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PubMed2006

The risk profile for obstructive sleep apnea does not affect the recurrence of atrial fibrillation.

BACKGROUND: Obstructive sleep apnea (OSA) has been linked to increased prevalence and recurrence of atrial fibrillation (AF). We hypothesized that OSA may aggravate AF in patients with pacemakers implanted for sinus bradycardia who had documented paroxysmal AF. METHODS: Seventy-two patients (36 M, aged 77 +/- 6 years) completed the study. All patients received a dual-chamber pacemaker equipped with diagnostic and preventive functions for AF. OSA was diagnosed with the Berlin Questionnaire, which is validated to identify patients with OSA. Four-month continuous pacemaker recordings were collected for all patients. RESULTS: OSA was diagnosed in 28% of patients. Patients at high risk for OSA (HR group) and patients at low risk for OSA (LR group) were equivalent for gender, age, and body mass index. The rate of hypertension was higher in HR than in LR group (90% vs 44%, P < 0.01). The prevalence of paroxysmal AF during the study period was similar in HR and LR group (53% vs 44%, P = NS). Overall number of AF episodes per month was not significantly different between HR and LR group (7 +/- 13 vs 36 +/- 122, P = NS). Similarly, AF burden (AF%) was not significantly different between HR and LR group (0.3 +/- 0.6 vs 2.0 +/- 4.8, P = NS). Circadian distribution of AF episodes was similar in both groups. CONCLUSION: Long-term pacemaker recording of AF recurrence, AF burden, and its circadian distribution is similar in patients with paroxysmal AF at high risk for OSA and those at low risk for OSA.

Aged↗

PubMed2006

Epilepsy and obstructive sleep apnea.

A few publications documented the coexistence of epilepsy and obstructive sleep apnea (OSA). The extent, nature, and clinical relevance of this association remain poorly understood. We retrospectively reviewed the database of our sleep center to identify patients with both sleep apnea and epilepsy. Characteristics of epilepsy, sleep history, presence of excessive daytime sleepiness [Epworth Sleepiness Scale (ESS)] and polysomnographic data were assessed. The effect of continuous positive airway pressure (CPAP) on seizure reduction was prospectively analyzed after a median interval of 26 months (range: 2-116 months) from the diagnosis of OSA. OSA was found in 29 epilepsy patients (25 men and 4 women) with a median age of 56 years (range: 37-79). The median apnea hypopnea index was 33 (range: 10-85), the oxygen desaturation index was 12 (range 0-92), and 52% of the patients had an ESS score >10. In 27 patients, epilepsy appeared 1 month to 44 years prior to the diagnosis of OSA. In 21 patients, the appearance of OSA symptoms coincided with a clear increase in seizure frequency or the first appearance of a status epilepticus. Treatment with CPAP was continued with good compliance in 12 patients and led to a significant reduction of both ESS scores and seizure frequency in 4 patients. Our data suggest the importance of considering diagnosis and treatment of OSA in epilepsy patients with poor seizure control and/or reappearance of seizures after a seizure-free interval.

Adult↗

PubMed2006

Aortic stiffness, flow-mediated dilatation and carotid intima-media thickness in obstructive sleep apnea: non-invasive indicators of atherosclerosis.

BACKGROUND AND OBJECTIVE: Obstructive sleep apnea (OSA) has a critical association with cardiovascular mortality and morbidity. Carotid intima-media thickness (IMT), flow-mediated dilatation (FMD) and aortic stiffness are early signs of atherosclerosis. The presence of subclinical atherosclerosis was assessed in OSA patients using these parameters. METHODS: 40 patients with OSA showing an apnea-hypopnea index (AHI) > or =5 (mean age 51.3 +/- 9 years, 32 males) and 24 controls (AHI < 5, mean age 51.9 +/- 5.2 years, 19 males) were enrolled in the study. In all subjects, polysomnographic examination and recordings were performed during sleep. IMT of the carotid artery, endothelium-dependent/-independent vasodilation of the brachial artery and aortic elastic parameters were investigated using high-resolution Doppler echocardiography. RESULTS: The demographic data of the patients with OSA and controls were not significantly different. Subjects with OSA demonstrated higher values of aortic stiffness (7.1 +/- 1.88 vs. 6.42 +/- 1.56, respectively) and IMT (0.85 +/- 0.13 vs. 0.63 +/- 0.11 mm, p = 0.0001, respectively) but lower distensibility (9.47 +/- 1.33 vs. 11.8 +/- 3.36 cm(2)/dyn/10(6)) and FMD (4.57 +/- 1.3 vs. 6.34 +/- 0.83%, p = 0.0001, respectively) than the controls. The respiratory disturbance index correlated positively with aortic stiffness and IMT and negatively with distensibility and FMD. CONCLUSION: We observed blunted endothelium-dependent dilatation, increased carotid IMT and aortic stiffness in patients with OSA compared with matched control subjects. This is evident in the absence of other diseases, suggesting that OSA is an independent cause of atherosclerosis. These simple and non-invasive methods help to detect subclinical atherosclerosis in OSA.

