Differences in electroencephalographic spectra during pre-sleep wakefulness, N1, and R sleep between comorbid insomnia and obstructive sleep apnea

PURPOSE

The neuropsychobiological effects of the comorbidity of insomnia and obstructive sleep apnea are not well studied. Our objective was to compare electroencephalographic spectra of patients with comorbid insomnia and sleep apnea syndrome to those of patients with sleep apnea syndrome alone during pre-sleep wakefulness and the N1 and R sleep periods.

METHOD

We performed electroencephalography and polysomnography on 10 patients with comorbid insomnia and sleep apnea and 10 with only sleep apnea. Electroencephalography spectra analysis was performed for absolute power in clinical bands in six derivations.

RESULTS

Compared to sleep apnea patients, comorbid patients had lower sleep efficiency and total sleep time, higher beta-1 power in the left frontal and central derivations during pre-sleep wakefulness, higher delta power in the left frontal and central derivations during the N1 stage, and higher beta-2 power in the left frontal and central, and right central derivations during the R stage.

CONCLUSIONS

Data suggest that patients with insomnia and sleep apnea, compared to patients with only sleep apnea, presented higher left high-frequency rhythms during pre-sleep wakefulness and R sleep stage, and may be for increased emotional and cognitive-related activity, while in stage N1, presented higher left delta power, which suggest some slowing after sleep deprivation.

The impact of continuous positive airway pressure therapy on circulating levels of malondialdehyde: a systematic review and meta-analysis

BACKGROUND

Obstructive sleep apnea (OSA) is a highly prevalent sleep disorder which associated with increased oxidative stress and cardiovascular diseases. Malondialdehyde (MDA) is a reliable marker of lipid peroxidation and is elevated in patients with OSA. Studies reported inconsistent findings on the effect of continuous positive airway pressure (CPAP) therapy on MDA levels. As the study power maybe a reason for the inconsistent findings, we aimed to use meta-analysis to assess effect of CPAP therapy on MDA in patients with OSA.

METHOD

Electronic search was performed to find out studies on the effect of CAPA on MDA levels in OSA patients. Search carried out in databases of PubMed, EMBASE, Scopus, Cochrane library and web of science.

RESULTS

Search resulted in 161 records of which 83 remained after removing duplicated records. Further, 51 articles were removed by title and abstract and 22 records evaluated by full text. Finally 13 articles were included in the intended meta-analysis. Pooled analysis demonstrated that CPAP therapy reduced MDA levels significantly [SMD (-1.51) (95% CI, -2.06 to -0.97) p < 0.05]. Subgroup analyses showed that CPAP therapy was effective in categories of age (≤50 and > 50 years), BMI (≤30 and > 30 kg/m²) and therapy duration (≤12 week and >12 week).

CONCLUSION

the results of the present study demonstrated considerable effect of CPAP therapy on MDA as independent risk factor for cardiovascular diseases and robust marker of lipid peroxidation.

A preliminary examination of brain morphometry in youth with Down syndrome with and without parent-reported sleep difficulties

BACKGROUND

Down syndrome is associated with poor sleep but little is known about its neural correlates.

AIMS

The current research compared brain morphometry in youth with Down syndrome with parent-reported sleep problems (DS-S) to peers with Down syndrome (DS) and typical development (TD) without parent-reported sleep problems matched on age (M = 15.15) and sex ratio (62 % female).

METHODS AND PROCEDURES

Magnetic resonance imaging was completed on a 3 T scanner. Participants were stratified into groups based on parent-report: DS-S (n = 17), DS (n = 9), TD (n = 22). Brain morphometry, processed with the FreeSurfer Image Analysis Suite, was compared across groups. In addition, the co-occurrence of medical conditions in the DS groups was examined.

OUTCOMES AND RESULTS

Youth with DS-S had reduced total, frontal, parietal, and temporal brain volumes relative to DS and TD peers. They also had higher rates of congenital heart defects than the DS-only group; however, this comorbidity did not appear to account for morphometry differences.

CONCLUSIONS AND IMPLICATIONS

Parent-reported sleep problems in DS appear to relate to global and localized volume reductions. These preliminary results have implications for understanding the neural correlates of poor sleep in DS; they also highlight the importance of examining relations between sleep and other medical comorbidities.

Portable diagnosis of sleep apnea with the validation of individual event detection

STUDY OBJECTIVE

To develop an algorithm for improving apnea hypopnea index (AHI) estimation which includes event by event validation and event duration estimation. The algorithm uses breathing sounds, respiratory related movements and blood oxygen saturation (SaO₂).

