Showing papers on "Polysomnography published in 2002"

Predictors of sleep-disordered breathing in community-dwelling adults: the Sleep Heart Health Study.

Abstract: Background Sleep-disordered breathing (SDB) is common, but largely undiagnosed in the general population. Information on demographic patterns of SDB occurrence and its predictive factors in the general population is needed to target high-risk groups that may benefit from diagnosis. Methods The sample comprised 5615 community-dwelling men and women aged between 40 and 98 years who were enrolled in the Sleep Heart Health Study. Data were collected by questionnaire, clinical examinations, and in-home polysomnography. Sleep-disordered breathing status was based on the average number of apnea and hypopnea episodes per hour of sleep (apnea-hypopnea index [AHI]). We used multiple logistic regression modeling to estimate cross-sectional associations of selected participant characteristics with SDB defined by an AHI of 15 or greater. Results Male sex, age, body mass index, neck girth, snoring, and repeated breathing pause frequency were independent, significant correlates of an AHI of 15 or greater. People reporting habitual snoring, loud snoring, and frequent breathing pauses were 3 to 4 times more likely to have an AHI of 15 or greater vs an AHI less than 15, but there were weaker associations for other factors with an AHI of 15 or greater. The odds ratios (95% confidence interval) for an AHI of 15 or greater vs an AHI less than 15 were 1.6 and 1.5, respectively, for 1-SD increments in body mass index and neck girth. As age increased, the magnitude of associations for SDB and body habitus, snoring, and breathing pauses decreased. Conclusions A significant proportion of occult SDB in the general population would be missed if screening or case finding were based solely on increased body habitus or male sex. Breathing pauses and obesity may be particularly insensitive for identifying SDB in older people. A better understanding of predictive factors for SDB, particularly in older adults, is needed.

Obstructive sleep apnea is independently associated with insulin resistance.

Abstract: Epidemiological studies have implicated obstructive sleep apnea (OSA) as an independent comorbid factor in cardiovascular and cerebrovascular diseases. It is postulated that recurrent episodes of occlusion of upper airways during sleep result in pathophysiological changes that may predispose to vascular diseases. Insulin resistance is a known risk factor for atherosclerosis, and we postulate that OSA represents a stress that promotes insulin resistance, hence atherogenesis. This study investigated the relationship between sleep-disordered breathing and insulin resistance, indicated by fasting serum insulin level and insulin resistance index based on the homeostasis model assessment method (HOMA-IR). A total of 270 consecutive subjects (197 male) who were referred for polysomnography and who did not have known diabetes mellitus were included, and 185 were documented to have OSA defined as an apnea–hypopnea index (AHI) ⩾ 5. OSA subjects were more insulin resistant, as indicated by higher levels of fasting s...

The role of cerebrospinal fluid hypocretin measurement in the diagnosis of narcolepsy and other hypersomnias.

