity. The prevalence of POSA in children is lower than in adults, and its severity is less than that of NPOSA. Compared to NPOSA patients, POSA patients had significantly higher AHI during supine sleep and lower AHI during non-supine sleep. POSA patients also spent more time in non-supine positions, suggesting that avoiding supine sleep may help reduce apnea events. These findings highlight the importance of monitoring and managing sleep posture in POSA patients.

Polysomnographic outcomes of revision adenoidectomy in children with obstructive sleep apnea and recurrent/residual adenoidal hypertrophy.

Recurrent/residual adenoidal hypertrophy after adenotonsillectomy in children can result in obstructive sleep apnea (OSA). We aimed to assess the polysomnographic (PSG) outcomes of revision adenoidectomy in children with recurrent/residual adenoidal hypertrophy and OSA. This was a single-center retrospective study that included children with sleep studies that confirmed OSA and known history of adenotonsillectomy who were diagnosed with adenoidal hypertrophy and subsequently underwent revision adenoidectomy. Pre- and postoperative PSG variables of revision adenoidectomy were included in the analysis. A total of 20 children were included in the study. The cohort included 13 males and 7 females with a mean age of 7.8 years (± 3.6 years). The mean BMI z score was 1.96 [1.31, 2.43]. The median duration from adenotonsillectomy performance was 2.3 years [1.4, 4.0]. Overall, revision adenoidectomy resulted in significant improvements in multiple respiratory parameters, including AHI 6.6 [1.4, 13. 7] vs 14.8 [7.4, 20.7], p = 0.02; oxygen desaturations nadir 88.0 [84.0, 93.0] vs 80.0 [72.2, 88.9], p = 0.01; supine AHI 8.6 [1.5, 14.3] vs 17.6 [8.3, 30.2], p = 0.02; and arousal index 12.2 [9.6, 15.7] vs 18.9 [13.4, 24.9], p = 0.04. Children with recurrent/residual adenoidal hypertrophy after adenotonsillectomy who undergo revision adenoidectomy experience improvements in respiratory event, gas exchange, and arousal index.

Abstract 12619: Positional Obstructive Sleep Apnea and Risk of Atrial Fibrillation

Introduction: Obstructive sleep apnea (OSA), a common sleep disorder, has been associated with the risk of atrial fibrillation (AF). OSA is a heterogenous condition but is heavily position-dependent. Positional OSA (POSA) is a common form of OSA in which OSA is predominantly manifested in a supine position. The implication of POSA in cardiovascular risks is unclear. This study aimed to examine whether the risk of AF is different between individuals with POSA and those with non-positional OSA (nPOSA). Methods: We identified individuals with OSA (AHI ≥ 5/h) from the Sleep Heart Health Study (SHHS) cohort. POSA was defined if overall AHI ≥ 5/h, supine AHI ≥ 5/h, and supine AHI greater than twice the non-supine AHI based on the SHHS visit 1 sleep study. Incident AF was deemed present if detected on a 12-lead ECG during the SHHS visit 2 or confirmed by the parent cohorts at any time between the baseline PSG and the final follow-up date for AF assessment. Multiple logistic regression analysis was conducted with covariates including age, race, gender, body mass index, smoking status, systolic blood pressure, use of hyperlipidemia medication, use of diabetes medication (oral or insulin), use of hypertension medication, cholesterol, triglyceride, and high-density-lipoprotein, and other sleep characteristics (total sleep duration, sleep efficiency, and sleep onset latency). Results: The study included a total of 1712 participants (females, 45%; mean age, 65 years old) with OSA. Compared with individuals with nPOSA, those with POSA were more likely to be white (p=.002), older (p&lt;.043), have lower AHI (p&lt;.001), lower BMI (p&lt;.001), lower systolic blood pressure (p&lt;.001), and lower triglyceride (p=.029), longer sleep duration (p=.002), and less likely to take hypertension medication (p&lt;.001). After accounting for these differences, the odds of incident AF were about 30% lower in the individuals with POSA compared with those with nPOSA (OR=0.7, p=.037). Conclusions: Individuals with OSA exhibit a lower risk of AF when they have POSA. While it is possible that residual confounding could account for this finding, we conclude that POSA might represent a unique phenotype with distinct cardiovascular implications.

