Sleep disordered breathing and mortality: eighteen-year follow-up of the Wisconsin sleep cohort

BACKGROUND: Sleep-disordered breathing (SDB) is a treatable but markedly under-diagnosed condition of frequent breathing pauses during sleep. SDB is linked to incident cardiovascular disease, stroke, and other morbidity. However, the risk of mortality with untreated SDB, determined by polysomnography screening, in the general population has not been established. METHODS: An 18-year mortality follow-up was conducted on the population-based Wisconsin Sleep Cohort sample (n = 1522), assessed at baseline for SDB with polysomnography, the clinical diagnostic standard. SDB was described by the number of apnea and hypopnea episodes/hour of sleep; cutpoints at 5, 15 and 30 identified mild, moderate, and severe SDB, respectively. Cox proportional hazards regression was used to estimate all-cause and cardiovascular mortality risks, adjusted for potential confounding factors, associated with SDB severity levels. RESULTS: All-cause mortality risk, adjusted for age, sex, BMI, and other factors was significantly increased with SDB severity. The adjusted hazard ratio (HR, 95% CI) for all-cause mortality with severe versus no SDB was 3.0 (1.4,6.3). After excluding persons who had used CPAP treatment (n = 126), the adjusted HR (95% CI) for all-cause mortality with severe versus no SDB was 3.8 (1.6,9.0); the adjusted HR (95% CI) for cardiovascular mortality was 5.2 (1.4,19.2). Results were unchanged after accounting for daytime sleepiness. CONCLUSIONS: Our findings of a significant, high mortality risk with untreated SDB, independent of age, sex, and BMI underscore the need for heightened clinical recognition and treatment of SDB, indicated by frequent episodes of apnea and hypopnea, irrespective of symptoms of sleepiness.     

Sleep architecture based on sleep depth and propensity: patterns in different demographics and sleep disorders and association with health outcomes

Study ObjectivesConventional metrics of sleep quantity/depth have serious shortcomings. Odds-Ratio-Product (ORP) is a continuous metric of sleep depth ranging from 0 (very deep sleep) to 2.5 (full-wakefulness). We describe an ORP-based approach that provides information on sleep disorders not apparent from traditional metrics.MethodsWe analyzed records from the Sleep-Heart-Health-Study and a study of performance deficit following sleep deprivation. ORP of all 30-second epochs in each PSG and percent of epochs in each decile of ORPs range were calculated. Percentage of epochs in deep sleep (ORP < 0.50) and in full-wakefulness (ORP > 2.25) were each assigned a rank, 1–3, representing first and second digits, respectively, of nine distinct types (“1,1”, “1,2” … ”3,3”). Prevalence of each type in clinical groups and their associations with demographics, sleepiness (Epworth-Sleepiness-Scale, ESS) and quality of life (QOL; Short-Form-Health-Survey-36) were determined.ResultsThree types (“1,1”, “1,2”, “1,3”) were prevalent in OSA and were associated with reduced QOL. Two (“1,3” and “2,3”) were prevalent in insomnia with short-sleep-duration (insomnia-SSD), but only “1,3” was associated with poor sleep depth and reduced QOL, suggesting two phenotypes in insomnia-SSD. ESS was high in types “1,1” and “1,2”, and low in “1,3” and “2,3”. Prevalence of some types increased with age while in others it decreased. Other types were either rare (“1,1” and “3,3”) or high (“2,2”) at all ages.ConclusionsThe proposed ORP histogram offers specific and unique information on the underlying neurophysiological characteristics of sleep disorders not captured by routine metrics, with potential of advancing diagnosis and management of these disorders.     

Unbiased categorical classification of pediatric sleep disordered breathing

Study Objectives:

To classify pediatric sleep disordered breathing (SDB) using unbiased approaches. In children, decisions regarding severity and treatment of SDB are conducted solely based on empirical observations. Although recognizable entities clearly exist under the SDB spectrum, neither the number of SDB categories nor their specific criteria have been critically defined.

Design:

retrospective cohort analysis and random prospective cohort

Setting:

community and clinical sample

Patients or Participants:

Urban 5- to 9-year-old community children undergoing overnight sleep study (NPSG), and a comparable prospectively recruited clinical SDB sample.

