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.     

Sleep apnoea in well-controlled myasthenia gravis and the effect of thymectomy

We conducted overnight polysomnographic sleep studies of 16 patients (5 men and 11 women) with clinically well-controlled myasthenia gravis (MG). The subtypes of MG were IIA (3 patients), IIB (11 patients), IV (1 patient) and V (1 patient). Twelve patients were found on polysomnography to have obstructive and/or central types of the sleep apnoeas (SA). Their mean age was 42.4, SD 16.4 years, and the mean duration of MG was 7.4, SD 6.96 years. SA was not detected in 4 patients whose mean age was 30.8, SD 10.71 years and who had manifested MG for a mean duration of only 0.9, SD 0.65 years. Thus, patients with a longer duration of MG tended to have more SA. In 9 of the 12 SA patients, polysomnographic studies were repeated following thymectomy. SA had resolved in 6 patients, but persisted in 3. These findings suggest that SA is a possible clinical manifestiation of MG and that nocturnal dysfunction of both peripheral and central colinergic systems may be involved. Received: 10 April 1996 Received in revised form: 12 September 1997 Accpeted: 1 October 1997     

Respiratory disturbances in rett syndrome: don't forget to evaluate upper airway obstruction

Rett syndrome is characterized by loss of motor and social functions, development of stereotypic hand movements, seizures, and breathing disturbances. This study evaluates the presence of overnight respiratory disturbances. Polysomnography in combination with a questionnaire (the Sleep Disturbance Scale for Children) was performed in 12 Dutch patients with Rett. Respiratory disturbances were present in all, clinically relevant in 10 (apnea hypopnea per hour 1.0-14.5). In 8 children, central apneas were present during the day often with obstructive apneas at night. In 6, obstructive sleep apnea syndrome was diagnosed, in 3 severe, with frequent oxygen desaturations. Significant respiratory complaints were present in 3 patients, all had obstructive sleep apnea syndrome. Of the 12 patients with Rett, 8 (67%) snored, and in 5 obstructive sleep apnea syndrome was present. In children, hypertrophied tonsils and adenoids are a common cause of obstructive sleep apnea syndrome, which may benefit from therapeutic intervention. We recommend performing polysomnography in patients with Rett syndrome and respiratory complaints.     

Treatment of sleep apnea syndrome in a Down syndrome patient with behavioral problems by noninvasive positive pressure ventilation: a successful case report

The use of noninvasive positive pressure ventilation (NPPV) is increasingly accepted as a treatment of respiratory problems in patients with neuromuscular disease. However, its use in mentally retarded and un-cooperative patients has not been reported. We report here the evaluation and treatment of sleep apnea in a Down syndrome patient. After recovering from a life threatening respiratory failure the patient had persistent sleep apnea syndrome. Limited examinations disclosed that he had two types of apnea; obstructive and central type apnea. Our treatment was a diet with intake restricted up to 1,000 kcal per day for the obstructive apnea, and NPPV with low dosage of oxygen for the obstructive and central apnea. With these treatments in one year's hospitalization, his quality of life was significantly improved. He has continued the treatment in the outpatient department and enjoys a better quality of life both at home and in the community. The successful treatment of this case may become an example of the more extensive use of NPPV for such respiratory problems in handicapped children and adults with behavioral problems.     

颅内肿瘤和睡眠呼吸暂停低通气综合征

目的 评估颅内肿瘤病人呼吸暂停低通气的类型以及肿瘤切除术在改善呼吸紊乱方面起的作用.方法 对30例颅内肿瘤病人(22例幕上,8例幕下)术前、术后进行睡眠呼吸检测.结果 术前平均呼吸暂停低通气指数为23.3,18例病人存在阻塞性呼吸暂停,3例病人存在阻塞性和中枢性呼吸暂停.术后平均呼吸暂停低通气指数降为9.6(P＜0.0...     