METHODS

Adults with suspected sleep apnea underwent overnight polysomnography (PSG) at Toronto Rehabilitations Institute. Simultaneously with PSG, breathing sounds and respiratory related movements were recorded over the suprasternal notch using the Patch. The Patch had a microphone and an accelerometer to record respiratory sounds and movement, respectively. First, we calculated the amount of drops in SaO₂ from pulse oximeter. Subsequently, energy of breaths and accelerometer were extracted. Features were normalized, weighted, summed and passed through a threshold to estimate Patch_AHI. Patch_AHI was compared to the AHI obtained from PSG (PSG_AHI). Furthermore, performance of event detection was evaluated using F1-score. Moreover, event duration difference between estimated and PSG-based events was compared.

RESULTS

Data from 69 subjects were investigated. Patch_AHI had high correlation with PSG_AHI (r² = 0.88). Considering a diagnostic AHI cut-off of ≥15, sensitivity and specificity were 91.42 ± 11.92% and 89.29 ± 7.62%, respectively. F1-score for individual event detection increased from 0.22 ± 0.10 for AHI≤5 to 0.72 ± 0.09 for AHI >30. Moreover, event duration difference between estimated events and PSG-based events was 5.33 ± 8.17 sec.

CONCLUSION

Our proposed algorithm had high accuracy in estimating individual respiratory events during sleep. The algorithm can increase reliability of acoustic methods for diagnosis of sleep apnea at home.

Long-term Effect of CPAP Treatment on Cardiovascular Events in Patients With Resistant Hypertension and Sleep Apnea. Data From the HIPARCO-2 Study

BACKGROUND

There is some controversy about the effect of continuous positive airway pressure (CPAP) on the incidence of cardiovascular events (CVE). However, the incidence of CVE among patients with both obstructive sleep apnea (OSA) ans resistant hypertension (HR) has not been evaluated. Our objective was to analyze the long-term effect of CPAP treatment in patients with RH and OSA on the incidence of CVE.

METHODS

Multi-center, observational and prospective study of patients with moderate-severe OSA and RH. All the patients were followed up every 3-6 months and the CVE incidence was measured. Patients adherent to CPAP (at least 4h/day) were compared with those with not adherent or those who had not been prescribed CPAP.

RESULTS

Valid data were obtained from 163 patients with 64 CVE incidents. Treatment with CPAP was offered to 82%. After 58 months of follow-up, 58.3% of patients were adherent to CPAP. Patients not adherent to CPAP presented a non-significant increase in the total CVE incidence (HR:1.6; 95%CI: 0.96-2.7; p=0.07). A sensitivity analysis showed that patients not adherent to CPAP had a significant increase in the incidence of cerebrovascular events (HR: 3.1; CI95%: 1.07-15.1; p=0.041) and hypertensive crises (HR: 5.1; CI95%: 2.2-11.6; p=0.006), but the trend went in the opposite direction with respect to coronary events (HR: 0.22; CI95%: 0.05-1.02; p=0.053).

CONCLUSIONS

In patients with RH and moderate-severe OSA, an uneffective treatment with CPAP showed a trend toward an increase in the incidence of CVE (particularly neurovascular events and hypertensive crises) without any changes with respect to coronary events.

Reliability of Home Nocturnal Oximetry in the Diagnosis of Overlap Syndrome in COPD

BACKGROUND

Chronic obstructive pulmonary disease (COPD) and sleep apnea are common conditions and often coexist. The proper diagnosis of sleep apnea may affect the management and outcome of patients with COPD.

OBJECTIVE

To determine the accuracy of home nocturnal oximetry to distinguish between nocturnal oxygen desaturation related to COPD alone or to sleep apnea in patients with moderate-to-severe COPD who have significant nocturnal hypoxemia with cyclical changes in saturation.

METHODS

This study involved a comparison of home nocturnal oximetry and laboratory-based polysomnography (PSG) in patients with moderate-to-severe COPD considered for inclusion in a trial of nocturnal oxygen therapy. All of the patients had significant nocturnal oxygen desaturation (defined as ≥30% of the recording time with a transcutaneous arterial oxygen saturation <90%) with cyclical changes in saturation suggestive of sleep apnea.

RESULTS

PSG was obtained in 90 patients; 45 patients (mean age = 68 years, SD = 8; 71% men; mean forced expiratory volume in 1 s [FEV1] = 50.6% predicted value, SD = 18.6%; data from 41 patients) fulfilled the criteria for sleep apnea (mean apnea-hypopnea index = 32.6 events/h, SD = 19.9) and 45 patients (mean age = 69 years, SD = 8; 87% men; mean FEV1 predicted value 44.6%, SD = 15%) did not (mean apnea-hypopnea index = 5.5 events/h, SD = 3.8). None of the patients' characteristics (including demographic, anthropometric, and physiologic measures) predicted the diagnosis of sleep apnea according to PSG results.

CONCLUSION

The diagnosis of sleep apnea in patients with moderate to severe COPD cannot rely on nocturnal oximetry alone, even when typical cyclical changes in saturation are seen on oximetry tracing. When suspecting an overlap syndrome, a full-night, in-laboratory PSG should be obtained.