Interventions:

n/a

Measurements and Results:

Principal component analysis was used to identify the uniqueness of the polysomnographically derived measures that are routinely used in clinical settings: apnea-hypopnea index, apnea index, obstructive apnea index, nadir SpO₂, spontaneous arousal index and respiratory arousal index. These measures were then incorporated using unbiased data mining approaches to further characterize and discriminate across categorical phenotypes. Of 1,133 subjects, 52.8% were habitual snorers. Six categorical phenotypes clustered without any a priori hypothesis. Secondly, a non-hierarchical model that incorporated 6 NPSG-derived measures enabled unbiased identification of algorithms that predicted these 6 severity-based clusters. Thirdly, a hierarchical model was developed and performed well on all severity-based clusters. Classification and predictive models were subsequently cross-validated statistically as well as clinically, using 2 additional datasets that included 259 subjects. Modeling reached ∼93% accuracy in cluster assignment.

Conclusions:

Data-driven analysis of conventional NPSG-derived indices identified 6 distinct clusters ranging from a cluster with normal indices toward clusters with more abnormal indices. Categorical assignment of individual cases to any of such clusters can be accurately predicted using a simple algorithm. These clusters may further enable prospective unbiased characterization of clinical outcomes and of genotype-phenotype interactions across multiple datasets.

Citation:

Spruyt K; Verleye G; Gozal D. Unbiased categorical classification of pediatric sleep disordered breathing. SLEEP 2010;33(10):1341-1347.     

Association between polysomnographic sleep measures and health-related quality of life in obstructive sleep apnea

Many facets of health-related quality of life are diminished in obstructive sleep apnea (OSA) as they are in other chronic medical conditions. We speculated that impairment in health-related quality of life (HRQoL) might result from the fatigue and daytime somnolence associated with the sleep disorder, as an indirect result from the fragmentation of night-time sleep in OSA. Our hypothesis was that sleep fragmentation measures would correlate with poorer HRQoL measured by medical outcomes study (MOS) subscales. Thirty-nine patients with polysomnographically-confirmed OSA participated in this study. Pearson's correlations were performed with the following sleep architecture variables: wake after sleep onset, the total number of brief arousals, the number of respiratory-related arousals, the rate of respiratory events per hour, and total sleep time. To our surprise, although the total number of arousals was associated with health distress (r=-0.481, P < 0.005), it did not correlate with any other subscales indicating poorer physical and mental health. The relatively insensitive measure of total sleep time (TST) correlated in the expected direction with most subscales. However, after controlling for age and gender, respiratory disturbance indices (RDI) and/or number of arousals emerged as significantly associated with mobility, cognitive functioning, social functioning, energy and fatigue, and health distress. Our findings suggest that polysomnographic indicators of sleep quality and sleep continuity may be an important influence determining many aspects of HRQoL in OSA patients.     

Effect of Continuous Positive Airway Pressure on Sleep Structure in Heart Failure Patients with Central Sleep Apnea

Study Objectives:

At termination of obstructive apneas, arousal is a protective mechanism that facilitates restoration of upper airway patency and airflow. Treating obstructive sleep apnea (OSA) by continuous positive airway pressure (CPAP) reduces arousal frequency indicating that such arousals are caused by OSA. In heart failure (HF) patients with central sleep apnea (CSA), however, arousals frequently occur several breaths after apnea termination, and there is uncertainty as to whether arousals from sleep are a consequence of CSA. If so, they should diminish in frequency when CSA is attenuated. We therefore sought to determine whether attenuation of CSA by CPAP reduces arousal frequency.

Design:

Randomized controlled clinical trial.

Patients and Setting:

We examined data from 205 HF patients with CSA (apnea-hypopnea index [AHI] ≥ 15, > 50% were central) randomized to CPAP or control who had polysomnograms performed at baseline and 3 months later.

Measurements and Results:

In the control group, there was no change in AHI or frequency of arousals. In the CPAP-treated group, the AHI decreased significantly (from [mean ± SD] 38.9 ± 15.0 to 17.6 ± 16.3, P < 0.001) but neither the frequency of arousals nor sleep structure changed significantly.