Respiratory pauses and apnea during daytime sleep in normal infants during the first year of life: longitudinal observations

Respiratory pauses (3-10 sec in duration), apnea (less than 10 sex in duration), and periodic respiration observed in thoracic respirograms were measured in 226 polysomnograms obtained on 17 normal infants during the first year of life. All subjects had one or more respiratory pauses in a majority of recordings; 35% had respiratory pauses in all recordings; 75% of respiratory pauses were associated with body movement. There is marked intersubject and even intrasubject variability in respiratory pause rates. The range of mean respiratory pause rates among subjects was 2.0 - 14.4/h, and for single recordings was 0.0 - 43.6/h. Their occurrence was directly related to the occurrence of periodic respiration. Rates were higher during REM and indeterminate sleep than during slow wave sleep. There was no significant trend toward increase or decrease in respiratory pause rate during the first year post term. Apnea occurred in only one of the 226 recordings (0.4%). Periodic respiration occurred in 8 of 17 subjects (47%), and in 25 of 226 recordings (11%). Its occurrence was unrelated to sleep stage. The following conclusions are considered valid on the basis of the data presented and reports in the literature: (1) Rates of respiratory interruption are higher before than after 40 weeks conceptional age. (2) There is considerable intersubject variability in rates of respiratory interruptions. (3) Respiratory pauses are common during sleep in normal human infants. (4) Respiratory pauses occur more frequently with movements than in their absence. (5) Respiratory pause rates are higher during REM sleep than during slow wave sleep. (6) Apneas of greater than 10-15 sec duration do occur in normal infants, but are rare. From the clinical viewpoint, respiratory pauses (less than 15 sec) of the central type, regardless of abundance, and periodic respiration cannot by themselves be used as evidence that a baby is at risk of anything. The occurrence of apneas (greater than 15 sec duration), especially if any are of the obstructive or mixed types (and perhaps respiratory pauses of the obstructive and mixed types), and/or if associated with bradycardia or decrease in oxygen saturation, indicate sleep apnea syndrome and suggest risk of sudden infant death.     

Fatigue in obstructive sleep apnea: driven by depressive symptoms instead of apnea severity?

OBJECTIVE: Obstructive sleep apnea is a common and frequently devastating illness that often includes significant fatigue. Fatigue is also a hallmark depressive symptom. The authors wondered if depressive symptoms in patients with obstructive sleep apnea would account for some of the fatigue beyond that explained by obstructive sleep apnea severity. METHOD: Sixty patients with obstructive sleep apnea-i.e., score >/=15 on the respiratory disturbance index (mean score=49; range=15-111)-underwent polysomnography and completed the Center for Epidemiological Studies Depression Scale (CES-D Scale), Profile of Mood States (POMS), and Medical Outcomes Study surveys. Data were analyzed by using hierarchical regression, with POMS fatigue score as the dependent variable (step 1, forced entry of apnea severity variables; step 2, forced entry of CES-D Scale score). RESULTS: Whereas score on the respiratory disturbance index and the percent of time oxygen saturation was <90% together accounted for 4.2% of variance in scores on the POMS fatigue scale, the CES-D Scale score accounted for 10 times the variance (i.e., an additional 42.3%) in POMS fatigue scale score. CONCLUSIONS: After obstructive sleep apnea severity was controlled, higher levels of depressive symptoms were dramatically and independently associated with greater levels of fatigue. Assessment and treatment of mood symptoms-not just treatment of the disordered breathing itself-might reduce the fatigue experienced by patients with obstructive sleep apnea.     

Therapy of obstructive sleep apnea syndrome

Symptomatology and sequelae, as well as diagnosis and therapy of the obstructive sleep apnea syndrome are discussed. The Esmarch prosthesis, which we developed for the prosthetic treatment of obstructive sleep apnea syndrome, was tested in 7 patients. Patients were polysomnographically recorded during two sequential nights with and without Esmarch prosthesis. All apnea parameters improved significantly (apnea time by 78%, apnea index by 67% of baseline values). The mean duration of the remaining apnea phases diminished by 31%. Improvement of O2 saturation of haemoglobin and O2 partial pressure in the tissue paralleled that of the apnea parameters. The severely disturbed sleep profile of the patients showed a clear tendency towards normalization. The Esmarch prosthesis is an efficient method for the treatment of the obstructive sleep apnea syndrome.     