Abstract: Context Narcolepsy, a neurological disorder affecting 1 in 2000 individuals, is associated with HLA-DQB1*0602 and low cerebrospinal fluid (CSF) hypocretin (orexin) levels. Objectives To delineate the spectrum of the hypocretin deficiency syndrome and to establish CSF hypocretin-1 measurements as a diagnostic tool for narcolepsy. Design Diagnosis, HLA-DQ, clinical data, the multiple sleep latency test (MSLT), and CSF hypocretin-1 were studied in a case series of patients with sleep disorders from 1999 to 2002. Signal detection analysis was used to determine the CSF hypocretin-1 levels best predictive for International Classification of Sleep Disorders (ICSD)–defined narcolepsy (blinded criterion standard). Clinical and demographic features were compared in narcoleptic subjects with and without low CSF hypocretin-1 levels. Setting Sleep disorder and neurology clinics in the United States and Europe, with biological testing performed at Stanford University, Stanford, Calif. Participants There were 274 patients with narcolepsy; hypersomnia; obstructive sleep apnea; restless legs syndrome; insomnia; and atypical hypersomnia cases such as familial cases, narcolepsy without cataplexy or without HLA-DQB1*0602, recurrent hypersomnias, and symptomatic cases (eg, Parkinson disease, depression, Prader-Willi syndrome, Niemann-Pick disease type C). The subject group also included 296 controls (healthy and with neurological disorders). Intervention Venopuncture for HLA typing, lumbar puncture for CSF analysis, primary diagnosis using the International Classification of Sleep Disorders, Stanford Sleep Inventory for evaluation of narcolepsy, and sleep recording studies. Main Outcome Measures Diagnostic threshold for CSF hypocretin-1, HLA-DQB1*0602 positivity, and clinical and polysomnographic features. Results HLA-DQB1*0602 frequency was increased in narcolepsy with typical cataplexy (93% vs 17% in controls), narcolepsy without cataplexy (56%), and in essential hypersomnia (52%). Hypocretin-1 levels below 110 pg/mL were diagnostic for narcolepsy. Values above 200 pg/mL were considered normal. Most subjects with low levels were HLA-DQB1*0602–positive narcolepsy-cataplexy patients. These patients did not always have abnormal MSLT. Rare subjects without cataplexy, DQB1*0602, and/or with secondary narcolepsy had low levels. Ten subjects with hypersomnia had intermediate levels, 7 with narcolepsy (often HLA negative, of secondary nature, and/or with atypical cataplexy or no cataplexy), and 1 with periodic hypersomnia. Healthy controls and subjects with other sleep disorders all had normal levels. Neurological subjects had generally normal levels (n = 194). Intermediate (n = 30) and low (n = 3) levels were observed in various acute neuropathologic conditions. Conclusions Narcolepsy-cataplexy with hypocretin deficiency is a genuine disease entity. Measuring CSF hypocretin-1 is a definitive diagnostic test, provided that it is interpreted within the clinical context. It may be most useful in cases with cataplexy and when the MSLT is difficult to interpret (ie, in subjects already treated with psychoactive drugs or with other concurrent sleep disorders).

Sleep, neurobehavioral functioning, and behavior problems in school-age children

Abstract: The aim of this study was to examine the associations between sleep and neurobehavioral functioning (NBF) in school-age children. These variables were assessed for 135 unreferred, healthy school children (69 boys and 66 girls), from second-, fourth-, and sixth-grade classes. Objective assessment methods were used on the participants in their regular home settings. Sleep was monitored using actigraphy for 5 consecutive nights; and NBF was assessed using a computerized neurobehavioral evaluation system, administered twice, at different times of the day. Significant correlations between sleep-quality measures and NBF measures were found, particularly in the younger age group. Children with fragmented sleep were characterized by lower performance on NBF measures, particularly those associated with more complex tasks such as a continuous performance test and a symbol-digit substitution test. These children also had higher rates of behavior problems as reported by their parents on the Child Behavior Checklist. These results highlight the association between sleep quality, NBF, and behavior regulation in child development; and raise important questions about the origins of these associations and their developmental and clinical significance.

Clinical practice guideline: Diagnosis and management of childhood obstructive sleep apnea syndrome

Abstract: To the Editor. — I have major reservations in respect to the recent clinical practice guideline on obstructive sleep apnea syndrome (OSAS).1 Although it is important to alert pediatricians to the existence of this condition, the ramifications of following the guideline do not appear to have been given adequate consideration. The authors signed letters stating they did not have a conflict of interest. I assume this means they do not run polysomnography (PSG) labs, as an obvious consequence of the report will be a markedly increased demand for their use. One problem concerns children with primary snoring (PS). This can be seen, according to the report, in up to 12% of preschool-aged children. Furthermore, there is apparently no way to rule out OSAS in these children, without doing PSG. The unmistakable conclusion, therefore, is that up to 12% of preschool-aged children should be undergoing PSG. Do other pediatricians find this concept as ludicrous as I do? A second issue concerns those children with mild OSAS, mild meaning that they are not demonstrating obvious problems such as daytime somnolence or pulmonary hypertension. These children are diagnosed when their sleep studies are found to be abnormal (ie, at the tail end of the distribution curve). The guideline indicates, in one sentence in the section on research recommendations, that the natural history of these children is not known. That did not stop the committee from recommending that these children undergo adenotonsillectomy, however, even though it is not known whether mild OSAS is an actual disease or merely a statistical finding. In summary, I believe the guideline to be poorly thought out, and it …

REM sleep behavior disorder and REM sleep without atonia in Parkinson's disease.

