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PubMed2005

The association of tongue scalloping with obstructive sleep apnea and related sleep pathology.

OBJECTIVE: The association between OSAS and patient history and physical exam findings is previously established; however, to our knowledge there are no studies that evaluate the role of tongue scalloping as a reliable clinical indicator for OSA, snoring, or the presence of other sleep pathology as evidenced by polysomnography. This study evaluates the hypothesis that such an association exists. SUBJECTS AND METHODS: Sixty-one otolaryngology clinic patients were evaluated by history and physical exam for the presence and degree of tongue scalloping, snoring, and other previously established clinical indicators for sleep-disordered breathing and obstructive apnea. Twenty-five of the 61 study patients were additionally evaluated by overnight polysomnography to provide conclusive diagnosis of sleep pathology. The degree of tongue scalloping was graded from 0 to 3 and its significance as a screening, diagnostic, and predictive factor for sleep pathology was then statistically determined. RESULTS: Twenty-seven patients (44%) had known or newly documented OSA and 47 (77%) had a history of snoring. Twenty-seven patients (44%) had some degree of tongue scalloping (1-3) and 74% of these patients were male. The presence of any degree of tongue scalloping (grade 1-3) in patients with known or newly documented OSA showed sensitivity, specificity, PPV, and NPV of 52%, 68%, 70%, and 50% respectively. The presence of tongue scalloping in patients with either known snoring history or newly documented snoring showed sensitivity, specificity, PPV, and NPV of 47%, 64%, 81%, and 26% respectively. Presence of tongue scalloping was 71% specific for abnormal sleep efficiency (<85%), 70% specific for abnormal AHI (>5), and 86% specific for nocturnal desaturation >4% below baseline. Presence of tongue scalloping also showed PPV of 67% for abnormal AHI, 89% for apnea or hypopnea, and 89% for nocturnal desaturation. Presence and severity of tongue scalloping showed positive correlation with increasing Mallampati and modified Mallampati airway classification. CONCLUSIONS: In high-risk patients we found tongue scalloping to be predictive of sleep pathology. Tongue scalloping was also associated with pathologic polysomnography data and abnormal Mallampati grades. We feel the finding of tongue scalloping is a useful clinical indicator of sleep pathology and that its presence should prompt the physician to inquire about snoring history.

Adult↗

PubMed2006

The effect of altitude descent on obstructive sleep apnea.

BACKGROUND: The present requirement for "at facility" polysomnograms requires many residents in mountain communities to descend in elevation for sleep testing, which may cause misleading results regarding the severity of obstructive sleep apnea (OSA). DESIGN: Eleven patients with previously undiagnosed sleep apnea living at an altitude > 2,400 m (7,900 feet) in Colorado underwent diagnostic sleep studies at their home elevation and at 1,370 m (4,500 feet), and 5 of the 11 patients were also studied at sea level. RESULTS: The mean (SE) apnea-hypopnea index (AHI) fell from 49.1 (10.5)/h to 37.0 (11.2)/h on descent to 1,370 m (p = 0.022). In the five patients who traveled to sea level, the AHI dropped from 53.8 (13.2)/h at home elevation to 47.1 (14.8)/h at 1,370 m, and to 33.1 (12.6)/h at sea level (p = 0.018). The reduction in AHI was predominantly a reduction in hypopneas and central apneas, with little change in the frequency of obstructive apneas. Duration of the obstructive apneas lengthened with descent. Of eight patients with an AHI < 50/h at their home elevation, two patients had their AHI fall to < 5/h at 1,370 m, and a third patient dropped to < 5/h at sea level, ie, below many physicians' threshold for providing therapy. Patients with the most severe OSA had the least improvement with descent. CONCLUSIONS: Because AHI decreases significantly with descent in altitude, polysomnography is most accurately done at the home elevation of the patient. Descent to a sleep laboratory at a lower elevation may yield false-negative results in patients with mild or moderate sleep apnea.

Adult↗

PubMed1991

Effect of weight loss on upper airway collapsibility in obstructive sleep apnea.

