Moderate Obstructive Sleep Apnea Patients Research Articles

Obstructive Sleep Apnea Treatment and the Evaluation of Clinical Effectiveness of Uniquely Designed Oral Appliance Therapy Device.

Continuous positive airway pressure (CPAP) has been considered first-line therapy for patients with obstructive sleep apnea (OSA); however, adherence to the therapy is suboptimal. Oral appliance therapy (OAT) is an alternative to CPAP that may lend to better patient adherence, quality of life, and overall patients' effectiveness of therapy. This was a prospective, single-site, non-randomized study to evaluate the clinical effectiveness of a uniquely designed OAT device with an embedded adherence tracking chip in the treatment of mild and moderate OSA patients over three months. The effectiveness of OAT therapy was defined as the numerical product of efficacy and adherence. The efficacy of the device was defined as the change from baseline in the apnea-hypopnea index (AHI). Adherence was based on usage for a minimum of 4 hours/night of use, for at least five out of seven nights a week. 45 participants fitted with the OAT device completed at least one follow-up visit and had recordable objective data. Average patient wearing time was 7 hours/night and a reduction of the AHI from 16.4 events/hour to 5.7 events/hour after three months of use.Mean disease alleviation (MDA), which serves as a measure of the overall therapeutic effectiveness, was 62% when looking at 4 hours/night of usage. As the comfort of the device is related to wearing time, subjective data indicated the optimum first-time fit of the device. The study OAT device was well tolerated throughout the study. When both efficacyand adherence are considered, OAT can be a clinically effective tool to treat OSA.

Appliances Therapy in Obstructive Sleep Apnoea: A Systematic Review and Meta-Analysis.

Obstructive sleep apnea (OSA) is a recurrent partial or complete obstruction of the upper airway during sleep caused by narrowing or collapse of the pharyngeal wall. It leads to microstimulation and oxyhemoglobin desaturation, resulting in sleepiness and loud snoring. OSA negatively affects the cardiovascular system and may contribute to neurocognitive impairment. The aim of this systematic review is to evaluate the effectiveness and efficacy of appliance therapy in obstructive sleep apnea. The effectiveness was assessed by using the Apnea Hypopnea Index (AHI). An electronic search of the Cochrane Library, PubMed, and Google Scholar was conducted between 1998 and 2021. Articles were independently assessed by three reviewers. The quality of a randomised control trial (RCT) is assessed using the Cochrane risk of bias method. The tool GRADE was used to achieve the desired level of confidence for each outcome reported.Several studies used continuous positive airway pressure (CPAP), mandibular advancement devices (MAD), and tongue retention devices (TRD). The meta-analysis included a total of six papers that met the inclusion criteria. Results showed that CPAP significantly improved AHI compared with an oral appliance (random effects: difference in means = 8.40, 95% CI = 7.21 to 9.60). It was also found that oral appliance (OA) therapy significantly improved AHI compared with baseline before appliance therapy (random effects: mean difference = 13.40, 95% CI = 10.87 to 15.93; p.00001). For mild to moderate OSA, CPAP is considered the gold standard. Our meta-analysis of six RCTs found favorable evidence for OSA patients receiving oral devices; however, they were less effective than CPAP. A subgroup analysis found that MAD may be a beneficial treatment for mild to moderate OSA patients who do not respond to CPAP. The findings suggest that oral appliances may be an effective treatment for OSA, especially in patients with mild to moderate OSA.

Characteristics of genioglossus neuromuscular activity in patients with obstructive sleep apnea during drug-induced sleep

Objective: To analyze genioglossus (GG) activation responses to the negative pressure of upper airway cavity during awake and different sleep stages in patients with different obstructive sleep apnea (OSA) graduation. Methods: This prospective cohort study started from August 2019 to January 2021, recruited 42 male OSA patients aged from 21 to 59 (38.77±8.42) years. After completing whole night polysomnography (PSG) and upper airway CT, each subject underwent drug-induced sleep with simultaneous monitoring of genioglossal electromyography (GGEMG) and pressure of epiglottis (Pepi). Subjects were divided into three groups of mild OSA(7 males), moderate OSA(12 males), and severe OSA(23 males). The differences in upper airway CT measurements, parameters of GGEMG and Pepi during awake and induced sleep were compared. Statistical analysis was conducted by SPSS 21.0. Results: There was no significant difference in the GGEMG parameters between the mild and moderate groups. In wakefulness, the peak phasic GGEMG of the severe group was higher than the mild group (t=1.249, P=0.025), with no statistically difference in the corresponding Pepi. In the sleep onset, the GGEMG parameters and Pepi in severe group were higher than the other two groups. Linear regression analysis of the maximum GGEMG and maximum Pepi at the end of obstructive apnea (OA) in all moderate plus severe patients (n=35) was shown nonlinear correlation (r=0.28, P=0.694). The airway length of the glossopharyngeal cavity was linearly correlated with the maximum Pepi of OA (r=0.468, R2=0.219, P=0.005). Conclusions: The individual difference of GG activation in OSA patients is related to the severity of the disease (frequency of respiratory events) and negative pressure stimulation. In moderate and severe OSA patients, GG activity is not in harmony with the corresponding negative pressure stimulation, which may be one of the mechanisms leading to the aggravation of OSA.

