Oxygen Desaturation Index Research Articles

Oxygen Desaturation Index in Patients of OSA: Correlation with Sleepiness and Hypertension

Oxygen Desaturation Index in Patients of OSA: Correlation with Sleepiness and Hypertension

Effect of an Overnight Stay at 2500 m on Nocturnal Hypoxemia and Sleep-disordered Breathing in Patients with Pulmonary Vascular Disease: A Randomized Trial.

Patients with pulmonary vascular disease (PVD) often reveal nocturnal hypoxemia and sleep apnea. We investigated whether exposure to high altitude worsens those conditions. In a randomized-controlled crossover trial, stable patients with pulmonary arterial hypertension (PAH) or chronic thromboembolic pulmonary hypertension (CTEPH) without resting hypoxemia (PaO2 >8 kPa at low altitude) underwent respiratory polygraphy at 470 m and during an overnight stay at 2500 m. Patients with severe hypoxemia (SpO2 <80 % for >30 min) at 2500 m received supplemental oxygen therapy (SOT) according to safety criteria. Main outcomes were the number of patients who did not require SOT, the effect of high altitude on nocturnal SpO2, oxygen desaturation index (ODI, ΔSpO2 of ≥3 %), apnea-hypopnea index (AHI) and the effect of SOT. Of 27 patients (44 % women, 20/7 PAH/CTEPH, mean ± SD age 62 ± 14 y), 10 (37 %) required SOT during the course of the night (p=0.008 vs. low altitude). At 2500 m vs. 470 m, mean nocturnal SpO2 on ambient air decreased from 91 ± 2 % to 83 ± 4 % (mean change [95 %CI], -8 % [-9 to -6], p <0.001), time with SpO2 <90 % increased from 29 ± 27 % to 92 ± 15 % (+63 % [30 to 92], p <0.001), the ODI increased from 17 ± 14 /h to 42 ± 26 /h (+24.8 /h [12.8 to 36.5], p <0.001) but AHI remained unchanged. With SOT SpO2 was restored to values at 470 m. In stable, low-risk patients with PVD, altitude worsened nocturnal hypoxemia but not sleep-disordered breathing. The majority of patients did not require SOT according to predefined safety criteria. When needed, SOT restored low altitude indices of oxygenation. Clinical Trial registration available at www. gov NCT05089487.

Obstructive sleep Apnoea in patients with knee osteoarthritis before total knee arthroplasty and its impact on post-operative recovery of blood oxygen concentrations.

Post-operative delays in blood oxygen recovery are sometimes observed after total knee arthroplasty (TKA), with obstructive sleep apnoea (OSA) being a contributing factor. This study aimed to examine the prevalence of OSA and its correlation with post-operative oxygen saturation (SpO2) recovery in patients undergoing TKA for knee osteoarthritis (OA). This was an observational case-control study including patients with knee OA who underwent TKA between January 2018 and October 2021. Pre-operative symptoms of OSA were assessed, and the apnoea-hypopnoea index, 3% oxygen desaturation index (ODI), average SpO2 and sleep body positions were measured using sleep testing devices. Knee function was evaluated using the 2011 Knee Society Score and range of motion (ROM). A total of 240 patients (41 males and 199 females) with a mean age of 74 years (range 51-93 years) were included in this study. Of the 240 patients, 49 (20.4%) had no OSA, 104 (43.3%) had mild OSA and 87 (36.3%) had moderate to severe OSA. OSA severity increased with a higher body mass index. Diabetes prevalence increased as the severity of OSA increased. OSA severity did not affect pre-operative knee function scores or ROM. However, higher ODI and lower pre-operative SpO2 were associated with increased OSA severity. Additionally, patients with severe OSA exhibited a greater proportion of supine sleep time and delayed post-operative oxygen discontinuation. Patients with knee OA scheduled for TKA have a high prevalence of OSA. Increased OSA severity delay oxygen discontinuation after TKA.

Differential sleep architecture in different subtypes of positional obstructive sleep apnea in children.

Differential sleep architecture in different subtypes of positional obstructive sleep apnea in children.

