INCREASING THE UPPER AIRWAY SPACE USING ORAL APPLIANCES IN PATIENTS WITH MILD SLEEP APNOEA CAUSED BY STOMATOGNATHIC DYSFUNCTIONS

INTRODUCTION

Abnormal breathing can be caused by developmental malformations or anatomical variations in the upper airways. Stomatognathic diseases may significantly impair the patency of the upper respiratory tract. Treatment of advanced stomatognathic dysfunctions is difficult due to their multifactorial aetiology, and often involves many phases. Sleep apnoea is one of the most bothersome complications. The mainstay therapeutic strategy relies on modifying the position of the mandible against the maxilla, achieved by using different types of oral appliances.

MATERIAL AND METHODS

The study was carried out in 2006-2010 on 92 patients (mean age 42.5 years) with diagnosed advanced dysfunction of the stomatognathic system. The treatment relied on the use of an orthodontic appliance (54 patients) or combined multi-phase therapy with splints used in the first phase (22 patients). Two different appliances were used (one of them was modified by the authors). Parameters assessed in the study included time to resolution of pain, reduction in the incidence of sleep apnoea, and improvement in nasal breathing.

RESULTS

Change in the protrusion of the mandible not only relieved problems with the stomatognathic system, but also improved breathing in patients. The use of modified oral appliances reduced treatment duration and improved patients' comfort. Therefore, it may be useful in the treatment of patients with mild sleep apnoea.

Orthodontic treatment in children to prevent sleep-disordered breathing in adulthood

The purpose of this article is to review human craniofacial growth and development, especially the growth of the mandible, to clarify the relationship between obstructive sleep apnea (OSA) syndrome and craniofacial abnormality, and finally, to propose the hypothesis that negative pressure produced in the chest of the OSA child inhibits the growth of the mandible. Recently, the development of diagnosis and treatment of OSA syndrome has progressed rapidly; however, the prevention of OSA syndrome was merely seen. Craniofacial abnormality is reported as one of the causes of OSA syndrome. If craniofacial abnormality is determined only by genetics, it is difficult to manage the craniofacial skeleton to prevent OSA syndrome. The role of epigenetic factors on craniofacial growth and development is still controversial. However, if we stand on the functional matrix hypothesis, we can manage not only growth of the mandible but also the craniofacial skeleton as a whole. The author proposes the hypothesis that the negative pressure produced in the chest prohibits the growth of the mandible even if the patients have a capacity for growth and development; therefore, if this negative pressure disappears because of the removal of the tonsil and/or adenoids or by an orthodontic treatment to make a patency of the airway, the mandible may grow normally, and we can prevent or reduce a number of OSA syndromes in the future.

Association of physical activity with sleep-disordered breathing

This study was performed to determine whether there is a protective association between participation in vigorous or vigorous/moderately vigorous physical activity and the prevalence of sleep-disordered breathing (SDB). Polysomnographic and questionnaire data from the baseline examination of 4,275 participants in the Sleep Heart Health Study (SHHS) were analyzed in relation to information on amount of physical activity and other potentially relevant factors collected from five SHHS parent cohorts (Atherosclerosis Risk in Communities Study, Cardiovascular Health Study, Framingham Heart Study, Strong Heart Study, and Tucson Epidemiologic Study of Airways Obstructive Diseases). Logistic regression models were fitted to determine if amount and strenuousness of physical activity was associated with the presence of SDB. At least 3 h per week of vigorous physical activity reduced the odds of SDB, defined as a respiratory disturbance index (RDI) of at least 15 apneas/hypopneas per hour (Adjusted OR, 0.68; 95%CI, 0.51-0.91). A qualitatively similar but slightly weaker association was observed when SDB was defined as a RDI > or = 10 per hour (Adjusted OR, 0.81; 95%CI, 0.64-1.02). These findings remained after adjustment for sleepiness and restricting analyses to participants with good health. Three or more hours of moderately vigorous or vigorous physical activity also appeared to confer some protection against SDB, but these associations were weaker. Gender- and obesity-stratified analyses suggested that the protective association between physical activity and SDB occurred primarily in men and those who were obese. A program of regular vigorous physical activity of at least 3 h per week may be a useful adjunctive treatment modality for SDB, but this association needs confirmation with a prospective clinical trial.

Interdisciplinary rehabilitation in morbidly obese subjects: an observational pilot study

BACKGROUND AND AIM

To assess the clinical effectiveness of a interdisciplinary rehabilitation programme (CR), in a population of morbidly obese subjects we have undertaken a observational study.

