Increased Apnea-hypopnea Index Research Articles

Sleep Bruxism and Sleep Structure in Comorbid Insomnia and Obstructive Sleep Apnea (COMISA) Syndrome: A Polysomnographic Study.

Introduction: Comorbid insomnia and obstructive sleep apnea (COMISA) is not a well-identified sleep disorder, despite having a significant impact on health. This study investigates the relationship between sleep bruxism (SB) and sleep architecture in patients with COMISA, obstructive sleep apnea (OSA), and in those without any sleep disorders. Methods: 119 patients were included in the study and divided into three groups: OSA, COMISA, and a control group. Polysomnographic (PSG) examination provided parameters related to sleep architecture, OSA, and characteristics of SB. Results: The bruxism episode index (BEI) and other SB parameters were not found to be statistically different between the three groups (p > 0.05). There was no statistical difference in measured sleep architecture between the COMISA and OSA groups (p > 0.05). In comparison to the control group, participants in the COMISA group were found to have an increased apnea-hypopnea index (AHI), oxygen desaturation index (ODI), respiratory disturbance index (RDI), all arousals (AA), and respiratory arousals (RA) (p < 0.05). Among COMISA patients, AA and RA were shown to have a positive linear correlation with the number of bradycardia events per hour (r = 0.49, r = 0.48, p < 0.05). Conclusions: SB does not occur in patients with COMISA more frequently than in patients with OSA or those without any sleep disorders. PSG parameters are not specific for COMISA; therefore, in order to differentiate this disorder from OSA alone, a comprehensive patient assessment has to be performed.

Predictive factors and screening strategy for obstructive sleep apnea in patients with advanced multiple sclerosis

BackgroundObstructive sleep apnea (OSA) screening questionnaires have been evaluated in Multiple Sclerosis (MS) but not yet validated in patients with advanced disease. The aim of this study is to identify OSA predictive factors in advanced MS and to discuss screening strategies. MethodsOximetry data from 125 patients were retrospectively derived from polysomnographic reports. Univariate and multivariate analysis were used to determine predictive factors for OSA. A two-level screening model was assessed combining the oxygen desaturation index (ODI) and a method of visual analysis. Resultsmultivariate analysis showed that among the clinical factors only age and snoring were associated with OSA. Usual predictive factors such as sleepiness, Body mass index (BMI) or sex were not significantly associated with increased Apnea Hypopnea Index (AHI). The ODI was highly predictive (p < 0.0001) and correctly identified 84.1 % of patients with moderate OSA and 93.8 % with severe OSA. The visual analysis model combined with the ODI did not outperform the properties of ODI used alone. ConclusionAs the usual clinical predictors are not associated with OSA in patients with advanced MS, questionnaires developed for the general population are not appropriate in these patients. Nocturnal oximetry seems a pertinent, ambulatory and accessible method for OSA screening in this population.

Restless legs syndrome in patients with obstructive sleep apnea: Association between apnea severity and symptoms of depression, insomnia, and daytime sleepiness

ObjectiveTo determine if the prevalence and severity of restless legs syndrome (RLS) varies with apnea severity and analyze differences between the sexes in terms of comorbid RLS with symptoms of depression, insomnia, and daytime sleepiness in patients with obstructive sleep apnea (OSA). MethodsSymptoms of depression, insomnia, and daytime sleepiness were defined as Patient Health Questionnaire–9 score ≥10, Insomnia Severity Index score ≥15, and Epworth Sleepiness Scale score ≥11. Multivariate logistic and linear regression analyses were conducted. ResultsIn 707 adults with OSA (85.1% males), 16.1% (n = 114) had comorbid RLS. The prevalence of RLS was markedly lower in those with moderate and severe OSA than in those with mild OSA. Similarly, the odds of RLS significantly decreased with increasing apnea-hypopnea index. After controlling for age and sex, in patients with comorbid RLS, the International RLS Study Group Rating Scale scores were negatively correlated with apnea-hypopnea index and a nadir peripheral oxygen saturation during sleep. The presence of RLS was more likely to be associated with symptoms of depression, insomnia, and daytime sleepiness after controlling for confounding variables, but only in men. ConclusionsRLS is frequently noted in combination with OSA, with a female preponderance. The severities of OSA and RLS may be negatively associated. In patients with OSA, sex-related differences in terms of comorbid RLS with symptoms of depression, insomnia, and daytime sleepiness warrant further investigations.

Role of neck radiography in assessing recurrent/residual adenoid hypertrophy in children with OSA and history of adenotonsillectomy: a sleep physician perspective.