Airway Collapsibility during Drug-Induced Sleep Endoscopy Relates with Clinical Features of Obstructive Sleep Apnea.

Increased pharyngeal collapsibility leads to obstructive sleep apnea (OSA). Positive airway pressure titration during drug-induced sleep endoscopy (DISE-PAP) provides objective collapsibility metrics, the pharyngeal opening pressure (PhOP), and active pharyngeal critical pressure (PcritA ). We examined the interrelationships between risk factors of OSA, airway collapsibility measures, and clinical manifestations of the disease. This is a cross-sectional analysis of consecutive OSA patients undergoing DISE-PAP. Nasal PAP was increased stepwise until inspiratory flow limitation was abolished, signifying PhOP. PcritA was derived from the resulting titration pressure-flow relationships. Clinical data including demographics, anthropometrics, sleep studies, and patient-symptom questionnaires were obtained from the electronic medical record. Multivariate regression was used to evaluate the relationship between risk factors, airway collapsibility, and clinical data. On average, the 164 patients meeting inclusion criteria were middle-aged (54.2 ± 14.7 years), overweight/obese (BMI 29.9 ± 4.5 kg/m2 ), male (72.6%), White (79.3%) and had severe OSA (AHI 32.0 ± 20.5 events/hour). Mean PhOP was 7.5 ± 3.3 cm H2 O and mean PcritA was 0.80 ± 3.70 cm H2 O. Younger age (Standardized β = -0.191, p = 0.015) and higher BMI (Standardized β = 0.176, p = 0.028) were associated with higher PhOP, but not PcritA . PhOP and PcritA were both associated with AHI, supine AHI, and SpO2 nadir. Higher PhOP was associated with higher snoring scores (Standardized β = 0.246, p = 0.008), but not other patient-reported outcomes. Objective assessment of passive and active airway mechanics during DISE relates with clinical risk factors for OSA. Quantitative measures of collapsibility provide accessible and meaningful data, enhancing the standard sleep surgery evaluation. 4 Laryngoscope, 134:1978-1985, 2024.

The effect of head of bed elevation on upper airway collapsibility during drug-induced sleep endoscopy.

Drug-induced sleep endoscopy with positive airway pressure evaluates the collapsibility of the upper airway. It is currently unknown whether body position affects this assessment. We sought to determine whether the collapsibility of the airway may change with head of bed elevation. A prospective, consecutive cohort study was performed by 2 sleep surgeons at a tertiary care center. Inclusion criteria included adults 18 years of age and older with obstructive sleep apnea who were intolerant to continuous positive airway pressure therapy. Patients underwent drug-induced sleep endoscopy with positive airway pressure to evaluate them for alternative treatment options. Patients were evaluated in supine position with the head of bed both level and elevated to 30°. The airway was evaluated using the standardized VOTE scoring system in both positions. The 61 patients included in the study were predominantly male (70.5%), middle-aged (51.2 years), and obese (body mass index, 30.2 kg/m2) with moderate-to-severe obstructive sleep apnea (apnea-hypopnea index, 34.1 events/h). The cohort consisted of predominantly positional obstructive sleep apnea (mean supine apnea-hypopnea index 48.7 events/h, nonsupine apnea-hypopnea index 20.8 events/h). All 4 sites of the upper airway demonstrated a significant decrease in airway opening pressures with the head of bed elevated compared to level (P < .01 for all sites). There was no significant difference in VOTE scoring between level and upright positions. Patients with the head of bed elevated to 30° have a significantly lower degree of airway collapsibility compared to patients in the level position but no significant change in VOTE scoring was observed. Owen GS, Talati VM, Zhang Y, LoSavio PS, Hutz MJ. The effect of head of bed elevation on upper airway collapsibility during drug-induced sleep endoscopy. J Clin Sleep Med. 2024;20(1):93-99.

