Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0037315 (sleep apnea)
 8,000 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

25 patients with idiopathic erythrocytosis (absolute increase in red cell mass without conventional criteria of primary polycythaemia or known underlying cause) have been further studied for evidence of primary or secondary polycythaemia. Additional non-conventional criteria used were: platelet distribution width, platelet nucleotide ratio, serum erythropoietin, clinical evidence of ischaemic vascular disease and erythroid culture variables in serum-free system. All had been used in an earlier study in score form to assist in the diagnosis of primary polycythaemia. These patients were also newly assessed for the presence of hypoxia (supine oximeter values, history suggestive of sleep apnoea), for renal lesions and for splenic enlargement (impalpable) by ultrasound or computerized tomography. 7 patients had erythroid culture scores suggesting primary polycythaemia but the addition of non-culture criteria did not result in any scores more strongly predictive of primary polycythaemia. Supine oximeter values < 92% suggested hypoxaemia as the mechanism of polycythaemia in 3 patients in whom it had not previously been suspected. Some splenic enlargement (impalpable) was demonstrated in 6 patients, only 1 of whom had erythroid culture scores suggesting primary polycythaemia. 12 patients had confirmed, raised erythropoietin levels. We conclude that idiopathic erythrocytosis refers to a heterogenous group of patients. Features of primary or secondary polycythaemia may be demonstrated in some of them by additional new study techniques. The raised erythropoietin values found in half the patients were unexpected.
Eur J Haematol 1994 Sep
PMID:Idiopathic erythrocytosis--additional new study techniques suggest a heterogenous group. 792 59

Sleep apnea syndrome (SAS) consists of nocturnal snoring interrupted by obstructive apnea and of diurnal symptoms like hypersomnolence as a consequence of sleep fragmentation. Cardiovascular morbidity and mortality associated with this syndrome justify early detection and appropriate treatment. Polysomnography is still a frequently used method for early detection; however, several disadvantages like duration, discomfort and expense led to a search for alternatives. Since the beginning of the eighties, oximetry allows recording of nocturnal oxygen saturation of hemoglobin even at home. Nocturnal oximetry reveals O2-desaturation associated with apnea and thus permits often to diagnose or exclude SAS. Diagnosis of SAS is made when at least 20 desaturations per hour with an amplitude of at least 4% are recorded. On the other hand, normal nocturnal oximetry nearly excludes SAS. In those cases where nocturnal oximetry is not diagnostic, polysomnography remains the method of choice. Departing from published work, a model for SAS detection, based mainly on nocturnal oximetry, is proposed.
Schweiz Rundsch Med Prax 1994 Sep 13
PMID:[Screening for sleep apnea syndrome]. 793 64

Twenty patients with sleep apnea syndrome were examined polysomnographically with and without an Esmarch sleep apnea appliance. The relationship between the therapeutic effect of the device and dentofacial morphologic characteristics of the patients were analyzed with the use of diagnostic casts and cephalometric radiographs. The apnea index or number of apneic episodes per hour decreased significantly (p < 0.0001) after insertion of the appliance. The diagnostic casts and cephalometric analyses revealed that the device was most effective for patients who exhibit a tendency toward micrognathia (p < 0.03) and a short soft palate (p < 0.01). The Esmarch appliance is indicated for the treatment or diagnosis of sleep apnea syndrome.
J Prosthet Dent 1994 Sep
PMID:Prosthetic therapy for sleep apnea syndrome. 796 3