Feasibility of Online Haemodiafiltration in Sleep Apnoea: A Randomized Crossover Study

BACKGROUND

Sleep apnoea is prevalent in dialysis patients. Previous studies identified excessive inflammation in -patients with sleep apnoea. Online haemodiafiltration -(OL-HDF) may reduce systematic inflammation through better clearance of middle molecules. We aimed to determine the feasibility of OL-HDF in sleep apnoea management.

METHODS

Eligible dialysis patients were screened for risk of sleep apnoea by nocturnal oximetry followed by a diagnostic sleep study to assess apnoea-hypopnea index (AHI). Patients with AHI ≥15/h were invited to a randomized crossover trial. The intervention was 2-month high-flux haemodialysis (HF-HD) followed by 2-month OL-HDF or vice versa with 1-month washout via HF-HD. Feasibility was assessed by patient recruitment and the primary outcome, severity of sleep apnoea (AHI). Secondary outcomes were pro-inflammatory cytokines, patient-reported daytime sleepiness, quality of sleep and health-related quality of life.

RESULTS

Of 65 participants at risk of sleep apnoea, only 15 were consented and randomized (mean age 70 years, 80% male, mean AHI 42.2/h). AHI was not statistically different between OL-HDF versus HF-HD (55.6/h vs. 48.3/h, p = 0.134); however, when sleep apnoea was stratified into obstructive and central apnoea, patients had less obstructive episodes after treated by OL-HDF (23.2/h vs. 18.6/h, p = 0.178); a sensitivity analysis was performed excluding outliers, and the treatment effect for obstructive episodes was found to be statistically significant (11.1 vs. 18.2/h, p = 0.019). Pro-inflammatory biomarkers and patient-reported outcomes were similar between OL-HDF and HF-HD.

CONCLUSION

Patient recruitment was a major challenge in this feasibility study. OL-HDF may reduce obstructive sleep apnoea; however, the result needs to be confirmed by larger studies.

Incidence and predictors of adherence to sleep apnea treatment in rehabilitation inpatients with acquired brain injury

OBJECTIVE

The purpose of this study was to describe incidence and assess predictors of adherence to Positive Airway Pressure (PAP) therapy for Obstructive Sleep Apnea (OSA) in persons with acquired brain injury (ABI).

METHODS

A 2012-2015 retrospective analysis of consecutive ABI patients admitted for neurorehabilitation, referred for polysomnography (PSG), and prescribed PAP for OSA. Univariable linear regressions were conducted to examine predictors of average hours of nightly PAP use. Univariable logistic regressions were conducted to examine predictors of PAP adherence using the conventional clinical definition of ≥4 h per night ≥70% of the time. Persons with traumatic etiology were separately analyzed.

RESULTS

ABI etiology was 51% traumatic, 36% stroke, and 13% other nontraumatic causes. Nearly two-thirds were nonadherent to PAP. For the overall sample, higher average nightly PAP usage was significantly predicted by positive hypertension diagnosis (β = 0.271, p = 0.019). Likewise, greater adherence based on the conventional cutoff was predicted by poorer motor functioning at hospital admission (OR = 0.98, p = 0.001) and lower oxygen saturation nadir (OR = 0.99, p = 0.003). For those with traumatic injuries, greater adherence was predicted by poorer functional status at hospital admission (OR = 0.98, p = 0.010) and positive hypertension diagnosis (OR = 0.16, p = 0.023).

CONCLUSIONS

In this study of hospitalized neurorehabilitation patients with ABI and comorbid OSA, predictors of adherence included lower oxygen saturation, poorer functional status and hypertension diagnosis, perhaps signifying the role of greater severity of illness on treatment adherence. High rates of refusal and nonadherence to frontline PAP therapy for sleep apnea is a concern for persons in recovery form ABI who are at a time of critical neural repair.

Metabolomics, sleepiness, and sleep duration in sleep apnea

PURPOSE

Although the mechanism is unclear, daytime sleepiness, a common sequela of obstructive sleep apnea (OSA), has been found to be correlated with a adverse cardiovascular outcomes. Reviewing metabolomics mechanisms of sleep disturbances and cardiovascular disease may help to explain this correlation.

METHODS

This review examines the current literature on the relationships between sleepiness, sleep duration, and metabolites in sleep apnea.

RESULTS

Although there is a lack of comprehensive literature in this emerging area, existing studies point to a variety of metabolites in different pathways that are associated with sleepiness and sleep duration.

CONCLUSION

Advancing metabolomics research in sleep apnea will guide symptom research and provide alternate and novel opportunities for effective treatment for patients with OSA.

Heightened risk of early vocal fold motion impairment onset and dysphagia in the parkinsonian variant of multiple system atrophy: a comparative study

Objective

We compared differences in frequency and timing of onset of the following clinical events between the cerebellar and parkinsonian variants of multiple system atrophy (MSA-C and MSA-P, respectively): type of operation including tracheostomy and/or aspiration prevention surgery, vocal fold motion impairment (VFMI), sleep apnea (SA), introduction of mechanical ventilation (MV), and dysphagia. The risks of these events cooccurring with either MSA-C or MSA-P were compared.

