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Summary As the chronological age increases, there is a decrease in the telomere length (TL). Associations between TL and age‐related diseases have been described. Since the major pathophysiological factors related to inadequate sleep (including sleep complaints and sleep disorders) contribute to the exacerbation of inflammation and oxidative stress, an association of sleep and TL has been proposed. The aim of this study was to evaluate the association between sleep‐related variables with TL in a longitudinal framework. We used data derived from the EPISONO cohort, which was followed over 8 years. All individuals answered sleep‐related questionnaires, underwent a full‐night polysomnography (PSG), and had their blood collected for DNA extraction. The TL was measured through a quantitative real time polymerase chain reaction. Age, sex, body mass index (BMI), smoking, physical activity status, and the 10 principal components (ancestry estimate) were considered covariables. Of the 1042 individuals in the EPISONO cohort, 68.3% agreed to participate in the follow‐up study (n = 712). Baseline SpO2 (ß = 0.008, p = 0.007), medium SpO2 (ß = 0.013, p = 0.013), and total sleep time <90% (ß = −0.122, p = 0.012) had an effect on TL from the follow‐up. The 8 year TL attrition was inversely associated with total sleep time, sleep efficiency, sleep architecture variables, wake after sleep onset, arousal index, oxygen‐related variables baseline, and the presence of obstructive sleep apnea (OSA). We conclude that individuals with worse sleep quality, alterations in sleep architecture, and OSA had greater TL attrition over the 8 years. Using a longitudinal approach, these findings confirm previous cross‐sectional evidence linking sleep with accelerated biological ageing. [ABSTRACT FROM AUTHOR]

ABSTRACT BACKGROUND: Neck circumference (NC) is a useful anthropometric measure for predicting obstructive sleep apnea (OSA). Ethnicity and sex also influence obesity phenotypes. NC cut-offs for defining OSA have not been established for the Latin American population. OBJECTIVES: To evaluate NC, waist circumference (WC), and body mass index (BMI) as predictors of OSA in the Colombian population and to determine optimal cut-off points. DESIGN AND SETTING: Diagnostic tests were conducted at the Javeriana University, Bogota. METHODS: Adults from three cities in Colombia were included. NC, WC, and BMI were measured, and a polysomnogram provided the reference standard. The discrimination capacity and best cut-off points for diagnosing OSA were calculated. RESULTS: 964 patients were included (57.7% men; median age, 58 years) and 43.4% had OSA. The discrimination capacity of NC was similar for men and women (area under curve, AUC 0.63 versus 0.66, P = 0.39) but better for women under 60 years old (AUC 0.69 versus 0.57, P < 0.05). WC had better discrimination capacity for women (AUC 0.69 versus 0.57, P < 0.001). There were no significant differences in BMI. Optimal NC cut-off points were 36.5 cm for women (sensitivity [S]: 71.7%, specificity [E]: 55.3%) and 41 cm for men (S: 56%, E: 62%); and for WC, 97 cm for women (S: 65%, E: 69%) and 99 cm for men (S: 53%, E: 58%). CONCLUSIONS: NC and WC have moderate discrimination capacities for diagnosing OSA. The cut-off values suggest differences between Latin- and North American as well as Asian populations.

Migraine and sleep disorders are common in the general population, may be associated with each other and often significantly reduce patients’ quality of life. Clinicians and epidemiological studies have long acknowledged a link between these conditions. However, the exact nature of this relationship, its underlying mechanisms and patterns are complex and not fully understood. This publication brings together the latest data on the relationship between migraine and sleep disorders: the biochemical and functional-anatomical background, the mutual influence of these conditions on each other and the typical sleep disturbances in migraine patients (such as insomnia, obstructive sleep apnea, parasomnia, snoring, excessive daytime sleepiness). The paper discusses the hypotheses of pathogenetic relationships based on the studies of the central nervous system’s anatomical and physiological features in people with migraine and sleep disorders. The available data should encourage physicians to evaluate sleep quality in migraineurs and use combination therapy systematically. The therapy of insomnia is reviewed: both nonpharmacological and pharmacological therapies are discussed; the advantages of an integrated approach are discussed, and a brief overview of each group of medications is offered.Lastly, a case study of a patient with chronic migraine and insomnia treated with Doxylamine in combination therapy is presented. Treatment with Doxylamine significantly reduced the incidence of insomnia, probably thereby positively influencing the course of migraine as well.