METHODS

The study included fifty-nine adult subjects (18 M, 60+/-10 years, BMI 47+/-8) with sleep-disturbance related symptoms and disabilities. Assessment and correction of sleep disordered breathing (SDB) abnormalities, improvement of exercise tolerance, body weight and associated psychological features were the aims of this CR, which has been carried out over a 1 month period. Lung functions, apnea/hypopnea index (AHI), 6-minute walking distance (6MWD), body weight (BW), quality of life by means of Sat-P questionnaire and serum metabolic data has been recorded at baseline (TO), at the end (Ti) and 6 months after (T2) the CR.

RESULTS

The percentage of patients with AHI > 10 declined from 65% (at TO) to 20% (at both T1 and T2). 6MWD and BW significantly improved (p < 0.005) at T1 and still maintained at T2; a significant relationship (r = 0.379, p < 0.01) has been found between changes of BW and 6MWD recorded in between TO and T2. Sat-P item scores dealing with sleep efficiency, problem solving, and social interactions improved (p < 0.01) at T1 and still maintained at T2.

CONCLUSIONS

This hospital-based CR provides indication for effectiveness in advanced morbidly obese subjects and warrants further controlled trials to confirm the results.

Efficacy and comorbidity of oral appliances in the treatment of obstructive sleep apnea-hypopnea: a systematic review and preliminary results of a randomized trial

The obstructive sleep apnea-hypopnea syndrome (OSAHS) is a common sleep-related breathing disorder characterized by repetitive obstructions of the upper airway during sleep. The modification of pharyngeal patency by oral appliance therapy has been suggested as an alternative to various treatment modalities for OSAHS. To determine the evidence base with respect to the efficacy and comorbidity of the oral appliance therapy in OSAHS, a systematic review of the available literature was conducted. In addition, the preliminary results of a randomized parallel trial are reported on the effectiveness and specific indication of, respectively, the oral appliance and continuous positive airways pressure therapy in OSAHS.

Polysomnography in hospitalized patients using a wireless wide area network

BACKGROUND

Sleep-disordered breathing and hypoxemia frequently underlie many common medical conditions for which patients require hospitalization. Sleep apnea is associated with adverse cardiovascular, neurovascular, inflammatory, and metabolic consequences, many of which can be reversed with nasal continuous positive airway pressure. Although polysomnography is the gold standard for outpatient evaluation of sleep apnea, it has not been used for establishing the diagnosis or as a means to intervene with evidence-based therapy in the hospital setting.

SETTING

A 468-bed tertiary-care facility for adults in which an 801.11b wireless network supplements a typical hardwired local area network.

METHODOLOGY

We developed a technique to perform 16-channel polysomnography on any patient in any location in the hospital without interfering with routine nursing care. Qualified sleep technicians are able to remotely adjust electrophysiologic and respiratory parameters, as well as control continuous positive airway pressure titration. The study can also be monitored from any location with Internet access using a HIPAA-compliant virtual private network.

RESULTS

Polysomnography was performed on 51 inpatients (age 26 to 89 years; 31 men). Mean (SD) body mass index measured 34.1 kg/m(2) (12.4). Cardiac disease (47%) and neurologic disease (27%) were the most frequent primary indications for admission. Data acquisition was not disrupted due to connectivity problems. The most frequent deficiencies were reduced sleep time (range 0.8-6.5 hours; mean [SD] 3.3 hours [1.6]) and reduced or absent rapid eye movement sleep. Mean (SD) apnea-hypopnea index measured 35.9 events per hour of sleep (SD 26.3) and 19.4 events per hour of total recording time (SD 17.5).

CONCLUSIONS

Polysomnography measurements transmitted across a wireless wide area network increases the capacity of the traditional hospital-based sleep laboratory. This technique can facilitate early implementation of appropriate therapy and may reverse underlying factors associated with the primary cause of hospitalization. Indications and standards of practice need to be specifically established for inpatient polysomnography.

Health care costs and the sleep apnea syndrome

This paper reviews some concepts on health economics from the authors personal perspective. It then examines the few papers published on health economics analysis applied to the field of sleep apnea syndrome, as well as the literature on the indirect (cost) consequences of sleep apnea syndrome. It appears that undiagnosed sleep apnea leads to a roughly two-fold increase in medical expenses in the years preceding the diagnosis and that treating the disease (once it is diagnosed) results in a decrease in these excess costs. It seems clear that sleep apnea increases the actual number of road traffic accidents, which will carry a definite, but unmeasured up to now, economic cost consequence. From the health economic point of view, the best diagnostic strategy is the one with the greater utility (i.e. polysomnography), although it could appear at first sight to be the more expensive one. From the patient's perspective, sleep apnea results in a given decrease in the possibilities to enjoy life, and its treatment is worth considering, especially if one takes into account that the actual treatment costs are not great. The global image of the health costs related to sleep apnea is still blurred, and further work is required to get the complete and clear picture of the economic consequences of this disease and of its treatment.