Conclusion:

These data suggest that attenuation of CSA by CPAP does not reduce arousal frequency in HF patients. We conclude that arousals were not mainly a consequence of CSA, and may not have been acting as a defense mechanism to terminate apneas in the same way they do in OSA.

Citation:

Ruttanaumpawan P; Logan AG; Floras JS; Bradley TD. Effect of Continuous Positive Airway Pressure on Sleep Structure in Heart Failure Patients with Central Sleep Apnea. SLEEP 2009;32(1):91-98.     

Longitudinal Evaluation of Sleep-Disordered Breathing and Sleep Symptoms with Change in Quality of Life: The Sleep Heart Health Study (SHHS)

Study Objectives:

Findings from population studies evaluating the progression and incidence of sleep disordered breathing have shown evidence of a longitudinal increase in the severity of sleep disordered breathing. The present study evaluates the association among changes in sleep disordered breathing, sleep symptoms, and quality of life over time.

Design:

Prospective cohort study. Data were from the Sleep Heart Health Study.

Setting:

Multicenter study.

Participants:

Three thousand seventy-eight subjects aged 40 years and older from the baseline and follow-up examination cycles were included.

Measurements:

The primary outcomes were changes in the Physical Component Summary and Mental Component Summary scales obtained from the Medical Outcomes Study Short-Form Health Survey. The primary exposure was change in the respiratory disturbance index obtained from unattended overnight polysomnograms performed approximately 5 years apart. Other covariates included measures of excessive daytime sleepiness and difficulty initiating and maintaining sleep.

Results:

Mean respiratory disturbance index increased from 8.1 ± 11 SD at baseline to 10.9 ± 14 (P < 0.0001) at follow-up. The mean Physical Component Summary and Mental Component Summary scores were 48.5 and 54.1 at baseline and 46.3 and 54.8 at follow-up. No associations between change in respiratory disturbance index and changes in Physical Component Summary or Mental Component Summary scores were seen. However, worsening of difficulty initiating and maintaining sleep and excessive daytime sleepiness were significantly associated with lower quality of life.

Conclusions:

A slight increase in severity of sleep disordered breathing was seen over 5 years; this was not associated with worsening of quality of life. However, subjective symptoms of quality of sleep and daytime sleepiness were associated with declining quality of life.

Citation:

Silva GE; An MW; Goodwin JL; Shahar E; Redline S; Resnick H; Baldwin CM; Quan SF. Longitudinal evaluation of sleep-disordered breathing and sleep symptoms with change in quality of life: the Sleep Heart Health Study (SHHS). SLEEP 2009;32(8):1049-1057.     

The Utility of Three Screening Questionnaires for Obstructive Sleep Apnea in a Sleep Clinic Setting

Purpose

The aim of this study was to determine the diagnostic value of three screening questionnaires in identifying Korean patients at high risk for obstructive sleep apnea (OSA) in a sleep clinic setting in Korea.

Materials and Methods

Data were collected from 592 adult patients with suspected OSA who visited a sleep center. All patients completed the Sleep Apnea of Sleep Disorder Questionnaire (SA-SDQ), the Berlin questionnaire, and the STOP-Bang questionnaire. Estimated OSA risk was compared to a diagnosis of OSA. The sensitivity, specificity, positive predictive value, and negative predictive value were calculated for each questionnaire.

Results

The prevalence of OSA was 83.6% using an apnea-hypopnea index (AHI) ≥5/h and 58.4% for an AHI ≥15/h. The STOP-Bang questionnaire had a high sensitivity (97% for AHI ≥5/h, 98% for AHI ≥15/h), but the specificity was low (19% and 11%, respectively). In contrast, the sensitivity of the SA-SDQ was not high enough (68% for AHI ≥5/h, 74% for AHI ≥15/h) to be useful in a clinical setting, whereas the specificity was relatively good (66% and 61%, respectively). The sensitivity and specificity values of the Berlin questionnaire fell between those of the STOP-Bang questionnaire and the SA-SDQ.

Conclusion

The STOP-Bang questionnaire may be useful for screening OSA in a sleep clinic setting, but its specificity is lower than the acceptable level for this purpose. A new screening questionnaire with a high sensitivity and acceptable specificity is therefore needed in a sleep clinic setting.     