Previous investigators have demonstrated in patients with obstructive sleep apnea that weight reduction results in a decrease in apnea severity. Although the mechanism for this decrease is not clear, we hypothesize that decreases in upper airway collapsibility account for decreases in apnea severity with weight loss. To determine whether weight loss causes decreases in collapsibility, we measured the upper airway critical pressure (Pcrit) before and after a 17.4 +/- 3.4% (mean +/- SD) reduction in body mass index in 13 patients with obstructive sleep apnea. Thirteen weight-stable control subjects matched for age, body mass index, gender (all men), and non-REM disordered breathing rate (DBR) also were studied before and after usual care intervention. During non-REM sleep, maximal inspiratory airflow was measured by varying the level of nasal pressure and Pcrit was determined by the level of nasal pressure below which maximal inspiratory airflow ceased. In the weight loss group, a significant decrease in DBR from 83.3 +/- 31.0 to 32.5 +/- 35.9 episodes/h and in Pcrit from 3.1 +/- 4.2 to -2.4 +/- 4.4 cm H2O (p less than 0.00001) was demonstrated. Moreover, decreases in Pcrit were associated with nearly complete elimination of apnea in each patient whose Pcrit fell below -4 cm H2O. In contrast, no significant change in DBR and a minimal reduction in Pcrit from 5.2 +/- 2.3 to 4.2 +/- 1.8 cm H2O (p = 0.031) was observed in the "usual care" group. We conclude that (1) weight loss is associated with decreases in upper airway collapsibility in obstructive sleep apnea, and that (2) the resolution of sleep apnea depends on the absolute level to which Pcrit falls.

Adult↗

PubMed2004

Adenotonsillectomy for obstructive sleep apnea in obese children.

OBJECTIVE: To study changes in sleep behavior and quality of life in obese children after adenotonsillectomy for obstructive sleep apnea. Study design and setting Prospective study at the University of New Mexico Children's Hospital. METHODS: Children who met inclusion criteria and had a respiratory distress index (RDI) greater than 5 were enrolled in the study and underwent adenotonsillectomy. All children underwent preoperative and postoperative full-night polysomnography. Age- and gender-specific percentile BMI was recorded at the time of polysomnography. Caregivers were asked to complete an OSA-18 quality of life survey prior to polysomnography and a second survey within 6 months of surgery. Scores from preoperative and postoperative polysomnography and OSA-18 surveys were compared using the paired Student's t test. RESULTS: The study population included 30 children. Twenty-six children (86%) were male. The mean age of the children at the time of inclusion in the study was 9.3 years; range, 3.0 to 17.2. The mean preoperative BMI was 28.6 (range, 19.2 to 47.1) and the mean postoperative BMI was 27.9 (range, 17.8 to 27.9). A 2-tailed paired t test showed that this difference is not statistically significant (P = 0.06). The mean preoperative RDI was 30.0 and the mean postoperative RDI was 11.6 (P < 0.001). The preoperative mean total OSA-18 score was 78.2 and the postoperative mean total score was 39.8 (P < 0.001). CONCLUSION: Obese children with OSA who undergo adenotonsillectomy show a marked improvement in RDI and in quality of life with no change in BMI. However, in the majority of children, OSA does not resolve.

Adenoidectomy↗

PubMed1990

Surgical therapy of obstructive sleep apnea in children with severe mental insufficiency.

Obstructive sleep apnea is the underlying cause of a variety of pediatric maladies, including pulmonary hypertension and failure to thrive. In children, unlike adults, obstruction secondary to lymphoid hyperplasia is often encountered; adenotonsillectomy restores airway patency. Patients who fail this procedure, such as children with cerebral palsy and associated muscular hypotonia, may face tracheotomies. We report on 10 pediatric patients with severe mental insufficiency and obstructive sleep apnea in whom palatal hypotonicity and lack of adenotonsillar hypertrophy was identified. Uvulopalatopharyngoplasty was performed in conjunction with adenotonsillectomy to enlarge the diameter of the nasopharyngeal inlet with successful resolution of the obstructive symptoms in eight patients. The remaining two children required more surgery. This procedure is presented as a possible alternative to tracheotomy in selected patients.

Child↗

PubMed2002

Treating obstructive sleep apnea improves essential hypertension and quality of life.