Detection and Severity Classification of Sleep Apnea Using Continuous Wearable SpO2 Signals: A Multi-Scale Feature Approach

The use of wearable devices for sleep apnea detection is growing, but their limited signal resolution poses challenges for accurate diagnosis. This study explores the feasibility of using SpO2 signals from wearable sensors for detecting sleep apnea and classifying its severity. We propose a novel multi-scale feature engineering approach, which extracts features from coarsely grained SpO2 signals across timescales ranging from 1 s to 600 s. Our results show that traditional SpO2 markers, such as the oxygen desaturation index (ODI) and Lempel–Zip complexity, lose their relevance with the Apnea–Hypopnea Index (AHI) at longer timescales. In contrast, non-linear features like complex entropy, sample entropy, and fuzzy entropy maintain strong correlations with AHI, even at the coarsest timescales (up to 600 s), making them well suited for low-resolution data. Multi-scale feature extraction improves model performance across various machine learning algorithms by alleviating model bias, particularly with the Bayes and CatBoost models. These findings highlight the potential of multi-scale feature engineering for wearable device applications where only low-resolution data are commonly available. This could improve accessibility to low-cost, at-home sleep apnea screening, reducing reliance on expensive and labor-intensive polysomnography. Moreover, it would allow even healthy individuals to proactively monitor their sleep health at home, facilitating the early identification of potential sleep problems.

Preservation Palatopharyngoplasty for Obstructive Sleep Apnea With High Modified Mallampati Scores: Clinical and Polysomnographic Outcomes.

This study aims to describe and evaluate clinical and polysomnographic outcomes of the preservation palatopharyngoplasty procedure, which preserves pharyngeal mucosa and muscles, in patients with obstructive sleep apnea with high modified Mallampati scores (3 or 4). A retrospective chart review. A tertiary medical center. A total of 23 patients who underwent preservation palatopharyngoplasty between November 2022 and May 2024 were included. Outcomes measured were apnea-hypopnea index (AHI), oxygen desaturation index (ODI), Epworth Sleepiness Scale (ESS) scores, and Nasal Obstruction Symptom Evaluation (NOSE) Scale scores pre- and postsurgery. Data were analyzed using unpaired or paired t-tests, and statistical significance was set at P < .05. The mean age of included patients was 51.74 years. Postoperative results showed a significant 25.48% (standard deviation [SD] = 32.59) decrease in AHI (P = .0011) and 35.25% (SD = 11.00) mean decrease in ODI (P = .0030). REM sleep percentage increased from 12.96% to 21.35% (P = .0106), and REM AHI decreased from 55.49 to 40.02 events/h (P = .0255). Significant improvements were also seen in ESS (P = .0123) and NOSE scores (P = .0134). Among the included patients, 12 out of 23 patients achieved surgical success per Sher's criteria. The preservation palatopharyngoplasty significantly improved subjective and objective measures in OSA patients with higher Mallampati scores by enhancing upper airway patency and reducing OSA severity.

Evaluation of sleep position shifts in patients with obstructive sleep apnea syndrome with the use of a mandibular advancement device.

The aim of this study was to evaluate position shifts during sleep of patients with obstructive sleep apnea (OSA) syndrome both with and without the use of a mandibular advancement device (MAD). In total, 73 adult Caucasian patients diagnosed with obstructive sleep apnea syndrome confirmed by polysomnography were retrospectively enrolled. Inclusion criteria were as follows: age >20 years, body mass index <34 kg/m2, polysomnographic diagnosis of OSA, non-smoker, absence of comorbidities at diagnosis, and treatment with a MAD. Two polysomnographic monitoring were performed: one at the time of diagnosis (T0) and another after 3 months of treatment (T1). The parameters evaluated were the apnea-hypopnea index, oxygen desaturation index, the total number of position shifts, and position shift index (number of shifts per hour). Since the variables failed the normality test, the Wilcoxon test was performed to analyze the correlation between the mean of polysomnographic parameters at T0 and T1. The difference between the T1 and T0 values for each variable was evaluated using Spearman's rho correlation test. Statistical significance was set at p < 0.05. All the parameters, including respiratory and positional measures, were significantly reduced after the use of a MAD compared to the beginning. Spearman's correlation test revealed a relationship between the total number of sleep position shifts and the sleep position shift index with the oxygen desaturation index. However, no significant correlation was observed between the apnea-hypopnea index and the positional values.

Respiratory acclimatization and psychomotor performance after rapid ascent and during 3 weeks at 3,100 m-A prospective cohort study in healthy individuals.