Aorta, Thoracic↗

PubMed1994

Four-year follow-up after uvulopalatopharyngoplasty in 50 unselected patients with obstructive sleep apnea syndrome.

Fifty unselected consecutive patients with obstructive sleep apnea syndrome (OSAS) diagnosed by nocturnal recordings of respiration movements by a static charge sensitive bed (SCSB) and oximetry, alone or combined with polysomnography, were studied. Renewed SCSB-oximetry recordings evaluated treatment. Six months after surgery, 30 of 50 were classified as responders. Twenty-one months after surgery, 19 of 49 were responders. Patients who relapsed showed a significant increase in mean body mass index (BMI). Four years after surgery, 24 of 48 patients were responders. Preoperative BMI was significantly lower in the responder group. Subsequent treatment was required in 15 nonresponders. There was no correlation between patients' subjective improvement and objective results. The study resulted in the following conclusions: 1. The responder rate to UPPP in unselected patients is low. 2. Obesity and high indices of nocturnal respiratory disturbance are negative predictors. 3. The patients' subjective recovery alone must not be used for postoperative evaluation. 4. With regular follow-up and the use of the treatment alternatives available today, the majority of OSAS patients can receive effective treatment.

Adult↗

PubMed2006

The effect of 1 week of continuous positive airway pressure treatment in obstructive sleep apnea patients with concomitant gastroesophageal reflux.

STUDY OBJECTIVES: Patients with obstructive sleep apnea (OSA) have a very high incidence of gastroesophageal reflux (GER). Previous studies have shown that the use of continuous positive airway pressure (CPAP) reduces the frequency of reflux events, but these studies only assessed the effect of a single night of treatment. The aim of this study was to assess the effect of 1 week of CPAP treatment on reflux in patients with OSA and GER. DESIGN: Sixteen patients with OSA and GER were recruited. Polysomnography followed by 24-h, continuous esophageal pH monitoring were performed at baseline. Patients with an apnea-hypopnea index (AHI) > 20/h and 24-h acid contact time (ACT) of at least 6% were included. As part of the polysomnography-qualifying evaluation, all patients underwent CPAP titration to reduce the AHI to < 10/h. Patients were then sent home receiving nasal CPAP for 1 week; after 1 week, esophageal pH monitoring was repeated while receiving CPAP. MEASUREMENTS AND RESULTS: The AHI fell from 63.3 +/- 38.5 to 3.2 +/- 2.2/h (mean +/- SD) [p < 0.001]. Total ACT fell from 13.9 +/- 11.6 to 5.6 +/- 2.7% (p < 0.001). The upright ACT was reduced from 12.4 +/- 6.8 to 6.8 +/- 3.8% (p = 0.01), and the supine (during the sleeping interval) ACT was reduced from 16.3 +/- 18.8 to 3.8 +/- 7.6% (p < 0.01). Eighty-one percent of the patients had a reduction in supine ACT to within the normal range (< 4%). CONCLUSIONS: In OSA patients with significant heartburn complaints, CPAP would appear to be an efficacious approach to the treatment of both disorders.

Adult↗

PubMed1984

Obstructive sleep apnea and body weight.

A patient with obstructive sleep apnea was monitored five times during three years while his weight fluctuated within a range of 26 kg. The number of apneas per hour of sleep varied from 59.6 at 111 kg of weight to 3.1 at 85 kg. The relation between apneas per hour of sleep and body weight was a logarithmic function. A modest decrease in weight was thus associated with a disproportionally larger decrease in the rate of apneas. Typical SaO2 levels during the apneic episodes also had a logarithmic relation with body weight. Apnea-related sinus bradycardia and sinus tachycardia were only present at the highest weight. The results suggested that dieting and weight loss lead to an improvement in sleep apnea and related sequelae.