Methods

We retrospectively assessed clinical outcomes only of patients with MSA who presented at the Department of Otolaryngology of the University of Tokyo Hospital between 2008 and 2018. The proportion and timing of onset events between MSA-C and MSA-P and risks of onset were compared using chi-square tests and Cox proportional hazard models adjusted for age, sex, and disease severity, respectively.

Results

We identified 113 patients (median age: 60 years, 72 men [64%]). The frequency and timing of VFMI, SA, MV, dysphagia, and surgeries were 55 patients (49%) and 76 (95% CI 61–91) months after MSA onset, 85 (75%) and 41 (32–50), 36 (32%) and 100 (73–127), 77 (68%) and 43 (36–50), and 25 (22%) and 102 (84–120), respectively. Twenty-seven patients (24%) had MSA-P and higher risk of VFMI (p < .001), SA (p = .030), and dysphagia (p = .017) than did patients with MSA-C.

Conclusion

While MSA-P is less common, it may involve heightened risk of VFMI and dysphagia early onset. Thus, careful follow-up for VFMI, SA, and dysphagia may be needed for these patients.

Criteria for Rating Diagnostic Accuracy Studies

Class II.

•

The onset of vocal fold motion impairment varies in multiple system atrophy types

•

The sleep-apnea onset is relatively early in parkinsonian multiple system atrophy

•

The onset of dysphagia is relatively early in parkinsonian multiple system atrophy

•

Respiratory clinical events are more common in parkinsonian multiple system atrophy

Development and validation of a Chinese version of the Sleep Apnea Quality of Life Index

OBJECTIVE

A Chinese version of the Sleep Apnea Quality of Life Index (SAQLI) for patients with obstructive sleep apnea (OSA) undergoing treatment with continuous positive airway pressure (CPAP) was developed and validated. No Chinese versions of the SAQLI have been previously validated.

METHODS

A convenience sample of 78 patients with OSA who received CPAP therapy at a Taiwanese teaching hospital was enrolled. The SAQLI is organized into four domains: daily functioning, social interactions, emotional functioning, and symptoms. This study evaluated the equivalence (forward translation and back translation), validity, and reliability of a Chinese version of the SAQLI.

RESULTS

The content validity index (CVI) values of the daily functioning, social interactions, emotional functioning, and symptom domains were .93, .93, .96, and 1.00, respectively. Construct validity of one factor was generated by exploratory factor analysis, and the factor explained the following: (A) daily functioning 54%, (B) social interactions 59%, (C) emotional functioning 64%, and (D) symptoms 75% of total explained variance. The Cronbach's α internal consistency values for the daily functioning, social interactions, emotional functioning, and symptom domains were 0.68, 0.94, 0.93, and 0.92, respectively. The repeatability of the SAQLI at 7 days and 30 days after the first administration showed reliability coefficients of .94 and .93 (p = 0.001), respectively.

CONCLUSIONS

The results indicate that the Chinese version of the SAQLI has good reliability and validity, as well as refined indicators for assessing the tool's accuracy. Clinicians may thus use the scale to examine the quality of life in Chinese-speaking patients with OSA undergoing CPAP therapy.

Effect of Ultrafiltration on Sleep Apnea and Cardiac Function in End-Stage Renal Disease

RATIONALE

End-stage renal disease (ESRD) patients have high annual mortality mainly due to cardiovascular causes. The acute effects of obstructive and central sleep apnea on cardiac function in ESRD patients have not been determined. We therefore tested, in patients with ESRD, the hypotheses that (1) sleep apnea induces deterioration in cardiac function overnight and (2) attenuation of sleep apnea severity by ultrafiltration (UF) attenuates this deterioration.

METHODS

At baseline, ESRD patients, on conventional hemodialysis, with left ventricular ejection fraction (LVEF) >45% had polysomnography (PSG) performed on a non-dialysis day to determine the apnea-hypopnea index (AHI). Echocardiography was performed at the bedside, before and after sleep. Isovolumetric contraction time divided by left ventricular ejection time (IVCT/ET) and isovolumetric relaxation time divided by ET (IVRT/ET) were measured by tissue doppler imaging. The myocardial performance index (MPI), a composite of systolic and diastolic function was also calculated. One week later, subjects with sleep apnea (AHI ≥15) had fluid removed by UF, followed by repeat PSG and echocardiography. -Results: Fifteen subjects had baseline measurements, of which 7 had an AHI <15 (no-sleep-apnea group) and 8 had an AHI ≥15 (sleep-apnea group). At baseline, there was no overnight change in the LVEF in either the no-sleep-apnea group or the sleep-apnea group. In the no-sleep-apnea group, there was also no overnight change in MPI, IVCT/ET and IVRT/ET. However, in the sleep-apnea group there were overnight increases in MPI, IVCT/ET and IVRT/ET (p = 0.008, 0.007 and 0.031, respectively), indicating deterioration in systolic and diastolic function. Following fluid removal by UF in the sleep-apnea group, the AHI decreased by 48.7% (p = 0.012) and overnight increases in MPI, IVCT/ET and IVRT/ET observed at baseline were abolished.