Abstract: Objective: To determine the frequency of REM sleep behavior disorder (RBD) among patients with PD using both history and polysomnography (PSG) recordings and to further study REM sleep muscle atonia in PD. Background: The reported occurrence of RBD in PD varies from 15 to 47%. However, no study has estimated the frequency of RBD using PSG recordings or analyzed in detail the characteristics of REM sleep muscle atonia in a large group of unselected patients with PD. Methods: Consecutive patients with PD (n = 33) and healthy control subjects (n = 16) were studied. Each subject underwent a structured clinical interview and PSG recording. REM sleep was scored using a method that allows the scoring of REM sleep without atonia. Results: One third of patients with PD met the diagnostic criteria of RBD based on PSG recordings. Only one half of these cases would have been detected by history. Nineteen (58%) of 33 patients with PD but only 1 of 16 control subjects had REM sleep without atonia. Of these 19 patients with PD, 8 (42%) did not present with behavioral manifestations of RBD, and their cases may represent preclinical forms of RBD associated with PD. Moreover, the percentage of time spent with muscle atonia during REM sleep was lower among patients with PD than among healthy control subjects (60.1% vs 93.2%; p = 0.003). Conclusions: RBD and REM sleep without atonia are frequent in PD as shown by PSG recordings.

Technical Report: Diagnosis and Management of Childhood Obstructive Sleep Apnea Syndrome

Abstract: Objective. This technical report describes the procedures involved in developing the recommendations of the Subcommittee on Obstructive Sleep Apnea Syndrome in children. The group of primary interest for this report was otherwise healthy children older than 1 year who might have adenotonsillar hypertrophy or obesity as underlying risk factors of obstructive sleep apnea syndrome (OSAS). The goals of the committee were to enhance the primary care clinician’s ability to recognize OSAS, identify the most appropriate procedure for diagnosis of OSAS, identify risks associated with pediatric OSAS, and evaluate management options for OSAS. Methods. A literature search was initially conducted for 2the years 1966–1999 and then updated to include 2000. The search was limited to English language literature concerning children older than 2 and younger than 18 years. Titles and abstracts were reviewed for relevance, and committee members reviewed in detail any possibly appropriate articles to determine eligibility for inclusion. Additional articles were obtained by a review of literature and committee members’ files. Committee members compiled evidence tables and met to review and discuss the literature that was collected. Results. A total of 2115 titles were reviewed, of which 113 provided relevant original data for analysis. These articles were mainly case series and cross-sectional studies; overall, very few methodologically strong cohort studies or randomized, controlled trials concerning OSAS have been published. In addition, a minority of studies satisfactorily differentiated primary snoring from true OSAS. Reports of the prevalence of habitual snoring in children ranged from 3.2% to 12.1%, and estimates of OSAS ranged from 0.7% to 10.3%; these studies were too heterogeneous for data pooling. Children with sleep-disordered breathing are at increased risk for hyperactivity and learning problems. The combined odds ratio for neurobehavioral abnormalities in snoring children compared with controls is 2.93 (95% confidence interval: 2.23–3.83). A number of case series have documented decreased somatic growth in children with OSAS; right ventricular dysfunction and systemic hypertension also have been reported in children with OSAS. However, the risk growth and cardiovascular problems cannot be quantified from the published literature. Overnight polysomnography (PSG) is recognized as the gold standard for diagnosis of OSAS, and there are currently no satisfactory alternatives. The diagnostic accuracy of symptom questionnaires and other purely clinical approaches is low. Pulse oximetry appears to be specific but insensitive. Other methods, including audiotaping or videotaping and nap or home overnight PSG, remain investigational. Adenotonsillectomy is curative in 75% to 100% of children with OSAS, including those who are obese. Up to 27% of children undergoing adenotonsillectomy for OSAS have postoperative respiratory complications, but estimates are varied. Risk factors for persistent OSAS after adenotonsillectomy include continued snoring and a high apnea-hypopnea index on the preoperative PSG. Conclusions. OSAS is common in children and is associated with significant sequelae. Overnight PSG is currently the only reliable diagnostic modality that can differentiate OSAS from primary snoring. However, the PSG criteria for OSAS have not been definitively validated, and it is not clear that primary snoring without PSG-defined OSAS is benign. Adenotonsillectomy is the first-line treatment for OSAS but requires careful postoperative monitoring because of the high risk of respiratory complications. Adenotonsillectomy is usually curative, but children with persistent snoring (and perhaps with severely abnormal preoperative PSG results) should have PSG repeated postoperatively.