Body Weight↗

PubMed2002

Health care services utilization in children with obstructive sleep apnea syndrome.

OBJECTIVE: Little is known about the effects of obstructive sleep apnea syndrome (OSAS) on utilization of health care services in children. The present study compares medical service utilization by children with OSAS with that of healthy children. METHODS: A cross-sectional study of 287 consecutively recruited children (1-18 years) with OSAS and no concomitant diseases and a control group matched by age, gender, and geographic location was conducted at the Clalit Health Care Services clinic in the southern region of Israel. Children in the study group underwent nocturnal polysomnography (PSG) studies. The control group (N = 1149) was randomly selected from the Clalit Health Care Services database. PSG was performed for the OSAS patients. Indices of health care utilization 1 year before the PSG study were analyzed. RESULTS: A 226% increase in health care utilization was noted among children with OSAS. Children up to 5 years of age consumed more health care resources than children over 5 years. Children with OSAS consumed more health care services than the control group at all ages. The leading components of this high cost are utilization of more hospital days, drugs, and visits to the emergency department. The severity of the OSAS correlates directly to total annual costs and independently to age (beta = 0.19). CONCLUSIONS: Children with OSAS are heavy consumers of health care services 1 year before any specific evaluation and treatment for apnea. Early diagnosis and intervention may be cost-effective.

Age Factors↗

PubMed2000

Accuracy of oximetry with thermistor (OxiFlow) for diagnosis of obstructive sleep apnea and hypopnea.

OBJECTIVES: To evaluate the diagnostic accuracy for obstructive sleep apnea and hypopnea (OSAH) of the OxiFlow (OF) device which combines oximetry with recording of thermistor airflow. DESIGN & SETTING: Patients scheduled for overnight diagnostic polysomnography (PSG) were studied with OF either simultaneously during laboratory PSG (L-OF, n=86), at home on a separate night (H-OF, n=66), or both (n=55). PATIENTS: 97 patients with suspected OSAH, of whom 40 had OSAH defined as an apnea-hypopnea index (AHI) of more than 15 events per hour of sleep on PSG. INTERVENTIONS: NA. MEASUREMENTS & RESULTS: The automated respiratory disturbance index (RDI) generated by the OF software considerably underestimated the AHI by PSG for both L-OF and H-OF. Altering the parameters for hypopnea identification by the software did not improve this. Visual inspection of the computerized OF tracings added considerable diagnostic information, but a manual count of RDI during visual review overestimated AHI. For the identification of cases vs. non-cases of OSAH, receiver operating characteristic area-under-the-curve statistics ranged from 0.77-0.90 for L-OF and from 0.71-0.77 for H-OF. Combining automated analysis with subsequent visual inspection of OF tracings yielded an overall sensitivity of 86% and specificity of 74% for the diagnosis of OSAH during H-OF recordings. Analysis of potential technician time saved indicated a benefit from the use of OF. CONCLUSIONS: OF has diagnostic utility for the identification of OSAH. However, because of hardware and software limitations, it is unclear whether this device is superior to oximetry alone.

Adult↗

PubMed2002

Gender and obstructive sleep apnea syndrome, part 2: mechanisms.

Epidemiologic studies have reported that obstructive sleep apnea syndrome (OSAS) is a common disorder affecting about four percent of adult males and two percent of adult females. This difference in OSAS prevalence suggests that the female gender may reduce the risk of sleep breathing disorders in adults. We review several interrelated factors that may explain the differences in risk related to gender. These include differences in obesity and the distribution of adipose tissue, upper-airway anatomy, upper-airway muscle function, control of ventilation, the effect of sex hormones and leptin. The gender related protective effect decreases in females who are postmenopausal and not on hormone replacement therapy.

Adipose Tissue↗

PubMed2003

[Clinical study of uvulopalatopharyngoplasty treatment for middle degree of obstructive sleep apnea syndromes].