CONCLUSIONS

In ESRD, cardiac function deteriorates overnight in those with sleep apnea, but not in those without sleep apnea. This overnight deterioration in the sleep-apnea group may be at least partially due to sleep apnea, since attenuation of sleep apnea by UF was accompanied by elimination of this deleterious overnight effect.

Acute stroke and TIA patients have specific polygraphic features of obstructive sleep apnea

Purpose

Obstructive sleep apnea (OSA) is associated with increased risk for stroke, which is known to further impair respiratory functions. However, it is unknown whether the type and severity of respiratory events are linked to stroke or transient ischemic attack (TIA). Thus, we investigate whether the characteristics of individual respiratory events differ between patients experiencing TIA or acute ischemic stroke and matched patients with clinically suspected sleep-disordered breathing.

Methods

Polygraphic data of 77 in-patients with acute ischemic stroke (n = 49) or TIA (n = 28) were compared to age, gender, and BMI-matched patients with suspected sleep-disordered breathing and no cerebrovascular disease. Along with conventional diagnostic parameters (e.g., apnea-hypopnea index), durations and severities of individual apneas, hypopneas and desaturations were compared between the groups separately for ischemic stroke and TIA patients.

Results

Stroke and TIA patients had significantly shorter apneas and hypopneas (p < 0.001) compared to matched reference patients. Furthermore, stroke patients had more central apnea events (p = 0.007) and a trend for higher apnea/hypopnea number ratios (p = 0.091). The prevalence of OSA (apnea-hypopnea index ≥ 5) was 90% in acute stroke patients and 79% in transient ischemic attack patients.

Conclusion

Stroke patients had different characteristics of respiratory events, i.e., their polygraphic phenotype of OSA differs compared to matched reference patients. The observed differences in polygraphic features might indicate that stroke and TIA patients suffer from OSA phenotype recently associated with increased cardiovascular mortality. Therefore, optimal diagnostics and treatment require routine OSA screening in patients with acute cerebrovascular disease, even without previous suspicion of OSA.

Electronic supplementary material

The online version of this article (10.1007/s11325-019-02010-2) contains supplementary material, which is available to authorized users.

Evaluation of Nocturnal Respiratory Complaints in Pregnant Women

Snoring during pregnancy increases the risk of low Apgar score and low birth weight of newborns. Snoring women are twice as likely to be diagnosed as having preeclampsia when compared to non-snoring ones. Snoring may also be linked to, albeit it is not a prerequisite for, apneic events at sleep. The aim of this survey-type study was to evaluate the occurrence and severity of nocturnal respiratory complaints in a group of 312 pregnant women. Problems associated with snoring and other nasopharyngeal symptoms were reported by 60% of women. Complaints were more frequent in patients with a higher body mass index. The symptoms were significantly more frequent in the group of snorers. The results of this study suggest a pattern of basic features in pregnancy, such as snoring, overweight, and upper airway symptoms, which all ought to direct attention of care givers to the diagnostics of sleep-related breathing disorders. The early diagnosis would enable to undertake the measures to prevent preterm labor and to avoid postpartum complications in both mother and newborn.

Polysomnography outcomes of sleep endoscopy-directed intervention in surgically naïve children at risk for persistent obstructive sleep apnea

PURPOSE

Drug-induced sleep endoscopy (DISE) is useful in children with obstructive sleep apnea (OSA) that persists after adenotonsillectomy (AT), but its utility in surgically naïve children is unclear. We report polysomnography outcomes of surgically naïve children who underwent DISE-directed intervention because they were considered high risk for persistent OSA after adenotonsillectomy.

METHODS

This study is a case series of 62 surgically naïve children with OSA who were considered high risk for persistence after AT and underwent DISE-directed intervention with pre- and postoperative polysomnography between 2012 and 2016. Analysis was performed with the paired t test.

RESULTS

Children were on average 5.9 (± 5.5, 0.2-18.6) years old at the time of surgery, 68% male, 18% obese, and 60% white. Thirty-eight percent had a syndromic diagnosis: 19% trisomy 21, 11% hypotonic neuromuscular disorder, and 8% craniofacial condition. The remaining 62% were non-syndromic but underwent DISE because they had at least one risk factor for OSA persistence after AT (age > 7 years, black race, 1+ tonsils, obesity, and/or severe OSA). Forty-two percent underwent AT, while 58% underwent treatment other than AT, including 18% who had multilevel surgery. Children improved significantly in 4 out of 5 polysomnography parameters tested, including obstructive apnea-hypopnea index (oAHI; 22.2 to 7.2, p < 0.01) and oxygen nadir (82 to 87, p < 0.01). Thirty-eight (61%) had a postoperative oAHI < 5; 16 (21%) had a postoperative oAHI < 2.