Recurrent/residual adenoid hypertrophy after adenotonsillectomy in children can result in obstructive sleep apnea (OSA). We aimed to assess the role of soft tissue neck X-ray (STN-XR) in evaluating recurrent/residual adenoid tissue hypertrophy. This was a single-center retrospective study that included children with sleep study-confirmed OSA and a known history of adenotonsillectomy who underwent STN-XR to evaluate for recurrent/residual adenoid tissue hypertrophy. STN-XR nasopharyngeal obliteration and baseline polysomnographic data were analyzed. Multiple linear regression was used to assess the independent relationship between the results of STN-XR and the total apnea-hypopnea index, while controlling for relevant characteristics. The study included 160 participants with a median age of 10 years (quartile [Q] 1 = 7, Q3 = 12.25). More than half of the children were male (59.4%) and the median body mass index z-score was 2.11 (Q1 = 1.23, Q3 = 2.54). STN-XR was normal in 39.4%, and it showed mild, moderate, and complete nasopharyngeal obliteration in 20.6%, 32.5%, and 7.5% of the participants, respectively. Multiple regression analysis showed that moderate and complete nasopharyngeal obliteration was associated with an increase in the mean total apnea-hypopnea index by 109% (P = .0002) and 185% (P = .001), respectively, when compared with children without nasopharyngeal obliteration. However, mild nasopharyngeal obliteration, body mass index z-score, age, sex, and race were not significantly associated with an increase in the total apnea-hypopnea index. STN-XR was useful in assessing recurrent/residual adenoid tissue hypertrophy in children with OSA and a history of adenotonsillectomy. Moderate and complete nasopharyngeal obliteration were associated with significantly increased apnea-hypopnea index. Pediatric sleep physicians may consider STN-XR in the evaluation of children with OSA and previous history of adenotonsillectomy. Senthilvel E, Nguyen QL, Gunaratnam B, Feygin YB, Palani R, El-Kersh K. Role of neck radiography in assessing recurrent/residual adenoid hypertrophy in children with OSA and history of adenotonsillectomy: a sleep physician perspective. J Clin Sleep Med. 2023;19(6):1027-1033.

PS-R01-6: SUCCESSFUL ANTIHYPERTENSIVE TREATMENT USING SACUBITRIL/VALSARTAN ALONE IN A PATIENT WITH OBSTRUCTIVE SLEEP APNEA SYNDROME

Obstructive sleep apnea syndrome (O-SAS) is one of the emerging non-communicable health hazards with high rates of morbidity and mortality. O-SAS is known to induce excessive activity of sympathetic nervous system and result in secondary hypertension. Although continuous positive airway pressure (CPAP) is the first line therapy for O-SAS, its poor adherence induces resistant hypertension. Sacubitril/valsartan has a sympatho-inhibitory effect and may contribute to antihypertensive therapy in patients with O-SAS. We present a successful case of a 39-year-old male with O-SAS using sacubitril/valsartan alone. He visited our clinic with severe hypertension noted during a routine health checkup. He was a heavy drinker, resulted in high body mass index. His family members worried about his loud snoring and witnessed apnea during sleep. The polysomnography showed a markedly increased apnea-hypopnea index of 37, which led to a diagnosis of severe obstructive sleep apnea. At first, we started treatment with CPAP and azilsartan, but he stopped CPAP due to excessive drinking. Then, we switched azilsartan to sacubitril/valsartan, and succeeded in improving his blood pressure. This case indicates that sacubitril/valsartan may be an effective therapy for uncontrollable hypertenstion due to O-SAS even without CPAP.

Accumulating Comorbidities May Promote Increasing Severity of Obstructive Sleep Apnea with Aging in Males but Not in Females.