Parkinson’s disease and sleepiness An integral part of PD

Abstract: Objective: To investigate the potential causes of excessive daytime sleepiness in patients with PD—poor sleep quality, abnormal sleep–wakefulness control, and treatment with dopaminergic agents. Methods: The authors performed night-time polysomnography and daytime multiple sleep latency tests in 54 consecutive levodopa-treated patients with PD referred for sleepiness, 27 of whom were also receiving dopaminergic agonists. Results: Sleep latency was 6.3 ± 0.6 minutes (normal >8 minutes), and the Epworth Sleepiness score was 14.3 ± 4.1 (normal 15/h; range 15.1 to 50.0). Severity of sleepiness was weakly correlated with Epworth Sleepiness score ( r = −0.34) and daily dose of levodopa ( r = 0.30) but not with dopamine-agonist treatment, age, disease duration, parkinsonian motor disability, total sleep time, periodic leg movement, apnea–hypopnea, or arousal indices. Conclusions: In patients with PD preselected for sleepiness, severity of sleepiness was not dependent on nocturnal sleep abnormalities, motor and cognitive impairment, or antiparkinsonian treatment. The results suggest that sleepiness—sudden onset of sleep—does not result from pharmacotherapy but is related to the pathology of PD.

Treatment of restless legs syndrome with gabapentin: A double-blind, cross-over study

Abstract: Objective: To assess the effects of gabapentin on sensory and motor symptoms in patients with restless legs syndrome (RLS). Methods: Patients with RLS (22 idiopathic, 2 secondary to iron deficiency) were randomized and treated for 6 weeks with either gabapentin or placebo. After a 1-week washout they crossed over to the alternative treatment for 6 weeks. Patients were rated at baseline and at scheduled intervals by the RLS Rating Scale, Clinical Global Impression, pain analogue scale, and Pittsburgh Sleep Quality Index. At the end of each treatment period, all-night polysomnography was performed. Results: Compared to placebo, gabapentin was associated with reduced symptoms on all rating scales. In addition, sleep studies showed a significantly reduced periodic leg movements during sleep (PLMS) index and improved sleep architecture (increased total sleep time, sleep efficiency, and slow wave sleep, and decreased stage 1 sleep). Patients whose symptoms included pain benefited most from gabapentin. The mean effective dosage at the end of the 6-week treatment period was 1,855 mg, although therapeutic effects were already observed at the end of week 4 (1,391 mg). Conclusions: Gabapentin improves sensory and motor symptoms in RLS and also improves sleep architecture and PLMS.

Benefit of atrial pacing in sleep apnea syndrome.

Abstract: Background Many patients with sleep apnea syndrome have nocturnal bradycardia, paroxysmal tachyarrhythmias, or both, which can be prevented by permanent atrial pacing. We evaluated the effect of using cardiac pacing to increase the heart rate during sleep in patients with sleep apnea syndrome. Methods We studied 15 patients (11 men and 4 women; mean [±SD] age, 69±9 years) with central or obstructive sleep apnea who had received permanent atrial-synchronous ventricular pacemakers for symptomatic sinus bradycardia. All patients underwent three polysomnographic evaluations on consecutive nights, the first night for base-line evaluation and then, in random order, one night in spontaneous rhythm and one in dual-chamber pacing mode with atrial overdrive (basic rate, 15 beats per minute faster than the mean nocturnal sinus rate). The total duration and number of episodes of central or obstructive sleep apnea or hypopnea were analyzed and compared. Results The mean 24-hour sinus rate during spontaneous rhythm was...