CONCLUSION

DISE resulted in intervention other than AT in 58% of surgically naïve children at high risk for persistent OSA after AT. DISE-directed intervention resulted in significant mean improvement in postoperative OSA.

The novel indicators of moderate to severe sleep apnea: fibrinogen to albumin ratio vs. CRP to albumin ratio

PURPOSE

This study aimed at investigating the association of severity of obstructive sleep apnea with the markers of inflammation as fibrinogen to albumin ratio and C-reactive protein to albumin ratio.

METHODS

We included 126 patients admitted to sleep disorders outpatient clinic. We constituted four groups by reference to the apnea-hypopnea index (mild-moderate-severe sleep apnea and control group). We investigated the difference of white blood cell, fibrinogen to albumin ratio, C-reactive protein to albumin ratio, neutrophil to lymphocyte ratio, platelet to lymphocyte ratio, and hemoglobin among the groups.

RESULTS

Neutrophil to lymphocyte ratio, platelet to lymphocyte ratio, and hemoglobin did not significantly differ among four groups (p = 0.39, p = 0.06, and p = 0.31, respectively). A significant difference of fibrinogen to albumin ratio and C-reactive protein to albumin ratio was evident among four groups (p < 0.001). Fibrinogen to albumin ratio and C-reactive protein to albumin ratio did not significantly differ between the mild sleep apnea and control groups (p = 0.65, and p = 0.85, respectively), but were significantly greater in moderate sleep apnea group compared with the control group (p < 0.001 and p = 0.001, respectively). Also, fibrinogen to albumin ratio and C-reactive protein to albumin ratio were significantly greater in the severe sleep apnea group compared with the control group (p < 0.001). Fibrinogen to albumin ratio and C-reactive protein to albumin ratio did not significantly differ between the severe sleep apnea and moderate sleep apnea groups (p = 0.49, and p = 0.58, respectively).

CONCLUSION

Higher fibrinogen to albumin ratio and C-reactive protein to albumin ratio may be predictive of inflammation in patients with moderate-to-severe sleep apnea.

Electrical stimulation of the whole hypoglossal nerve in patients with obstructive sleep apnea

PURPOSE

Electrical stimulation of the whole hypoglossal nerve (HGp-ES) has been demonstrated to enlarge the pharynx and improve pharyngeal stability and patency to airflow in all animals studied, but not in humans. The present study was undertaken to better understand the effect of HGp-ES on the human pharynx.

METHODS

Eight patients with obstructive sleep apnea who had implanted stimulators with electrodes positioned proximally on the main truck of the hypoglossus were studied under propofol sedation. Pharyngoscopy and air flow measurements at multiple levels of continuous positive airway pressure (CPAP) were performed before and during Hgp-ES.

RESULTS

HGp-ES that activates both tongue protrusors and retractors narrowed the pharyngeal lumen at the site of collapse (velopharynx in all subjects) from 1.38 ± 0.79 to 0.75 ± 0.44 cm², p < 0.05 (measured at mid-range of CPAP levels) and lowered airflow (from 8.88 ± 2.08 to 6.69 ± 3.51 l/min, p < 0.05). Changes in critical pressure (Pcrit) and velopharyngeal compliance were not significant, but oropharyngeal compliance decreased (from 0.43 ± 0.18 to 0.32 ± 0.13 cm²/cmH2O, p < 0.05). No correlation was found between the pattern of change in luminal shape (determined as the ratio of a-p vs. lateral diameter when lowering CPAP) or changes in cross-sectional area and airflow during Hgp-ES.

CONCLUSIONS

Our findings indicate that human retractors dominate when stimulated together with the protrusors during HGp-ES. While co-activation of retractors may be beneficial, it should be limited. We speculate that exercises that augment protrusor force may improve the response to hypoglossal stimulation. The exclusion of patients with concentric pharyngeal obstruction should be re-evaluated.

Severe obstructive sleep apnea is associated with circulating microRNAs related to heart failure, myocardial ischemia, and cancer proliferation

PURPOSE

Obstructive sleep apnea (OSA) is associated with multiple comorbid conditions including cardiovascular diseases and cancer. There is a growing interest in exploring biomarkers to understand the related mechanisms and improve the risk stratification of OSA. Circulating microRNAs (miRNAs) are single noncoding strands of nearly 22 nucleotides that posttranscriptionally regulate target gene expression. Our aim was to identify miRNA profiles associated with OSA.