OBJECTIVE: In order to investigate the treatment of obstructive sleep apnea syndrome (OSAS) METHOD: The improved uvulopalatopharyngoplasty (UPPP) operations were performed on 64 cases. RESULT: The clinical results showed that 70. Thirty-one percent of the operated patients somewhat improved and 29. Seventy percent unimproved. CONCLUSION: UPPP is one of the effective methods to treat OSAS, especially for OSAS with stricture in pharyngeal cavity. It has less damage, less operative complications and so on.

Adult↗

PubMed1992

[Long-term effects and complications of home nasal CPAP therapy for obstructive sleep apnea patients].

We treated 23 patients with obstructive sleep apnea syndrome (OSAS) by nasal continuous positive airway pressure (NCPAP) at home, and examined the long-term compliance, clinical effects, and complications after NCPAP therapy. Nineteen patients continued and four patients discontinued the therapy during the mean observation period of 15 months, and the compliance was 83%. There was no significant difference in age, weight, and sleep data between the compliant group (C) and non-compliant group (NC). The causes of discontinuation of therapy were lack of adaptation to the apparatus (2 cases), improvement of clinical symptoms due to weight reduction (1 case), and induction of asthma attack (1 case). Disappearance of excessive daytime sleepiness, improvement of sleep quality, and disappearance of nocturia were observed in most cases, and disappearance of morning headache and improvement of sexual ability and emotional instability were also observed in several cases. Nine cases (39%) complained of discomfort due to the nasal mask and 6 cases (26%) complained of dryness of the mouth and nose, whereas 10 cases (43%) experienced no adverse effects. No serious complications were observed. These findings suggest that long-term home NCPAP is an effective and safe treatment for OSAS patients.

Humans↗

PubMed2003

[Perioperative continuous positive airway pressure therapy for severe obstructive sleep apnea hypopnea syndrome patients].

OBJECTIVE: (1) To investigate the severe obstructive sleep apnea hypopnea syndrome (OSAHS) patients' perioperative variations of their polysomnographic indices, to discuss the necessity for their perioperative treatment; (2) To investigate the effects of continuous positive airway pressure (CPAP) on severe OSAHS patients during their perioperative period. METHODS: (1) 21 cases severe OSAHS patients were selected for at least 7 days preoperative CPAP therapy, and this group of patients were also given 3 continuous nights autotitrated CPAP (AutoSet) therapy postoperatively, i.e., the first 3 nights after operation. The 21 cases were remonitored with PSG during the second night after operation with their AutoSet ON. And all the 21 cases had revised uvulopalatopharygoplasty, in which the uvula is reserved completely. All patients apnea hypopnea index(AHI), lowest SaO2 (LSaO2), and sleep structure indices were calculated. (2) Another 24 cases of severe OSAHS patients without preoperative CPAP therapy or tracheotomy were selected as the control group, all patients received polysomnography (PSG) on the second night postoperatively. RESULTS: (1) 6 cases' condition of the control group got worse during the second night after operation, their LSaO2 are lower and their AHI got higher than pre-operation. For the another 18 cases, their condition got better than before operation. (2) 21 cases' AHI and LSaO2 are 61.1 +/- 9.9, 65.0% +/- 9.6% respectively before CPAP treatment, and the AHI and LSaO2 are 2.2 +/- 1.4, 94.5% +/- 2.9% during CPAP therapy. P < 0.001 (TTEST). All the 21 cases main symptoms disappeared after 1 week CPAP therapy. All 21 cases could tolerate AutoSet treatment well for the first 3 nights after operation. During the 2nd night with AutoSet therapy, the AHI and LSaO2 are 3.6 +/- 1.8 and 93.7% +/- 3.4% respectively. (3) For the 2nd night after operation, the CPAP and AutoSet treating group's AHI is lower than that of the control group, also the LSaO2 is higher, the deep and REM sleep stages are longer, and the S1, S2 sleep stages are shorter than that of the latter. CONCLUSION: For severe OSAHS patients, the postoperative condition has the possibility of getting worse. Perioperative CPAP therapy can have OSAHS patients severe condition alleviated, so the perioperative risks could be lowered; During the first 3 postoperative nights, AutoSet can be well tolerated by severe OSAHS patients.

Adult↗

PubMed1992

Management of obstructive sleep apnea.