Association Between Sleep Efficiency and Hypertension in Chinese Obstructive Sleep Apnea Patients.

We aimed to explore the relationship of sleep efficiency (SE) with the prevalence of hypertension in Chinese obstructive sleep apnea (OSA) patients based on polysomnography (PSG) records. We studied 2360 patients with OSA and 764 primary snorers who underwent PSG in our hospital. SE was divided into three grades, including ≥85%, 80%~84.9%, and <80%. Hypertension was defined based either on direct blood pressure measurements, under anti-hypertensive treatments or on physician diagnosis. Multivariate logistic regression models were conducted to investigate the association between SE and hypertension. After adjusting for potential confounding factors, OSA patients with <80% SE and those with 80% to 84.9% SE were significantly associated with the prevalence of hypertension (OR = 1.248, 95% CI 1.018~1.531, P=0.033; OR = 1.380, 95% CI 1.040~1.832, P=0.026). Compared to primary snorers, OSA combined with <85% SE increased the odds of hypertension. In stratified analysis by SE, risk of hypertension only in those with <80% SE was significantly different between OSA and primary snorers. Furthermore, this relationship between reduced SE and hypertension was evident especially in female, younger ages, obese, moderate and severe OSA patients. No significant relationship between reduced SE and hypertension was found in primary snores group. We found that poor SE was correlated with the prevalence of hypertension in Chinese OSA patients, but not in those with primary snoring. Moreover, this relationship was evident especially in female, younger ages, obese, moderate and severe OSA patients.

Clinical application of headache impact test (HIT)-6 and epworth sleepiness scale (ESS) for sleep apnea headache

BackgroundSleep apnea headache is a major symptom accompanying obstructive sleep apnea (OSA), but relatively little evidence has been reported on the magnitude of its negative effects on patients or the evaluation of therapeutic effects. We quantitatively assessed sleep apnea headache using the Epworth sleepiness scale (ESS) and headache impact test (HIT)-6.MethodsThe first part of this study enrolled 86 patients (72 male; mean [± standard deviation] age 53.2 ± 13.8 years) who had been diagnosed with OSA by polysomnography in our sleep center and investigated the prevalence and characteristics of sleep apnea headache. The second part enrolled 21 patients (12 male; mean age, 47.5 ± 13.0 years) diagnosed with sleep apnea headache by polysomnography and/or peripheral arterial tonometry and evaluated the effects of OSA therapy on headache. Medical records including ESS, HIT-6, and polysomnographic data were retrospectively analyzed.ResultsThe prevalence of sleep apnea headache among OSA patients was 22.1%, and was higher in female (50.0%) than in male (16.7%). The proportion of N3 and HIT-6 score showed a significant negative correlation (Pearson’s R = -0.51, p < 0.05). In female, median apnea–hypopnea index (AHI) was significantly lower in patients with headache (26.1 /h [interquartile range 21.4–29.6 /h]) than in patients without (54.2 /h [41.3–73.9 /h], p < 0.05, Wilcoxon rank-sum test). HIT-6 and ESS scores improved from 56.4 ± 9.7 to 45.9 ± 8.4 and from 9.0 ± 4.4 to 5.3 ± 4.2 in patients with oral appliance (OA), and from 54.3 ± 10.7 to 44.6 ± 6.1 and from 10.0 ± 4.0 to 4.9 ± 2.9 with continuous positive airway pressure (CPAP). In patients with good CPAP adherence, these scores improved from 58.1 ± 10.8 to 44.0 ± 6.0 and from 9.6 ± 3.8 to 3.6 ± 1.7.ConclusionAmong patients with OSA, prevalence of sleep apnea headache was higher in female than in male. In female, headache was associated with relatively mild OSA. OA showed substantial effects on headache in mild to moderate OSA patients. CPAP adherence was important for improving the headache. HIT-6 score appears useful for the diagnosis and management of sleep apnea headache.