Effect of expiratory positive airway pressure on sleep disordered breathing

STUDY OBJECTIVES: We sought to determine the effect of expiratory positive airway pressure on end expiratory lung volume (EELV) and sleep disordered breathing in obstructive sleep apnea patients. DESIGN: Observational physiology study PARTICIPANTS: We studied 10 OSA patients during sleep wearing a facial mask. We recorded 1 hour of NREM sleep without treatment (baseline) and 1 hour with 10 cm H2O EPAP in random order, while measuring EELV and breathing pattern. RESULTS: The mean EELV change between baseline and EPAP was only 13.3 mL (range 2-25 mL). Expiratory time was significantly increased with EPAP compared to baseline 2.64 +/- 0.54 vs 2.16 +/- 0.64 sec (P = 0.002). Total respiratory time was longer with EPAP than at baseline 4.44 +/- 1.47 sec vs 3.73 +/- 0.88 sec (P = 0.3), and minute ventilation was lower with EPAP vs baseline 7.9 +/- 4.17 L/min vs 9.05 +/- 2.85 L/min (P = 0.3). For baseline (no treatment) and EPAP respectively, the mean apnea+hypopnea index (AHI) was 62.6 +/- 28.7 and 56.8 +/- 30.3 events per hour (P = 0.4). CONCLUSION: In OSA patients during sleep, the application of 10 cm H2O EPAP led to prolongation of expiratory time with only marginal increases in FRC. These findings suggest important mechanisms exist to avoid hyperinflation during sleep.     

Polysomnographic and Health-related Quality of Life Correlates of Restless Legs Syndrome in the Sleep Heart Health Study

Study Objectives:

Sleep disturbance is the primary clinical morbidity of restless legs syndrome (RLS). To date, sleep disturbance in RLS has been measured in (1) clinical samples with polysomnography (PSG) or (2) population-based samples by self-report. The objective of this study was to analyze sleep by PSG in a population-based sample with symptoms of RLS.

Design:

Cross-sectional observational study

Setting:

Community-based

Participants:

3433 older men and women

Interventions:

None

Measurements and Results:

RLS was evaluated using an 8-item self-administered questionnaire based on NIH diagnostic criteria and required symptoms occurring ≥ five times per month and associated with at least moderate distress. Health-related quality of life (HRQOL) was determined using the SF-36. Unattended, in-home PSG was performed. Data were assessed using general linear models with adjustment for demographic, health-related variables, and apnea-hypopnea index (AHI). Subjects with RLS had longer adjusted mean sleep latency (39.8 vs 26.4 min, P < 0.0001) and higher arousal index (20.1 vs 18.0, P = 0.0145) than those without RLS. Sleep latency increased progressively as the frequency of RLS symptoms increased from 5-15 days per month to 6-7 days per week. No differences in sleep stage percentages were observed between participants with and without RLS. Subjects with RLS also reported poorer HRQOL in all physical domains as well as in the Mental Health and Vitality domains.

Conclusions:

These novel PSG data from a nonclinical, community-based sample of individuals with RLS document sleep disturbance in the home even in individuals with intermittent symptoms.

Citation:

Winkelman JW; Redline S; Baldwin CM; Resnick HE; Newman AB; Gottlieb DJ. Polysomnographic and health-related quality of life correlates of restless legs syndrome in the sleep heart health study. SLEEP 2009;32(6):772-778.     

Sleep in overweight adolescents: shorter sleep, poorer sleep quality, sleepiness, and sleep-disordered breathing

OBJECTIVE: To document the sleep of overweight adolescents and to explore the degree to which weight-related sleep pathology might account for diminished psychosocial outcome. METHODS: Sixty children aged 10-16.9 from a weight-management clinic were compared to 22 healthy controls using comprehensive actigraphic, polysomnographic, and parent- and self-report questionnaire assessments. RESULTS: Overweight participants averaged more symptoms of sleep-disordered breathing, later sleep onset, shorter sleep time, and more disrupted sleep than controls. Although the groups did not differ in self-reported sleep habits, multiple concerns were reported by parents of overweight participants, including daytime sleepiness, parasomnias, and inadequate sleep. Group differences in academic grades and depressive symptoms were at least partially accounted for by short sleep and daytime sleepiness. CONCLUSIONS: Excessive weight is associated with an increased risk of sleep problems. There is a need for further research in this area and for clinicians who work with overweight children to evaluate their sleep.     