Evidence suggests an increasing apnea-hypopnea index (AHI) with aging. However, the effect of aging on sleep-related metrics, especially AHI, has been less frequently investigated within different gender-specific subpopulations by taking prominent confounding factors, e.g., obstructive sleep apnea (OSA)-related comorbidities and body mass index (BMI) into account. Therefore, we retrospectively analyzed 186 first-time polysomnographic (PSG) recordings and medical files of all patients presented to a tertiary university sleep center during a 1-year period. Six groups were formed based on age (over vs. under 55 years) and gender: PSG-related parameters (AHI, apnea-index, and hypopnea-index) were significantly higher in the older mixed-gender cohort (p = 0.0001, p = 0.0011, and p = 0.0015, respectively), and the older female cohort (p = 0.0005, p = 0.0027, and p = 0.001, respectively). Within the older male cohort, the AHI and apnea-index were significantly higher (p = 0.0067, and p = 0.0135, respectively). Inter-group comparison of the BMI showed no significant difference in any subpopulation. Within the older male cohort there were significantly more patients with arterial hypertension, diabetes mellitus, cardiovascular diseases, and chronic mental health disorders (p &lt; 0.0001, p = 0.001, p = 0.0181, and p = 0.0454, respectively). Contrarily, within the female subpopulation there were no significant differences for the aforementioned comorbidities. In conclusion, all investigated sleep PSG-parameters increased among the older subpopulations. We suggest that Osa severity may increase with age due to the increasing accumulation of comorbidities in males, but not in females.

Symptoms of sleep disordered breathing: Association with the apnea-hypopnea index and somatic arousal

We investigated the association of typical symptoms of obstructive sleep apnea with a measure of daytime somatic arousal and with the apnea-hypopnea index. We extended the finding of an association between sleepiness, fatigue and somatic arousal previously reported in a US sleep apnea population to a German sleep apnea population (n = 374) and to other typical sleep apnea symptoms, insomnia, anxiety, daytime alertness and non-restorative sleep.Somatic arousal was measured using the body sensation questionnaire (BSQ). Correlations of apnea-hypopnea index and BSQ were computed with values of polysomnographic variables derived from overnight sleep studies and with severity of OSA symptoms.Apnea-hypopnea index and BSQ scores showed only a small negative correlation with each other; each correlated independently with the Epworth Sleepiness Scale score. Controlling for BSQ score, the apnea-hypopnea index was found to affect sleepiness only when it exceeded 50/h.Severity of all other sleep apnea symptoms did not increase with increasing apnea-hypopnea index. In contrast, severity of all symptoms of sleep apnea increased consistently with increasing BSQ scores. Thus, autonomic stress associated with obstructive sleep apnea may be the driving force behind sleep apnea symptoms rather than the sleep fragmentation associated with obstructive sleep apnea severity (apnea-hypopnea index).These findings support previously reported correlations by Gold and associates between the levels of somatic arousal, sleepiness and fatigue. Using the apnea-hypopnea index and BSQ together renders a more comprehensive assessment of sleep apnea than apnea-hypopnea index alone, which appears to impact only on sleepiness and only when it exceeds 50/h. More work is needed to elucidate the source of the chronic stress, which appears to arise endogenously in affected individuals, likely as a function of sleep disordered breathing, such as snoring/inspiratory flow limitation.

Association between obstructive sleep apnea (OSA) and atrial fibrillation (AF): A dose-response meta-analysis.

Background:Refractory hypoxemia episodes are characteristic of obstructive sleep apnea (OSA). Patients with OSA suffer from oxidative stress in all systems. Atrial fibrillation (AF) is a type of arrhythmia that may be induced by OSA. In this study, we explored the dose-response relationship between OSA and AF. Our research provides the basis for a novel approach to AF prevention.Methods:We screened four databases (PubMed, Embase, the Cochrane Library, and Web of Science) for observational studies on OSA and AF. Studies were collected from database establishment to November 2020. We performed a traditional subgroup meta-analysis. Linear and spline dose-response models were applied to assess the association between the apnea-hypopnea index, an indicator of OSA severity, and the risk of AF. Review Manager version 5.3 software and Stata 16.0 were used for the analysis.Results:Sixteen observational studies were included in the study. We excluded a study from the conventional meta-analysis. In the subgroup analysis, the odds ratios for new onset AF for no obvious reason, new onset AF after surgical operations, such as coronary artery bypass grafting, and AF after ablation treatment were 1.71 (95% CI 1.37–2.13, P < .05), 2.65 (95% CI 2.32–3.01, P < .05), and 2.93 (95% CI 2.47–3.49, P < .05), respectively. Linear dose-response meta-analysis results revealed that the risk of AF increased with increasing apnea-hypopnea index value.Conclusion:Through dose-response meta-analysis, we found a potential dose-response relationship between OSA severity and the risk of AF. This relationship should be considered in interventions aimed at AF prevention in the future.

Isovolemic hemodilution in chronic mountain sickness acutely worsens nocturnal oxygenation and sleep apnea severity.

