Sleep disordered breathing in medically stable patients with myasthenia gravis

We investigate sleep and breathing in clinically stable myasthenia gravis (MG) patients and ask weather sleep disordered breathing (SDB) is causally linked with MG. Nineteen MG patients with a mean disease duration of 9.7 years underwent sleep studies in two consecutive nights. The primary outcome measure was the respiratory disturbance index (RDI) in terms of snoring and apneas/hypopneas. Further outcome measurements were total sleep time, sleep stage distribution and the number of arousals. A clinically relevant SDB in terms of obstructive sleep apnea (OSA) (defined as RDI > 10/h) was found in four patients. There were only a few central apneas (central apnea index: 0.19 ± 0.4/h). We did not find a relationship between maximum inspiratory pressure and SDB ( r  = −0.03). There is no evidence for a causal relationship between medically stable MG and SDB in terms of OSA. The extent of respiratory muscle weakness failed to correlate with SDB. Furthermore, our study does not confirm the high occurrence of central respiratory events during sleep in patients with well-controlled MG.     

Combined adaptive servo-ventilation and automatic positive airway pressure (anticyclic modulated ventilation) in co-existing obstructive and central sleep apnea syndrome and periodic breathing

BackgroundThe co-existence of obstructive and central sleep apnea/hypopnea syndrome (OSAS) and periodic breathing is common in patients with and without underlying heart diseases. While automatic continuous positive airway pressure (APAP) has proven to effectively treat OSAS, the adaptive servo-ventilation (ASV) sufficiently improves periodic breathing. This is the first trial on a device which combines both treatment modes.MethodsPilot study on a two-week treatment in patients with co-existing obstructive and central and periodic breathing disturbances during sleep. Twelve consecutive patients (9 male, 3 female, age 56.9 ± 10.6 years, BMI 32.4 ± 5.5 kg/m²) were treated with a new algorithm which combines APAP and ASV (also called anticyclic modulated ventilation (ACMV), SOMNOventCR^®, Weinmann, Hamburg, Germany). Seven suffered from arterial hypertension, coronary heart disease and mitral regurgitation, none from congestive heart failure.ResultsThe total apnea–hypopnea index (AHI) improved from 43.8 ± 24.0/h to 2.1 ± 2.4 (p < 0.01), the obstructive AHI from 12.8 ± 14.3/h to 0.3 ± 0.6/h (p < 0.01) and the central AHI from 31.0 ± 17.5/h to 1.7 ± 2.0/h (p < 0.01). Moreover, there was a significant improvement in the total number of arousals, respiratory induced arousals, oxygen saturation and sleep profile.ConclusionThe algorithm combining automatic continuous positive airway pressure (CPAP) and ASV normalizes all types of co-existing obstructive and central apnea/hypopnea and periodic breathing.     

Differences in arousal response between aged and middle-aged patients with obstructive sleep apnea syndrome

Abstract The aim of this study is to show the clinical significance of the differences in arousal response at a termination of apnea/hypopnea between aged and middle-aged patients with obstructive sleep apnea syndrome (OSAS). We polygraphically assessed electrocardiographic (ECG) and electroencephalographic (EEG) arousal. Electrocardiographic arousal was defined as an abrupt increase in heart rate at a termination of apnea/hypopnea. Our findings showed that EEG and ECG arousal at a termination of apnea/hypopnea were significantly suppressed in aged patients with OSAS, which might provide useful information on the pathophysiology of OSAS.     

The influence of sleep position and obesity on sleep apnea

The influence of sleep position and the degree of obesity were examined in 257 subjects with sleep apnea. Subjects were divided into three groups according to obesity: normal weight (body mass index (BMI) under 24.0 kg/m2), mild obese (BMI 24.0-26.4 kg/m2) and obese group (BMI 26.4 kg/m2 and heavier). The apnea + hypopnea index (AHI), the intraesophageal pressure and the lowest oxygen saturation became significantly worse according to the degree of obesity. The subjects were also divided into two groups according to the reduction in the AHI by lateral position: good responders showed 50% or more reduction of AHI in lateral position and poor responders indicated less than 50% reduction. The percentage of good responders to sleep position change was 90.9% in normal weight group, 74.0% in mild obese group and 57.4% in the obese group. The ratio of the subjects who had indicated two or more obstructive sites in normal weight group was 36.0% in good responders and 40.0% in poor responders. The ratio in the mild obese group was 51.8% in good responders and 66.7% in poor responders. In the obese group, the ratio was 59.4% in good responders and 78.9% in poor responders.     