Influence of nocturnal hypoxemia on the function of the visual tract in the course of the obstructive sleep apnea syndrome

BACKGROUND AND PURPOSE: In patients with obstructive sleep apnea (OSA) syndrome the episodes of upper airway obstruction lead to hypoxemia during sleep. The aim of the study was to establish the influence of sleep hypoxemia on the function of the visual tract in OSA patients. MATERIAL AND METHODS: The latency and amplitude of wave P100 of visual evoked potentials have been studied in 35 patients with OSA syndrome (mean apnea index 48+/-19). The diagnosis of OSA was established on the basis of continuous recordings of the respiratory function during sleep with additional full polysomnography in 17 patients. RESULTS: Mean absolute latency of P100 was longer in OSA patients than in healthy controls (117.0+/-8.8 ms vs. 104.3+/-4.6 ms, p<0.001). The differences in the amplitude of P100 were not significant (5.9+/-2.6 mV in OSA patients and 7.62+/-3.04 mV in healthy persons). In 60% of patients the latency of P100 exceeded 118 ms; in this group of patients the mean SaO2 during sleep apneas was lower than in patients with normal P100 latency (46+/-15% vs. 69+/-10%, p<0.05). Full polysomnographic studies revealed that in patients with prolonged latencies as compared with patients with normal P100 latencies there were lower: minimal SaO2 during NREM sleep (63+/-12% vs. 78+/-8%, p<0.05), as well as mean and minimal SaO2 during REM sleep (53+/-15% vs. 80+/-5% and 46+/-15% vs. 69+/-10%, p<0.05), without differences in apnea index or apnea duration. CONCLUSIONS: In patients with OSA syndrome the electrophysiological abnormalities suggesting damage of the optical tract may develop probably as a consequence of profound sleep hypoxemia.     

The Koga Hospital Center for studies on sleep: status report

Between September 1996 and January 1999 we used polysomnography (PSG) to examine 473 patients (involving a total of 662 records). The diagnosis was a sleep-related breathing disorder in 256 patients, including sleep apnea syndrome (SAS) in 194 patients, sleep hypoxicemia in 18 and insomnia in the other four. The SAS consisted of three subtypes: central apnea (CA) in 56 patients, obstructive apnea (OA) in 124 and mixed apnea (MA) in eight. The ratio of central apnea was relatively higher than the national average. Among the 473 patients, the most common complication was heart disease (133 patients) while other complications included hypertension, and respiratory and cerebrovascular diseases. Concerning the therapy for these patients, continuous positive airway pressure therapy was the most commonly applied and was effective in each type of SAS (CA, OA, MA). Other therapies included prosthetic mandibular advancement, bilevel positive airway pressure, medication and ENT operations. In Koga Hospital, there are many patients with heart disease and/or respiratory disease. We examined those patients who presented with snoring and/or apnea using PSG. Among these patients, SAS was the most common sleep disorder. The relative ratio of CA was high and the average age was higher than those with OA.     

Detection of cognitive impairment in patients with obstructive sleep apnea hypopnea syndrome using mismatch negativity

In this experiment,97 patients with obstructive sleep apnea hypopnea syndrome were divided into three groups(mild,moderate,severe) according to minimum oxygen saturation,and 35 healthy subjects were examined as controls.Cognitive function was determined using the mismatch negativity paradigm and the Montreal Cognitive Assessment.The results revealed that as the disease worsened,the mismatch negativity latency was gradually extended,and the amplitude gradually declined in patients with obstructive sleep apnea hypopnea syndrome.Importantly,mismatch negativity latency in severe patients with a persistent time of minimum oxygen saturation < 60 seconds was significantly shorter than that with a persistent time of minimum oxygen saturation > 60 seconds.Correlation analysis revealed a negative correlation between minimum oxygen saturation latency and Montreal Cognitive Assessment scores.These findings indicate that intermittent night-time hypoxemia affects mismatch negativity waveforms and Montreal Cognitive Assessment scores.As indicators for detecting the cognitive functional status of obstructive sleep apnea hypopnea syndrome patients,the sensitivity of mismatch negativity is 82.93%,the specificity is 73.33%,the accuracy rate is 81.52%,the positive predictive value is 85.00%,the negative predictive value is 70.21%,the positive likelihood ratio is 3,and the negative likelihood ratio is 0.23.These results indicate that mismatch negativity can be used as an effective tool for diagnosis of cognitive dysfunction in obstructive sleep apnea hypopnea syndrome patients.     