About one half of patients who have essential hypertension have obstructive sleep apnea, and about one half of patients who have obstructive sleep apnea have essential hypertension. A growing body of evidence suggests that obstructive sleep apnea is a major contributing factor in the development of essential hypertension. Despite many patients with obstructive sleep apnea having clear symptoms of the disorder, an estimated 80 to 90 percent of cases are undiagnosed. When physicians routinely seek the diagnosis of obstructive sleep apnea by asking patients (especially those with hypertension) three basic sleep-related questions about snoring, excessive daytime sleepiness and reports of witnessed apneic events, the number of cases diagnosed and treated increases by about eightfold. Eliminating snoring and occurrences of apneic-hypopneic episodes will dramatically improve patients' quality of sleep and eliminate excessive daytime sleepiness, which has a detrimental effect on general functioning. Increased alertness will reduce the likelihood that patients will be involved in motor vehicle crashes. In most studies in which blood pressure was measured following treatment for obstructive sleep apnea, daytime and nighttime blood pressure levels were found to decrease significantly. This decrease in blood pressure may also reduce the likelihood of cardiovascular complications. The key to the diagnosis of obstructive sleep apnea is physician knowledge about the disorder. The dramatic improvement in quality of life that occurs when patients are successfully treated for obstructive sleep apnea makes detecting and treating this disorder imperative.

Diagnosis, Differential↗

PubMed1991

Severe obstructive sleep apnea and associated snoring documented during external tocography.

Severe obstructive sleep apnea, a disturbance of sleep resulting from intermittent periodic obstruction of the upper airway, was diagnosed after cardiotocography during which the external tocodynamometer disclosed a pattern initially thought to represent uterine activity. In spite of this obstructive sleep apnea with associated markedly low, hypoxic oxygen saturation levels and daytime somnolence of 10 to 12 hours from 32 weeks until delivery, subsequent fetal outcome was good.

Adult↗

PubMed2004

Treatment of snoring and obstructive sleep apnea with mandibular repositioning appliances.

Snoring and obstructive sleep apnea form part of a spectrum of sleep disordered breathing affecting a significant proportion of the general population and particularly the middle aged. The consequences can be severe and even life threatening for both the individual directly affected and those more remotely involved. Adverse sequelae can manifest themselves acutely or in the longer term as a result of obstructive breathing induced hypersomnolence, neurocognitive deficits and cardiovascular abnormalities. The combination of anatomical and neuromuscular risk factors in the pathogenesis of OSA has resulted in a varied approach to its management. One such treatment option is mandibular repositioning appliances (MRA), which mechanically stabilize the airway. Whilst the efficacy of this simple intervention has been rigorously proven quite recently in a significant proportion of patients with varying disease severity, individual patient selection in its application remains uncertain. Short-term side-effects are common but usually transient, whilst in the long-term minor permanent adverse developments on the dentition and occlusion have been reported. Considering both the medicolegal implications of snoring and OSA and the increasing popularity of MRA, it is recommended that skilled multidisciplinary respiratory and dental personnel form the primary care team.

Critical Pathways↗

PubMed2001

Higher prevalence of smoking in patients diagnosed as having obstructive sleep apnea.

Nightly nicotine withdrawal as well as other respiratory and pulmonary effects of smoking may result in sleep-disordered breathing, especially obstructive sleep apnea (OSA). We hypothesize that there is higher prevalence of smoking in patients with OSA. We also hypothesize that smoking is an independent risk factor for OSA. The aim of this study is to determine whether there is a higher prevalence of smoking in patients with OSA compared with patients who do not have OSA. To investigate this, we randomly selected a group of 108 patients who were diagnosed as having OSA, defined by an apnea-hypopnea index (AHI) of greater than 10 events per hour. We compared their smoking history with another randomly selected group of 106 patients without OSA, defined by an AHI of less than five events per hour. The prevalence of smoking in patients with OSA was found to be 35%, whereas it was only 18% in patients without OSA. Logistic regression analyses were performed to investigate the effects of smoking while adjusting for age, gender, body mass index (BMI), and number of alcoholic drinks per week. While holding fixed the BMI, gender, age, and number of alcoholic drinks per week, current smokers were found to be 2.5 times more likely to have OSA than former smokers and nonsmokers combined (odds ratio = 2.5, CI 1.3-4.7, p = 0.0049), and 2.8 times more likely to have OSA than former smokers alone (odds ratio = 2.8, CI = 1.4-5.4, p = 0.0028). Adjusted for BMI, gender, age, and number of alcoholic drinks per week, former smokers were not more likely than never smokers to have OSA (odds ratio = 1.2, CI = 0.55-2.7, p = 0.64). We conclude that cigarette smoke may be an independent risk factor for OSA in this referral population.