Ambulatory blood pressure monitoring (ABPM) is recommended for the diagnosis of hypertension in children at high risk, such as children with obesity or obstructive sleep apnea (OSA). Nocturnal hypertension is highly predictive of cardiovascular outcomes. ABPM allows for early detection of nocturnal hypertension in children. Although OSA is the most common sleep disorder associated with hypertension, studies have also shown an increase in cardiovascular risk in adult patients with other sleep disorders; therefore, there is an imperative need to provide early diagnosis in children at high risk. In the present study, we evaluated the feasibility of using ABPM during polysomnography (PSG) in children referred for sleep disordered breathing to the Seattle Children's Hospital Sleep Disorders Center. A total of 41 children aged 7–18 years were included in this study. The ABPM monitor was worn for a mean (SD) of 10.2 (1.5) hr. No significant changes were seen in PSG parameters when ABPM was co‐performed with PSG, including sleep efficiency and arousals. In total, 12 of the 41 patients were identified as having nocturnal hypertension. Our study is important in that it shows that concomitant use of ABPM during PSG can aid in the early identification of nocturnal hypertension in this population. [ABSTRACT FROM AUTHOR]

Purpose: Obstructive sleep apnea syndrome is a clinical sleep disorder defined by total or partial airflow restraint during sleep that results in fragmented sleep and hypoxemia, impacting negatively with cognitive functioning. This review was conducted on studies investigating structural brain alteration and cognitive impairment in obstructive sleep apnea syndrome. Method: We searched on PubMed databases and screening references of included studies and review articles for additional citations. From initial 190 publications, only 17 met search criteria and described the cognitive impairment in obstructive sleep apnea syndrome. Results: Findings showed that patients with this syndrome had worse performance than healthy controls in attention, memory, and executive functions, showing specific neuroanathomical features. Cognitive impairment is also related to the severity of pathology. Treatment could improve certain cognitive aspects. Conclusions: Cognitive deficits seem to be mainly attributable to decreased daytime vigilance and nocturnal hypoxemia. [ABSTRACT FROM AUTHOR]

Introduction: There are many options available to patients who are placed on constant positive airway pressure (CPAP) for obstructive sleep apnea. Despite the success of CPAP in correcting apnea, a significant number of patients have difficulty with the therapy. A large number of those patients who have difficulty stop therapy and are often labeled as "CPAP Failure". Non-sleep specialists may view CPAP therapy as a singular course of treatment, but there are many ways CPAP may be ordered for a patient. Each patient experiences a unique set of options that constitute a unique order set. Methods: In order to demonstrate the magnitude of the possible options, estimates of the number of unique order sets were calculated. The author chose individual order options and the number of selections possible within each option. The calculated sets included a "Generous, Limited and Minimal" number of selections for each option. Calculations were done separately for standard CPAP and for auto-adjusting CPAP. Additional calculations were performed using the number of commercially available masks in the United States. Results: The maximum number of unique order sets was seen using a standard CPAP combined with commercially available masks: 49,152 unique order sets. The fewest number of unique order sets were seen with the auto-adjusting CPAP and the "Minimal" selections: 288 unique order sets. Discussion: There are a large number of unique CPAP orders that a patient may experience. CPAP treatment is not a singular or simple therapy. When evaluating obstructive sleep apnea patients with histories of CPAP failure or prior difficulty with CPAP, paying close attention to the patient's treatment experiences may help explain a significant number of those patients' CPAP therapy problems. [ABSTRACT FROM AUTHOR]