Comparative evaluation of the efficacy of customized maxillary oral appliance with mandibular advancement appliance as a treatment modality for moderate obstructive sleep apnea patients—a randomized controlled trial

BackgroundObstructive sleep apnea (OSA) is quite common among the adult population, according to recent epidemiological studies. The most frequently suggested alternate treatment for mild to moderate OSA is oral appliances (OA). The purpose of the present study was to assess as well as compare the effectiveness of custom-made maxillary oral appliances against mandibular advancement appliances in the care of individuals suffering from moderate obstructive sleep apnea.MethodsA prospective interventional research was carried out with 40 participants. Polysomnography (PSG) was done and the participants with an apnea-hypopnea index (AHI) >15–30 were involved in the research. Study participants were randomly split up into two test groups: group I was the “Control Group” (group treated with a mandibular advancement device (MAD), n=20), while group II was exposed to a “customized maxillary oral appliance” (CMOA, n=20). Both groups had reference measures for AHI, blood oxygen saturation (SpO2), oro-nasal airflow via respiratory disturbance index (RDI), and the Epworth Sleepiness Scale (ESS). Appliances were fabricated and delivered to the respective study group participants. PSG was again conducted after a period of 1 and 3 months of appliance delivery and re-evaluation was done for all the parameters and was compared with reference measurements. The facts were analyzed using descriptive and analytical statistical methods. The statistical program utilized in the study was “SPSS (Statistical Package for Social Sciences) Version 20.1.” After 1 and 3 months, the statistical significance between the two study groups was assessed at P<0.05.ResultsThe analysis of mean AHI, SPO2, RDI, and ESS for both test groups manifested statistically significant measures (P<0.001). The study results revealed a statistically significant depletion in mean AHI scores, improvement in mean SPO2 scores, and reduction in mean RDI scores and ESS scores when compared with reference measurements to 1 month, 1 to 3 months, and between reference measurements and 3 months.ConclusionThe CMOA was effective in managing moderate OSA and has great therapeutic potential. It can be an option for the MAD for treating patients suffering from moderate obstructive sleep apnea.Trial registrationThe study was registered under Clinical Trials Registry-India and the registration number is CTRI/2020/07/026936. Registered on 31 July 2020

Sensorimotor Cortical Activity during Respiratory Arousals in Obstructive Sleep Apnea.

Intensity of respiratory cortical arousals (RCA) is a pathophysiologic trait in obstructive sleep apnea (OSA) patients. We investigated the brain oscillatory features related to respiratory arousals in moderate and severe OSA. Raw electroencephalography (EEG) data recorded during polysomnography (PSG) of 102 OSA patients (32 females, mean age 51.6 ± 12 years) were retrospectively analyzed. Among all patients, 47 had moderate (respiratory distress index, RDI = 15−30/h) and 55 had severe (RDI > 30/h) OSA. Twenty RCA per sleep stage in each patient were randomly selected and a total of 10131 RCAs were analyzed. EEG signals obtained during, five seconds before and after the occurrence of each arousal were analyzed. The entropy (approximate (ApEn) and spectral (SpEn)) during each sleep stage (N1, N2 and REM) and area under the curve (AUC) of the EEG signal during the RCA was computed. Severe OSA compared to moderate OSA patients showed a significant decrease (p < 0.0001) in the AUC of the EEG signal during the RCA. Similarly, a significant decrease in spectral entropy, both before and after the RCA was observed, was observed in severe OSA patients when compared to moderate OSA patients. Contrarily, the approximate entropy showed an inverse pattern. The highest increase in approximate entropy was found in sleep stage N1. In conclusion, the dynamic range of sensorimotor cortical activity during respiratory arousals is sleep-stage specific, dependent on the frequency of respiratory events and uncoupled from autonomic activation. These findings could be useful for differential diagnosis of severe OSA from moderate OSA.

Time Under 90% Oxygen Saturation and Systemic Hypertension in Patients with Obstructive Sleep Apnea Syndrome.