Chronic mountain sickness (CMS) is commonly observed among Andean and other highland populations. Sleep-disordered breathing (SDB) is highly prevalent at high altitude, and SDB and nocturnal hypoxemia have been observed in CMS. Phlebotomy is commonly performed to treat CMS, but it is unknown whether reducing hematocrit improves SDB. We hypothesized that isovolemic hemodilution (IVHD) in CMS would reduce SBD severity and improve sleep efficiency. Six participants with CMS and 8 without CMS, all residents of Cerro de Pasco, Peru (altitude 4340 m), completed baseline nocturnal sleep studies. CMS participants then underwent IVHD, and nocturnal sleep studies were repeated 24-48 hours after IVHD. We analyzed sleep apnea severity, nocturnal oxygenation, and sleep quality in those with CMS relative to those without CMS, and the effects of IVHD in CMS participants. Participants with CMS did not have altered sleep architecture, sleep apnea severity, or nocturnal oxygenation relative to non-CMS participants. However, IVHD in CMS increased apnea-hypopnea index (40.9 ± 6.9 events/h to 61.5 ± 7.7 events/h, P = .009). IVHD increased oxyhemoglobin desaturation index (P = .008) and the percentage of sleep time spent with oxyhemoglobin saturation at or below 80% (P = .012). There was no effect of IVHD on sleep efficiency, arousal index, or sleep staging. In this cohort, CMS was not associated with worsened SDB or changes in sleep architecture. IVHD, a putative therapeutic option for participants with CMS, appears to worsen nocturnal oxygenation and SDB within 48 hours post-IVHD. Sanchez-Azofra A, Villafuerte FC, DeYoung PN, etal. Isovolemic hemodilution in chronic mountain sickness acutely worsens nocturnal oxygenation and sleep apnea severity. J Clin Sleep Med. 2022;18(10):2423-2432.

Adult Female Sleep During Hypoxic Bed Rest.

PurposeHypobaric hypoxic habitats are currently being touted as a potential solution to minimise decompression procedures in preparation for extra vehicular activities during future space missions. Since astronauts will live in hypoxic environments for the duration of such missions, the present study sought to elucidate the separate and combined effects of inactivity [simulated with the experimental bed rest (BR) model] and hypoxia on sleep characteristics in women.MethodsTwelve women (Age = 27 ± 3 year) took part in three 10-day interventions, in a repeated measures cross-over counterbalanced design: (1) normobaric normoxic BR (NBR), (2) normobaric hypoxic BR (HBR; simulated altitude of 4,000 m), and (3) normobaric hypoxic ambulatory (HAMB; 4,000 m) confinement, during which sleep was assessed on night 1 and night 10 with polysomnography. In addition, one baseline sleep assessment was performed. This baseline assessment, although lacking a confinement aspect, was included statistically as a fourth comparison (i.e., pseudo normobaric normoxic ambulatory; pNAMB) in the present study.ResultsHypoxia decreased sleep efficiency (p = 0.019), increased N1% sleep (p = 0.030), decreased N3 sleep duration (p = 0.003), and increased apnea hypopnea index (p < 0.001). BR impaired sleep maintenance, efficiency, and architecture [e.g., N2% sleep increased (p = 0.033)]. Specifically, for N3% sleep, the effects of partial pressure of oxygen and activity interacted. Hypoxia decreased N3% sleep both when active (pNAMB vs HAMB; p < 0.001) and inactive (NBR vs HBR; p = 0.021), however, this decrease was attenuated in the inactive state (–3.8%) compared to the active state (–10.2%).ConclusionA 10-day exposure to hypoxia and BR negatively impacted sleep on multiple levels as in macrostructure, microstructure and respiratory functioning. Interestingly, hypoxia appeared to have less adverse effects on sleep macrostructure while the participants were inactive (bed ridden) compared to when ambulatory. Data were missing to some extent (i.e., 20.8%). Therefore, multiple imputation was used, and our results should be considered as exploratory.

Combined Association Between ADIPOQ, PPARG, and TNF Genes Variants and Obstructive Sleep Apnea in Chinese Han Population.