METHODS

We studied 48 male subjects, mostly Caucasian (63%) and overweight, divided by polysomnography into the no OSA control group (n = 6), mild OSA group (n = 12), moderate OSA group (n = 15), and severe OSA group (n = 15). The study groups were matched for age, body mass index (BMI), and body fat composition. miRNA profiles were measured from peripheral whole blood using two steps: (1) microarray analysis comprising more than 2500 miRNAs in a subsample of 12 subjects (three from each group); and (2) validation phase using real-time quantitative polymerase chain reaction (RTqPCR).

RESULTS

The microarray assessment identified 21 differentially expressed miRNAs among the groups. The RT-qPCR assessment showed that miR-1254 and miR-320e presented a gradual increase in expression parallel to OSA severity. Linear regression analysis showed that severe OSA was independently associated with miR-1254 (ß = 68.4; EP = 29.8; p = 0.02) and miR-320e (ß = 76.1; EP = 31.3; p = 0.02).

CONCLUSION

Severe OSA is independently associated with miRNAs that are involved in heart failure (miR-1254), myocardial ischemia/reperfusion (miR-320e), and cell proliferation in some cancer types (miR-1254 and miR-320e). Future investigations addressing whether these miRs may provide prognostic information in OSA are needed.

Circulating P-Selectin Glycoprotein Ligand 1 and P-Selectin Levels in Obstructive Sleep Apnea Patients

Purpose

Obstructive sleep apnea (OSA) is characterized by chronic intermittent hypoxia which induces inflammation in blood vessels leading to the development of cardiovascular comorbidities. Several studies implicated the role of P-selectin in vascular inflammation of OSA. P-selectin glycoprotein ligand 1 (PSGL-1) is the main activator for P-selectin and is involved in immune cell trafficking. However, PSGL-1 has not been analyzed in OSA. The aim of the study was to investigate plasma PSGL-1 and P-selectin levels to have a deeper understanding on their interaction in obstructive sleep apnea.

Methods

Fifty-one untreated patients with OSA and 42 non-OSA controls were recruited. Plasma PSGL-1 levels were determined in evening and morning samples, P-selectin levels were analyzed in morning samples using commercially available ELISA kits. Polysomnography was performed in all participants. OSA was defined by an apnea–hypopnea index ≥ 5/h.

Results

PSGL-1 levels did not differ between controls and OSA patients either in the evening or in the morning. Although, there was no difference between controls (16.9/6.8–40.8 ng/ml) and patients with OSA (19.6/8.4–56.8, p = 0.24), patients with severe OSA had increased plasma P-selectin levels (25.6/8.4–56.8 ng/ml) compared to mild OSA patients (14.1/8.5–35.3 ng/ml, p = 0.006) and controls (p = 0.03).

Conclusions

P-selectin expression relates to disease severity suggesting a pathophysiological role in endothelial cell activation. PSGL-1 levels are unaltered in OSA, suggesting an alternative activation pathway for P-selectin in OSA.

Evaluating pediatric intensive care unit utilization after tonsillectomy

OBJECTIVES

To identify patients at risk for a pediatric intensive care unit (PICU) level intervention after adenotonsillectomy.

STUDY DESIGN

Retrospective cross-sectional study.

SETTING

Tertiary Children's Hospital.

SUBJECTS AND METHODS

Ninety-four patients who were admitted to the PICU after adenotonsillectomy were included. The need for PICU level intervention, defined as high flow oxygen by nasal cannula, positive airway pressure (PAP), heliox, and intubation, was documented. The age, gender, BMI percentile, polysomnography (PSG) data, home PAP use, and accompanying comorbidities of patients who required a PICU level intervention were compared to those who did not.

RESULTS

Of the 94 patients admitted post-adenotonsillectomy to the PICU, most had at least one comorbidity, with obesity being the most common. PICU admission was unplanned in 29 (30.9%) patients. Postoperatively, 25 (26.5%) patients required a PICU level intervention, with PAP being the most common intervention. On chi-square analysis, there was no significant difference in the age, BMI percentile, or PSG parameters of children who required PICU intervention. Significantly more children who used preoperative PAP were started on PAP in PICU (p = 0.018). Only the comorbidity of neuromuscular disorder was associated with PICU intervention (p = 0.04). Using binary logistic regression, the use of home PAP and an oxygen nadir <80% on preoperative PSG were found to be independent predictors of PICU intervention (p = 0.04 and 0.025, respectively).

CONCLUSION

Home PAP use, the presence of a neuromuscular disorder, and an oxygen nadir <80% on preoperative PSG is related to a PICU level intervention.

Effect of obstructive sleep apnea syndrome on glycolipid metabolism and early atherosclerosis in diabetics

OBJECTIVE

To study the changes in glucose and lipid metabolism indexes and the condition of early atherosclerosis in patients with diabetes with and without obstructive sleep apnea syndrome (OSAS).