Acclimatization to high altitudes over several weeks has not been extensively studied. Repeated physiological assessments were performed in healthy lowlanders staying at 3,100 m for 3 weeks. We hypothesized that acute exposure to 3,100 m results in hypoxemia, sleep-disordered breathing, and postural instability, while a 3-week acclimatization at 3,100 m will improve these outcomes. Sixteen healthy volunteers (23-33 years) underwent nocturnal pulse oximetry and nasal airflow monitoring during 1 night in Bishkek (760 m), and during nights 1, 8 and 22 at Too-Ashu (3,100 m), Kyrgyzstan. On each day after monitoring, reaction time [psychomotor vigilance test reaction time test, (PVT)] and postural control [center of gravity path length on balance board (COPL)] were assessed. Compared to 760 m, mean nocturnal SpO2 dropped in the first night at 3,100 m from mean ± SD 94.8% ± 1.9% to 86.3% ± 2.9% and recovered partially to 89.8% ± 1.5% after 3 weeks (P < 0.05 both comparisons to 760 m). Corresponding median (quartiles) oxygen desaturation indices were 1.0/h (0.3; 2.2), 6.5/h (4.5; 12.1) and 6.4/h (4.2; 11.1) time in bed (P < 0.05 both comparisons to 760 m). Median (quartiles) reaction times were 226 ms (212; 231), 236 ms (210; 259) and 228 ms (212; 246), P = NS, all comparisons. COPL worsened from 25.1 ± 4.1cm to 27.1 ± 4.1 cm (P < 0.05) and 26.4 ± 3.7 cm (P = NS compared to 760 m). In healthy lowlanders staying at 3,100 m, nocturnal SpO2 increased over 3 weeks after an initial drop but did not reach baseline values. Postural control was impaired in the first week of acute exposure to high altitude despite improvements in hypoxemia. Altitude exposure did not affect reaction time. Thus, acute and prolonged exposure to hypobaric hypoxia has differential effects on oxygenation, control of breathing, postural control, and reaction time.

Handheld blue light three-dimensional (3D) scanner versus lateral cephalometry for facial morphology assessment in obstructive sleep apnoea participants : Handheld blue light three-dimensional (3D) scanner for facial morphology assessment of obstructive sleep apnoea participants.

The main purpose of this study is to evaluate the facial morphology of obstructive sleep apnoea (OSA) individuals by using a handheld blue light three-dimensional (3D) scanner (HBL-3DS) in comparison to conventional lateral cephalometric radiography (LCR). Moreover, our research question is to explores the correlation between 3D facial and neck measurements with OSA indices, encompassing the hypoxic burden. This prospective cross-sectional study included forty-four adults with OSA. We compared three measurements between LCR and HBL-3DS images: modified facial profile angle (MFPA), nasolabial angle (NLA), and mandibular length (ML). Additionally, the 3D images of thirty-four participants with OSA indices were analysed for seventeen parameters, such as angles, ratios, and linear distances. This study revealed significant strong correlations (p < 0.001) between LCR and HBL-3DS in the measurements of MFPA (r = 0.675), NLA (r = 0.723), and ML (r = 0.675). However, no significant correlation was found between all predictors and the Apnoea-Hypopnea Index (AHI) or Oxygen Desaturation Index (ODI) in the 3D images of the thirty-four participants. Multivariate regression analysis demonstrated an independent negative correlation between mandibular width (MW) and nadir oxygen levels, while an independent positive correlation was observed between inner canthal width and the Rapid-Eye-Movement percentage (REM). The study highlighted a significant association between LCR and HBL-3DS. HBL-3DS delivers precise 3D facial and neck measurements, presenting itself as a potentially cost-effective, radiation-free, and portable screening method for participants with OSA in clinical settings.