Although the indications for treatment of obstructive sleep apnea are controversial, there is general agreement that treatment is warranted in patients with a combined apnea and hypopnea frequency of 20 events per hour of sleep. General therapeutic measures include abstinence from alcohol and weight loss in obese patients. A minority of patients with specific abnormalities of the nose, pharynx, or jaw may require surgical management. In the absence of specific upper airway abnormalities, the most effective treatment is nasal continuous positive airway pressure or, if necessary, bilevel positive airway pressure during sleep. The role of uvulopalatopharyngoplasty remains controversial, due in part to the reported variability in long-term efficacy of this procedure. Drug therapy may be effective in selected patients.

Humans↗

PubMed2005

[An experimental study on the mini pig model of obstructive sleep apnea syndrome].

A mini pig model for study of human obstructive sleep apnea syndrome (OSAS) was established by altitude hypoxia. Eight mini pigs were randomly assigned to 3 groups, named A, B, and C. They were placed in a double-roomed altitude chamber. As control, Groups A lived in Room 2 and there was an altitude of sea level in it. Groups B and C were in Room 1 and the pressure in it was 53.9 KPa with an oxygen concentration of 10.0%-11.2%. All of these mini pigs were in their rooms for 6 hours per day. Pigs in Groups B were in the room for 12 consecutive days and sacrificed on the 13th day. Pigs in Groups A and C were executed on the 23rd day. The pharyngeal CT scanning and the defermination of respiratory pressure in pharynx oralis and saturation of arterial blood oxygen were conducted in all exprimental mini pigs before they were put in chamber and before they were put to death. The pharyngeal tissues of the executed pigs were pathologically examined. CT scanning revealed there was significant (P < 0.05) increase in mini pigs' posterior pharyngeal wall (8.8 +/- 1.1 vs 6.5 +/- 0.6) and lateral pharyngeal wall (8.1 +/- 0.2 vs 6.3 +/- 0.6) on the 13th day as compared with that before they were put in chamber, and there was also significant (P < 0.05) increase (9.2 +/- 1.2 vs 6.3 +/- 0.7; 8.9 +/- 0.7 vs 6.4 +/- 0.5) on the 23rd day. There was significant (P < 0.05) reduction in diameter from left to right at the hyoid bone level (7.6 +/- 1.4 vs 9.7 +/- 1.4) and in the anteroposterior diameter at the soft palace level (3.8+/-1.1 vs 6.5 +/- 1.3) on the 13th day as compared with that before the mini pigs were put in chamber, and there was also sinificant (P < 0.05) reduction (6.4 +/- 1.6 vs 9.3 +/- 1.5; 4.3 +/- 0.9 vs 5.9 +/- 0.8) on the 23rd day. There was significant reduction (P < 0.05) in anteroposterior diameter on the posterior area of hyoid bone (3.7 +/- 0.9 vs 6.4 +/- 0.6) on the 23rd day. A significant change (P < 0.05) was observed in respiratory pressure of pharynx oralis on the 23rd day (0.0755 Mv) when compared with that before the first day (0.0658 Mv) in chamber and no significant change was seen on the 13th day. The saturation of blood oxygen decreased from 96.3% to 87.0% on the 13th day (P < 0.05) and further descended to 88.5% on the 23rd day (P < 0.05), compared with that before the first day in chamber. Pathological examination showed. In Group A, the mucosa of pharynx is covered by nonkeratinized-stratified squamous epithelium, and the layer of submucosa is thin; the muscular layer has clear striations and less fat cells among muscular fibers. In Group B, the pharyngeal epithelium is cornified and proliferated. Edema and proliferation of connective tissue occur in submucosa, and the muscular layer is thick with unclear striations; local infiltration of fat cells can be observed among muscular fibers. The pathological changes were more serious in Group C than in Group B. The results suggest that the method of intermittent altitude hypoxia could make the pharyngeal tissue of mini pig remodel and change its muscular biomechanical properties into those similar to the performance of OSAS in human. Living in altitude hypoxia for 22 days, the mini pigs became ill with OSAS, thus the expected animal model has been established in this study and could be used in further researches on OSAS in patients.

Altitude↗

PubMed2006

Comparison of tongue volume/oral cavity volume ratio between obstructive sleep apnea syndrome patients and normal adults using magnetic resonance imaging.