The diagnosis and severity of obstructive sleep apnea (OSA) are commonly based on the apnea hypopnea index (AHI). However, patients with similar severity AHIs may show widely varying comorbidities and risks for cardiovascular disease, which may be associated with different severities of nocturnal hypoxia. The percentage of cumulative time with oxygen saturation below 90% in total sleep time (T90) is receiving increasing attention in OSA research because it describes the duration and degree of hypoxia during the whole sleep. This study aimed to explore the distribution of T90 in OSA patients with similar severity and to evaluate the relationship between T90 and hypertension. A total of 775 patients with OSA were enrolled in this study, all participants were divided into groups according to the T90 value: light hypoxia (T90≤5%), mild hypoxia (T90 accounted for 5-10%), moderate hypoxia (T90 accounted for 10-25%), and severe hypoxia (T90>25%). Multivariate logistic regression analysis was performed to assess the association between T90 and hypertension. Of the patients with mild OSA, 94.33% had light hypoxia, and 88.64% of moderate OSA patients had light hypoxia. The proportions of light, mild, moderate, and severe hypoxia among patients with severe OSA were 28.60%, 17.69%, 21.40%, and 32.31%, respectively. After adjustment for potential confounders, the risk of hypertension in patients with severe OSA increased according to the severity categories of T90. The odds ratio for T90 accounting for 10-25% relative to T90≤5% was 2.544 (95%confidence interval, 1.254-5.164; P=0.010) and as high as 2.692 (95%confidence interval, 1.403-5.166; P=0.003) in patients with T90>25%. OSA patients with similar degree of AHI may have different T90 values, especially in severe OSA. A higher T90 was independently associated with the risk of hypertension after adjustment for traditional risk factors in patients with severe OSA. Our findings highlight the potential role for T90 in predicting hypertension in patients severe OSA.

Dynamic regional homogeneity alterations and cognitive impairment in patients with moderate and severe obstructive sleep apnea.

Background and purposePrevious studies have found that abnormal local spontaneous brain activity in patients with obstructive sleep apnea (OSA) was associated with cognitive impairment, and dynamic functional connections can capture the time changes of functional connections during magnetic resonance imaging acquisition. The purpose of this study was to investigate the dynamic characteristics of regional brain connectivity and its relationship with cognitive function in patients with OSA and to explore whether the dynamic changes can be used to distinguish them from healthy controls (HCs).MethodsSeventy-nine moderate and severe male OSA patients without any treatment and 84 HCs with similar age and education were recruited, and clinical data and resting functional magnetic resonance imaging data were collected. The dynamic regional homogeneity (dReHo) was calculated using a sliding window technique, and a double-sample t-test was used to test the difference in the dReHo map between OSA patients and HCs. We explored the relationship between dReHo and clinical and cognitive function in OSA patients using Pearson correlation analysis. A support vector machine was used to classify the OSA patients and HCs based on abnormal dReHo.ResultCompared with HCs, OSA patients exhibited higher dReHo values in the right medial frontal gyrus and significantly lower dReHo values in the right putamen, right superior temporal gyrus, right cingulate gyrus, left insula and left precuneus. The correlation analysis showed that the abnormal dReHo values in multiple brain regions in patients with OSA were significantly correlated with nadir oxygen saturation, the oxygen depletion index, sleep period time, and Montreal cognitive assessment score. The support vector machine classification accuracy based on the dReHo difference in brain regions was 81.60%, precision was 81.01%, sensitivity was 81.01%, specificity was 82.14%, and area under the curve was 0.89.ConclusionThe results of this study suggested that there was abnormal dynamic regional spontaneous brain activity in patients with OSA, which was related to clinical and cognitive evaluation and can be used to distinguish OSA patients from HCs. The dReHo is a potential objective neuroimaging marker for patients with OSA that can further the understanding of the neuropathological mechanism of patients with OSA.

Assessment of bone mineral density and bone metabolism in young men with obstructive sleep apnea: a cross-sectional study