PurposeObstructive sleep apnea (OSA) is a common chronic polygenic disease. Multiple genetic markers associated with OSA have been identified by genome-wide association studies. Here, we aimed to construct a polygenic risk score (PRS) and examine the association with the presence of OSA in a Chinese Han Population.Patients and MethodsThis study included 1057 individuals who were genotyped for nine susceptibility loci from three genes (ADIPOQ, PPARG, and TNF), from which each individual’s PRS was calculated by summing the number of risk alleles. The associations between PRS and OSA were determined by logistic regression analyses. Model discrimination was assessed by a receiver operating characteristic (ROC) curve using bootstrapping with 1000 resamples.ResultsThe subjects included 874 with OSA and 183 controls. A higher PRS was associated with an increased apnea-hypopnea index (AHI). The PRS was an important risk factor for the development of OSA (OR = 1.237 per SD, P = 0.030). Subjects with higher PRS had a 2.88-fold (95% CI: 1.393–5.955, P = 0.004) and 5.402-fold (95% CI: 2.311–12.624, P<0.001) greater risk for having OSA and moderate-to-severe OSA, respectively, compared with those with lower genetic risk. More importantly, compared with determination of risk based solely on clinical factors, addition of the PRS increased discriminatory accuracy for both OSA (AUC from 0.75 to 0.78, P = 0.02) and moderate-to-severe OSA (AUC from 0.80 to 0.83, P = 0.02).ConclusionOur study suggests that the PRS is independently associated with AHI and OSA. Combining PRS with conventional risk factors could improve the discrimination of OSA.

Exclusion of EEG-based arousals in wake epochs of polysomnography leads to underestimation of the arousal index.

There is an internal contradiction in current American Academy of Sleep Medicine standards for arousal index (AI) calculation in polysomnography: Arousals in sleep and wake epochs are counted, but only sleep time is used in the denominator. This study aimed to investigate the impact of including arousals scored in wake epochs on the AI. We compared AIs including (AIinc) vs excluding (AIexc) awake-epoch arousals from 100 consecutive polysomnograms conducted for investigation of possible obstructive sleep apnea. To determine the AI that most closely approximated "truth," AIinc and AIexc were compared to an AI calculated from continuous sleep analysis (AIcont) in a 20-polysomnogram subgroup of patients. The median (interquartile range) increase in AIinc was 5.2 events/h (3.5-8.1) vs AIexc (AIinc = 28.0 events/h [18.4-38.9] vs AIexc = 22.9 events/ h [13.1-31.3]), equating to an increase of 25.3% (15.6-40.8). As the AI increased, the difference increased (P < .001), with decreasing sleep efficiency and an increasing apnea-hypopnea index as the strongest predictors of the difference between AIexc and AIinc. The absolute AIexc-AIcont difference (7.7 events/h [5.1-13.6]) was significantly greater than the AIinc-AIcont difference (1.2 events/h [0.6-5.7]; z = -3.099; P = .002). There was a notable increase in AI when we included wake-epoch arousals, particularly in patients with more severe obstructive sleep apnea or reduced sleep efficiency. However, the AI including wake-epoch arousals best matched the "true" continuous sleep-scoring AI. Our study informs clinical and research practice, highlights epoch scoring pitfalls, and supports the current American Academy of Sleep Medicine standard arousal reporting approach for future standards. Wilson DL, Tolson J, Churchward TJ, Melehan K, O'Donoghue FJ, Ruehland WR. Exclusion of EEG-based arousals in wake epochs of polysomnography leads to underestimation of the arousal index. J Clin Sleep Med. 2022;18(5):1385-1393.

Associations of ambient air pollution with overnight changes in body composition and sleep-related parameters

This study aims to investigate the association of air pollution with overnight change in 4body composition and sleep-related parameters. Body composition of 197 subjects in New Taipei city was measured before and after sleep by bioelectric impedance analysis. Air pollutant data were collected from Taiwan Environmental Protection Administration. Sleep parameters were examined by polysomnography. We observed fine particulate matter (PM2.5) decreased arterial oxygen saturation (SaO2) and increased apnea-hypopnea index (AHI); NO2 increased arousal, AHI, and decreased mean SaO2; and O3 inmcreased mean SaO2. We observed 0.99-μg/m3 increase in PM2.5 was associated with 18.8% increase in changes of right arm fat percentage (95% confidence interval (CI): 0.004, 0.375) and 0.011-kg increase in changes of right arm fat mass (95% CI: 0.000, 0.021). 2.45-ppb increase in NO2 was associated with 0.181-kg decrease in changes of muscle mass (95% CI: −0.147, −0.001), 0.192-kg decrease in changes of fat free mass (95% CI: −0.155, −0.001), 21.1% increase in changes of right leg fat percentage (95% CI: 0.012, 0.160), and 21.3% increase in changes of left leg fat percentage (95% CI: 0.006, 0.168). 1.56-ppb increase in O3 was associated with 29.3% decrease in changes of right leg fat percentage (95% CI: −0.363, −0.013), 0.058-kg increase in changes of right leg fat free mass (95% CI: 0.008, 0.066), and 0.059-kg increase in changes of right leg muscle mass (95% CI: 0.010, 0.066). We observed AHI was associated with overnight changes in fat percentage, total fat mass, muscle mass, bone mass, fat free mass, extracellular water, basal metabolic rate, leg fat percentage, leg fat mass, and trunk fat percentage (p < 0.05). In conclusion, exposure to air pollutants was associated with overnight body composition changes and sleep-related parameters. Nocturnal changes in total muscle mass and leg fat percentage likely contribute to the relationship between air pollution and obstructive sleep apnea.