Uvulopalatopharyngoplasty for obstructive sleep-related breathing disorders: one-year follow up

The effectiveness of uvulopalatopharyngoplasty was evaluated in 28 patients (25 men and three women; mean age 47.6 years) with obstructive sleep apnea by comparing preoperative daytime polysomnography with those carried out 6 months and 1 year postoperatively. The mean apnea plus hypopnea index (AHI) in the supine position decreased from 51.0/h to 23.0/h 6 months postoperatively and 57.1% of patients showed a 50% or more reduction of AHI. By changing the sleep position from supine to lateral, 71.4% of the 28 patients indicated a 50% or more reduction in AHI before surgery, which increased to 92.3% of 26 patients 6 months postoperatively. The positive results of uvulopalatopharyngoplasty were maintained at least until 1 year after surgery.     

Obstructive sleep apnea in a clinical series of adult epilepsy patients: frequency and features of the comorbidity

PURPOSE: The aim of this study was to evaluate the rate and features of obstructive sleep apnea (OSA) in adult epilepsy patients. METHODS: Two hundred eighty-three adult epilepsy patients (137 men; mean age, 33 years; range, 18-70 years) were prospectively screened for OSA by means of a structured interview. Those in whom OSA was clinically suspected were monitored for a full night by using a portable device (Polymesam), and OSA was diagnosed when they had an Apnea/Hypopnea Index greater than five. RESULTS: Coexistence of OSA with epilepsy was found in 10.2% (15.4% of the male and 5.4% of the female) epilepsy patients investigated. The OSA was mild in 66.6%, moderate in 22.2%, and severe in 11.1% of the cases. The "epilepsy + OSA" patients were older, heavier, more frequently male, and sleepier (p < 0.05) than those with "epilepsy only." Furthermore, they experienced their first seizure at an older age (p < 0.05). CONCLUSIONS: Systematic investigation reveals that OSA is frequent in epilepsy patients. The major risk factors for OSA in our epilepsy patients were the same as those typically found in the general population. Of the epilepsy-related factors, older age at onset of seizures appears to be significantly related to comorbidity with OSA (p < 0.05). The presence in epilepsy patients of these features should alert the clinician to the possibility of an underlying OSA.     

Predominant obstructive or central sleep apnea in patients with atrial fibrillation: influence of characterizing apneas versus apneas and hypopneas

Objective/backgroundSleep-disordered breathing (SDB) is common in patients with atrial fibrillation (Afib). Although a high proportion of respiratory events are hypopneas, previous studies have only used apneas to differentiate obstructive (OSA) from central (CSA) sleep apnea. This study investigated the impact of using apneas and hypopneas versus apneas only to define the predominant type of SDB in Afib patients with preserved ejection fraction.Patients/methodsThis retrospective analysis was based on high-quality cardiorespiratory polygraphy (PG) recordings (07/2007–03/2016) that were re-analyzed using 2012 American Academy of Sleep Medicine criteria, with differentiation of apneas and hypopneas as obstructive or central. Classification of predominant (>50% of events) OSA and CSA was defined based on apneas only (OSA_AI and CSA_AI) or apneas and hypopneas (OSA_AHI and CSA_AHI). SDB was defined as an apnea–hypopnea index ≥5/h.ResultsA total of 211 patients were included (146 male, age 68.7 ± 8.5 y). Hypopneas accounted for >50% of all respiratory events. Based on apneas only, 46% of patients had predominant OSA and 44% had predominant CSA. Based on apneas and hypopneas, the proportion of patients with OSA was higher (56%) and that with CSA was lower (36%). In the subgroup of patients with moderate to severe SDB (AHI ≥ 15/h), the proportion with predominant CSA was 55.2% based on apneas only versus 42.1% with apneas and hypopneas.ConclusionsIn hospitalized patients with Afib and SDB, use of apneas and hypopneas versus apneas alone had an important influence on the proportion of patients classified as having predominant OSA or CSA.     

Polysomnographic features of idiopathic central sleep apnea

Two patients with idiopathic central sleep apnea (ICSA), which is an uncommon condition, were recently encountered. This study examines the polysomnographic features of ICSA. The characteristic findings of ICSA are summarized as follows: (i) central apneas and hypopneas are progressively less frequent as sleep state deepens from stage 1 to stage 2 to stage 3 + 4 to stage REM (rapid eye movement); (ii) desaturation related to apneas and hypopneas is mild; and (iii) periodic breathing is commonly observed. However, the two patients demonstrated apparently different findings. It is suggested that the mechanisms underlying apnea and hypopnea in ICSA are heterogeneous.     