BackgroundHypoxia in obstructive sleep apnea (OSA) patients during sleep may have an effect on bone metabolism. Few data regarding evaluation of bone metabolism in young individuals diagnosed with OSA. In this study, we aim to identify the association between bone mineral density and OSA in young men (≤ 40 years old of age).MethodsConsecutive male subjects who underwent polysomnography were enrolled. Serum calcium, 25-hydroxyvitamin-D3, β-isomerized form C-terminal telopeptide of type I collagen, osteocalcin and procollagen type 1 N-propeptide were measured in all participants, and bone mineral density (BMD) at lumbar spine (L1-L4), femoral neck and hip total were determined by dual energy X-ray absorption (DXA).ResultsThe population consisted of 85 subjects (mean age 35.53 years). The BMD at lumbar spine (L1-L4) in moderate OSA patients was higher than control and severe OSA group significantly (p = 0.036). After adjustment for confounding factors, stepwise multiple linear regression analyses showed LaSO2 (β = 0.340, p = 0.008) as an independent explanatory variable for Lumbar L1–L4 BMD, LaSO2 (β = 0.304, p = 0.037), BMI (β = 0.393, p = 0.008) for femur neck BMD and BMI (β = 0.720, p = 0.002) for hip total BMD. Conclusions.Our finding indicated that there was a relationship between OSA and bone metabolism in younger men, and moderate OSA-related hypoxia positively related with BMD. This study also showed that different degrees of recurrent hypoxia had different effects on bone metabolism, a finding that required further investigation.

Comparative evaluation of the efficacy of customized maxillary oral appliance with mandibular advancement appliance as a treatment modality for moderate obstructive sleep apnea patients\u2014protocol for a randomized controlled trial

BackgroundObstructive sleep apnea (OSA) is due to the obstruction of the upper airway during sleep. This condition is often associated with multiple symptoms and co-morbidities. There are many treatment options mentioned in the literature to manage OSA, among which interventional option of continuous positive airflow (CPAP) and non-interventional option, i.e., mandibular advancement device (MAD), which is an oral appliance (OA), are the most preferred ones. This study aims to evaluate the efficacy of customized maxillary oral appliances with mandibular advancement devices in moderate OSA patients.MethodsA prospective interventional study with a randomized controlled trial will be carried out involving 40 participants (sample size), with an apnea-hypopnea index (AHI) > 15–30, recorded on polysomnography (PSG). Study participants will be randomly divided into the following treatment groups: control group or group subjected to mandibular advancement device (MAD, n=20) and second group subjected to customized maxillary oral appliance (CMOA, n=20). Baseline assessment of apnea/hypopnea index (AHI), oxygen saturation in blood, percentage of rapid eye movement, electroencephalogram, electrocardiogram, oro-nasal airflow via a pressure transducer, and Epworth Sleepiness Scale will be done. Then both study group participants will receive their respective appliances. And after one month and three months of delivery of the appliance, all the parameters, i.e., AHI, oxygen saturation in blood, percentage of rapid eye movement, electroencephalogram, electrocardiogram, oro-nasal airflow via a pressure transducer, and Epworth Sleepiness Scale will be re-evaluated and compared with the baseline measurements. Descriptive and analytical statistics will be done. SPSS (Statistical Package for Social Sciences) Version 20.1 will be used as statistical software. The statistical significance between the two groups after one month and three months will be evaluated at p< 0.05.DiscussionWe expect, customized maxillary oral appliance to be more efficient in managing moderate OSA, in comparison with MAD. If the hypothesis of the present study is confirmed, then this customized maxillary appliance will be quoted as a “gold standard” for managing moderate OSA.Trial registrationCTRI/2020/07/026936 Registered 31 July 2020.

Association between obstructive sleep apnea and male serum testosterone: A systematic review and meta-analysis.

Currently, there is no consensus on the effect of obstructive sleep apnea on male serum testosterone levels. This systematic review and meta-analysis aimed to determine the association between obstructive sleep apnea and male serum testosterone level. The literature related to obstructive sleep apnea and male serum testosterone in the PubMed, Embase, and Cochrane Library databases were searched from their inception to June 10, 2021. Data were pooled using the Stata 15 software. We performed a subgroup analysis of studies after matching the age and body mass index, as well as according to the severity of obstructive sleep apnea. Eighteen studies involving 1823 men were included in the systematic review and meta-analysis. A significant inverse association between obstructive sleep apnea and male serum testosterone (SMD = -0.76; 95% CI: -1.18, -0.33; p = 0.001) was found. After adjusting for age and body mass index, this inverse association still existed (SMD = -0.8; 95% CI = -1.41, -0.18, p = 0.012). According to the subgroup analysis of obstructive sleep apnea severity, our results showed that serum testosterone was not significantly decreased in mild (SMD = -0.58; 95% CI = -1.88, 0.73, p = 0.386) and moderate obstructive sleep apnea patients (SMD = -0.94; 95% CI = -2.04, 0.15, p = 0.092), whereas it was significantly reduced in patients with severe obstructive sleep apnea (SMD = -1.21; 95% CI = -2.02, -0.41, p = 0.003). Obstructive sleep apnea is inversely associated with male serum testosterone levels, independent of body mass index and age. Notably, the severity of obstructive sleep apnea is also correlated with male serum testosterone, which is significantly reduced in patients with severe obstructive sleep apnea.