The expression changes endothelial and fibrinolytic biomarkers in acute ischemic stroke patients with OSA

ObjectiveTo assess the expression changes of serum fibrinogen, E-selectin, and tissue-type plasminogen activator (t-PA) in acute ischemic stroke (AIS) patients with varying degrees of obstructive sleep apnea syndrome (OSA), and evaluate their value in diagnosing AIS with OSA.MethodsData were gathered from 80 patients with AIS who were admitted to the First Hospital of Jilin University between January 2023 and December 2023. Out of these, 60 patients completed the NIHSS Scale, ESS Scale, STOP-Bang Scale, and underwent polysomnography within a week of symptom onset. Based on the apnea-hypopnea index (AHI) score, patients were categorized into three groups: 15 in the non-exposed group (AHI < 5), 15 in the mildly exposed group (5 ≤ AHI ≤ 15), and 30 in the moderately to severely exposed group (AHI > 15). Serum levels of fibrinogen, E-selectin, and t-PA were determined using enzyme-linked immunosorbent assay.ResultsPolysomnography results indicated AIS with OSA had an increased arousal index and oxygen desaturation index (P < 0.001). Additionally, serum levels of fibrinogen, E-selectin, and t-PA were markedly elevated in the moderately-severely exposed group compared to the non-exposed group (P < 0.001), and these levels positively correlated with the severity of OSA. ROC curves showed the sensitivities of serum of fibrinogen, E-selection, and t-PA was 84.4%, 80%, and 82.2%, respectively, and the specificities of 60%, 66.7%, and 66.7%, compared with that of PSG respectively.ConclusionThe expression of serum fibrinogen, E-selectin, and t-PA is elevated in AIS with OSA and correlates with the severity of OSA.

Polysomnography Differences Between Sleepy and Non-Sleepy Obstructive Sleep Apnea (OSA) Patients

Background/Objectives: Factors underlying excessive daytime sleepiness (EDS) in obstructive sleep apnea (OSA) are not fully understood. We investigated whether polysomnography (PSG) parameters differed between non-sleepy and sleepy (based on the Epworth Sleepiness Scale (ESS)) OSA patients with the same disease severity, which may play a role in the presence of EDS. Methods: A total of 1307 patients, without cardiovascular, metabolic, respiratory, or inflammatory comorbidities, diagnosed with OSA (apnea–hypopnea index (AHI) ≥ 5 per hour of sleep) with type 1 PSG were included. Based on the AHI, patients were classified into mild- (AHI 5–14.9, n = 236), moderate- (AHI 15–29.9, n = 367), and severe-OSA (AHI ≥ 30, n = 704) groups. These groups were further divided into two subgroups based on the ESS, the most convenient and widely used tool to assess excessive daytime sleepiness: sleepy (ESS &gt; 10) and non-sleepy (ESS ≤ 10). PSG data were compared between groups, and multivariable logistic regression was used to identify differences after adjustment for confounders. Results: For the entire population, male sex, younger age, obesity, depression, increased wakefulness after sleep onset (WASO), the arousal index, shorter sleep latency, and all indices of OSA severity (AHI, oxygen desaturation index, mean and lowest resting room air pulse oximetry (SpO2), and sleep time with oxygen saturation &lt; 90% (TST90)) were significantly associated with EDS. The arousal index consistently showed a strong association with EDS across all OSA severity groups. Moderate-OSA sleepy patients were younger, with shorter sleep latency and increased indices of OSA severity, excluding the AHI. Severe-OSA sleepy patients were younger, males, and obese; had depression, decreased slow-wave sleep (SWS) and sleep latency, and increased WASO; and presented an increase in all indices of OSA severity. Conclusions: Our results suggest that male sex, younger age, obesity, the presence of depression, WASO, lower sleep efficiency, the arousal index, and all indices of OSA severity may account for the presence or absence of EDS in OSA patients and could be useful for exploring the underlying pathophysiological mechanisms for precision medicine.

Cardiovascular effects after five nights without continuous positive airway pressure for obstructive sleep apnea: a randomized controlled trial.