Behavioral control of abnormal breathing in sleep

Behavioral control of abnormal breathing in sleep was studied to determine if an intervention procedure could reduce apnea duration and also SaO ₂ (blood oxygen) desaturation levels. Sleep apnea patients (n=11) were instructed while awake that tones would be presented in sleep whenever an apnea event occurred. They were told to breathe deeply to the tones and were given practice in doing so. Intervention and nonintervention hours alternated across 2 nights following 2 baseline nights. As expected, during the intervention hours, the duration but not the frequency of apneic events was reduced. The procedure also resulted in higher SaO ₂ levels during the intervention hours. Daytime sleepiness was not greater following intervention but sleep staging effects were observed. The results are sufficiently promising to warrant additional research.This research was supported by NIH Grants 2 HL 27149-84 and HL 34125 entitled Behavioral Control of Respiration in Sleep.     

不同性别OSAHS患者的睡眠质量对血压的影响

目的 探讨不同性别的OSAHS患者的睡眠质量对血压的影响。方法 选择2014年5月~2017年12月我院通过整夜多导睡眠图监测确诊为OSAHS的患者158例,将以上患者依据分为高血压组53例和正常血压组105例,高血压组进一步分为高收缩压组33例,高舒张压组43例。比较各组男性患者与女性患者的AHI指数,睡眠质量参数与血压的关系。结果 相较于女性,男性患者的AHI指数能预测高血压组和高舒张压组（P＜0.05）;睡眠质量和高AHI之间的相关性,男性远高于女性（P＜0.05）,而没有AHI的影响,睡眠质量与男女的血压之间无显著关联（P＞0.05）。结论 男性患者比女性患者的舒张压更高,睡眠质量更差,这可能是引起男性OSAHS患者的舒张压升高的原因。     

Effect of hypercapnia on sleep and breathing in unanesthetized cats

OBJECTIVES: In this study, we looked at the effect of hypercapnia on sleep architecture and breathing. We characterized the effect of hypercapnia on duration, frequency, and latency of NREM and REM sleep. We described state-specific patterns of breathing as well. This study is relevant to understand possible treatments for sleep disordered breathing. METHODS: Four cats were studied during 3-hour sessions while breathing 0%, 2%, 4%, and 6% CO2 in room air. Each animal was studied 4 days per week for a period of 4 weeks. The animals breathed through a tube inserted into the trachea via a surgically created fistula. Respiration was measured using pneumotachography, and brain activity was recorded from implanted electrodes to discriminate states of sleep and wakefulness. RESULTS: Two percent inspired CO2 increased sleep duration and decreased time awake. On the other hand, 6% CO2 induced a worsening of sleep parameters: the duration of wakefulness increased by 24.2%. As a response to hypercapnia, tidal volume (V(T)), minute ventilation (V(E)), and respiratory effort (V(T)/T(I)) increased proportionally in all states with increasing levels of CO2. With 6% CO2, breathing tended to become similar in all states of consciousness. All breathing parameters converged towards a common value independently of the states. CONCLUSION: We conclude that a mild hypercapnic stimulus can stimulate both breathing and sleep, and it may be useful in treatment of sleep disordered breathing.     

阻塞性睡眠呼吸暂停低通气综合征患者认知功能和生活质量的关系

目的:评估阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者生活质量和认知功能状况,探讨其与多导睡眠监测图(PSG)主要指标的关系.方法:选择2006年7月至2007年4月在兰州大学第一医院就诊经PSG确诊的62例OSAHS患者和32例非OSAHS患者(对照组),用生活质量自评量表、简易智能精神状态量表、Epworth嗜睡量表(ESS)进行评估.结果:OSAHS组生活质量、认知功能评分均低于对照组(63.9±14.7/78.8±4.5、24.6±2.0/27.1±1.3,P均＜0.001);生活质量与呼吸紊乱指数(AHI)、ESS呈负相关(r=-0.52、-0.39,P均＜0.01),与平均血氧饱和度、最低血氧饱和度呈正相关(r=0.28、0.26,P均＜0.05);认知功能与AHI和ESS呈负相关(r=-O.86、-0.51,P均＜0.001),与平均血氧饱和度、最低血氧饱和度正相关(r=0.36、0.60,P均＜0.01);生活质量与认知功能呈正相关(r=0.54,P＜0.01).结论:OSAHS患者中生活质量和认知功能明显下降,二者存在相关关系.     