Clinical Factors Associated with Very Severe Obstructive Sleep Apnea in Mongolian Patients: A Case-Control Study

Objectives: To determine risk factors and clinical characteristics of obstructive sleep apnea patients (OSA) according to the severity of the value of AHI ≥ 60 (Apnea-Hypopnea Index). Methods: A hospital-based, case-control study, December 2018 - 2020. Patients were grouped by severity of AHI as moderate, severe, and very severe. Results: Of 103 male cases, 52 were very severe obstructive sleep apnea (vsOSA). The control group consisted of 16 moderate OSA (mOSA) and 35 severe OSA (sOSA) patients. The case group consisted of 52 vsOSA patients. The average age was 48.7 ± 12.6. There was statistically significant increased body mass index (p &lt; 0.003), systolic blood pressure, and abdominal circumference (p &lt; 0.006) in the vsOSA group. Moreover, on polysomnography there was less deep sleep (p &lt; 0.004), a greater arousal index (p &lt; 0.000), higher apnea-hypopnea index (p &lt; 0.000), and higher night systole pressure (p &lt; 0.010). According to a bivariate analysis, abdominal circumferences were the variable with the closest association to the vsOSA group (crude OR: 9.14, p &gt; 0.004), followed by decreased maximum saturation of O2 (crude OR: 6.6, p &gt; 0.451). Conclusion: Of male OSA patients, 50.1% have vsOSA (AHI &gt; 60) and most of them were obese and suffered from high blood pressure. Lower levels of O2 saturation and increased abdominal and neck circumferences were significant risk factors for the very severe obstructive sleep apnea group.

The effect of oropharyngeal exercise in patients with moderate and severe obstructive sleep apnea using CPAP: a randomized controlled study.

Obstructive sleep apnea (OSA) is an important public health problem. Beyond common treatment options, solution-oriented options are needed. Oropharyngeal exercise training may be a research area in this respect. This study aimed to evaluate the effects of oropharyngeal exercise (OPE) in addition to continuous positive airway pressure (CPAP) therapy in patients diagnosed with OSA. Patients with moderate and severe OSA were screened from the electronic database of our hospital and 41 patients (20: exercise group; 21: control group) were included in the study. Each patient was assessed with CPAP usage time, maximal voluntary ventilation (MVV), maximum inspiratory and expiratory pressure (MIP-MEP), neck circumference, body mass index (BMI), waist-hip ratio, Epworth sleepiness score, Pittsburgh sleep quality index (PSQI), and short-form health survey (SF-36) in the first visit. The OPE was prescribed in addition to CPAP for the exercise group and performed by the patients for 3months. At the end of the third month, groups were re-assessed with the same parameters. Most of the patients were men, and the mean age of the study population was 51.9 ± 7.4; the mean apnea-hypopnea index (AHI) in the last polysomnography report was 53.3 ± 27.4. In the exercise group, MVV (p = 0.003), MIP (p = 0.002), MEP (p = 0.024), and SF-36 energy/fatigue (p = 0.020) were observed to increase while the total PSQI score (p = 0.036) decreased. The neck circumference (p = 0.006) and BMI (p = 0.013) were found to be significantly decreased in the exercise group. We found that OPE training may have improved respiratory muscle strength as well as sleep quality and health-related quality of life in the exercise group. OPE along with CPAP therapy may be recommended in moderate and severe OSA patients who are willing to participate.

Contribution of sleep characteristics to the association between obstructive sleep apnea and dyslipidemia

Objectives/backgroundLittle information is available about the association of obstructive sleep apnea (OSA) with atherogenic dyslipidemia and the contribution of sleep characteristics to lipid alterations. We compare dyslipidemia prevalence among non-apneic subjects and mild-severe OSA patients to identify the sleep characteristics that are independently associated with dyslipidemia and serum lipid levels in OSA patients. Patients/methodsWe recruited 809 consecutive patients who had been referred for polysomnography study by OSA suspicion. Anthropometric characteristics, body composition and comorbidities were recorded. Spirometry and 24-h ambulatory blood pressure monitoring were performed the same day of the sleep study. The day after attended polysomnography, fasting blood samples were drawn to measure the lipid profile. ResultsDyslipidemia prevalence increased with the presence of OSA, from non-OSA subjects to mild, moderate and severe OSA patients (31%, 33%, 42% and 51%, respectively; p < 0.001). After adjusting for sex, age, body mass index and smoking habit, only severe OSA had an independent association with dyslipidemia when compared to non-OSA subjects (adjusted odds ratio 1.71, 95%CI 1.09 to 2.69, p = 0.019). In OSA patients, multivariate logistic regression identified active smoking, apnea-hypopnea index (AHI) and mean nocturnal saturation as variables independently associated with dyslipidemia. However, in these patients, arousal index, slow wave sleep duration and REM latency were also independently associated with cholesterol and low-density lipoprotein levels. ConclusionsThe association between dyslipidemia and OSA is limited to severe patients, with high AHI and nocturnal hypoxemia. However, sleep fragmentation and increased sympathetic activity could also contribute to OSA-related lipid dysregulation.

