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

The contractile properties of pharyngeal respiratory muscle are altered in sleep apnoea and in conditions associated with sleep apnoea, such as ageing. We hypothesized that the contractile properties of the pharyngeal musculature are also altered by obesity, another factor associated with sleep apnoea. Studies compared a pharyngeal muscle, the sternohyoid, with the diaphragm. These were chosen as representative muscles whose contraction has opposing effects on upper airway patency. Both muscles were removed from nine lean and nine obese male Zucker rats (a genetic model of obesity), and isometric contractile properties were studied in vitro at 37 degrees C. For the sternohyoid muscle, in obese compared to lean animals there were no significant differences in isometric contraction time (15.2 +/- 0.3 vs 14.2 +/- 0.6 ms, respectively), half-relaxation time (13.6 +/- 0.5 vs 12.6 +/- 0.9 ms, respectively), twitch-to-tetanic tension ratio (0.22 +/- 0.02 vs 0.24 +/- 0.02, respectively), force-frequency relationship, fatigue resistance (2 min fatigue index 0.20 +/- 0.03 vs 0.18 +/- 0.02, respectively), or maximal degree of force potentiation during repetitive stimulation (52 +/- 11 vs 74 +/- 20% increase, respectively). For the diaphragm, the only significant effect of obesity was a lowering of the twitch-to-tetanic tension ratio (0.25 +/- 0.01 vs 0.29 +/- 0.02, respectively). In obese, as in lean animals, the sternohyoid had faster isometric twitch kinetics, a larger degree of force potentiation, and lower resistance to fatigue, than the diaphragm. In lean, but not obese, animals the sternohyoid twitch-to-tetanic tension ratio was lower than and the force frequency relationship was located to the right of that of the diaphragm. In this study, genetic obesity in rats was not associated with any significant alterations in the contractile properties of the pharyngeal muscle, and only small changes in the relationship between the contractile properties of the sternohyoid and diaphragm muscle.
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PMID:Effects of genetic obesity on rat upper airway muscle and diaphragm contractile properties. 890 80

To measure vigilance disorders in healthy normals or in patients (narcolepsy, sleep apnea syndrome) is difficult, time-consuming and hardly objective with present methods. Recording and analysis of spontaneous pupillary behaviour in darkness by infrared video pupillography is an objective and time-saving method to measure daytime sleepiness. However, certain external conditions must be satisfied (avoid light, noise, stress) to get reliable results. Spontaneous pupillary oscillations are recorded in darkness over 10 min and data are analyzed by fast Fourier transformation, with additional calculation of the mean pupillary diameter for each time segment (approx. 1 min). While in the alert normal, pupil remains dilated during the measurement in darkness and oscillates with an amplitude below 0.3 mm and a frequency about 1 Hz, there are characteristic changes in fatigue: (1) low-frequency components dominate the spontaneous pupillary oscillations, with an amplitude reaching several millimeters, and (2) pupil diameter decreases with time. Infrared video pupillography could play a role as a screening method and therapy control for hypersonic patients (most frequent: sleep apnea syndrome) with excessive daytime sleepiness. An objective, time-saving method like infrared video pupillography would be useful in sleep medicine and psychiatry when testing the level of vigilance, and in psychology or industrial medicine as well, providing informations about acute vigilance problems in healthy normals.
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PMID:[Pupillography for objective vigilance assessment. Methodological problems and possible solutions]. 896 45

The aim of this study was to determine whether diaphragmatic fatigue develops over the course of the night in patients with obstructive sleep apnoea (OSA). Patients with severe OSA underwent overnight polysomnography with the addition of gastric and oesophageal catheters for measurement of transdiaphragmatic pressure (Pdi) (n = 7) and a gastro-oesophageal electrode for determination of diaphragmatic electromyogram (EMGdi) (n = 5). Analyses of Pdi and EMGdi were performed to detect fatigue during the large inspiratory efforts at the end of apnoeas in Stage 2 sleep at the beginning and end of the night. Measurements included Pdi values, shape analysis of the Pdi waveform, the relaxation rate (tau R) of Pdi, EMGdi and its relationship to Pdi, and the centroid frequency (fc) of EMGdi. End of apnoeic Pdi and EMGdi increased from the beginning to end of the night (e.g. 19 +/- 14% increase in Pdi; p < 0.05). The rate of increase in Pdi and EMGdi during apnoeas did not change. The Pdi versus EMGdi relationship was linear, and remained unchanged over the course of the night. There was no significant change in the shape of the Pdi waveform, and there were no changes in tau R from the beginning to the end of the night (0.13 +/- 0.01 s for both periods). There was also no shift in the fc of the EMGdi power spectrum (94 +/- 5 vs 93 +/- 6 Hz; NS), and no change in the relationship of fc to Pdi or EMGdi from the beginning to the end of the night. These findings do not support the development of diaphragmatic fatigue over the course of the night in obstructive sleep apnoea.
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PMID:Lack of evidence for diaphragmatic fatigue over the course of the night in obstructive sleep apnoea. 903 5

