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Query: UMLS:C0037315 (sleep apnea)
 8,000 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sleep apnoea and hypopnoea have been reported in myotonic dystrophy, but it is unclear whether this is simply attributable to the respiratory muscle weakness which is common in this condition. We therefore investigated whether breathing and oxygenation during sleep were more abnormal in patients with myotonic dystrophy than in patients with non-myotonic muscle weakness. Seven subjects were studied in each of three groups: normal controls, myotonic dystrophy and non-myotonic weakness. Patients in the latter group were chosen to represent a similar range of severity of respiratory muscle weakness to those with myotonic dystrophy. Detailed polysomnography was performed; the severity of breathing disorders during sleep was quantified in terms of the frequencies of apnoea and hypopnoea and the degree of arterial desaturation. The myotonic patients showed more frequent apnoea and hypopnoea and more severe desaturation than the other two groups; the results in the non-myotonic patients were generally intermediate. The results suggest that abnormal breathing during sleep is common in myotonic dystrophy and is not due solely to the direct effects of respiratory muscle weakness. Somnolence, which is a well recognized symptom of myotonic dystrophy, was not clearly attributable to the sleep apnoea/hypopnoea syndrome nor to abnormal sleep architecture in the myotonic patients.
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PMID:Breathing during sleep in patients with myotonic dystrophy and non-myotonic respiratory muscle weakness. 167 61

To evaluate the morbidity associated with obstructve sleep apnea syndrome (OSAS), we undertook a seven-year follow-up study of 198 OSAS patients seen between 1972 and 1980. The patients had been submitted to tracheostomy (71 patients) or had received a weight-loss recommendation (127 patients). Despite a lower mean apnea index (AI) (43 vs 69) and a lower mean body mass index (BMI) (31 vs 34 kg/m2) at entry, excessive daytime sleepiness (EDS) and vascular morbidity were significantly higher in the conservatively treated group. The relative risk (odds ratio) of finding EDS in the conservatively treated group, after adjustment for BMI at seven-year follow-up, was 3.7 (95 percent confidence interval [CI] = 2.6-5.3). The relative risk of developing new vascular problems in the same population, estimated by Cox models, was 2.3 (95 percent CI = 1.5-3.6). The effect of tracheostomy, independent of age, BMI, and AI at entry, was highly significant. At entry, 56 percent of the population already had a vascular problem, particularly hypertension, thus emphasizing the need for earlier treatment of the sleep-related abnormal breathing.
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PMID:Daytime sleepiness and vascular morbidity at seven-year follow-up in obstructive sleep apnea patients. 229 60

We have investigated the ability of a statistical model developed from clinical data and questionnaire responses to predict disturbance of breathing during sleep. Data from 100 consecutive patients referred for sleep study for suspected sleep apnea were used to develop the model using logistic regression analysis. For each subject, the model predicted the probability of having an apnea-hypopnea index (AHI) greater than 15; this probability was compared with the AHI measured from sleep study. A probability cutoff point (= 0.15) was decided on that minimized the number of subjects with false-negative predictions. Four terms--apneas observed by bed partner, hypertension, body mass index, and age--were found to contribute significantly to the model with observed apneas being by far the most predictive term of the four (adjusted odds ratio 19.7). When the model was tested to estimate the probability of an AHI greater than 15 for 105 patients from a second group of consecutive patients referred for sleep study, the model correctly classified 33 of 36 patients with a measured AHI greater than 15 (sensitivity = 92%) and 35 of 69 patients with a measured AHI less than or equal to 15(specificity = 51%). This study shows that analysis of clinical features of patients presenting with suspected sleep apnea may reduce the need for sleep studies by about one-third yet still lead to the identification of the great majority of patients with abnormal breathing during sleep.
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PMID:Estimation of the probability of disturbed breathing during sleep before a sleep study. 236 60

Behavioral control of abnormal breathing in sleep was studied to determine if an intervention procedure could reduce apnea duration and also SaO2 (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 SaO2 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.
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PMID:Behavioral control of abnormal breathing in sleep. 325 50

We have observed patients who clinically have the obstructive sleep apnea syndrome but have no apneas, instead having recurrent nocturnal hypoventilation. There is disagreement about the definition and significance of such sleep-related hypopneas. We have thus analyzed breathing patterns, oxygenation and sleep records of 50 consecutive patients referred with the clinical features of the sleep apnea syndrome and found to have abnormal breathing during sleep to determine: (1) the best definition of hypopnea, and (2) how frequently patients have the clinical features of the sleep apnea syndrome without recurrent apneas. Hypopnea definitions based on decreases in thoracoabdominal movement yielded hypopnea frequencies that were significantly closer to desaturation and arousal frequencies than hypopnea definitions based on flow reduction. The best hypopnea definition was that of a 50% reduction in thoracoabdominal movement lasting for 10 s. This was validated in 33 normal subjects, all of whom had fewer than 11 hypopneas/h, and fewer than 14 apneas plus hypopneas/h of sleep. Thirty-two of the 50 patients had 10 or more apneas/h, the remaining 18 having 9 to 98 hypopneas/h such that all patients had more than 16 apneas plus hypopneas/h. Patients with recurrent hypopneas were clinically indistinguishable from and had a similar frequency of 4% desaturations (zero to 104/h) and arousals (7 to 98/h) to the patients with frequent apneas. This study confirms that hypopneas are clinically important and that the "sleep apnea syndrome" may occur in the absence of recurrent apneas.
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PMID:The sleep hypopnea syndrome. 335 98