Body Mass Index↗

PubMed2003

Insulin resistance and obstructive sleep apnea: is increased sympathetic stimulation the link?

The science of sleep is in early stages of development, and the biochemical consequences of obstructive sleep apnea (OSA) are slowly being identified. Only recently have investigators begun to identify the commonalities and interaction between OSA and insulin resistance, the underlying pathology of type 2 diabetes. Obesity and increasing age play important parts in the natural history of both conditions, which frequently coexist. The purpose of this article is, first, to examine the extent and strength of studies that have investigated the association between OSA and increased insulin resistance or type 2 diabetes and, second, to propose a model that explains the association and cyclical interaction between OSA, obesity, and insulin resistance.

Age Distribution↗

PubMed2006

Comparison of the effects of depressive symptoms and apnea severity on fatigue in patients with obstructive sleep apnea: a replication study.

BACKGROUND: Links between fatigue and depressive symptoms in medically ill patients are well-documented; however, few studies controlled for illness severity. Obstructive sleep apnea (OSA) is a common, frequently devastating disease that often includes daytime sleepiness and fatigue. Fatigue is also a hallmark depressive symptom. We previously reported that depressive symptoms explained ten times the variance in fatigue in OSA patients as did OSA severity itself (respiratory disturbance index, oxyhemoglobin saturation). OSA severity explained 4.2% of variance in fatigue while depressive symptoms explained an additional 42.3%. Here, we report a replication of these findings in a new, independent sample. METHODS: 56 untreated OSA patients had their sleep monitored with polysomnography on the UCSD GCRC. Participants completed the Center for Epidemiologic Studies-Depression (CESD), Profile of Mood States (POMS) and Medical Outcomes Studies (MOS) surveys. Data were analyzed using hierarchical linear regression. RESULTS: OSA severity explained 13.4% (p=0.022) of variance in POMS fatigue while CESD scores explained an additional 24.5% (p<0.001). Results were robust to changes in the scales used to measure these constructs. LIMITATIONS: Cross-sectional design precludes determination of direction of causality. Assessment of depressive symptoms and fatigue was based on validated self-report measures. CONCLUSIONS: These results reaffirm that depressive symptoms are dramatically and independently associated with worse fatigue in OSA patients. While the independent contribution of OSA severity varied between studies, depressive symptoms were the strongest predictor of fatigue in both studies. Assessment and treatment of mood symptoms-not just treatment of OSA itself-might reduce fatigue in these patients.

Adult↗

PubMed1993

The role of nasal obstruction in obstructive sleep apnea syndrome.

In summary, there is much evidence in the literature that nasal obstruction causes obstructive sleep apnea, usually of mild to moderate degree, in many individuals. In addition, it is a contributory factor in individuals with severe obstructive sleep apnea. This appears to occur because of its contribution to upper airway resistance which directly or indirectly results in a reduction in intraluminal pressure during inspiration and collapse. Nasal obstruction via its influence on the so-called nasal-pulmonary reflex, may also result in alveolar hypoventilation. In patients who have symptoms consistent with obstructive sleep apnea syndrome and/or other disorders of excessive somnolence, a careful history eliciting findings of possible nasal obstruction as well as a thorough nasal examination is appropriate. If nasal obstruction is present, intervention should be considered as part of the routine therapy for obstructive sleep apnea syndrome.

Adult↗

PubMed1978

Obstructive sleep apnea in family members.

Two sons and their father had severe hypersomnolence and obstructive sleep apnea. A third son, although asymptomatic, was shown to have upper-airway obstruction during sleep. Electromyographic recordings of genioglossus activity in the two symptomatic sons revealed loss of tonic activity in early stages of sleep at times when sleep apnea occurred. The asymptomatic son showed loss of tonic activity during rapid-eye-movement sleep, the sleep period when upper-airway obstruction occurred. Two sudden deaths occurred in this family. A 30-year-old brother died at home while asleep, and a child of the asymptomatic brother died at the age of four months from presumed sudden-infant-death syndrome. Obstructive sleep apnea may have a familial basis; the tongue may be involved in the genesis of upper-airway obstruction during sleep.