Factors influencing adherence to continuous positive airway pressure treatment in obstructive sleep apnea and mortality associated with treatment failure – a national registry-based cohort study

ObjectivesAdherence to continuous positive airway pressure (CPAP) in patients with obstructive sleep apnea (OSA) is crucial. Our aim was to identify protective and risk factors against the discontinuation of CPAP treatment in patients with OSA and to estimate the mortality risk in those who were non-adherent to CPAP therapy. MethodsThis was a registry-based cohort study from 37 centers across Sweden with OSA patients on CPAP in the Swedevox Swedish national registry between July 2010 and March 2017. ResultsIn 16,425 patients (70.8% men) with complete follow-up data after 1.2 ± 0.8 years the adjusted relative risk ratio (aRRR) for the discontinuation of CPAP was 0.57 (95% confidence interval (CI) 0.50–0.65) for use of humidifier, 0.87 (95% CI 0.82–0.92) for increasing age per 10 years, 0.80 (95% CI 0.77–0.83) for increasing apnea hypopnea index (AHI) per 5 units/hour, and 0.96 (95% CI 0.95–0.97) per increased unit on the Epworth Sleepiness Scale (ESS). Increasing BMI was associated with increased adherence up to BMI 35. Women and patients with hypertension ran an increased risk of discontinuing CPAP treatment, aRRR 1.28 (95% CI 1.12–1.46) and 1.24 (95% CI 1.12–1.42) respectively. The adjusted hazard ratio (HR) for mortality was 1.74 (95% CI 1.32–2.28) among those who did not adhere to CPAP (median follow-up period 2.4 years after the one year adherence evaluation). ConclusionUse of humidifier is associated with greater adherence to CPAP treatment. Other factors predicting adherence are increasing age, more severe OSA and overweight up to BMI 35, whereas female gender and coexisting hypertension are risk factors for discontinuation of CPAP. Failure to adhere to CPAP is associated with increased mortality.

The relationship between sleep and glucagon-like peptide 1 in patients with abnormal glucose tolerance.

Glucagon-like peptide 1 plays a role in glucose regulation. Sleep disturbances (obstructive sleep apnea, insufficient or poor sleep quality) have been shown to adversely affect glucose metabolism. This study aimed to explore the relationship between sleep and glucagon-like peptide 1 regulation in patients with abnormal glucose tolerance. Seventy-one adults with haemoglobin A1c levels between 5.7% and <6.5% and no history of diabetes participated. Habitual sleep duration and efficiency were obtained from 7-day actigraphy recordings. Obstructive sleep apnea was assessed using an overnight home monitor. Glucagon-like peptide 1 levels were measured during a 75-g glucose tolerance. The area under the curve of glucagon-like peptide 1 was calculated. The mean age (SD) was 55.1 (8.3)years and median (interquartile range) haemoglobin A1c was 5.97% (5.86, 6.23). There was no relationship between sleep duration or efficiency and fasting or area under the curve glucagon-like peptide 1. Glucagon-like peptide 1 levels did not differ among those sleeping ≤5.75, >5.75-<6.5 or ≥6.5h per night. Increasing apnea-hypopnea index, an indicator of obstructive sleep apnea severity, correlated with lower area under the curve glucagon-like peptide 1 (B -0.242, P=0.045), but not with fasting glucagon-like peptide 1 (B -0.213, P=0.079). After adjusting for sex, haemoglobin A1c and body mass index, increasing apnea-hypopnea index was negatively associated with having area under the curve glucagon-like peptide 1 in the highest quartile (odds ratio 0.581, P=0.028, 95% CI 0.359, 0.942). This study demonstrated that increasing obstructive sleep apnea severity was associated with lower glucagon-like peptide 1 response to glucose challenge. This could possibly be an additional mechanism by which obstructive sleep apnea affects glucose metabolism. Whether raising glucagon-like peptide 1 levels in patients with abnormal glucose tolerance with more severe obstructive sleep apnea will be beneficial should be explored.