Although continuous positive airway pressure (CPAP) effectively prevents sleep apnea and reduces blood pressure, many patients do not use CPAP every night. This trial investigates cardiovascular effects after sleeping five nights without CPAP. We randomized 100 patients (67 men and 33 women with a mean age 64 ± 9 years) using CPAP treatment for moderate-to-severe sleep apnea to either withdraw treatment for five nights (n = 50) or to continue with CPAP (n = 50). The primary outcomes were arterial stiffness and 24 h blood pressure. The 24 h SBP increased by a mean of 2.8 mmHg [95% confidence interval (CI) 0.2-5.4 mmHg] (P = 0.035) and DBP increased by a mean of 1.7 mmHg (95% CI 0.1-3.3 mmHg) (P = 0.032) in the group without CPAP compared to the CPAP group. There was a significant effect on blood pressure in women but not in men. In women, SBP increased by 5.1 mmHg (95% CI 1.0-9.5 mmHg) (P = 0.017) and DBP by 2.9 mmHg (95% CI 0.4-5.6 mmHg) (P = 0.029). Arterial stiffness remained unaffected. Secondary outcomes that worsened in patients without CPAP included apnea-hypopnea index, oxygen desaturation index, hemoglobin levels, and daytime sleepiness. Blood pressure is affected after five nights of CPAP interruption, along with a rapid return of sleep apneas, nocturnal hypoxic events, daytime sleepiness and increased hemoglobin levels, but arterial stiffness was not affected. Blood pressure was affected in women only, suggesting a sex-related CPAP effect on blood pressure.

The differences between the subtypes of obstructive sleep apnea among different provinces in Turkey: a multicenter study.

Our aim in this study is to investigate the significance and implications of different clinical subtypes of patients with obstructive sleep apnea syndrome (OSAS) in three different sleep centers from varied provinces. Between January 2023 and November 2024, 330 patients from three sleep centers (Adana, Gaziantep, and Istanbul) were retrospectively examined for age, gender, body mass index (BMI), polysomnography parameters, sleep stages, arousals, oxygen parameters, heart rates, apnea-hypopnea indexes (AHI) and snoring. OSAS patients of Gaziantep were fat and severe OSAS patients who slept lightly but efficiently at lower oxygen levels with longer durations. They fell into Rapid Eye Movement (REM) sleep quickly. The number of hypopneas is high. OSAS patients of Adana sleep deeply, frequently wake after sleep onset, and snore less. The number of obstructive apnea is high. OSAS patients of Istanbul sleep efficiently but snore a lot. REM oxygen saturation, oxygen desaturation index (ODI) levels, and the average heart rate were high in Istanbul. The number of central and mixed apneas is high. Sleep patterns and oxygen measurements varied among clinical subtypes of patients with OSAS, as well as among provinces. Understanding regional or subtype-specific OSAS could alter practice because treatment can be planned according to the severity of OSAS.

Diagnostic Performance of a Type III Portable Monitoring Device for Obstructive Sleep Apnea in Pregnant Women: A Prospective Validation Study.

Rationale: Obstructive sleep apnea (OSA) during pregnancy is linked to negative maternal and neonatal outcomes. Diagnosing OSA in this population is particularly challenging. Portable monitoring devices (PMD) present a potential alternative to polysomnography (PSG), but their effectiveness in pregnant women is uncertain. Objective: To evaluate diagnostic accuracy of a PMD to detect OSA in pregnant women. Methods: A prospective study of 136 middle-aged pregnant women (34 ± 4 years) in their third trimester of pregnancy (34 ± 3 weeks) who underwent laboratory type III PMD and PSG simultaneously. Results: Using an apnea-hypopnea index (AHI) ≥5 event/h by PSG, OSA was diagnosed in 10.3% of women (mild OSA: 86%; moderate OSA: 14%). An acceptable positive correlation was found between both tests in the AHI (r = 0.787; p < 0.001) and oxygen desaturation index (ODI) (r = 0.806; p < 0.001). The agreement limits between PSG and type III PMD were -4.1 to 5.4 for AHI and -6.0 to 4.5 for ODI. The sensitivity and specificity of type III PMD for an AHI ≥5 events/h were 57.1% and 99.2%, respectively, with a positive predictive value (PPV) of 88.9% and a negative predictive value (NPV) of 95.3%. On a receiver operating characteristic curve, the best cutoff point of AHI by type III PMD to identify OSA according to PSG criteria was 2.25 events/h. The sensibility and specificity for this point were 85.7% and 88.5%, respectively, with a PPV of 46.2% and NPV of 98.2%. Conclusions: A type III PMD with an AHI cutoff of 5 events/h could be a good alternative for OSA diagnosis in pregnant women. Additionally, an AHI ≥2.25 event/h demonstrates good diagnostic performance, but its low positive predictive value suggests that it is more appropriate as a screening tool. Further studies are needed to validate this sleep study tool in pregnant women, particularly in home settings.