REM Sleep and the Early Development of Posttraumatic Stress Disorder

Abstract: Objective: The potential for chronicity and treatment resistance once posttraumatic stress disorder (PTSD) has become established has stimulated interest in understanding the early pathogenesis of the disorder. Arousal regulation and memory consolidation appear to be important in determining the development of PTSD; both are functions of sleep. Sleep findings from patients with chronic PTSD are complex and somewhat contradictory, and data from the acute phase are quite limited. The aim of the present study was to obtain polysomnographic recordings during an acute period after life-threatening experiences and injury and to relate measures of sleep duration and maintenance and the timing, intensity, and continuity of REM sleep to the early development of PTSD. Method: Twenty-one injured subjects meeting study criteria received at least one polysomnographic recording close to the time of medical/surgical stabilization and within a month of injury. PTSD symptoms were assessed concurrently and 6 weeks later. Sleep measures were compared among injured subjects with and without significant PTSD symptoms at follow-up and 10 noninjured comparison subjects and were also correlated with PTSD severity. Results: There was more wake time after the onset of sleep in injured, trauma-exposed patients than in noninjured comparison subjects. Development of PTSD symptoms was associated with shorter average duration of REM sleep before a stage change and more periods of REM sleep. Conclusions: The development of PTSD symptoms after traumatic injury is associated with a more fragmented pattern of REM sleep.

Clinical practice. Obstructive sleep apnea

Abstract: A 43-year-old man presents with heavy snoring; his bed partner reports that he sometimes stops breathing while he sleeps. He has hypertension controlled by medication but is otherwise healthy. He admits to feeling sleepy at times when he drives, although he has not had any motor vehicle accidents. His body-mass index is 33, and he has a large neck circumference (46 cm). How should he be evaluated and treated?

A Randomized Controlled Trial of Continuous Positive Airway Pressure in Mild Obstructive Sleep Apnea

Abstract: A common clinical dilemma faced by sleep physicians is in deciding the level of severity at which patients with obstructive sleep apnea (OSA) should be treated. There is particular uncertainty about the need for, and the effectiveness of, treatment in mild cases. To help define the role of nasal continuous positive airway pressure (CPAP) treatment in mild OSA we undertook a randomized controlled cross-over trial of CPAP in patients with an apnea- hypopnea index (AHI) of 5 - 30 (mean, 12.9 +/- 6.3 SD). Twenty-four-hour blood pressure and neurobehavioral function were measured at baseline, after 8 wk of treatment with CPAP, and after 8 wk of treatment with an oral placebo tablet. Twenty-eight of 42 patients enrolled in the study completed both treatment arms. Baseline characteristics were not different between those who completed the study and those who did not complete the study. Patients used CPAP for a mean (SD) of 3.53 (2.13) h per night and the mean AHI on the night of CPAP implementation was 4.24 (2.9). Nasal CPAP improved self-reported symptoms of OSA, including snoring, restless sleep, daytime sleepiness, and irritability (in-house questionnaire), more than did placebo, but did not improve objective (Multiple Sleep Latency Test) or subjective (Epworth Sleepiness Scale) measures of daytime sleepiness. We found no benefit of CPAP over placebo in any tests of neurobehavioral function, generic SF-36 (36-item Short Form Medical Outcomes Survey) or sleep-specific (Functional Outcomes of Sleep Questionnaire) quality of life questionnaires, mood score (Profile of Moods States and Beck Depression Index), or 24-h blood pressure. However, the placebo tablet resulted in a significant improvement in a wide range of functional variables compared with baseline. This placebo effect may account for some of the treatment responses to CPAP observed previously in patients with mild OSA.

Oral appliance therapy improves symptoms in obstructive sleep apnea: a randomized, controlled trial.

Abstract: The aim of this study was to evaluate the effect of a mandibular advancement splint (MAS) on daytime sleepiness and a range of other symptoms in obstructive sleep apnea (OSA). Using a randomized crossover design, patients received 4 weeks of treatment with MAS and a control device (inactive oral appliance), with an intervening 1-week washout. At the end of each treatment period, patients were reassessed by questionnaire, polysomnography, and multiple sleep latency test. Fifty-nine men and 14 women with a mean (± SD) age of 48 ± 11 years and proven OSA experienced a significantly improved mean (± SEM) sleep latency on the multiple sleep latency test (10.3 ± 0.5 versus 9.1 ± 0.5 minutes, p = 0.01) and Epworth sleepiness scale score (7 ± 1 versus 9 ± 1, p < 0.0001) with the MAS compared with the control device after 4 weeks. The proportion of patients with normal subjective sleepiness was significantly higher with the MAS than with the control device (82 versus 62%, p < 0.01), but this was not so for objecti...