Role of Neutrophil to Lymphocyte Ratio in Predicting Severity of Obstructive Sleep Apnea.

Obstructive sleep apnea (OSA) has been linked to and is associated with increased cardiovascular and cerebrovascular morbidity. Ongoing inflammatory responses play an important role in this association. Systemic inflammation is important in pathophysiology of OSA and its comorbidity. In this study, we aimed to evaluate the role of neutrophil-to-lymphocyte ratio (NLR) in OSA patients and comparing with other well-known inflammatory marker, C-reactive protein (CRP) along with thyroid-stimulating hormone(TSH) and body-mass index(BMI). We conducted a retrospective analysis of 162 patients with OSA and divided them into 2 categories based on apnea-hypopnea index (AHI) (< 30 and > = 30), and recorded their leukocyte profiles, sex, age and body mass index. 80 matched healthy controls were taken. Patients were excluded if they had underlying cancer, chronic inflammatory disease, any systemic infection, uncontrolled hypertension and diabetes mellitus, a known acute coronary syndrome, valvular heart disease, renal or hepatic dysfunction. We found that N/L Ratio in severe OSA patients was significantly higher compared with mild and moderate OSA patients and healthy controls (p < 0.001). CRP levels were not different in all OSA stages (p = 0.595). We noted a significant difference in mean BMI of the two groups. In the wake of increase in prevalence of OSA in a developing country like India coupled with inadequate proportion of sleep labs, NLR is an inexpensive, easy to obtain, widely available marker of inflammation that might in combination with other markers assist in identifying patients with severe OSA.

A novel parameter is better than the AHI to assess nocturnal hypoxaemia and excessive daytime sleepiness in obstructive sleep apnoea

To evaluate whether the percentage of total sleep time spent with apnoea and hypopnoea duration time (AHT%) is better than the apnoea-hypopnoea index (AHI) for the assessment of nocturnal hypoxaemia and excessive daytime sleepiness (EDS) in patients with obstructive sleep apnoea (OSA). Patients with suspected OSA were enrolled. Polysomnography, Epworth Sleepiness Scale, self-administered surveys and anthropometric measures were performed. The efficiency of AHT% and the AHI was evaluated for nocturnal hypoxaemia and EDS. A total of 160 eligible participants were analysed. The median AHT% in normal, mild, moderate and severe OSA patients was significantly different in the four-group patients with OSA. Spearman rank correlations analysis found that the associations were stronger between AHT% with percentage of total sleep time and O2 saturation of < 90% and minimum nocturnal oxygen saturation than these parameters with the AHI. AHT% had a greater area under the curve than the AHI for predicting EDS in patients with OSA. AHT% was significantly higher in the EDS group. We present a novel parameter, AHT%, to evaluate nocturnal hypoxaemia and EDS in OSA patients. AHT% partially compensates for the shortcomings of the AHI. AHT% is better than the AHI for assessing nocturnal hypoxaemia and EDS. AHT% reflects different clinical characteristics associated with OSA from a new perspective.