Obstructive sleep apnea exaggerates cognitive dysfunction in stroke patients

BackgroundObstructive sleep apnea (OSA) is very common in stroke survivors. It potentially worsens the cognitive dysfunction and inhibits their functional recovery. However, whether OSA independently damages the cognitive function in stroke patients is unclear. A simple method for evaluating OSA-induced cognitive impairment is also missing. MethodsForty-four stroke patients six weeks after onset and 24 non-stroke patients with snoring were recruited for the polysomnographic study of OSA and sleep architecture. Their cognitive status was evaluated with a validated Chinese version of Cambridge Prospective Memory Test. The relationship between memory deficits and respiratory, sleeping, and dementia-related clinical variables were analyzed with correlation and multiple linear regression tests. ResultsOSA significantly and independently damaged time- and event-based prospective memory in stroke patients, although it had less power than the stroke itself. The impairment of prospective memory was correlated with increased apnea–hypopnea index, decreased minimal and mean levels of peripheral oxygen saturation, and disrupted sleeping continuity (reduced sleep efficiency and increased microarousal index). The further regression analysis identified minimal levels of peripheral oxygen saturation and sleep efficiency to be the two most important predictors for the decreased time-based prospective memory in stroke patients. ConclusionsOSA independently contributes to the cognitive dysfunction in stroke patients, potentially through OSA-caused hypoxemia and sleeping discontinuity. The prospective memory test is a simple but sensitive method to detect OSA-induced cognitive impairment in stroke patients. Proper therapies of OSA might improve the cognitive function and increase the life quality of stroke patients.

AN INTERESTING ETIOLOGY OF VENTRICULAR TACHYCARDIA.

Intermittent hypoxia and ventilatory intermittence due to sleep disorders such as obstructive sleep apnea can lead to cardiac arrhythmia, coronary artery disease, conductance disturbances and cardiac failure. Sub-clinical and overt hypothyroidism is an important physiopathological complex that is linked with cardiovascular risk, alteration of lipidic profile promoting atherogenic mechanisms. The two pathologies combined can exponentially increase the cardiovascular event risk. This case report demonstrates a young patient with obesity and arterial hypertension accusing irregular heart beats. Despite a normal resting ECG and echocardiography the patient presented malignant ventricular arrhythmias revealed on the 24h Holter ECG. The Epworth scale was 20 and the patient presented numerous episodes of hypopnea with an increased apnea-hypopnea index associated with ventricular arrhytmias on the polisomnography. The endocrine profile of the patient revealed a sublinical hypothyroidism that untreated can lead to accelerated atherosclerosis and arrhytmic risk. CPAP treatment alongside the levothyroxine treatment at TSH levels above 10mUI/L have controlled the malignant arrhythmic events without complex antiarrhythmic drugs sustaining the pathogenic contributions of this two pathologies in arrhythmogenesis process.

Occurrence of sleep related breathing disorders in Egyptian patients with tachyarrhythmia without heart failure

Obstructive sleep apnea hypopnea syndrome (OSAHS) has been implicated in the pathogenesis of many cardiovascular diseases. Over the last decade, the association between OSAHS and cardiac rhythm disorders has garnered the attention of cardiologists and researchers from different clinical subspecialties. Aim of the workThe aim of the study was to assess the occurrence of OSAHS in Egyptian patients with tachyarrhythmia, and to describe characteristics of patients with concomitant OSAHS and tachyarrhythmia. MethodsWe enrolled 32 patients with tachyarrhythmia. In addition to standard examination, investigations and echocardiography to exclude possible causes for arrhythmia all patients underwent an over-night sleep study (level III) to diagnose OSAHS. Manual scoring was performed by two specialists according to criteria established by the American Academy of Sleep Medicine 2012. We considered AHI of 15/h as a cutoff point for diagnosing OSAHS. ResultsOf the 32 patients: seventeen had rapid atrial fibrillation (AF), eight had premature ventricular contractions, five had persistent sinus tachycardia and three had paroxysmal supraventricular tachycardia. OSAHS was present in 27 patients (84.4%), three patients of them had obesity hypoventilation also. Dividing OSAHS patients according to the disease severity showed that moderate OSAHS in 29.6% patients, and severe OSAHS in 70.4% patients. Studying characteristics of patients with OSAHS revealed that the mean±SD of neck circumference (NC) was 39.9±2.47cm, BMI was 36.3±9.17kg/m2, Waist/hip ratio was 0.91±0.08, Epworth Sleepiness Scale (ESS) was 10.85±4.5, Mallampati score (MS) was 2.11±0.84, clinical apnea score was 2.8±1.5, and STOP BANG score was 4.03±1.99. Apnea hypopnea index (AHI) was 49.3±33.2, oxygen desaturation index [3%] (ODI) was 39.9±31, mean O2 saturation was 93.6±8.84 and minimal O2 saturation was 7.9±14.49. Nocturnal bradytachyarrhythmia was found in most of patients, the minimal pulse rate during sleep ranges from 22 to 82/min while the maximal pulse rate ranges from 77 to 254/min. Both AHI and ODI were found to be significantly directly correlated with each of BMI, NC, waist/hip ratio, clinical apnea score, STOP BANG score, ESS, MS and mean pulse rate. Linear regression analysis of potential predictors of increased apnea hypopnea index revealed that triglyceride level is the highest predictor followed by NC then BMI. ConclusionsOSAHS is highly prevalent in patients with tachyarrhythmia. High triglyceride, NC and BMI are the most predictors of presence of OSAHS. AF is the most common form of the arrhythmia in patients with OSAHS. Clinical implicationsOSAHS should be considered as part of the workup of patients with tachyarrhythmia. Both clinical apnea score and STOP BANG are good screening questionnaire to choose patients who need sleep study.