SIESTA - Home sleep study with BresoDx for obstructive sleep apnea: a randomized controlled trial

Study objectivesThe objectives of this study were to evaluate (1) the accuracy of the clinical diagnosis of obstructive sleep apnea (OSA) informed by the home sleep study with a Type 4 portable monitor BresoDx® versus Type 1 polysomnography (PSG); and (2) agreement of the apnea-hypopnea index (AHI) compared between BresoDx and PSG.Material and methodsThis was a randomized, parallel, multicentre, single-blind, pragmatic controlled trial enrolling adults referred to three Ontario sleep clinics for suspected OSA. Participants were randomized to BresoDx followed by PSG (one-night apart) or PSG followed by BresoDx sleep testing sequence arms. The primary outcomes included the accuracy of clinical diagnosis and OSA severity measured by AHI between tests.ResultsIn sum, 233 participants completed both sleep studies and 206 completed physician consultation visits. The agreement between clinical diagnosis informed by PSG versus BresoDx was fair (Cohen's kappa coefficient = 0.28). The sensitivity of BresoDx-informed clinical diagnosis against PSG was between 0.86 and 0.89, and the specificity between 0.38 and 0.44. For AHI cut-off of ≥5 events/hour the sensitivity, specificity and positive and negative predictive values were 0.85, 0.48, 0.81 and 0.54.ConclusionsHome sleep apnea testing with BresoDx can be used in a referral population with a high pretest probability of OSA similar to other Type IV devices. This study complements the existing body of evidence suggesting that home testing with portable devices plays a valuable role for diagnosing of OSA in a variety of settings.SIESTA trial registrationwww.clinicaltrials.gov (Identifier: NCT02003729).     

Differential diagnosis of obstructive sleep apnea syndrome patients and snorers using cephalograms

Severe snoring is thought by many to be an early stage of obstructive sleep apnea syndrome (OSAS), but the anatomical relation between snoring and OSAS, if any, has remained unclear. To compare the morphology of the airway between snorers and OSAS patients for possible similarities, we conducted a cephalometric analysis of Japanese OSAS patients (n=10), habitual snorers (n=10), and non-snoring controls (n=50). There was no significant difference in SNB (the angle formed by the sella, nasion and point B) between OSAS patients and the control subjects. Obstructive sleep apnea syndrome patients tended to have an anteriorly positioned maxilla, and an anteroposterior misalignment between the maxilla and mandible. There was also a tendency toward skeletal openbite. Both OSAS patients and snorers had large tongues and large soft palates, thus causing constriction of the airway with resultant smaller airway diameter and smaller airway surface area. Significant differences between OSAS patients and snorers were found in thickness and length of soft palate surface area, and thickness, length, and position of the hyoid bone. These results suggest that cephalographic measurements may be of considerable use in determining the seriousness of a patient's condition.     

Intensity of snoring in patients with sleep-related breathing disorders

The intensity of snoring was measured in 73 patients with snoring or sleep apnea using a noise meter. The mean intensity of snoring at 50 cm in front of the mouth was 61.7 dB in the supine position and 53.7 dB in the lateral position. There existed a definite correlation between the logarithmic transformation of the intra-esophageal pressure amplitude and the intensity of snoring in the supine and lateral decubitus positions. These findings suggest that the intensity of snoring may be a useful index for sleep-related breathing disorders.     

脑血管病与阻塞性睡眠呼吸暂停综合征的关系

目的研究脑血管病与阻塞性睡眠呼吸暂停综合征（ＯＳＡＳ）的关系。方法对比分析年龄、性别和体重指数均匹配的脑血管病（ＣＶＤ）患者和正常对照各３０例的多导睡眠图。结果发现ＣＶＤ组ＯＳＡＳ发病率高达７０％（对照组２０％，Ｐ＜０．０１），其收缩期血压，低氧时间、平均和最低血氧饱和度以及中枢性呼吸暂停次数均与对照组差别显著。结论认为ＯＳＡＳ是ＣＶＤ被忽视的危险因素，但不排除ＣＶＤ诱发了ＯＳＡＳ的可能，两者形成恶性循环，影响ＣＶＤ康复     

Sleep Perception in Obstructive Sleep Apnea: A Study Using Polysomnography and the Multiple Sleep Latency Test