Evaluating the Improvement in Oxygen Desaturation Index During CPAP Titration Using Split Night Polysomnography in Patients with Obstructive Sleep Apnea and Cardiovascular Diseases

Evaluating the Improvement in Oxygen Desaturation Index During CPAP Titration Using Split Night Polysomnography in Patients with Obstructive Sleep Apnea and Cardiovascular Diseases

Investigating the Relationship between Nocturnal Enuresis and Sleep Disordered Breathing Using Polysomnography Data of 5-10 Year-Old Children Referred to Qazvin Children's Hospital, Iran

Background and Objective: Sleep is a critical biological necessity essential for maintaining both physical and mental health in humans. Given the prevalence of nocturnal enuresis (NE) in children, this study sought to explore its potential link to sleep-disordered breathing (SDB). Materials and Methods: This cross-sectional study involved children aged 5 to 10 years who visited Qazvin Children's Hospital, Iran, from 2016 to 2021. Data were gathered using the Iranian Children's Sleep Habits Questionnaire (CSHQ) completed by parents, alongside polysomnography (PSG) assessments conducted at the hospital. Children were catego- rized into two groups of with and without enuresis. The PSG data were analyzed to evaluate respiratory parameters in accordance with the American Academy of Sleep Medicine (AASM) guidelines. Results: Of 124 participants, 64 (51%) were boys, with an average (standard deviation) age of 82.2 (24.4) months. Ap- proximately 39.1% of the children experienced NE. Statistically significant correlations were found between NE and several factors: body mass index (BMI) (P = 0.025), total sleep time (P = 0.026), number of hypopneas (P &lt; 0.001), hypopnea index (P = 0.012), total apnea and hypopnea events (P = 0.004), and the overall apnea-hypopnea index (AHI) (P = 0.005). However, no significant association was established between the oxygen desaturation index, arousal index (AI), and mean oxygen saturation (P &gt; 0.05). Conclusion: The findings indicate an association between enuresis and obstructive sleep apnea (OSA), suggesting that treating OSA could ameliorate enuresis symptoms. Therefore, it is advisable to evaluate children with enuresis, particu- larly those who are obese, for OSA

Altitude-induced central sleep apnea does not affect mean sleep oxygen saturation in young healthy males.

At high-altitude, periodic breathing (PB) can occur during sleep in healthy individuals. PB is characterized by a cyclical ventilatory pattern that alternates between central sleep apnea and brief episodes of hyperventilation. The aim of this study was to evaluate the effect of periodic breathing on sleep SpO2. 36 healthy males subjects (median-age:26[24-28]years old, median BMI:22.7[21.1-23.8]Kg/m2) underwent a polysomnography at a simulated altitude of 3,500 meters(FiO2:13%). Correlations were sought between the Apnea-Hypopnea Index(AHI), Oxygen Desaturation Index(ODI), percentage of total sleep time spent in PB, and mean SpO2 throughout the entire sleep period by calculating the Spearman's rank correlation test. We identified 20 participants who had experienced at least 3 minutes of PB adjacent to at least 3 minutes of regular breathing(RB). We compared the mean SpO2 between the two respiratory patterns using Wilcoxon signed-rank test. At simulated-altitude, the subjects spent a median-IQR of 43.9[12.5-79.1]% of sleep in PB and the median-AHI was 77.3[31.4-127.5]/h. Median awake and asleep SpO2 were 75.4[24-28]% and 68.5[66.4-72.5]% respectively. We found no within subject difference in SpO2 between RB and PB periods (median-IQR RB vs PB: 67.2%{63.8-74.8%} vs 67.5%{64.5-73.9%},p=0.43). No significant correlation was found between the mean sleep SpO2 and AHI(n=36,rs=-0.19,p=0.26), ODI(n=36,rs=-0.23,p=0.18) or PB(n=36,rs=-0.07,p=0.67). Awake SpO2 was correlated with mean SpO2 during sleep(n=36,rs=0.55;p=0.001). PB per se does not have a detrimental effect on mean SpO2 in young healthy males. Correlation between awake and sleep SpO2, suggests that sleep SpO2 at high-altitude is primarily determined by baseline oxygen saturation rather than the respiratory pattern developed during sleep.

Comparative efficacy of sleep positional therapy, oral appliance therapy, and CPAP in obstructive sleep apnea: a meta-analysis of mean changes in key outcomes.