血清同型半胱氨酸水平在阻塞性睡眠呼吸暂停低通气综合征和冠心病患者中的变化及其作用

目的:观察血清同型半胱氨酸(Hcy)水平在阻塞性睡眠呼吸暂停低通气综合征(OSHAS)及冠心病(CHD)患者中的变化和作用。方法:收集临床确诊CHD、OSAHS、CHD+OSAHS患者各30例,分别为CHD组、OSAHS组和CHD+OSAHS组。平行检测各组血清Hcy水平及睡眠呼吸监测指标:呼吸暂停低通气指数(AHI)、夜间最低血氧饱和度(SaO2)及平均SaO2,比较各组Hcy水平的差异以及Hcy水平与睡眠呼吸监测指标的相关性。并与30例体检健康者(健康对照组)对比分析。结果:(1)血清Hcy水平:三病例组明显高于健康对照组(P0.01),CHD+OSAHS组明显高于CHD组和OSAHS组(P0.01),CHD组与OSAHS组比较,差异无统计学意义(P0.05)。(2)病例组血清Hcy水平与AHI呈正相关(r=0.64,P0.01),与夜间平均SaO2和夜间最低SaO2均呈负相关(r分别为-0.64、-0.65,P0.01)。结论:血清Hcy水平升高与OSAHS患者SaO2减低有关,可能有利于CHD的发生与发展。     

Longitudinal association of sleep-disordered breathing and nondipping of nocturnal blood pressure in the Wisconsin Sleep Cohort Study

STUDY OBJECTIVES: The association of sleep-disordered breathing (SDB) and blunting of normal nocturnal lowering of blood pressure (BP) (nondipping) has only been examined cross-sectionally. The purpose of this study is to investigate whether SDB is prospectively associated with nondipping. METHODS: The longitudinal association between SDB and incident nondipping was examined in a subsample of 328 adults enrolled in the Wisconsin Sleep Cohort Study who completed 2 or more 24-hour ambulatory BP studies over an average of 7.2 years of follow-up. SDB identified by baseline in-laboratory polysomnography was defined by apnea-hypopnea index (AHI) categories. Systolic and diastolic nondipping was defined by systolic and diastolic sleep-wake BP ratios > 0.9. All models were adjusted for age, sex, body mass index at baseline and follow-up, smoking, alcohol consumption, hypertension, sleep time, length of follow-up time, and antihypertensive medication use. RESULTS: There was a dose-response increased odds of developing systolic nondipping in participants with SDB. The adjusted odds ratios (95% confidence interval) of incident systolic nondipping for baseline AHI 5 to < 15 and AHI > or = 15, versus AHI < 5, were 3.1 (1.3-7.7) and 4.4 (1.2-16.3), respectively (P trend = 0.006). The adjusted odds ratios (95% confidence interval) of incident diastolic nondipping for corresponding SDB categories were not statistically significant: 2.0 (0.8-5.6) and 1.3 (0.2-7.1). CONCLUSIONS: Our longitudinal findings of a dose-response increase in development of systolic nondipping of BP with severity of SDB at baseline in a population-based sample provide evidence consistent with a causal link. Nocturnal systolic nondipping may be a mechanism by which SDB contributes to increased cardiovascular disease.     