Objective: To investigate how prolonged seizure activity affects cardiorespiratory function and activity of pre‐Bötzinger complex, leading to sudden death. Methods: Urethane‐anesthetized female Long‐Evans rats were implanted with nasal thermocouple; venous and arterial cannulae; and electrodes for electrocardiography (ECG) and hippocampal, cortical, and brainstem recording. Kainic acid injection into the ventral hippocampus induced status epilepticus. Results: Seizures caused hypertension, tachycardia, and tachypnea punctuated by recurrent transient apneas. Salivation increased considerably: in 11 of 12 rats, liquid with alkaline pH consistent with saliva was expelled from the mouth. Most transient apneas were obstructive: nasal airflow ceased, while, in 83%, efforts to breathe persisted as continued rhythmic activity of respiratory pre‐Bötzinger neurons, inspiratory electromyography (EMG), and excursions of the chest wall and abdomen. Blood pressure oscillated in time with respiratory efforts. This pattern also occurred in a minority of cases (16%) of incomplete apnea, but not in rare cases (1%) of transient central apneas. During transient obstructive apneas, the frequency of all inspiratory efforts decreased abruptly by ~30%, suggesting a resetting of the central respiratory rhythm generator. Twenty‐two of thirty‐one rats died, due either to obstructive apnea (12) or central apnea following progressive slowing of respiration (10). Most rats dying of central apnea had experienced several transient obstructive apneas. Negative DC field potential shifts of the brainstem followed the final breath, consistent with previous reports on spreading depolarization in mouse models. Timing suggests that the DC shift is a consequence rather than cause of respiratory collapse. Cardiac activity continued for tens of seconds. Significance: Seizure activity in forebrain induces pronounced autonomic activation and disrupts activity in medullary respiratory centers, resulting in death from either obstructive or central apnea. These results directly inform mechanisms of death in status epilepticus, and indirectly provide clues to mechanisms of sudden unexpected death in epilepsy (SUDEP). [ABSTRACT FROM AUTHOR]

Both Respiratory Flow (RF) and Respiratory Motion (RM) are visible in thermal recordings of infants. Monitoring these two signals usually requires landmark detection for the selection of a region of interest. Other approaches combine respiratory signals coming from both RF and RM, obtaining a Mixed Respiratory (MR) signal. The detection and classification of apneas, particularly common in preterm infants with low birth weight, would benefit from monitoring both RF and RM, or MR, signals. Therefore, we propose in this work an automatic RF pixel detector not based on facial/body landmarks. The method is based on the property of RF pixels in thermal videos, which are in areas with a smooth circular gradient. We defined 5 features combined with the use of a bank of Gabor filters that together allow selection of the RF pixels. The algorithm was tested on thermal recordings of 9 infants amounting to a total of 132 min acquired in a neonatal ward. On average the percentage of correctly identified RF pixels was 84%. Obstructive Apneas (OAs) were simulated as a proof of concept to prove the advantage in monitoring the RF signal compared to the MR signal. The sensitivity in the simulated OA detection improved for the RF signal reaching 73% against the 23% of the MR signal. Overall, the method yielded promising results, although the positioning and number of cameras used could be further optimized for optimal RF visibility.

Abstract Background Obstructive sleep apnea contributes to daytime sleepiness, poor quality of life and increased risk for heart disease and hypertension among women. Continuous positive airway pressure improves sleepiness and quality of life and may reduce health risks but few studies have evaluated predictors of adherence among women. The goal of this study was to evaluate the role of relationship factors in women’s continuous positive airway pressure (CPAP) adherence and change in relationship quality among married/partnered women. Methods Women recently diagnosed with obstructive sleep apnea completed relationship quality, social support questionnaires and spousal involvement interviews. CPAP adherence was collected at 12 weeks. Results Data were available for 16 women. Average CPAP adherence was 3.6 SD = 2.7 h per night. Women with higher reports of social support had higher adherence. None of the unmarried/partnered participants were adherent to the recommendation of CPAP use ≥ 4 h per night at 12 week follow-up. Marital status was not associated with demographic, disease severity or social support measures. Relationship conflict among married/partnered participants was associated with lower adherence. In qualitative surveys, encouragement and support were the two most commonly reported types of partner involvement. Relationship quality did not change between baseline and 3 months. Conclusion Results suggest relationship factors are robust predictors of CPAP adherence among women with obstructive sleep apnea.