The purpose of this study was to compare the effects of a modified Herbst appliance (mHA) and a muscle relaxation appliance (MR) on nocturnal breathing and body movement activity in patients with obstructive sleep apnoea syndrome (OSAS). To increase the airway space posterior to the tongue base without severely affecting the craniomandibular joint, the mHA was adjusted to anchor the mandible at 50% of maximum protrusion. MR producing an occlusal coverage but no protrusion served as a control appliance. All-night static charge-sensitive bed (SCSB) and finger oximeter recordings were done to six male patients in three conditions: first without dental device and then with mHA and with MR, in a random order, after a 2 month period of habituation. The oxyhaemoglobin desaturation events were 44.7 h-1 of recording observed during the control night, 29.6 h-1 with mHA (P = 0.087). The frequency of body movements decreased from 34.9 to 20.4 h-1 (P = 0.0079), respectively. MR had no significant effects either on the frequency of the desaturation events or the frequency of body movements, but the increased respiratory resistance breathing, indicating presence of partial upper airway obstruction, was reduced from 14.3 to 6.9% of the time in bed (P = 0.022). We conclude that 50% protrusion chosen for these experiments, produced with a mHA, brought about some alleviation of upper airway obstruction in our preselected patients, but did not lead to sufficient control of apnoea. The reduction of partial upper airway obstruction induced with a MR warrants further studies in a larger patient population.
J Oral Rehabil 1994 Sep
PMID:Mandibular advancement with dental appliances in obstructive sleep apnoea. 799 43

It has been shown that nasal continuous positive airway pressure (nasal CPAP) significantly reduces nocturnal reflux both in patients with sleep apnea and in patients without sleep apnea but consistent abnormal nocturnal reflux. The mechanism by which CPAP is thought to reduce reflux includes the elevation of the resting lower esophageal sphincter (LES) pressure. In this study, we tested the effect of nasal CPAP in two groups of patients with aperistaltic esophagus but with different resting LES pressure. Seven patients with scleroderma esophagus and six patients treated for achalasia were tested over a 48-h period. On the first night, the patients were untreated; on the second night, both groups received applied nasal CPAP at 8 cm H2O pressure. The percentage of time the pH < 4.0, the number of reflux events > 5 min, and the length of the longest reflux event were all significantly reduced in the patients with achalasia (p < 0.03), but not in the scleroderma group (p > 0.20). These results suggest that a residual resting LES pressure greater than that demonstrated by patients with scleroderma (> 10 mm Hg) may be necessary for nasal CPAP to affect nocturnal reflux.
Chest 1994 Sep
PMID:The effect of nasal CPAP on nocturnal reflux in patients with aperistaltic esophagus. 808 51

We measured electromyograms (EMGs) of genioglossus muscle (GG) and inspiratory intercostal muscle (IIM) in both rapid eye movement (REM) sleep and non-REM sleep of 12 patients with obstructive sleep apnea (OSA) to examine the influence of different sleep stages on upper airway muscle activity during sleep apnea. Quantifications of both muscle activities were assessed by their individual peak amplitude of integrated inspiratory EMG. Genioglossus and IIM activities showed a qualitatively similar cyclic change with an alteration of apneic and ventilatory phases during both non-REM and REM sleep. Both muscle activities increased gradually in the late apneic phase and reached each peak at the opening of the upper airway and, subsequently, decreased gradually. There were no significant differences in both muscles activities in either the ventilatory or early apneic phase between non-REM sleep and REM sleep. On the other hand, GG and IIM activities in the late apneic phase during REM sleep were significantly lower than those during non-REM sleep. The relative activity of GG to IIM in the late apneic phase was significantly lower during REM sleep than that during non-REM sleep. These results indicate that upper airway and intercostal muscle activation in the later apneic phase during REM sleep were inhibited compared with those during non-REM sleep and that this inhibition was observed predominantly in upper airway muscles.
Chest 1994 Sep
PMID:Upper airway muscle activity during REM and non-REM sleep of patients with obstructive apnea. 808 57

This study was designed to determine the impact of central sleep apnea with or without Cheyne-Stokes respiration (CSR) on morbidity and mortality. Central sleep apnea was found in 77 male general medical ward in-patients. Cheyne-Stokes respiration was found in 49 of the 77 men; in 15 men, CSR was severe, ie, > or = 25 percent of the night spent in CSR, in 34 men CSR was mild (1 to 25 percent CSR). Twenty-eight men had central sleep apnea but no CSR. An additional 31 patients had no sleep apnea and no CSR. The patients with severe CSR had more central apneas, more, but shorter desaturations, more awakenings and more wake time during the night, but spent more time in bed than those with no CSR or no apnea. Radiographic evidence was consistent with an association of CSR and heart failure. In addition, patients with severe CSR were at almost twice the risk of dying compared with those with no apnea and had a shorter survival time. Nevertheless, we could not confirm that CSR was an independent predictor of elevated mortality risk, implying that some other factors specific to severe CSR predispose these patients to shorter survival time.
Chest 1994 Sep
PMID:Comparison of patients with central sleep apnea. With and without Cheyne-Stokes respiration. 808 59