Obstructive sleep apnea syndrome (OSAS) is a group of disorders in which breathing stops intermittently and repeatedly for 10 seconds or more during sleep. The causal site of the disorders is thought to be in the upper airway above the glottis. In order to understand the three-dimensional features of the oral and peripharyngeal structures involved in the disorders, we calculated the tongue volume/oral cavity volume ratio (TV/OCV ratio) in the oral cavity using magnetic resonance imaging (MRI) for both OSAS patients and normal controls. The study subjects comprised 20 male patients with OSAS (apnea-hypopnea index [AHI] > or = 5.0, with a diagnosis of OSAS) and 20 normal male adults (AHI<5.0, with no history of OSAS) as the controls. We performed MRI to acquire T1- and T2-weighted images. We estimated tongue volumes on the basis of the cross-sectional area of each image, then using the tongue volume data, we calculated TV/OCV ratios. In the normal control group, mean (+/- SD) body mass index (BMI) was 21.68 +/- 1.73 and the mean TV/OCV ratio was 86.98 +/- 3.16%, whereas these values were 25.0 +/- 15.94 and 90.56 +/- 2.15%, respectively, in the OSAS patient group. The TV/OCV ratio of the OSAS patient group was significantly higher than that of the normal control group (p<0.01).

Adult↗

PubMed1994

Obstructive sleep apnea. Warding off the sometimes dire consequences.

Obstructive sleep apnea (occlusion of the upper airway despite continued respiratory muscle activity) is accompanied by increased morbidity and mortality from cardiovascular and cerebrovascular disease. Daytime sleepiness due to the disorder may also be a factor in a higher incidence of automobile accidents in these patients. An overnight polysomnogram is used to confirm the diagnosis and assess severity of physiologic disturbances. Initially, simple measures, such as avoidance of alcohol and sedatives before bedtime and sleeping on the side rather than the back, may be tried. Nasal continuous positive airway pressure is considered first-line therapy, and compliance can be improved by education and counseling of the patient. Uvulopalatopharyngoplasty is beneficial in only 50% of patients. Tracheostomy gives the most consistent long-term benefit but is accompanied by significant emotional morbidity.

Humans↗

PubMed1995

[Effect continuous positive airway pressure (CPAP) on left ventricular diastolic function in patients with obstructive sleep apnea syndrome--OSAS].

22 patients with (OSAS) obstructive sleep apnea syndrome were divided into two groups: patients with OSAS and without arterial hypertension, and OSAS with hypertension. The effect of CPAP (continuous positive airway pressure) on the left ventricular function was evaluated using 2D and Doppler echocardiography. Systolic left ventricular function (ejection fraction) was normal in all patients. The decrease in peak mitral flow velocity during early diastole E (m/sec), the increase of atrio-systolic contraction A (m/sec), the increase in E/A and prolonged isovolumic relaxation time (IVRT) was observed in the both groups at the beginning of the study. After three month treatment with CPAP the increase in the ratio E/A, 1.38 + 0.23 m/sec vs 0.98 + 0.28 (p < 0.05) and a reduction in IVRT, 79 + 6.8 milisec vs 91.3 + 6.3 (p < 0.05) in the group with OSAS and hypertension was observed. In the group with OSAS and without hypertension only a statistically significant reduction in IVRT was observed, 77.8 + 5.4 vs 83.7 + 5.15 milisec p < 0.05.

Adult↗

PubMed2005

Obstructive sleep apnea syndrome and the pulmonary circulation.

The pulmonary hemodynamic consequences of obstructive sleep apneas have been investigated by several groups during the last 30 years. The earlier data have been obtained by measuring the intravascular pulmonary arterial pressure (PAP) and have shown a rise of PAP during apneas, the highest PAP being observed at the end of apneas. Actually, during obstructive apneas the only reliable measurements are those of transmural PAP which increases throughout the apneas, as a consequence of hypoxic vasoconstriction, and decreases after ventilation has resumed. The link between episodic (nighttime) and permanent (daytime) pulmonary hypertension is poorly understood. Recent studies have clearly indicated that daytime hypoxemia, generally due to an associated chronic airflow obstruction, is the major determinant of permanent pulmonary hypertension and cor pulmonale, and that nocturnal hypoxemia is not sufficient per se.

Circadian Rhythm↗