Adenotonsillar hypertrophy is a common cause of obstructive sleep apnea in children. Affecting ventilation and sleep architecture, recurrent respiratory obstruction can lead to metabolic, cardiovascular, neurobehavioral and somatic consequences. Purpose. To present the etiology and management of nocturnal and diurnal respiratory disorders in a pre-school patient coming from rural area. Materials and Methods. A female patient aged 4 years and 9 months was assessed by an interdisciplinary team. The evaluation included: case history, physical examination, laboratory tests and specialty consults. Case presentation. The patient presented multiple sleeping disorders (apnea, noisy and difficult breathing, intense snoring, orthopnea, frequent awakening) and diurnal symptoms (hypersomnia, attention deficit, nasal obstruction, diminished appetite, dysphagia, nasal voice). At admission, the clinical examination showed failure to thrive, adenoid face, sternal depression, noisy and difficult mouth breathing, severe substernal and intercostal retractions. Important adenotonsillar hypertrophy (grade IV) was confirmed by otolaryngology examination. Sleep polygraph showed very severe obstructive sleep apnea. Extracapsular tonsillectomy and adenoidectomy were performed under high anesthetic and surgical risk. Intra and postoperative outcome was positive, with the remission of the upper respiratory airway obstruction symptoms. Conclusions. Despite suggestive symptoms the patient presentation was late. Neurobehavioral manifestations and somatic disorders suggest the long-term evolution of upper respiratory airway obstruction. The extreme severity of sleep apnea was revealed by polygraph study. The sleep functional evaluation has contributed decisively to the therapeutic management and the favorable evolution of the case. [ABSTRACT FROM AUTHOR]

Background: Acute laryngospasm sufficient to cause obstructive apnea is a medical emergency that can be difficult to manage within the very short time available for establishing an airway. We have presented substantial evidence that laryngospasm‐based obstructive apnea is the cause of sudden death in epilepsy, and airway management is particularly challenging during seizure activity. Objective: We sought to determine if the transtracheal delivery of a bolus of oxygen or room air below the level of an obstruction to inflate the lungs could be an effective method to prolong the time available for responders seeking to establish a stable airway, and, if so, what could be learned about optimization of delivery parameters from a rat model. Methods: Rats were fitted with a t‐shaped tracheal tube for controlling access to air and for measuring airway pressures. After respiratory arrest from simulated laryngospasm, bolus transtracheal lung inflation with a volume of gas equivalent to half the vital capacity was delivered to the closed respiratory system as the only resuscitation step. Results: Bolus lung inflation was sufficient for resuscitation, improving cardiac function and re‐establishing adequate oxygen status to support life. Inflation steps could be repeated and survival times were approximately 3 times that of non‐inflated lungs. Conclusion: The properties and consequences of bolus lung inflation are described as a foundation for procedures or devices that can be useful in cases of severe laryngospasm and other cases of upper airway obstruction. Level of Evidence: 3 [ABSTRACT FROM AUTHOR]