Characteristics of breathing abnormality in Leigh and its overlap syndromes

In this report we describe the respiratory patterns of six patients with Leigh syndrome, including two individual cases with accompanying clinical phenotypes of Alpers disease and mitochondrial encephalopathy with ragged red fibers. In five cases where sleep apnea was monitored, each one showed isolated or post-sigh central apnea, hiccup, apneusis-like breathing and obstructive apnea in various combinations. The remaining patient with Alpers/Leigh overlap syndrome showed an apneusis-like pattern of dyspnea. The sleep structure was examined in three patients.Two patients with brainstem lesions showed a decrease in the deep sleep stages and an absence of REM sleep. Medullary lesions were found in four patients by magnetic resonance imaging or at autopsy and involved predominantly the dorsal respiratory group (DRG) of medullary neurons. The role of DRG lesions in the pathophysiology of respiratory symptoms in Leigh syndrome is discussed.     

Diurnal sleep apnea in myotonic dystrophy]

We investigated diurnal sleep apnea in myotonic dystrophy with respiratory inductive plethysmography. Five of eight patients met criteria for sleep apnea syndrome and had central apnea mainly. In a case showing periodic breathing with apnea like Cheyne-Stokes type breathing, the duration of apnea and breath was even and the tidal volume went waxing and waning regularly. In the other four cases, central apneas were observed in sequence, but the duration of apnea and the tidal volume changed variously. Large breaths between apneas elevated arterial oxygen saturation rather than stable breaths without apnea. We suspected that hypoxemia, which exacerbated by involvement of respiratory muscles, supine position and sleep, initiated the hyperventilation between apneas. And then the saturation of oxygen raised by hyperventilation would cause central sleep apnea.     

Characteristics of obstructive and central sleep apnea in the elderly: an interim report

Home sleep recordings were done on 358 randomly selected elderly volunteers (mean age 72.4). When men and women were combined, 62 (17%) had predominantly obstructive sleep apnea, 21 (6%) had predominantly central sleep apnea, and 3 (1%) had mixed sleep apnea. Although the prevalence of sleep apnea in women does increase after menopause, sleep apnea was still significantly more common in older men (31%) than in older women (19%). There were no significant differences in age among groups with different types of apnea. There was a significant correlation of age with increasing apnea index within the obstructive sleep apnea group. Elderly volunteers with central sleep apnea had more midsleep awakenings. Elderly volunteers with obstructive sleep apnea had longer apneas. Unlike previous studies, we found many similarities and only modest differences in the presentations of central and obstructive sleep apnea.     

Sleep apnea: clinical investigations in humans

Sleep apnea syndrome (SAS), a common disorder, is characterized by repetitive episodes of cessation of breathing during sleep, resulting in hypoxemia and sleep disruption. The consequences of the abnormal breathing during sleep include daytime sleepiness, neurocognitive dysfunction, development of cardiovascular disorders, metabolic dysfunction, and impaired quality of life. There are two types of SAS: obstructive sleep apnea syndrome (OSAS) and central sleep apnea syndrome (CSAS). OSAS is a prevalent disorder in which there is snoring, repetitive apneic episodes, and daytime sleepiness. Anatomical conditions causing upper airway obstruction (obesity or craniofacial abnormalities such as retrognathia or micrognathia) can cause OSAS. CSAS, much less common than OSAS, is a disorder characterized by cessation of breathing which is caused by reduced respiratory drive from the central nervous system to the muscles of respiration. The latter condition is common in patients with heart failure and cerebral neurologic diseases. The diagnosis of SAS requires assessment of subjective symptoms and apneic episodes during sleep documented by polysomnography. Treatments of OSAS include continuous positive airway pressure (CPAP), oral appliances, and surgery; patients with CSAS are treated with oxygen, adaptive servo-ventilation, or CPAP. With assessment and treatment of the SAS, patients usually have resolution of their disabling symptoms, subsequently resulting in improved quality of life.     