NREM sleep EEG frequency spectral correlates of sleep complaints in primary insomnia subtypes.

Abstract: Design: We compared EEG frequency spectra from REM and NREM sleep in PPI subjects subtyped as subjective insomnia sufferers (those with relatively long total sleep time and relative underestimation of sleep time compared with PSG), and objective insomnia sufferers (those with relatively short PSG total sleep time) with EEG frequency spectra in normals. We also studied the correlation between these indices and the degree of underestimation of sleep. Further, we determined the degree to which sleep EEG indexes related to sleep complaints. Setting: Duke University Medical Center Sleep Laboratory. Participants: Normal (N=20), subjective insomnia (N=12), and objective insomnia (N=18) subjects. Interventions: N/A Measurements and Results: Lower delta and greater alpha, sigma, and beta NREM EEG activity were found in the patients with subjective insomnia but not those with objective insomnia, compared with the normal subjects. These results were robust to changes in the subtyping criteria. No effects were found for REM spectral indexes. Less delta non- REM EEG activity predicted greater deviation between subjective and PSG estimates of sleep time across all subjects. For the subjective insomnia subjects, diminished low-frequency and elevated higher frequency non- REM EEG activity was associated with their sleep complaints. Conclusions: NREM EEG frequency spectral indexes appear to be physiologic correlates of sleep complaints in patients with subjective insomnia and may reflect heightened arousal during sleep.

Randomized crossover trial of two treatments for sleep apnea/hypopnea syndrome: continuous positive airway pressure and mandibular repositioning splint

Abstract: Mandibular repositioning splints (MRSs) and continuous positive airway pressure (CPAP) are used to treat the sleep apnea/hypopnea syndrome (SAHS). There are some data suggesting that patients with milder symptoms prefer MRS, but there are few comparative data on outcomes. Therefore, we performed a randomized crossover trial of 8 weeks of CPAP and 8 weeks of MRS treatment in consecutive new outpatients diagnosed with SAHS (apnea/hypopnea index [AHI] >or= 5/hour, and >or= 2 symptoms including sleepiness). Assessments at the end of both limbs comprised home sleep study, subjective ratings of treatment value, sleepiness, symptoms, and well-being, and objective tests of sleepiness and cognition. Forty-eight of 51 recruited patients completed the trial (12 women; age [mean +/- SD], 46 +/- 9 years; Epworth 14 +/- 4; median AHI, 22/hour; interquartile ratio [IQR], 11-43/hour). Significant (p

Effect of Ventilator Mode on Sleep Quality in Critically Ill Patients

Abstract: To determine whether sleep quality is influenced by the mode of mechanical ventilation, we performed polysomnography on 11 critically ill patients. Because pressure support predisposes to central apneas in healthy subjects, we examined whether the presence of a backup rate on assist-control ventilation would decrease apnea-related arousals and improve sleep quality. Sleep fragmentation, measured as the number of arousals and awakenings, was greater during pressure support than during assist-control ventilation: 79 ± 7 versus 54 ± 7 events per hour (p = 0.02). Central apneas occurred during pressure support in six patients; heart failure was more common in these six patients than in the five patients without apneas: 83 versus 20% (p = 0.04). Among patients with central apneas, adding dead space decreased sleep fragmentation: 44 ± 6 versus 83 ± 12 arousals and awakenings per hour (p = 0.02). Changes in sleep–wakefulness state caused greater changes in breath components and end-tidal CO2 during pressure supp...