1002 Bilateral Nonarteritic Anterior Ischemic Optic Neuropathy (NAION) in a Patient with Obstructive Sleep Apnea (OSA)

Abstract Introduction Nonarteritic Anterior Ischemic Optic Neuropathy (NAION) is an ischemic insult to the anterior portion of the optic nerve with unclear etiology. Several small sized studies and case reports have demonstrated association between OSA and NAION. In this case, we present a patient with bilateral NAION who was later diagnosed with OSA which may signify this important clinical association. Report of case(s) A 57-year-old man with history of hypertension, presented to the ophthalmology clinic for sudden painless decreased visual acuity of the right eye for one-month duration. He had no history of head trauma or other neurological deficits on his initial presentation. He reported having “bad vision” in his left eye for the entire of his life. Funduscopic evaluation revealed bilateral optic disc edema more in the left eye. Laboratory workup including CBC, CMP and HbA1C were within normal limits. Brain MRI showed only mild nonspecific scattered subcortical and deep periventricular hyperintensities suggestive of chronic small vessel ischemic disease and no acute infarct or masses. MRI of the orbits was normal. A diagnosis of bilateral Nonarteritic Anterior Ischemic Optic Neuropathy (NAION) was highly suggested based on the clinical history and examination findings. A referral to a sleep clinic was made to evaluate for possible sleep apnea. A polysomnogram confirmed obstructive sleep apnea with AHI of 7.2/h, REM AHI of 7.7/h and supine AHI 14.9/h. Nocturnal hypoxemia associated with the respiratory events with time of O2 saturation &amp;lt; 88% for 29 minutes. Patient was referred for a titration study to determine the appropriate PAP pressure to treat his sleep disordered breathing. Conclusion This case adds to the current evolving evidence of the link between OSA with NAION. It signifies the importance of having an index of suspicion, among both sleep specialists and ophthalmologists, to recognize patients who may have one of the conditions and consider screening for the other, which may lead to earlier diagnosis and improved outcomes. Support (if any)

0548 Position-dependent obstructive sleep apnea and the cardiovascular risks

Abstract Introduction Position dependent obstructive sleep apnea (PdOSA) is highly prevalent, but the implication of PdOSA in cardiovascular (CV) outcomes has not been studied. We hypothesized that PdOSA is associated with lower risk of future CV events than those without PdOSA. Methods We included patients who underwent diagnostic polysomnography (PSG) at a single academic center. The study included patients with ≥2 hours of total sleep time, 30 minutes in both supine and non-supine sleep, and OSA (apnea hypopnea index [AHI]≥5/hr). We defined PdOSA as either POSA (overall AHI≥5/hr accompanied by supine AHI (sAHI) at least twice as high as non-supine AHI (ns-AHI)), or ePOSA (POSA criteria + ns-AHI &amp;lt; 5/hr (i.e., normalized)). Blood pressure (BP) was derived by averaging multiple measures of clinic BP within 1 year of PSG. All patients were followed up to 11 years to identify incident CV events (including acute coronary syndrome, stroke, and new heart failure). We examined the association of PdOSA with CV events with a logistic regression, adjusting for age, sex, race, BMI, systolic BP, and OSA severity (mild [AHI 5-15] vs. moderate to severe [≥15]). Results A total of 1750 patients (mean age: 54 years, female 60%) were included. POSA and ePOSA were present in 47% and 23% of the cohort. Patients with either POSA or ePOSA were less obese and had less severe OSA compared with those without POSA and ePOSA. Patients with ePOSA had lower BP (systolic BP 128.8 vs 131.2 mmHg, p=0.003) than those without ePOSA. Over a median 8.3 years of follow-up, a total of 340 CV events occurred. In multivariable analysis, both POSA and ePOSA were associated with lower odds of future CV events (OR 0.8, 95% CI [0.64-0.99], p=0.044; OR 0.69 [0.52-0.89], p=0.0061, respectively). Analysis stratified by OSA severity showed that the ePOSA association was present only in those with mild OSA (OR 0.67 [0.48-0.94], p=0.021). Conclusion Among patients with OSA, PdOSA is associated with more favorable CV outcomes than those without PdOSA. The benefit appears to be limited to those with mild OSA. Future studies should compare the CV risks between PdOSA patients and those without OSA. Support (if any)