This review traces the examination of autonomic, cardiovascular, and respiratory derangements associated with seizure activity in the clinical and preclinical literature generally, and in the author’s animal model specifically, and concludes with the author’s views on the potential mechanisms for sudden death in epilepsy (SUDEP). An animal model that employs kainic acid-induced seizures on a background of urethane anesthesia has permitted unprecedented access to the behavior of autonomic, cardiovascular, and respiratory systems during seizure activity. The result is a detailed description of the major causes of death and how this animal model can be used to develop and test preventative and interventional strategies. A critical translational step was taken when the rat data were shown to directly parallel data from definite SUDEP cases in the clinical literature. The reasons why ventricular fibrillation as a cause of death is so rarely reported and tools for verifying that seizure-associated laryngospasm can induce obstructive apnea as a cause of death are discussed in detail. Many details of the specific kinetics of activation of brainstem neurons serving autonomic and respiratory function remain to be elucidated, but the boundary conditions described in this review provide an excellent framework for more focused studies. A number of studies conducted in animal models of seizure activity and in epilepsy patients have contributed information on the autonomic, cardiovascular, and respiratory consequences of seizure activity spreading through hypothalamus and brainstem to the periphery. The result is detailed information on the systemic impact of seizure spread and the development of an understanding of the essential mechanistic features of sudden unexpected death in epilepsy (SUDEP). This review summarizes translation of data obtained from animal models to biomarkers that are useful in evaluating data from epilepsy patients. [ABSTRACT FROM AUTHOR]

Background: Treatment of apnea is highly dependent on the type of apnea. Chest impedance (CI) has inaccuracies in monitoring respiration, which compromises accurate apnea classification. Electrical activity of the diaphragm measured by transcutaneous electromyography (EMG) is feasible in preterm infants and might improve the accuracy of apnea classification. Objectives: To compare the accuracy of apnea classification based on diaphragmatic EMG (dEMG) and CI tracings in preterm infants. Methods: Fifteen cases of central apnea, 5 of obstructive apnea, and 10 of mixed apnea were selected from recordings containing synchronized continuous tracings of respiratory inductive plethysmography (RIP), airway flow, heart rate (HR), oxygen saturation (SpO2), and breathing activity measured by dEMG and CI. Twenty-two assessors (neonatologists, pediatricians-in-training, and nurses) classified each apnea twice; once based on dEMG, HR, and SpO2 tracings, and once based on CI, HR, and SpO2. The assessors were blinded to the type of respiratory tracing (dEMG or CI) and to the RIP and flow tracings. Results: In total 1,320 assessments were performed, and in 71.1% the apnea was classified correctly. Subgroup analysis based on respiratory tracing showed that 74.8% of the dEMG tracings were classified correctly compared to 67.3% of the CI tracings (p < 0.001). This improved apnea classification based on dEMG was present for central (86.7 vs. 80.3%, p < 0.02) and obstructive (56.4 vs. 32.7%, p < 0.001) apnea. The improved apnea classification based on dEMG tracing was independent of the type of assessor. Conclusion: Transcutaneous dEMG improves the accuracy of apnea classification when compared to CI in preterm infants, making this technique a promising candidate for future monitoring systems. [ABSTRACT FROM AUTHOR]

Sleep apnea is a independent pathology and a powerful stress for the organism. Apnea is a cause of stress and strengthens the body under stress. We studied 30 men aged 34 to 57 years: 22 patients with obstructive sleep apnea and 8 patients with central sleep apnea. We explored a drop of blood in HUMACOUNT, mod. HUMACOUNT (Firm Human GmbH, Germany), bought of grant budget RF/420/7-270/12. We investigated parameters of platelet: PLT, MPV, PDWс and PCT. The analysis of the data was performed using statistical programs “Origin 4.1’’ (Microsoft. Software, Inc) and Microsoft Excel, evaluated Student and criteria Pearson. Protocol of research was adequate Helsinki Declaration. Our results in patients with obstructive apnea: PLT=109x109±40x109l; MPV =7,7±3,0fl; PCT=0,08x10-2±0,02x10-2%; PDWС =33,4±3,6%; in patients with central apnea - PLT=142x109±50x109l; MPV=6,4±2,0fl; PCT=0,09x10-2±0,03x10-2%; PDWС=32,7±3,0; in control - PLT=250x109±40x109l; MPV=11,0±4,0fl; PCT=0,25x10-2±0,05x10-2%; PDWС=36,2±4,0%. Interrupted we analyzed the number of platelets and platelet indices for determining homeostasis in stress disease. Stress body reduces the number of platelets. But if apnea is a disease of the fourth rank stress, platelet factors fluctuate within normal limits. Our data have practical significance for biomedicine. We propose a new marker for apnea: platelet composes.