Prevalence and clinical importance of sleep apnea in the first night after cerebral infarction

Abstract: Objective To determine the prevalence of sleep apnea (SA) during the first night after hemispheric ischemic stroke and its influence on clinical presentation, course, and functional outcome at 6 months. Methods The first night after cerebral infarction onset, 50 patients underwent polysomnography (PSG) followed by oximetry during the next 24 hours. Neurologic severity and early worsening were assessed by the Scandinavian Stroke Scale and outcome by the Barthel Index. Patients were evaluated on admission, on the third day, at discharge, and at 1, 3, and 6 months. Results There were 30 males and 20 females with a mean age of 66.8 +/- 9.5 years. Latency between stroke onset and PSG was 11.6 +/- 5.3 hours. Thirty-one (62%) subjects had SA (apnea-hypopnea index [AHI] > or = 10). Of these, 23 (46%) had an AHI > or =20 and 21 (42%) an AHI > or =25. Sleep-related stroke onset occurred in 24 (48%) patients and was predicted only by an AHI > or =25 on logistic regression analysis. SA was related to early neurologic worsening and oxyhemoglobin desaturations but not to sleep history before stroke onset, infarct topography and size, neurologic severity, or functional outcome. Early neurologic worsening was found in 15 (30%) patients, and logistic regression analysis identified SA and serum glucose as its independent predictors. Conclusions SA is frequent during the first night after cerebral infarction (62%) and is associated with early neurologic worsening but not with functional outcome at 6 months. Cerebral infarction onset during sleep is associated with the presence of moderate to severe SA (AHI > or = 25).

Patterns and predictors of sleep disordered breathing in primary myopathies.

Abstract: Background: Sleep disordered breathing (SDB) is common in neuromuscular diseases but its relationship to respiratory function is poorly defined. A study was undertaken to identify distinct patterns of SDB, to clarify the relationships between SDB and lung and respiratory muscle function, and to identify daytime predictors for SDB at its onset, for SDB with continuous hypercapnic hypoventilation, and for diurnal respiratory failure. Methods: Upright and supine inspiratory vital capacity (IVC, % predicted), maximal inspiratory muscle pressure (PImax), respiratory drive (P0.1), respiratory muscle effort (P0.1/PImax), and arterial blood gas tensions were prospectively compared with polysomnography and capnometry (PtcCO2) in 42 patients with primary myopathies. Results: IVC correlated with respiratory muscle function and gas exchange by day and night. SDB evolved in three distinct patterns from REM hypopnoeas, to REM hypopnoeas with REM hypoventilation, to REM/non-REM (continuous) hypoventilation, and preceded diurnal respiratory failure. SDB correlated with IVC and PImax which yielded highly predictive thresholds for SDB onset (IVC <60%, PImax <4.5 kPa), SDB with continuous hypoventilation (IVC <40%, PImax <4.0 kPa), and SDB with diurnal respiratory failure (IVC <25%, PImax <3.5 kPa). Conclusion: Progressive ventilatory restriction in neuromuscular diseases correlates with respiratory muscle weakness and results in progressive SDB which, by pattern and severity, can be predicted from daytime lung and respiratory muscle function.

Periodic leg movements in REM sleep behavior disorder and related autonomic and EEG activation.

Abstract: Objective: To assess the frequency of periodic leg movements (PLM) in idiopathic REM sleep behavior disorder (RBD) and to analyze their polysomnographic characteristics and associated autonomic and cortical activation. Background: PLM during sleep (PLMS) and wakefulness (PLMW) are typical features of restless legs syndrome (RLS), but are also frequently observed in patients with RBD. Methods: Forty patients with idiopathic RBD underwent one night of polysomnographic recording to assess PLMS frequency. PLM features, PLMS-related cardiac activation during stage 2 sleep, and EEG changes were analyzed in 15 of these patients with RBD. Results were compared with similar data obtained in 15 sex- and age-matched patients with primary RLS. Results: Twenty-eight (70%) of 40 patients with RBD showed a PLMS index greater than 10. No between-group differences were found in sleep architecture or indexes of PLMW and PLMS during non-REM sleep, but a trend for a higher PLMS index during REM sleep was found in patients with RBD. PLM mean duration and interval in the two conditions were similar. A transient tachycardia followed by a bradycardia was observed in close association with every PLMS in both groups, but the amplitude of the cardiac activation was significantly reduced in patients with RBD. In addition, significantly fewer PLMS were associated with microarousal in this condition. Conclusions: Periodic leg movements are very common in idiopathic RBD, occurring in all stages of sleep, especially during REM sleep. In idiopathic RBD, the reduction of cardiac and EEG activation associated with PLMS suggests the presence of an impaired autonomic and cortical reactivity to internal stimuli.