0902 Comparative Analysis of Sleep Apnea Patients Selected from the Stroke Unit vs Outpatient Clinic

Abstract Introduction To our knowledge, there have been studies actively looking for patients with suspected SA in the Stroke Unit (SU), but most of them were conducted using a portable polysomnography (PSG), and no study has performed Level 1 PSG (L1PSG) to date. We conducted L1PSG to the acute stroke patients selected in the SU, and conducted L1PSG to patients who visited the Neurology Outpatient Clinic (NOC) with subjective SA symptoms at the same time. By comparison, we tried to find out the SA characteristics of acute stroke patients. Methods This study was conducted on patients admitted to SU from April 1, 2021 to October 31, 2022, and patients who visited NOC during the same period and underwent L1PSG. Among patients admitted to the SU, trained night shift nurses selected patients with SA symptoms with a modified mallampati score of 3 or higher. Cases under intracranial pressure control or other interventions were excluded. Outpatients were enrolled in patients who underwent L1PSG by visiting the NOC to examine only SA. The results of the pre-sleep questionnaire and L1PSG were compared. Results Of a total of 829 stroke patients admitted to SU, 31 SU patients received L1PSG, and during the same period, 74 patients received L1PSG for SA testing at NOC. The average age of SU and NOC was 56 and 57 years, and the median BMI was 26.9 and 26.4. In the survey, the ISI (7 vs 12, p=0.04) and PSQI (5 vs 7, p=0.021) scores were statistically significantly higher in NOC patients. As a result of the L1PSG, AHI (38.8 vs 23.1, p=0.027), AHI in Supine (59.3 vs 25.6, p=0.004) and NonREM AHI (36.3 vs 20.9, p=0.027) were statistically significantly higher in SU patients. Conclusion Patients screened SA at SU overlooked their symptom and thought their sleep quality was better than that of NOC patients, but the actual AHI was higher. In particular, acute stroke patients show a large difference in AHI in supine compared to NOC, so lateral position can be recommended when absolute bed rest is needed in situations where SA is suspected in SU. More follow-up studies will be needed. Support (if any)

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.

O059 A study in Physiological Activation Responses to Posture Shifts in Sleep and The Impact of Supine Avoidance Alarms

Abstract Introduction This study assessed the frequency and duration of arousal responses associated with posture shifts during sleep and the time taken to resume sleep following posture shifts with versus without a supine-avoidance alarm. Method Sleep and posture shift outcomes during a baseline in-home sleep study (Embletta MPR plus an inactive supine-avoidance alarm device) and subsequent sleep study after 6-8 weeks of supine-avoidance treatment were examined in 66 patients with supine-predominant OSA. A technician blinded to supine-treatment data scored each sleep study, including arousal responses (3-15 and ≥15-sec EEG changes). All posture shifts lasting &amp;gt;5 sec were identified from sleep study and supine-alarm device posture recordings. All sustained (≥30 sec) posture shifts commencing from established sleep during baseline and supine-avoidance nights were assessed for arousal responses (within -30 to +3 sec of each posture shift) and the time taken to resume sleep following each posture shift. Results The study population was 62.1% males with a mean±SD age 52.8±11.9 years, BMI 31.9.4±7.8 kg/m², AHI 18.0±9.9 /hr (supine AHI=40.2±38.8 /h). From a total of 418 (baseline) vs 283 (supine-avoidance) sustained posture shifts (median [IQR] 6[3-10] vs 6[3-9] per patient), the majority [342/418 vs 244/283; 91[75-100] vs 100[84-100]%) were associated with an arousal, followed by 0.5 [0.0 to 1.0] min before sleep resumed, with no difference with versus without the supine-alarm. Conclusion Posture shifts from sleep are mostly associated with brief arousal prior to any supine-avoidance alarm, after which a supine avoidance alarm effectively discourages supine positioning with minimal disturbance to the resumption of sleep.

Sex-Related Differences in Polygraphic Parameters in a Population of Patients with Obstructive Sleep Apnea Syndrome.