Background and objectives: Obstructive sleep apnea syndrome (OSAS) and heart failure (HF) are increasing in prevalence with a greater impact on the health system. The aim of this study was to assess the particularities of patients with OSAS and HF, focusing on the new class of HF with mid-range ejection fraction (HFmrEF, EF = 40%−49%), and comparing it with reduced EF (HFrEF, EF < 40%) and preserved EF (HFpEF, EF ≥ 50%). Materials and Methods: A total of 143 patients with OSAS and HF were evaluated in three sleep labs of “Victor Babes” Hospital and Cardiovascular Institute, Timisoara, Western Romania. We collected socio-demographic data, anthropometric sleep-related measurements, symptoms through sleep questionnaires and comorbidity-related data. We performed blood tests, cardio-respiratory polygraphy and echocardiographic measurements. Patients were divided into three groups depending on ejection fraction. Results: Patients with HFmrEF were older (p = 0.0358), with higher values of the highest systolic blood pressure (mmHg) (p = 0.0016), higher serum creatinine (p = 0.0013), a lower glomerular filtration rate (p = 0.0003), higher glycemic levels (p = 0.008) and a larger left atrial diameter (p = 0.0002). Regarding comorbidities, data were presented as percentage, HFrEF vs. HFmrEF vs. HFpEF. Higher prevalence of diabetes mellitus (52.9 vs. 72.7 vs. 40.2, p = 0.006), chronic kidney disease (17.6 vs. 57.6 vs. 21.5, p < 0.001), tricuspid insufficiency (76.5 vs. 84.8 vs.59.1, p = 0.018) and aortic insufficiency (35.3 vs.42.4 vs. 20.4, p = 0.038) were observed in patients with HFmrEF, whereas chronic obstructive pulmonary disease(COPD) (52.9 vs. 24.2 vs.18.3, p = 0.009), coronary artery disease(CAD) (82.4 vs. 6.7 vs. 49.5, p = 0.026), myocardial infarction (35.3 vs. 24.2 vs. 5.4, p < 0.001) and impaired parietal heart kinetics (70.6 vs. 68.8 vs. 15.2, p < 0.001) were more prevalent in patients with HFrEF. Conclusions: Patients with OSAS and HF with mid-range EF may represent a new group with increased risk of developing life-long chronic kidney disease, diabetes mellitus, tricuspid and aortic insufficiency. COPD, myocardial infarction, impaired parietal kinetics and CAD are most prevalent comorbidities in HFrEF patients but they are closer in prevalence to HFmrEF than HFpEF.

Sleep apnea, which is the periodic cessation of breathing during sleep, is a major health problem affecting over 10 million people in the United States and is associated with several sequelae, including hypertension and stroke. Clinical studies suggest that abnormal carotid body (CB) activity may be a driver of sleep apnea. Because gaseous molecules are important determinants of CB activity, aberrations in their signaling could lead to sleep apnea. Here, we report that mice deficient in heme oxygenase-2 (HO-2), which generates the gaseous molecule carbon monoxide (CO), exhibit sleep apnea characterized by high apnea and hypopnea indices during rapid eye movement (REM) sleep. Similar high apnea and hypopnea indices were also noted in prehypertensive spontaneously hypertensive (SH) rats, which are known to exhibit CB hyperactivity. We identified the gaseous molecule hydrogen sulfide (H2S) as the major effector molecule driving apneas. Genetic ablation of the H2S-synthesizing enzyme cystathionine-γ-lyase (CSE) normalized breathing in HO-2-/- mice. Pharmacologic inhibition of CSE with L-propargyl glycine prevented apneas in both HO-2-/- mice and SH rats. These observations demonstrate that dysregulated CO and H2S signaling in the CB leads to apneas and suggest that CSE inhibition may be a useful therapeutic intervention for preventing CB-driven sleep apnea. [ABSTRACT FROM AUTHOR]