Obstructive sleep apnea (OSA) is commonly treated with continuous positive airway pressure (CPAP), though many patients struggle with adherence. Sleep positional therapy (SPT) offers a potential alternative, especially for positional OSA (POSA). This study aimed to compare the efficacy and safety of SPT with CPAP, oral appliance therapy (OAT), and placebo. Nineteen randomized controlled trials (RCTs) with 1,231 participants were included. Data extraction focused on changes in key outcomes such as apnea-hypopnea index (AHI), total sleep time (TST), oxygen desaturation index (ODI), and sleep architecture from pre- to post-intervention. Random-effects meta-analyses were conducted to compare mean changes between SPT and control groups (placebo, OAT, CPAP), with sensitivity analyses to assess heterogeneity. Sleep positional therapy (SPT) showed a significant reduction in AHI in the supine position compared to placebo (MD = -7.46, 95% CI: -11.42, -3.49), although no difference was observed in overall AHI between SPT and placebo or OAT. Compared to CPAP, SPT was less effective in reducing AHI, with a trend toward greater reductions in AHI favoring CPAP. SPT demonstrated a significant improvement in arousal index compared to OAT (MD = -7.11, 95% CI: -10.52, -3.71) and a lower risk of device-related complications compared to both OAT (OR = 0.54, 95% CI: 0.31, 0.95) and CPAP (OR = 0.29, 95% CI: 0.12, 0.72). However, SPT did not lead to significant improvements in TST or oxygen saturation parameters across comparisons. Sleep positional therapy (SPT) is a safe alternative for managing positional OSA, particularly for patients intolerant to CPAP, though it remains less effective than CPAP in reducing overall AHI and improving oxygenation.

Association of nocturnal oxygen saturation with coronary artery calcification: cross-sectional evidence from the population-based SESSA study among Japanese men

ObjectiveWe investigated the associations of nocturnal oxygen saturation (SpO2) with prevalence of coronary artery calcification (CAC) and its level of burden, and whether the associations differ by obesity and mediate...

The Risk Factors and Predictors of Chronic Obstructive Pulmonary Disease in Patients With Obstructive Sleep Apnea-Hypopnea Syndrome at Plateau.

OSAHS patients with COPD (i.e., overlap syndrome) have a significantly worse prognosis than those with OSAHS alone, and the role of plateau hypoxia in the occurrence of the disease is still unclear. This underscores the urgent need to explore the risk factors for the incidence of COPD in patients with OSAHS and to identify predictors for the occurrence of overlap syndrome at plateau. Fifty patients with OSAHS and 34 patients with overlap syndrome were enrolled in this study. Demographic, auxiliary examination, and laboratory data were collected. All patients enrolled were obstructive sleep apnea-hypopnea syndrome. The apnea-hypopnea index (AHI), the number of hypopnea, and the oxygen desaturation index were higher in the group of patients with overlap syndrome than in the group of patients with OSAHS. The mean pulse oxygen saturation was lower than that in the group of patients with OSAHS (p < 0.05). The right heart structure and function indexes (PASP, right atrial transverse diameter, RVTD, BNP, TNI) in patients with overlap syndrome were worse than those in patients with OSAHS (p < 0.05), and this worse cardiovascular status was positively correlated with inflammatory factors such as high-sensitivity C-reactive protein, IL-6, and PCT (p < 0.05). Binary logistic regression analysis indicated that PASP, smoking index, and AHI were independent risk factors for OSAHS developing into overlap syndrome. ROC curve showed that the area under the curve of the combination of the three markers for predicting overlap syndrome was 0.908 (95% CI 0.843-0.974, p = 0.000), with a sensitivity of 0.882 and a specificity of 0.820. The optimal cutoff values for PASP were 42.5 mmHg, 15 for the smoking index, and 25.65 for the AHI based on the Youden index. Our study reveals that overlap syndrome has more frequent nighttime hypopnea and hypoxia than OSAHS alone. The cardiovascular complications of overlapping syndromes at plateau are more pronounced, possibly due to the exacerbation of the systemic inflammatory response. The combination of PASP, smoking index, and AHI can be a powerful tool for predicting and assessing the occurrence of COPD in OSAHS patients from plateau populations in China. These findings have the potential to significantly improve the management and prognosis of patients with overlap syndrome.