Methadone and sleep apnea syndrome]

BACKGROUND: Sleep apnea syndrome occurs when, during sleep, breathing stops for 10 seconds or longer, with an index of 5 times or more an hour. It is clinically characterized by loud snoring at night, continuous or interrupted by pauses followed by loud breathing. Sleep is fitful, broken by arousals, and yields little rest. There is daytime excessive sleepiness with repeated involuntary falling asleep, often unknown by the subject. CLINICAL DESCRIPTION: In this article, we describe an observation of central sleep apnea syndrome in a female patient receiving an opiate replacement therapy. METHOD: An analysis of the before and after methadone withdrawal polysomnograhic tracing was done for this patient. RESULTS: This diagnosis etiology and physiopathology are critically approached. Clinicians should be careful in treating induced sleep disorders in such patients. Conclusion: Prescribing benzodiazepines during an opiate withdrawal of the methadone type is not recommended when central apnea occurs.     

Polysomnography in patients with intracranial tumors before and after operation

OBJECTIVE : To evaluate the breathing and sleep patterns in patients with brain tumors before and after operation, and assess their relation to the location and size of the tumor, as well as to the post-operative outcome. METHODS : Polysomnographic studies were performed in 11 patients with intracranial tumors (nine supra- and two infratentorial) before and after surgery. RESULTS : Pre-operatively, the mean apnea-hypopnea index (AHI) was 23.3. Six patients demonstrated signs of obstructive sleep apnea (SA) and one had mixed obstructive and central type SA. After operation, the mean AHI decreased to 8.1(P < 0.05). The duration of random eye movement sleep stage increased after tumor removal (P < 0.04). No relation was found between the characteristics of the tumor, nor the post-operative outcome and SA. CONCLUSIONS : Patients with brain tumors often suffer from SA and this can further worsen their symptoms related to increased intracranial pressure. Removal of the tumor results in a substantial decrease in sleep-related disturbances and may thus play a role in clinical recovery.     

Obstructive sleep apnea in association with posterior fossa neurologic disease

Sleep apnea in association with neurologic disease is uncommon, and its documentation with nocturnal polysomnography (PSG) is rare. Two patients with posterior fossa neurologic disease had obstructive and central sleep apnea on PSG. The first was a 40-year-old woman who experienced a respiratory arrest ten days after neurosurgical decompression of a cervical syrinx associated with syringobulbia. Nocturnal PSG demonstrated obstructive sleep apnea. Tracheostomy was performed and a second nocturnal PSG showed no sleep apnea. The second patient was a 76-year-old woman with daytime hypersomnolence, nocturnal choking spells, progressive spastic paraparesis, and left-sided cerebellar tremor. Neurologic evaluation led to the diagnosis of olivopontocerebellar degeneration. Nocturnal PSG showed multiple episodes of central and obstructive apnea. These cases support the hypothesis that central and obstructive sleep apnea can originate from a central mechanism.     

Respiratory arrest during sleep. Facts and hypothyses

The writers analyze 29 nyctohemeral recordings in 20 patients with sleep apneas. In addition to the standard polygraphy, use is made of pneumotachography and capnography. The results (central apnea with open or secondarily closed glottis; obstructive apnea with closed glottis or with expiratory valve phenomenon) raise the hypothesis of a central physiopathological mechanism common to the various types of apneas through a more or less dissociated inhibition of the activity of the respiratory, laryngeal, intercostal, and diaphragmatic muscles:--in central apnea: inhibition of the thoracoabdominal activity and maintenance of the tonicity of the laryngeal muscles, keeping the glottis open;--in obstructive apnea: persistence of the thoracic and/or abdominal activity with inhibition of the activity of the laryngeal muscles, leading to a passive obstruction due to the effect of inspiratory depression.