Sex-related differences in the prevalence and clinical presentation of Obstructive Sleep Apnea Syndrome (OSAS) have been widely documented. The aim of this study was to investigate the influence of patients' sex on polygraphic parameters with particular attention to sleep autonomic changes in a population of OSAS patients. Sixty OSAS patients aged 55-65 years (30 men, 30 women) were enrolled. Sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI) and daytime sleepiness with the Epworth Sleepiness Scale (ESS). The presence of respiratory events and autonomic changes during the night was investigated by polygraphy. Similar main cardiovascular risk factors prevalence was observed in both men and women. We observed a significant difference in PSQI (higher in women, p=0.0001) and ESS (higher in men, p=0.004) scores. Snoring (p=0.033), supine AHI (p=0.004), T90 (p=0.021), LO2 (p=0.0001), LF/HF ratio and LF (p=0.0001) were significantly higher in men. Sex differences in PSQI mean score and LF/HF ratio variability were preserved in all the subgroups of OSA severity. The influence of sex in modulating cardiovascular risk is a widely discussed topic. In our study, men showed more severe polygraphic parameters and an increase in LF/HF ratio compared to women. The results of our investigation suggest the relevance of delivering information about the different expressions of OSAS in men and women in order to improve diagnostic skills and in-depth prevention approaches.

Clinical Characteristics and Surgical Outcomes of Obstructive Sleep Apnea Patients With Mixed Apnea Components.

This study was aimed to investigate clinical implications of mixed apnea (MA) in patients with obstructive sleep apnea (OSA), particularly whether surgical outcomes differ between OSA patients with and without MA events. Retrospective cohort study. Single tertiary medical center. Eighty-eight patients with OSA who underwent multilevel upper airway surgery were included. Patients were divided into 2 groups according to the presence of MA events: "pure group" (n = 30) and "mixed group" (n = 58). The clinical characteristics and surgical outcomes were compared between the 2 groups. The mixed group included more males (P = .020) and hypertensive patients (P = .009) and had a higher apnea-hypopnea index (AHI; P < .001) than the pure group. The surgical success rate was lower in the mixed group (29.3%) than in the pure group (73.3%; P < .001). Furthermore, the postoperative improvements in total AHI (P < .001), supine AHI (P < .001), and oxygen desaturation index (P = .006) were lower in the mixed group than in the pure group. Logistic regression analysis confirmed that the presence of MA (P = .002) was an independent predictor of poor surgical outcomes in patients with OSA. OSA patients with MA showed different clinical features and poor surgical outcomes compared to those without MA. These results imply that OSA with MA components may have a distinct pathophysiology, and the presence of MA should be considered in the surgical treatment of OSA.

0544 Polysomnography characteristics of children with obesity: A single center retrospective study

Abstract Introduction The constellations of symptoms known as obstructive sleep apnea (OSA) results from either partial or complete airway obstruction during sleep. This affects effective gas exchange and disrupts sleep architecture resulting in sleep fragmentation with downstream immediate and long-term adverse effects. Obesity is a significant risk factor in childhood OSA, especially in post-pubertal children. Obese/overweight children have been found to have significantly higher rates of OSA than their normal-weight counterparts, independent of tonsillar size. Polysomnography characteristics (PSG) comparing children with obesity with and without comorbidities (Hypertension, Diabetes or Pre-diabetes) has not been previously described. Methods Retrospective analysis of 190 obese children (BMI&amp;gt;95th centile), age between 7-18 years with AHI ≥5/hour met the criteria for the data analysis. Clinical, demographic and PSG parameters of children with obesity with and without co-morbidities were compared using Wilcoxon rank sum test. Correlation (Spearman non-parametric) and regression model was employed to explore associations between demographic and PSG characteristics. Results Majority of the obese children (mean BMI 33.2) had mild OSA, with no significant difference in AHI between the two groups. Children with obesity and comorbidities were older with higher BMI. There was no difference in BMI between the two groups after adjusting for BMI z scores. AHI increased with increasing BMI centiles. In our regression model, peak ETCO2 was associated with Black race, AHI, rhinitis and inversely associated with asthma. Peak ETCO2 increased with BMI. Oxygen at baseline, nadir and desaturation duration inversely correlated with BMI-centiles. Older children had lower O2 nadir. Black race was associated with higher desaturation, supine AHI, and arousal index. Supine AHI was higher with rhinitis. Average heart rate when awake, NREM and REM increased with higher BMI. Conclusion In our study, majority of the children had mild OSA with no significant difference in AHI between obese children with and without comorbidities. AHI, average heart rate and peak ETCO2 increased with BMI. O2 nadir was lower in older children and with higher BMI. Black race was associated with higher peak ETCO2, higher desaturation and supine AHI. Children with obesity and comorbidities were older with higher BMI suggesting synergistic effect of BMI and duration of obesity. Support (If Any)