Adult↗

PubMed2003

[Respiratory control during sleep and the development of nocturnal hypoxia in patients with obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: It is assumed that the reduced ventilatory control during sleep may be related to the nocturnal hypoxia in patients with obstructive sleep apnea hypopnea syndrome (OSAHS) and daytime CO(2) retention. METHODS: Oxygen desaturation index (ODI(4)), sleep time spent when SaO(2) was below 90% (SIT(90)), the lowest SaO(2) (LSaO(2)) and the mean SaO(2) (MSaO(2)) during sleep were measured in 24 OSAHS patients with daytime PaCO(2) > or = 45 mm Hg and 39 with PaCO(2) < 45 mm Hg. Hypoxic (DeltaP(0.1)/DeltaSaO(2)) and hypercapnic (DeltaP(0.1)/DeltaPaCO(2)) responsiveness were measured in 11 eucapnic and 4 hypercapnic patients during wakefulness, NREM and REM sleep stages. RESULTS: Compared with the eucapnic patients, all the hypercapnic patients had more severe hypoxia during sleep (P < 0.05). Although both groups had similar chemical responsiveness during wakefulness, the hypercapnic patients had lower DeltaP(0.1)/DeltaSaO(2) and DeltaP(0.1)/DeltaPaCO(2) during both REM and NREM sleep (P < 0.05). CONCLUSION: The depressed chemical responsiveness during sleep plays an important role in the development of nocturnal hypoxia in OSAHS patients with daytime CO(2) retention.

Carbon Dioxide↗

PubMed2004

Survey of children with obstructive sleep apnea syndrome in Hong Kong of China.

BACKGROUND: Obstructive sleep apnea affects up to 2.9% of children. This study was to determine demographic and clinical characteristics of a group of children with obstructive sleep apnea syndrome (OSAS) as defined by sleep polysomnography (PSG). METHODS: A prospective study was conducted in a public-funded general hospital in Hong Kong of China. Children confirmed to have OSAS by PSG were followed up between January 1997 and December 1998. Tonsillectomy and adenoidectomy (T&A) was offered to those with moderate to severe OSAS, and medication was offered to those with mild OSAS. All children were followed up regularly in the sleep clinic and sleep PSG was repeated for those with marked relapse in symptoms. RESULTS: Eighty-nine children (64 boys and 25 girls, mean age 7 years) were confirmed to have OSAS out of 352 children who underwent PSG during the study period. The most common symptoms of OSAS were snoring (100%) and sweating (81%) during sleep and nasal blockage (61%) and sleepiness (34%) during daytime. Severe OSAS occurred in 15 children. Moderate OSAS occurred in 33 children. Forty-one children had mild OSAS. Forty-nine children underwent T&A, 5 (boys, < 5 years) out of whom were found to have recurrent OSAS within 1 year. CONCLUSION: A male predominance has been found in a group of Hong Kong children with OSAS. Boys undergoing T&A at an early age (< 5 years) will be more likely to develop repeated OSAS.

Adenoidectomy↗

PubMed2002

Effects of treatment by laser-assisted uvuloplasty on sleep energy expenditure in obstructive sleep apnea patients.

The purpose of this study was to evaluate the effect of successful laser-assisted uvulopalatoplasty (LAUP) on sleep energy expenditure (EE) in obstructive sleep apnea syndrome (OSAS) patients. Fifteen healthy subjects (group I) and 25 patients with moderately severe or severe OSAS (group II) proven by overnight sleep study and who wanted LAUP were enrolled. During the night of the sleep studies, EE was measured with a metabolic cart (indirect calorimetry with canopy), including basal metabolic rate (BMR), mean sleep EE, lowest sleep EE, ratios of mean sleep EE/BMR, and lowest sleep EE/BMR. For the OSAS patients, a second sleep study with EE measurement was performed 3 months after LAUP. Based on this assessment of their sleep architecture, they were divided into 2 groups: responders (group IIa) and nonresponders (group IIb). The mean sleep EE, the ratio of mean sleep EE/BMR and lowest EE/BMR were significantly higher in group II than group I. After LAUP in group II, 6 patients were found to be responders (group IIa) and 19 patients were nonresponders (group IIb). Group IIa had decreased mean sleep EE, ratios of mean sleep EE/BMR, and lowest sleeping EE/BMR after LAUP than before LAUP compared with no significant changes in group IIb after LAUP. In conclusion, there is increased sleep EE in moderately severe OSAS patients when compared with normal controls. LAUP, when effective in reversing the sleep abnormalities, also normalizes the sleep EE. If it does not adequately treat the OSAS, however, the sleep EE remains abnormal.