Obstructive apnea (OA) can exert significant effects on renal sympathetic nerve activity (RSNA) and hemodynamic parameters. The present study focuses on the modulatory actions of RSNA on OA-induced sodium and water retention. The experiments were performed in renal-denervated rats (D; N = 9), which were compared to sham (S; N = 9) rats. Mean arterial pressure (MAP) and heart rate (HR) were assessed via an intrafemoral catheter. A catheter was inserted into the bladder for urinary measurements. OA episodes were induced via occlusion of the catheter inserted into the trachea. After an equilibration period, OA was induced for 20 s every 2 min and the changes in urine, MAP, HR and RSNA were recorded. Renal denervation did not alter resting MAP (S: 113 ± 4 vs D: 115 ± 4 mmHg) or HR (S: 340 ± 12 vs D: 368 ± 11 bpm). An OA episode resulted in decreased HR and MAP in both groups, but D rats showed exacerbated hypotension and attenuated bradycardia (S: -12 ± 1 mmHg and -16 ± 2 bpm vs D: -16 ± 1 mmHg and 9 ± 2 bpm; P < 0.01). The basal urinary parameters did not change during or after OA in S rats. However, D rats showed significant increases both during and after OA. Renal sympathetic nerve activity in S rats increased (34 ± 9%) during apnea episodes. These results indicate that renal denervation induces elevations of sodium content and urine volume and alters bradycardia and hypotension patterns during total OA in unconscious rats.

Evidence of impaired function of orexin neurons has been found in individuals with cardiorespiratory disorders, such as obstructive sleep apnea (OSA) and sudden infant death syndrome (SIDS), but the mechanisms responsible are unknown. Individuals with OSA and SIDS experience repetitive breathing cessations and/or rebreathing of expired air, resulting in hypoxia/hypercapnia (H/H). In this study, we examined the responses of fluorescently identified rat orexin neurons in the lateral hypothalamus to acute H/H to test if and how these neurons alter their activity and function during this challenge. Experiments were conducted in an in vitro slice preparation using voltage-clamp and current-clamp configurations. H/H (10 min) induced hyperpolarization, accompanied by rapid depression, and finally, cessation of firing activity in orexin neurons. Hypoxia alone had similar but less potent effects. H/H did not alter the frequency of inhibitory glycinergic postsynaptic currents. The frequency of GABAergic currents was diminished but only at 8-10 min of H/H. In contrast, the frequency of excitatory glutamatergic postsynaptic events was diminished as early as 2-4 min of H/H. In the presence of glutamatergic receptor blockers, the inhibitory effects of H/H on the firing activity and membrane potential of orexin neurons persisted but to a lesser extent. In conclusion, both direct alteration of postsynaptic membrane properties and diminished glutamatergic neurotransmission likely contribute to the inhibition of orexin neurons by H/H. These mechanisms could be responsible for the decreased function of orexin in individuals at risk for OSA and SIDS. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study was conducted to investigate the sleep symptoms and polysomnographic patterns of obstructive sleep apnea in overweight and obese children. MATERIALS & METHODS: Overweight or obese children aging 6-18 yr old referred during 2010 to Endocrinology Clinic of Ghods Hospital in Ghazvin, central Iran were enrolled in the study. Polysomnography was done for the diagnosis of obstructive sleep apnea and the BEARS and Children's Sleep Habits questionnaires were used to survey sleep behaviors. RESULTS: We enrolled 30 children (14 males, 16 females). Twenty-one cases had body mass index (BMI) >95% and 9 had 85% CONCLUSION: Prevalence of obstructive sleep apnea is high among overweight and obese children. Physicians should be familiar with its manifestations and consider polysomnography as an invaluable diagnostic test. There was no relation between the degree of obesity and severity of obstructive sleep apnea. [ABSTRACT FROM AUTHOR]