0706 Older Age Is a Strong Risk Factor for Supine-position Dependent Obstructive Sleep Apnea

Abstract Introduction Positional obstructive sleep apnea (p-OSA) is commonly defined as a supine-position dependent OSA with the ratio of apnea hypopnea index while supine (s-AHI) to AHI while non-supine (ns-AHI) being greater than 2. Prevalence of p-OSA amongst OSA patients varies from 20 to 75% depending on the study. Previous studies using this definition showed p-OSA being more likely to be in subjects with lower BMI, smaller neck circumference, and milder OSA compared to patients with non-positional OSA (np-OSA). The primary aim of this study is to assess the prevalence of p-OSA using different cutoffs of s-AHI/ ns-AHI ratio and to evaluate the correlation of p-OSA with age, gender, neck circumference (NC), and medical comorbidities of OSA. Methods 846 participants aged 18 year or older who underwent diagnostic polysomnography at an academic sleep disorders center from July 2011 to June 2012 were recruited for this study. Inclusion criteria were total sleep time greater than 120 minutes, diagnosis of OSA, sleep time in supine position more than 10 minutes, and sleep time in non-supine position more than 10 minutes. We tested supine position dependency using the ratio of supine AHI to non-supine AHI (s-AHI/ns-AHI) and classified the subjects into p-OSA and np-OSA based on the ratio of s-AHI/ns-AHI at 2, 3, 5, and 10 respectively to assess the prevalence of p-OSA using each cut-off. For the multivariable logistic analysis of p-OSA and its association with independent variables, s-AHI/ns-AHI of 10 and ns-AHI of being less than 5 was used to define p-OSA. Multivariate analysis was conducted to explore correlation with age, gender, neck circumference, and OSA comorbidities (COPD, hypertension, diabetes). Age of 60 was used to define older age group. Results Of 356 eligible participants, p-OSA was highly prevalent when conventional s-AHI/ns-AHI ration of 2 was used resulting in p-OSA in 274 subjects (prevalence of 77%). The mean value of s-AHI/ns-AHI in this aggregate group of all 356 subjects was 11.7 (much higher than conventional ratio of 2). Thus, using s-AHI/ns-AHI ratio of 10 as the cut-off for supine-position dependency, 114 subjects were classified to have p-OSA. Logarithmic multivariate analysis demonstrated that there was a statistically significant, correlation between age and s-AHI/ns-AHI after adjusting for gender, NC, diabetes, hypertension, and COPD (p-value &amp;lt; 0.05). In the older group, 44.3% of older patient had s-AHI/ns-AHI &amp;gt; 10 compared to 30% of young patients (p-value &amp;lt; 0.05). 41.8% of the older group met criteria for p-OSA compared to 29.2% of younger group (p-value &amp;lt; 0.05). Being of older age was strong risk factor for p-OSA with odds ratio (OR) of 1.76 (confidence interval 1.01 – 3.09; p&amp;lt; 0.05). This effect of age on p-OSA was further modified by gender and diabetes. Older men had significantly higher OR of 3.23 (CI 1.51-6.89) for p-OSA whereas olde women was with OR of 0.79 (CI 0.33-2.42). Older persons with diabetes showed significantly higher OR than non-diabetic older persons (OR of 6.81 [CI 1.7-26.8] vs OR 1.22 [CI 0.65-2.29] respectively). Conclusion Supine-position dependency of obstructive events is much stronger than the conventional ratio of two. Thus, stricter definition is positional OSA is desired for more clinically meaningful use of this subgroup of OSA. Using stricter definition with higher supine-position dependency, an older age is significantly associated with positional OSA, especially in men or in diabetic patients. Support (If Any)

The outcome of oral appliance therapy on position-dependent obstructive sleep apnea: A multicenter randomized controlled trial