This study addresses the hypothesis that patients with obstructive sleep apnea, who exhibit recurrent episodes of oxygen desaturation at night, have higher hematocrit levels than nonapneic control subjects. We prospectively studied 624 patients referred to the sleep disorders center at St. Michael's Hospital because of suspicion of sleep apnea. All patients had nocturnal polysomnography and measurements of hematocrit level, hemoglobin value, WBC count, and platelet count. Smoking history and awake oxygen saturation (SaO2) was recorded in all of them. Nocturnal oxygenation was assessed using three indices: lowest nocturnal SaO2 (LoSaO2), mean nocturnal SaO2 (MnSaO2) and percent of total sleep time spent at SaO2 lower than 85 percent (TST85%). Patients with TST85% in the lowest quartile (TST85% = 0) had minimally lower hematocrit levels than patients with TST85% in the highest quartile (8 < or = TST85% < or = 90): 0.41 +/- 0.03 vs 0.40 +/- 0.02 in female subjects and 0.45 +/- 0.05 vs 0.43 +/- 0.05 in male subjects, respectively (p < 0.05). Multiple linear regression analysis revealed that MnSaO2, age, and pack-years of smoking were significant predictors of hematocrit level, but they accounted for only 9 percent of the variability in hematocrit level (multiple R2 = 0.087; p < 0.05). We conclude that intermittent nocturnal hypoxemia during episodes of apnea does not lead to clinical polycythemia, but is associated with minor elevations in hematocrit value. These small elevations are unlikely to be useful as markers of hypoxic stress associated with sleep apnea.
Chest 1994 Sep
PMID:Hematocrit levels in sleep apnea. 808 60

The as yet unanswered question, whether patients with sleep apnoea and apnoea-associated bradyarrhythmias have a higher morbidity and mortality rate, was retrospectively investigated in 132 men with sleep apnoea (apnoea index > 10/h). Sleep-associated bradycardic arrhythmias were recorded in 71 (mean age 50.1 years; group 1). For comparison served 61 men with sleep apnoea but no bradyarrhythmias (mean age 51.4 years; group 2), matched for age and weight. There was no significant difference between the two groups as to diagnosis and initial findings on ergometry, lung function tests and blood gas analysis. The apnoea index of 48.1 +/- 23.9/h in group 1 was significantly higher than that of 31.9 +/- 20.1/h in group 2 (P < 0.001). During a follow-up period of a mean of 41.1 (19-66) months, two patients in group 1 died (of myocardial infarction), while one died (of bronchial carcinoma) in group 2 (follow-up period of 29.6 [18-54] months). The two deaths in group 1 were in a subgroup of 16 patients who had declined treatment or had used it irregularly. There was no death among those who had been treated (n = 54), by nasal continuous positive airway pressure, operation or pacemaker implantation. However, no causal relationship could be established from these data between increased mortality rate and apnoea-associated arrhythmias.
Dtsch Med Wochenschr 1994 Sep 09
PMID:[Morbidity and mortality in sleep apnea and nocturnal bradyarrhythmia]. 808 84

A 47 year old man with a long history of chronic loud snoring and daytime sleepiness presented with hypercapnic respiratory failure and right ventricular failure. The diagnosis of obstructive sleep apnoea (OSA) leading to the 'obesity-hypoventilation syndrome', was supported by the findings of an overnight cardio-respiratory monitoring during sleep. His symptoms and arterial blood gases improved following treatment with nocturnal nasal continuous positive airway pressure (CPAP).
Med J Malaysia 1993 Sep
PMID:Cor pulmonale due to obstructive sleep apnoea. 818 51


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