To assess the relationship between chronic bronchitis and obstructive sleep apnoea, a postal survey was performed. A postal questionnaire was sent to 523 subjects identified as having chronic bronchitis or long-standing cough and sputum production in the Obstructive Lung Disease in Northern Sweden Study I (OLIN I). In 1986-88, all 6610 adults born in 1919-20, 1934-35 and 1949-50 living in representative areas in Northern Sweden were screened for airway diseases according to different methods. A random sample of healthy adults identified in the screening were chosen as references (n = 625). Subjects were asked about a variety of airway symptoms, smoking habits and symptoms related to obstructive sleep apnoea syndrome (OSAS). In the bronchitic group, 20% did not report bronchitic symptoms in the present study, and 26% of the formerly healthy reference group reported at least one bronchitic symptom in the present study. Snoring, apnoea and liability to 'nod off' during activity were much more common in the bronchitic group in both men and women, and most common in men, as expected. Snoring was reported by 29% of the men in the bronchitic group and by 14% in the reference group. In women, the corresponding figures were 14 and 8%, respectively, and for apnoea, the figures were 25 vs. 11% in men and 6 vs. 4% in women. The prevalence of OSAS symptoms was similar in subjects with attacks of breathlessness, long-standing cough, sputum production and recurrent wheezing. Bronchitic symptoms may influence quality of sleep and contribute to daytime tiredness, but this does not fully explain the high prevalence of snoring and apnoea reported by subjects in this cohort. This study indicates a positive correlation between chronic bronchitis and OSAS, but sleep studies are required to confirm this.
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PMID:Symptoms related to snoring and sleep apnoea in subjects with chronic bronchitis: report from the Obstructive Lung Disease in Northern Sweden Study. 906 11

The prevalence of sleep apnea-hypopnea syndrome (SAHS) was investigated in a selected group of veterans of the Persian Gulf War at Brooke Army Medical Center. One hundred ninety-two self-referred patients participated in the full evaluation of the Comprehensive Clinical Evaluation Program (CCEP) for veterans of the Persian Gulf War. After completing an initial survey, an interview and examination were performed by staff internists. Forty-six participants with histories suggestive of a sleep disorder were referred for further evaluation. Those patients suspected of SAHS then completed a sleep disorders questionnaire and underwent standard nocturnal polysomnography (PSG). SAHS was defined as a respiratory disturbance index > or = 15 in a symptomatic patient. Fifteen of 46 patients undergoing PSG at this institution met criteria for SAHS. The majority of these patients had symptoms of fatigue and memory loss. Overall, 16 of the 192 patients (8.3%) in the CCEP of our institution were diagnosed with SAHS. SAHS may play a significant role in the symptom complex presented by many veterans of the Persian Gulf War.
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PMID:Sleep apnea-hypopnea syndrome in a sample of veterans of the Persian Gulf War. 911 May 48

Sleep-related breathing disorders (SRBD) include several disorders gradually developing from simple and loud snoring through upper airway resistance syndrome and sleep apnoea up to the Pickwickian syndrome. They are manifestant as a respiratory distress and apnoeic episodes, desaturation of oxygen in the blood and interruption of sleep. These symptoms are demonstrated in a case of a patient with the Pickwickian syndrome. SRBD may result in severe secondary life-threatening cardiovascular complications (nocturnal arrhythmias, sudden cardiac death, stroke and pulmonary oedema). They may contribute also to the development of important disorders of public health such as hypertension, obesity, and traffic accidents resulting from hypersomnolence and fatigue. (Tab. 1, Fig. 3, Ref. 46.)
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PMID:[Sleep-related breathing disorders--an interdisciplinary topic in undergraduate and postgraduate medical education]. 926 12