<h3>Introduction</h3> This multicenter trial on patients with obstructive sleep apnea (OSA) treated with an oral appliance aimed to determine the effect of sleeping positions. <h3>Methods</h3> A cohort of 314 patients with OSA were enrolled and evaluated at 8 weeks and 1 year, focusing on treatment effects. At baseline and the 2 follow-ups, new polygraphic registration comparing the proportion of treatment responders without position-dependent OSA (non–position-dependent OSA [non-POSA]) and with POSA was used. <h3>Results</h3> At the 8-week and 1-year follow-up, 205 and 139 patients were included, respectively. The proportion of responders (apnea-hypopnea index [AHI] <10 and/or ≥50% reduction in AHI) was 56% for the non-POSA group and 69% for the POSA group (not significant [NS]). The responders increased at the 1-year follow-up: 68% and 77% for the non-POSA and POSA groups (NS), respectively. The absolute change in AHI in all sleeping positions at 8 weeks was –12.9 (interquartile range, –25.0 to –0.5) in the non-POSA group and –10.5 (interquartile range, –19.9 to –5.3; NS) in the POSA group. However, the decrease in supine AHI was significantly greater among subjects with POSA. In contrast, the decrease in nonsupine AHI was significantly greater in the non-POSA group, an effect that remained at the 1-year follow-up. <h3>Conclusions</h3> Our hypothesis that subjects with POSA at baseline would have a higher treatment response rate after oral appliance treatment compared with subjects without POSA was rejected. However, those with POSA had a significantly higher supine AHI decrease, and those without POSA had significantly less nonsupine AHI.

Proportion of rapid eye movement sleep related obstructive sleep apnea (REM related OSA) in patients with sleep disordered breathing: A cross sectional study.

Background and Objectives:Obstructive sleep apnea (OSA) during rapid eye movement (REM) stage of sleep is gaining importance in recent years. This study was done to determine the proportion of REM-related OSA and its associated polysomnographic features.Methods:One hundred forty-two patients were included in the study. REM-related OSA was defined based on previously established broad and strict criteria (REM apnea–hypopnea index [AHI]/non-REM [NREM] AHI ratio ≥2 and REM AHI >5 with NREM AHI <5, respectively), and its association with polysomnographic features was studied using appropriate statistical tools.Results:The proportion of REM-related OSA in the study was 56.3% and 25.3% as per broad and strict criterion, respectively. The REM-related OSA group had a mean younger age (47.4 ± 13.2 years) as compared to NREM-related OSA group (52.6 ± 15.8 years). Females (34 out of 45; 75.6%) were more likely to have REM-related OSA as compared to males (46 out of 107; 47.4%). Supine AHI, arousal index, oxygen desaturation index, length of the longest event, and the lowest oxygen saturation recorded during sleep had a significant association with REM-related OSA. 74% of patients with overall AHI <5 and 87% patients with overall AHI 5 to 15 satisfied the criteria for REM-related OSA as per broad criterion.Conclusion:REM-related OSA was quite prevalent in the study population (56.3%) and was more common in the mild and moderate severity subgroups of OSA.

Supine or non-supine apnea; which can be treated better with expansion sphincter pharyngoplasty?

ObjectivesExpansion sphincter pharyngoplasty is a well-known palatal correction surgery applied for obstructive sleep apnea patients. Even though high success rates are reported, in some patients, the desired outcome cannot be achieved. Therefore, patient selection is crucial to avoid undesirable outcomes. In this study we present our results with expansion sphincter pharyngoplasty, and we aim to show the difference between supine and non-supine apnea in terms of their response to the surgery, in order to utilize position dependency for selection of surgical candidates. MethodsPre- and post-operative polysomnography results of patients who underwent expansion sphincter pharyngoplasty were analyzed retrospectively. Total AHI, supine AHI, non-supine AHI, supine/non-supine AHI ratio and surgical success values are compared. Results85 patients were included to the study. Mean AHI significantly decreased from 48.7 ± 27.99 to 26.37 ± 21.16 with the surgery. Surgical success rate was found to be 51.8%. Both supine and non-supine apnea decreased significantly with the surgery, but the decrease was significantly higher in non-supine apnea (20.6% to 39.1% respectively, p = 0.016). There was significant negative correlation between pre-operative supine to non-supine AHI ratio and the change in AHI, showing that supine dominant patients had less improvement with the surgery (r = 0.274, p = 0.01). ConclusionExpansion sphincter pharyngoplasty is an effective surgery which achieves significant improvement in AHI. Non-supine respiratory events respond better to the surgery than supine events.