Adult↗

PubMed2003

Relationship between surface tension of upper airway lining liquid and upper airway collapsibility during sleep in obstructive sleep apnea hypopnea syndrome.

Lowering surface tension (gamma) of upper airway lining liquid (UAL) reduces upper airway opening (anesthetized humans) and closing (anesthetized rabbits) pressures. We now hypothesize that in sleeping obstructive sleep apnea hypopnea syndrome (OSAHS) patients lowering gamma of UAL will enhance upper airway stability and decrease the severity of sleep-disordered breathing. Nine OSAHS patients [respiratory disturbance index (RDI): 49 +/- 8 (SE) events/h, diagnostic night] participated in a two-part, one-night, polysomnography study. In the first part, upper airway closing pressures (during non-rapid eye movement sleep, Pcrit) were measured and samples of UAL (awake) were obtained before and after 2.5 ml of surfactant (Exosurf, Glaxo Smith Kline) was instilled into the posterior pharynx. The gamma of UAL was determined with the use of the "pull-off" force technique. In the second part, subjects received a second application of 2.5 ml of surfactant and then slept the remainder of the night (205 +/- 30 min). Instillation of surfactant decreased the gamma of UAL from 60.9 +/- 3.1 mN/m (control) to 45.2 +/- 2.5 mN/m (surfactant group) (n = 9, P < 0.001). Pcrit decreased from 1.19 +/- 1.14 cmH2O (control) to -0.56 +/- 1.15 cmH2O (surfactant group) (n = 7, P < 0.02). Compared with the second half of diagnostic night, surfactant decreased RDI from 51 +/- 8 to 35 +/- 8 events/h (n = 9, P < 0.03). The fall in RDI (deltaRDI) correlated with the fall in gamma of UAL (deltagamma) (deltaRDI = 1.8 x deltagamma, r = 0.68, P = 0.04). Hypopneas decreased approximately 50% from 42 +/- 8 to 20 +/- 5 events/h (n = 9, P < 0.03, paired t-test). The gamma of UAL measured the next morning remained low at 49.5 +/- 2.7 mN/m (n = 9, P < 0.001, ANOVA, compared with control). In conclusion, instillation of surfactant reduced the gamma of UAL in OSAHS patients and decreased Pcrit and the occurrence of hypopneas. Therapeutic manipulation of gamma of UAL may be beneficial in reducing the severity of sleep-disordered breathing in OSAHS patients.

Adult↗

PubMed2004

[Short-term and long-term influences of nasal continuous positive airway pressure to sleep architecture of obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: To observe the short-term and long-term influences of nasal continuous positive airway pressure (nCPAP) to sleep architecture of obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: Thirty cases who were diagnosed as OSAHS patients by polysomnography (PSG) were enrolled in the study. They received the nCPAP treatment in hospital at first night and then at home. Seventeen healthy adults were enrolled as control group and experienced PSG monitoring and recording. The sleep architectures of control group and OSAHS group (before nCPAP, first night on the nCPAP and 6 months after continuous nCPAP treatment) were analysed. RESULTS: The sleep shift number, first stage sleep, second stage sleep, stage of slow wave sleep and stage of rapid eye movement (REM) sleep were 34.41 +/- 10.16, (5.95 +/- 3.89)%, (48.13 +/- 7.68)%, (18.30 +/- 4.71)%, and (26.83 +/- 6.65)%, respectively, in control group. These parameters in OSAHS group before nCPAP were 207.30 +/- 149.80, (21.42 +/- 10.17)%, (55.24 +/- 13.28)%, (15.38 +/- 19.57)%, and (10.15 +/- 7.82)%, respectively. At the first night of nCPAP treatment they were 55.77 +/- 25.04, (10.92 +/- 9.62)%, (50.19 +/- 13.34)%, (17.53 +/- 10.06)%, and (21.17 +/- 7.66)%, respectively. There were statistically significant differences between the PSG parameters before and after nCPAP treatment in OSAHS group (P < 0.05). After 6 months of nCPAP treatment, the stage of REM sleep was significantly shorter (P < 0.05), but the other parameters had no significant changes compared with those at the first night on nCPAP (P > 0.05). CONCLUSION: The sleep shift number and first stage sleep in OSAHS group were significantly increased, but the stage of REM sleep was significantly decreased than those in control group. The sleep architecture of OSAHS was significantly improved when the nCPAP treatment was given continuously.

Aged↗