阻塞性睡眠呼吸暂停综合征小型猪模型实验研究

以间歇性低压低氧方法建立阻塞性睡眠呼吸暂停综合征(Obstructivesleepapneasyndrome,OSAS)小型猪模型。8只小型猪编号后随机分为A、B、C组。A为对照组,置于双室低压氧仓二室,维持海平面压力;B、C组置于双室低压氧仓一室,仓内压力约53.9KPa、氧浓度10%~11.2%。3组每天均入仓6h。第13d处死B组,A、C组第23d同时处死。各组进仓前和处死前均行咽部CT扫描、口咽部呼吸压力、血氧饱和度检查;处死后取咽部组织行病理检查。咽部CT扫描示,咽部舌骨水平咽后壁厚度和侧壁厚度,进仓第13d(8.8±1.1vs6.5±0.6,8.1±0.2vs6.3±0.6)和第23d(9.2±1.2vs6.3±0.7,8.9±0.7vs6.4±0.5)均较进仓前有增加(P<0.05)。舌骨水平左右径和软腭水平前后径进仓第13d(7.6±1.4vs9.7±1.4,3.8±1.1vs6.5±1.3)和第23d(6.4±1.6vs9.3±1.5,4.3±0.9vs5.9±0.8)均较进仓前减小(P<0.05)。舌骨后区前后径进仓第23d后较进仓前减小(3.7±0.9VS6.4±0.6,P<0.05)。进仓第23d口咽呼吸压力(0.0755Mv)较进仓前(0.0658Mv)明显增大(P<0.05),而第13d(0.063Mv)较进仓前变化不明显。血氧饱和度进仓第13d(87%)和第23d(88.5%)均较进仓前(96.3%)明显减小(P<0.05)。病理变化:A组:咽部黏膜为复层扁平上皮,黏膜下层薄,肌层横纹清、肌间脂肪少。B组:咽部上皮组织增生伴角化,黏膜下层水肿纤维组织增生,肌层厚横纹不清、肌间脂肪灶性浸润;C组较B组病理变化程度加重。提示:间歇性低压低氧,使小型猪咽腔组织结构和力学特性发生类似OSAS病人的变化,本研究建立的OSAS小型猪模型,能用于人OSAS的进一步研究。     

无创经皮电刺激仪治疗OSAS的实验研究和临床疗效

研究采用经皮双向电流脉冲刺激舌下颏舌肌作为治疗阻塞性睡眠呼吸暂停综合征(O bstructive sleepapnea syndrom e,O SA S)的一种新方法。采用多导睡眠图同步监测患者,当发生睡眠呼吸暂停时及时给予最佳参数的电刺激,使得以颏舌肌为主的上气道扩张肌促使舌体向前运动,扩大舌咽气道,降低上气道阻力,改善夜间低氧血症,改善睡眠结构。临床疗效结果表明,22名O SA S患者经我们治疗后显效17名,好转2名,无效3名,有效率77.27%。初步证明这是一种的治疗O SA S的新方法。     

Sleep‐disordered breathing in children is associated with impairment of sleep stage‐specific shift of cardiac autonomic modulation

We examined the effects of sleep stages and sleep‐disordered breathing (SDB) on autonomic modulation in 700 children. Apnea hypopnea index (AHI) during one 9 h night‐time polysomnography was used to define SDB. Sleep stage‐specific autonomic modulation was measured by heart rate variability (HRV) analysis of the first available 5 min RR intervals from each sleep stage. The mean [standard deviation (SD)] age was 112 (21) months (49% male and 25% non‐Caucasian). The average AHI was 0.79 (SD = 1.03) h^?1, while 73.0%, 25.8% and 1.2% of children had AHI <1 (no SDB), 1–5 (mild SDB) and ≥5 (moderate SDB), respectively. In the no SDB group, the high frequency (HF) and root mean square SD (RMSSD) increased significantly from wake to Stage 2 and slow wave sleep (SWS), and then decreased dramatically when shifting into rapid eye movement (REM) sleep. In the moderate SDB group, the pattern of HRV shift was similar to that of no SDB. However, the decreases in HF and RMSSD from SWS to REM were more pronounced in moderate SDB children [between‐group differences in HF (?24% in moderate SDB versus ?10% in no SDB) and RMSSD (?27% versus ?12%) were significant (P < 0.05)]. The REM stage HF is significantly lower in the moderate SDB group compared to the no SDB group [mean (standard error): 4.49 (0.43) versus 5.80 (0.05) ms², respectively, P < 0.05]. Conclusions are that autonomic modulation shifts significantly towards higher parasympathetic modulation from wake to non‐rapid eye movement sleep, and reverses to a less parasympathetic modulation during REM sleep. However, the autonomic modulation is impaired among children with moderate SDB in the directions of more reduction in parasympathetic modulation from SWS to REM sleep and significantly weaker parasympathetic modulation in REM sleep, which may lead to higher arrhythmia vulnerability, especially during REM sleep.