In two adolescent and two adult patients with Kleine-Levin syndrome, polygraphic sleep recording performed during somnolent and non-somnolent periods revealed various forms of abnormal breathing patterns during sleep. These included periodic breathing and hypopnoeic episodes associated with brief arousals and, in one adult patient, a full blown sleep apnoea syndrome. It is suggested that abnormal breathing in sleep in this syndrome may result from central hypoexcitability.
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PMID:Further observations on sleep abnormalities in Kleine-Levin syndrome: abnormal breathing pattern during sleep. 616 60

Four morbidly obese men who had been found to have significant sleep-disordered breathing and oxygen desaturation were restudied after an average weight loss of 108 kg (range 53-155 kg). In all subjects, weight loss was accompanied by a significant reduction in the number of episodes per hour of sleep-disordered breathing events. In three of the four subjects, there was improvment in the severity of desaturation accompanying abnormal breathing. The two subjects with daytime somnolence and hypercapnia prior to weight loss showed the most dramatic improvement in desaturation. This suggests that obesity is a cause, rather than an effect, of the sleep apnea syndrome.
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PMID:The effect of weight loss on sleep-disordered breathing and oxygen desaturation in morbidly obese men. 710 55

BACKGROUND--The aetiology of the sleep apnoea/hypopnoea syndrome (SAHS) is unclear in many patients. Snoring, a prerequisite for SAHS, runs in families. A study was carried out to determine whether there is an increased frequency of irregular breathing during sleep in relatives of patients with SAHS. METHODS--A prospective study was performed of first degree relatives of 20 consecutive non-obese (BMI < 30 kg/m2) patients with SAHS. Questionnaires on SAHS symptoms were sent to all first order relatives and those living within 150 miles of Edinburgh were invited for overnight monitoring of their breathing, sleep, and oxygenation patterns in the sleep laboratory. RESULTS--Ten of the 40 relatives had more than 15 apnoeas + hypopnoeas/hour of sleep, and eight had more than five 4% desaturations/hour. These frequencies of irregular breathing and desaturation are significantly higher than in the British population. Cephalometric studies showed no skeletal abnormality but an increased uvular width was found in the affected relatives. CONCLUSIONS--There is an increased frequency of abnormal breathing during sleep in relatives of non-obese patients with SAHS.
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PMID:Is the sleep apnoea/hypopnoea syndrome inherited? 815 52

Progressive day-time sleepiness developed in a 73-year-old man for 3 years known to have kappa-light-chain myeloma, treated with radio- and chemotherapy. His powers of concentration and intellectual performance were diminished. Neither clinical nor biochemically was there any indication of abnormal water and electrolyte metabolism or hyperviscosity syndrome. The neurological examination was unremarkable. His wife's observation of nocturnal breathing pauses suggested sleep-related abnormal breathing. Polysomnography showed severe central sleep apnoea: an apnoea index of 60/h and blood oxygen saturations as low as 78%. On biphasic positive airway pressure (BIPAP) ventilation by nasal mask at night the apnoea index fell to 6/h and the symptoms improved. During a break in treatment the day-time sleepiness again increased and regressed once again with BIPAP ventilation. There is a 1-5% prevalence of sleep-related impaired breathing among adults. This condition should thus be considered in the differential diagnosis of characteristic day-time sleepiness.
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PMID:[Central sleep apnea syndrome as a cause of impaired wakefulness in multiple myeloma]. 828 78

Screening for sleep-disordered breathing is often done in an interview and with a questionnaire. This method is indirect and it appears to underestimate the prevalence of sleep apnea syndrome. Recently, several devices such as the Medilog and Vitalog portable monitoring systems were developed. However, these devices are difficult for patients to operate by themselves, because they include EEG monitoring or measurement of chest and abdominal movement. Therefore, we developed a portable monitoring system that is easier to operate. This system can be used to assess three variables: oronasal airflow, tracheal sound, and electrical activity of the heart. It stores the time of the onset of apnea, apnea duration, and R-R intervals with a built-in microcomputer. Apnea episodes, total apnea time, mean apnea time, and R-R interval are analyzed with a host computer. The sensitivity an specificity of this system are 92.5% and 87.5%, respectively, with an apnea index (AI) of less than 10 episodes/h. Using this device, we found that the prevalence of sleep apnea syndrome among Japanese industrial workers who had an AI of more than 10 episodes was 7.5%. Moreover, from 1984 to 1994 we used this device to monitor 1019 outpatients who complained of sleep disturbances such as snoring, abnormal breathing during sleep, and excessive daytime sleepiness, and found sleep apnea (AI > or = 10) in about 50% of these patients. This monitoring system is useful for screening of outpatients with sleep apnea and for epidemiological studies of sleep apnea. However, it may be necessary to include a non-invasive system for monitoring oxygen saturation in the portable sleep monitor, to detect hypoventilation during sleep.
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PMID:[Portable home monitoring system in screening for sleep-disordered breathing]. 875 82


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