MethodsWe recruited patients who visited our sleep clinic for the evaluation of their snoring and/or observed OSA. Participants completed a structured questionnaire and underwent overnight polysomnography. On the following day, five sessions of the multiple sleep latency test (MSLT) were applied. We divided the patients into two groups: normal sleep perception and abnormal perception. The abnormal-perception group included patients whose perceived total sleep time was less than 80% of that measured in polysomnography.ResultsFifty OSA patients were enrolled from a university hospital sleep clinic. Excessive daytime sleepiness, periodic limb movement index (PLMI), and the presence of dreaming were positively associated with poor sleep perception. REM sleep near the sleep termination exerted important effects. Respiratory disturbance parameters were not related to sleep perception. There was a prolongation in the sleep latency in the first session of the MSLT and we suspected that a delayed sleep phase occurred in poor-sleep perceivers.ConclusionsAs an objectively good sleep does not match the subjective good-sleep perception in OSA, physicians should keep in mind that OSA patients who perceive that they have slept well does not mean that their OSA is less severe.     

Total durations of respiratory events are modulated within REM and NREM sleep by sleeping position and obesity in OSA patients

BackgroundSupine sleeping position and obesity are well-known risk factors for obstructive sleep apnea (OSA) and modulate the risk for OSA-related daytime symptoms. Although respiratory event durations are associated with OSA-related severe health consequences, it is unclear how sleeping position, obesity, and daytime sleepiness are associated with respiratory event durations during REM and NREM sleep. We hypothesize that irrespective of the apnea-hypopnea index (AHI), respiratory event durations differ significantly between various OSA subgroups during REM and NREM sleep.MethodsOne night in-lab polysomnographic recordings were retrospectively analyzed from 1910 untreated suspected OSA patients. 599 patients (AHI ≥ 5) were included in study and divided into subgroups based on positional dependency, BMI, and daytime sleepiness (Epworth Sleepiness Scale and Multiple Sleep Latency Test). Differences in total hypopnea time (THT), total apnea time (TAT), and total apnea-hypopnea time (TAHT) within REM and NREM sleep between the subgroups were evaluated.ResultsDuring REM sleep, positional OSA patients had lower THT (OR = 0.952, p < 0.001) and TAHT (OR = 0.943, p < 0.001) than their non-positional counterparts. Compared to normal-weight patients (BMI < 25 kg/m²), obese patients (BMI ≥ 30 kg/m²) had lower THT, TAT, and TAHT (ORs = 0.942–0.971, p ≤ 0.009) during NREM sleep but higher THT (OR = 1.057, p = 0.001) and TAHT (OR = 1.052, p = 0.001) during REM sleep. No significant differences were observed in THT, TAT, and TAHT between patients with and without daytime sleepiness.ConclusionRegardless of the AHI, respiratory event durations vary significantly between OSA sub-groups during REM and NREM sleep. Therefore, to personalize OSA severity estimation the diagnosis should be tailored based on patient's demographics, clinical phenotype, and PSG characteristics.     

Obstructive sleep apnea in epilepsy patients: the Sleep Apnea scale of the Sleep Disorders Questionnaire (SA-SDQ) is a useful screening instrument for obstructive sleep apnea in a disease-specific population

OBJECTIVE: To determine useful cutoffs on the Sleep Apnea scale of the Sleep Disorders Questionnaire (SA-SDQ) in an epilepsy population. BACKGROUND: Epilepsy and obstructive sleep apnea (OSA) frequently coexist, and treating OSA in epilepsy patients may reduce seizure frequency and improve daytime sleepiness. The SA-SDQ, a 12-item validated measure of sleep-related breathing disorders, may be a useful tool to screen epilepsy patients for OSA, although appropriate cutoff points have not been established in this population. Previously suggested SA-SDQ cutoff points for OSA in a non-epilepsy population were 32 for women and 36 for men. PATIENTS AND METHODS: One hundred twenty-five subjects with epilepsy undergoing polysomnography completed a survey about their sleep, including the 12-item SA-SDQ scale. Receiver-operating characteristics curves were constructed to determine optimal sensitivity and specificity. RESULTS: Sixty-nine of the 125 subjects (45%) had apnea-hypopnea indices greater than five, indicating OSA. The area under the curve was 0.744 for men and 0.788 for women. For men, an SA-SDQ score of 29 provided a sensitivity of 75% and a specificity of 65%. For women, an SA-SDQ score of 26 provided a sensitivity of 80% and a specificity of 67%. CONCLUSIONS: The SA-SDQ is a useful screening instrument for OSA in an epilepsy population. Our results indicate that the previously suggested cutoffs for OSA (36 for men and 32 for women) may be too high for this specific population. We suggest screening cutoffs of 29 for men and 26 for women.