Women with OSA have higher chances of having metabolic syndrome than men: effect of gender on syndrome Z in cross sectional study

Study objectivesThis study was done to find out prevalence of Metabolic syndrome (MS) in patients with Obstructive Sleep Apnea (OSA) and whether there is any difference in prevalence of syndrome Z in male and female. MethodologyAll consecutive diagnosed patients with OSA between June 2015 and Oct 2019 were screened for metabolic syndrome and factors associated with metabolic syndrome in OSA were analyzed. ResultsDuring study period, 502 patients (357 males; 145 females) were diagnosed with OSA. Mean age was 51.88 ± 12.18 years (females and males:55.91 ± 9.74 and 50.24 ± 12.70 years, respectively). Mean BMI was 31.60 ± 11.09 kg/m2 (female: 35.29 ± 7.19 and male: 30.1 ± 12.0 kg/m2) (p < 0.001). Mean AHI was 62.67 ± 35.22. Mild, moderate and severe category of OSA constituted 7.3%, 15.3% and 77.4% respectively. MS was found in 72.7% (365 out of 502) individuals with OSA. MS was found in 75.8%, 68.4 and 48.7% in severe, moderate and mild OSA patients respectively (p < 0.001). Females OSA patients had significantly high percentage (88.27%) of metabolic syndrome compared to males OSA patients (66.38%) {p < 0.001}. Female patients with SZ had higher metabolic score (p = 0.019) and were older (p < 0.001). ConclusionMetabolic syndrome is highly prevalent in OSA population (72.7%) and is much more common in female OSA patients (88%) than males OSA (68%). All OSA patients should be screened for MS so that early intervention can be done in these patients so as to prevent cardiovascular complications.

Randomized Trial of 2 Self-Titrated Oral Appliances for Airway Management

The effectiveness and predictability of 2 different oral appliance (OA) designs to reduce the respiratory event index (REI) in moderate and severe obstructive sleep apnea (OSA) patients requires elucidation. The primary aim of the trial was to determine if 2 widely used midline-traction and bilateral-thrust OA designs differ in effectiveness to reduce the REI within a single test population categorized by OSA severity. Moderate and severe adult OSA patients, who were previously prescribed continuous positive airway pressure therapy (CPAP) but were dissatisfied with it (n = 56), were studied by home-polygraphy in a randomized crossover trial using either midline-traction with restricted mouth opening (MR) or bilateral thrust with opening permitted (BP) design OAs. OAs were used nightly for 4 wk (T2) followed by a 1-wk washout period, then 4 wk (T4) using the alternate OA. REI and oxygen saturation (SaO2) were primary outcomes, while predictability and efficacy comparison of the 2 OAs were secondary outcomes. Thirty-six participants had used MR and BP OAs during both 4-wk study legs. Twenty (55.6%) MR OA-using participants, 25 (69.4%) BP OA-using participants, and 16 (44.4%) participants using both OAs had significant REI reductions. Overall baseline (T0) median REI (interquartile range) of 33.7 (20.7–54.9) was reduced to 18.0 (8.5–19.4) at T2 and to 12.5 (8.2–15.9) at T4 (P < 0.001). Comparison of the 2 sequence groups’ (MR-BP and BP-MR) REI showed the median differences between T0 and T2 and T4 were highly significant (P < 0.001). Regression analysis predicted about half of all users will have REIs between 8 and 16 after 2 mo. Baseline overjet measures >2.9 mm predicted greater OA advancement at T4. Mean and minimum SaO2 did not change significantly from T0 to T2 or T4. MR and BP OA designs similarly attenuated REI in moderate and severe OSA individuals who completed the 8-wk study protocol with greater REI reduction in those with severe OSA (ClinicalTrials.gov NCT03219034).

Long-term Effects of Gastric Bypass Surgery in Patients with Obstructive Sleep Apnea

Background: Obstructive sleep apnea is a common disorder involving, intermittent mechanical obstruction of the upper airway during sleep. Obesity is the most powerful risk factor for obstructive sleep apnea. Objective: This study aimed to investigate the long-term effect of Roux-en-Y gastric bypass bariatric surgery on patients with obstructive sleep apnea. Methods: This study included patients were referred for bariatric surgery (Roux-en-Y gastric bypass) to control symptoms and complications of obesity during a 5-year period. An overnight sleep study was performed for each patient before and after the bariatric surgery, to study its effect on different obstructive sleep apnea-related variables. Results: This study included 179 patients (mean age 35.9 ± 10.7 years). The mean duration from preoperative assessment to postoperative assessment was 2.4 ± 2.2 years. The mean change in body mass index and weight showed a decrease of 16.0 ± 16.0 kg/m2 and48.7 ± 25.9 kg, respectively. The apnea hypopnea index decreased by a mean of 22.6 ± 26.3 events/hour. Conclusion: We concluded that a decrease in the body mass index by 1 kg/m2 could predict a decrease in the apnea hypopnea index by 0.46 events/hour. Moreover, after mean follow-up duration of 2.4 years, 84.3% of mild and 83.3% of moderate obstructive sleep apnea patients became normal postoperatively.