Many clients have trouble battling afternoon fatigue, falling asleep, staying asleep, or having a restful night's sleep. Approximately 33% of the adult U.S. population--about 65 million people--suffer from sleep disorders. One of two people have experienced insomnia. At least 10 million people have sleep apnea, hundreds of thousands have experienced narcolepsy, and approximately 12 million suffer from restless legs syndrome or periodic limb movements during sleep. However, most people with sleep disorders remain undiagnosed and untreated.
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PMID:Sleep disorders. 964 67

With unfortunate high frequency, clinicians consider allergic rhinitis to be more of a nuisance than an illness. When in fact, allergic rhinitis is not only a very common disease process, affecting up to a cumulative frequency of 42% of the U.S. population by age 40, but can lead to significant short-term and long-term medical complications. Poorly controlled symptoms of allergic rhinitis may contribute to sleep loss, secondary daytime fatigue, learning impairment, decreased overall cognitive functioning, decreased long-term productivity and decreased quality of life. Additionally, poorly controlled allergic rhinitis may also contribute to the development of other related disease processes including acute and chronic sinusitis, recurrence of nasal polyps, otitis media/otitis media with effusion, hearing impairment, abnormal craniofacial development, sleep apnea and related complications, aggravation of underlying asthma, and increased propensity to develop asthma. Treatment of allergic rhinitis with sedating antihistamine therapy may result in negative neuropsychiatric effects that contribute to some of these complications. Sedating antihistamines may also be dangerous to use in certain other settings such as driving or operating potentially dangerous machinery. In contrast nonsedating antihistamines have been demonstrated to result in improved performance in allergic rhinitis.
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PMID:Complications of allergic rhinitis. 1047 18

This study compared sleep architecture in women and men with sleep apnoea syndrome. Women (n = 126) had longer sleep latencies, greater amounts of slow wave sleep, and fewer awakenings during the night than men (n = 181), despite no differences in age, RDI (Respiratory Disturbance Index) or oxygen saturation. In a subgroup of men and women treated with nasal CPAP, gender differences generally persisted. There was no difference in the complaint of daytime sleepiness between the groups, but the women reported more fatigue during the day than the men, as well as complaining about more sleep disturbance at night. We interpret these differences in terms of known gender differences in sleep architecture and sleep complaints.
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PMID:Gender differences in sleep architecture in sleep apnoea syndrome. 1060 26

Pharyngeal and diaphragm muscles contract and relax in synergy, which is why it was decided to compare their mechanical performance throughout the overall load continuum. The effects of fatigue were also studied. The isotonic mechanics of rat sternohyoid (SH; n=10) and diaphragm (D; n=10) were investigated in vitro. Force and length were measured in muscles contracting from zero load up to isometry. Maximum isometric tension (Pmax), peak mechanical work (Wmax), maximum unloaded shortening velocity (vzL) and mechanical efficiency (eff(max)) were recorded. Data were obtained both at baseline and after fatigue. SH muscles had a lower Pmax (96.0+/-13.7 versus 119.5+/-22.7 mN x mm(-2); p<0.05), a lower Wmax (5.5+/-1.2 versus 8.0+/-2.1 mJ x g(-1); p<0.01), a lower eff(max) (56.0+/-6.9 versus 62.6+/-5.8%; p<0.05) and a higher vzL (4.8+/-0.4 versus 3.4+/-0.4 initial length (L0) x s(-1); p<0.001) than D muscles. Wmax occurred at a higher relative load in SH (40% Pmax) than in D (30% Pmax). Fatigue did not modify eff(max) in SH muscles, whereas it significantly improved eff(max) in D muscles. These findings suggest that under control conditions, economy of force generation was less efficient in sternohyoid than in diaphragm muscles. Fatigue in sternohyoid muscles induced unfavourable mechanical behaviour. This may partly explain pharyngeal dilator muscle failure in the presence of increased loads. Whether these findings are relevant to human sleep apnoea syndrome has yet to be determined.
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PMID:Isotonic mechanics of a pharyngeal dilator muscle and diaphragm in the rat before and after fatigue. 1070 97


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