METHODS

Patients with type 2 diabetes mellitus (DM) aged 32-50 years who did not have significant complications were included. A total of 42 patients with DM with OSAS and 46 patients with DM without OSAS were chosen according to their sleep monitoring indexes. Height and weight were measured, and fasting blood glucose, postprandial blood glucose, endothelin (ET), nitric oxide (NO) and lipid profile were tested. Then, all the subjects were subjected to the pulse wave velocity (PWV) test.

RESULTS

The levels of glycated haemoglobin and triglycerides were significantly higher in patients with DM with OSAS than those in patients with DM without OSAS. ET, NO and PWV changed significantly.

CONCLUSION

Patients with diabetes with OSAS are more likely to have complications related to arteriosclerosis and aggravation of glycolipid metabolism disorder. Early intervention is recommended.

Comorbidities in chronic heart failure: An update from Italian Society of Cardiology (SIC) Working Group on Heart Failure

The increasing number of patients with heart failure HF and comorbidities is due to aging population and increase of life expectancy of patients with cardiovascular disease. Encouraging results derived by recent trials may suggest some comorbidities as new targets for new drugs, highlighting the need for a better understanding of the comorbidities' effects in HF patients and the need of a multidisciplinary approach for the management of chronic HF with comorbidities. We report a brief review about main cardiovascular and non-cardiovascular comorbidities in HF patients in order to update physicians and researchers engaged in the HF research or in "fight against heart failure."

[CME: Nacht-zu-Nacht-Variabilität der obstruktiven Schlafapnoe]

Die aktuellen Leitlinien empfehlen, unkomplizierte Patientinnen und Patienten mit Verdacht auf obstruktive Schlafapnoe (OSA) mittels einer einzigen Schlafuntersuchung zu diagnostizieren. Eine kürzlich veröffentlichte Meta-Analyse konnte hingegen eine ausgeprägte intra-individuelle Variabilität respiratorischer Parameter von Nacht zu Nacht zeigen. Wir präsentieren den Fall eines 76-jährigen Patienten mit Verdacht auf OSA, der innerhalb von 13 Wochen sechs Schlafuntersuchungen unterzogen wurde. Hierbei präsentierte sich eine relevante Variabilität des AHI zwischen 1,1 und 43,1/h. Es konnten keine relevanten Unterschiede betreffend Gewicht, Alkoholkonsum, Medikation und Begleiterkrankungen zwischen den Schlafuntersuchungen festgestellt werden. Aufgrund fehlender subjektiver Wirksamkeit wurde die CPAP-Therapie nach einem Jahr gestoppt. Die ausgeprägte Nacht-zu-Nacht-Variabilität respiratorischer Parameter stellt eine akkurate OSA-Diagnostik mittels einer einzelnen Schlafuntersuchung in Frage.

All roads lead to inflammation: Is maternal immune activation a common culprit behind environmental factors impacting offspring neural control of breathing?

Despite numerous studies investigating how prenatal exposures impact the developing brain, there remains very little known about how these in utero exposures impact the life-sustaining function of breathing. While some exposures such as alcohol and drugs of abuse are well-known to alter respiratory function, few studies have evaluated other common maternal environmental stimuli, such as maternal infection, inhalation of diesel exhaust particles prevalent in urban areas, or obstructive sleep apnea during pregnancy, just to name a few. The goals of this review article are thus to: 1) highlight data on gestational exposures that impair respiratory function, 2) discuss what is known about the potential role of inflammation in the effects of these maternal exposures, and 3) identify less studied but potential in utero exposures that could negatively impact CNS regions important in respiratory motor control, perhaps by impacting maternal or fetal inflammation. We highlight gaps in knowledge, summarize evidence related to the possible contributions of inflammation, and discuss the need for further studies of life-long offspring respiratory function both at baseline and after respiratory challenge.

Sagittal Genioplasty: New Techniques

Introduction

The chin is a reflection of the entire face and, along with the nose, is one of the major determinants of facial profile balance. When it is appropriate in size, shape and position, the chin can enhance the normal harmony and symmetry of the face, even camouflaging less than ideal jaw relationships. Failure to perform a needed genioplasty can jeopardise the end product of many hours of otherwise successful major orthognathic or cosmetic surgery. Genioplasty procedure has been used for many years and has been modified in various ways, despite its original description by Trauner and Obwegeser.

Aim

To overcome the disadvantages of older techniques such as step deformity, less bone contact and more chances of relapse.

Method

Type 1-Esthetic genioplasty: A curvilinear horizontal osteotomy can be performed at lower border as posteriorly as possible. After the osteotomy, the detached segment can be moved as per the requirement. Type 2-Functional genioplasty: A horizontal subapical cut was made through full thickness of the mandible involving the labial and lingual cortex, then vertical cuts were made bicortically and two oblique cuts were made at the end of vertical cuts monocortically.

Conclusion

This modification has various advantages such as more bone contact, no step deformity, less chance of relapse and also most effective treatment for sleep apnoea patients.