Breathing and Snoring Sound Characteristics during Sleep in Adults.

Sound level meter is the gold standard approach for snoring evaluation. Using this approach, it was established that snoring intensity (in dB) is higher for men and is associated with increased apnea-hypopnea index (AHI). In this study, we performed a systematic analysis of breathing and snoring sound characteristics using an algorithm designed to detect and analyze breathing and snoring sounds. The effect of sex, sleep stages, and AHI on snoring characteristics was explored. We consecutively recruited 121 subjects referred for diagnosis of obstructive sleep apnea. A whole night audio signal was recorded using noncontact ambient microphone during polysomnography. A large number (> 290,000) of breathing and snoring (> 50 dB) events were analyzed. Breathing sound events were detected using a signal-processing algorithm that discriminates between breathing and nonbreathing (noise events) sounds. Snoring index (events/h, SI) was 23% higher for men (p = 0.04), and in both sexes SI gradually declined by 50% across sleep time (p < 0.01) independent of AHI. SI was higher in slow wave sleep (p < 0.03) compared to S2 and rapid eye movement sleep; men have higher SI in all sleep stages than women (p < 0.05). Snoring intensity was similar in both genders in all sleep stages and independent of AHI. For both sexes, no correlation was found between AHI and snoring intensity (r = 0.1, p = 0.291). This audio analysis approach enables systematic detection and analysis of breathing and snoring sounds from a full night recording. Snoring intensity is similar in both sexes and was not affected by AHI.

Effect of Yokukansan, a Traditional Herbal Prescription, on Sle ep Disturbances in Patients with Alzheimer's Disease

Objective: Evidence of the effects of Yokukansan (YKS), a traditional herbal medicine, on behavioral and psychological symptoms of dementia (BPSD) has accumulated. As well as BPSD, patients with Alzheimer’s disease (AD) demonstrate poorer sleep quality. Specific sleep disorders such as sleep-disordered breathing and periodic limb movement disorder (PLMD) can be prevalent in the elderly. PLMs are generally considered to produce sleep fragmentation by provoking arousals. This study aimed to examine whether YKS alters polysomnography variables in patients with AD. Methods: Seven patients (3 men and 4 women) with probable AD according to the standard criteria were investigated. Participants were treated with YKS for 4 weeks. The Neuropsychiatric Inventory for the assessment of BPSD, the Mini-Mental State Examination (MMSE) for cognitive function, polysomnography for evaluation of sleep structure and Pittsburgh Sleep Quality Index (PSQI) for subjective sleep quality, and Epworth Sleepiness Scale (ESS) were carried out at baseline and at the end of the treatment. The local institutional review boards approved this study. All patients gave written consent according to institutional guidelines and the tenets of the Declaration of Helsinki. Results: Treatment with YKS resulted in a decreased NPI score, a prolonged total sleep time, a shortened sleep latency, an increased sleep efficiency, and decreased periodic limb movement during sleep. YKS also improved subjective evaluations with PSQI and ESS. Conclusions: YKS was effective for BPSD and sleep disturbances in patients with AD. YKS did not induce daytime somnolence, extrapyramidal signs, or an increased apnea-hypopnea index.