Resolution of Severe Sleep-Disordered Breathing with a Nasopharyngeal Obturator in 2 Cases of Nasopharyngeal Stenosis Complicating Uvulopalatopharyngoplasty

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is characterized by episodic decrements in airflow due to upper airway obstruction. Uvulopalatopharyngoplasty (UPPP) is a potential therapy for OSAHS. Nasopharyngeal stenosis is a rare complication of UPPP that worsens OSAHS. We report two patients referred for OSAHS worsened by nasopharyngeal stenosis complicating UPPP. Both patients were treated with carbon dioxide laser release of adhesions and placement of a nasopharyngeal obturator. Follow-up polysomnograms demonstrated resolution of OSAHS correlating with subjective resolution of symptoms. Nasopharyngeal stenosis complicating UPPP can be successfully treated with scar removal and nasopharyngeal stenting. Polysomnographic demonstration of the effectiveness of this therapy has not previously been reported. Future questions include duration of nasopharyngeal stenting and timing of follow-up polysomnography.

Kosten-Nutzen-Analyse bei Patienten mit schlafbezogenen Atmungsstörungen. Schlafmedizinische Diagnostik und nCPAP-Therapie während der medizinischen Rehabilitation. Cost-Benefit Analysis in Patients with Sleep-related Breathing Disorders - Diagnosis and nCPAP Therapy During Medical Rehabilitation

In a multi-centre study, 745 patients undergoing internal medical rehabilitation (for hypertension, coronary heart disease, gastrointestinal and respiratory diseases) were investigated. The health economic benefit was evaluated during the 3 weeks of medical rehabilitation, during which a sleep-medical diagnostic work-up and treatment were applied. Ambulatory screening for sleep-related breathing disorders was carried out in all patients. In positive cases (Apnoea-Hypopnoea Index > or = 10) transfer to our sleep lab was recommended. 103 patients were found to be positive, of whom 47 attended the lab; 23 of these accepted nCPAP therapy, while 24 did not. The costs of the additional diagnosis and treatment were considered incremental costs--and the benefit identified as the decrease in days off work as revealed by a comparison of the year before with the year after rehabilitation. Days off work decreased by 38.4 days in the treated group, and increased by 25.4 days in the untreated group. The results were extrapolated to all patients in internal medical rehabilitation in Germany, and a cost-benefit analysis showed that the benefit of expanding the additional investigation to cover all patients would far exceed the incremental costs in the first year after rehabilitation by 58.26 Mio [symbol: see text] and in the second year by 81.15 Mio. [symbol: see text].

[Endoscopically-assisted adjustment of an oral appliance in patients with obstructive sleep apnoea]

BACKGROUND

The treatment effect of patients suffering from obstructive sleep apnoea/hypopnea (OSAHS) with an oral appliance is considerably varied, and its clinical outcome is unpredictable. The aim of our investigation was to examine the changes in pharyngeal airway size at different degrees of mandibular protrusion in order to assess the therapeutic efficacy in relation to the amount of protrusion.

METHODS

Fifteen patients with the polysomnographic diagnosis of mild to moderate OSAHS were included in this prospective study. Nasal video endoscopy of the pharynx was done with the patients in supine position at four different degrees of mandibular protrusion do assess the changes of airway size. After 3 - 4 weeks a control polysomnography was carried out, with the mandible in optimal protrusion.

RESULTS

The pharyngeal diameter did not increase linearly to the amount of mandibular protrusion. In the polysomnographic examination the respiratory variables were significantly increased. None of the patients in this group was classified as a non-responder to the oral appliance therapy.

CONCLUSIONS

The endoscopically-assisted adjustment of the mandibular protrusion appliance is an additional tool to optimise treatment effectiveness. The increase in pharyngeal diameter is not proportional to the amount of mandibular protrusion.

Resistive inspiratory muscle training in sleep-disordered breathing of traumatic tetraplegia

OBJECTIVE

To assess the effect of resistive inspiratory muscle training (RIMT) on the static pulmonary function and sleep-induced breathing disorder of individuals with chronic cervical cord injury.

DESIGN

Before-after training.

SETTING

Home-setting training program.

PATIENTS

Fourteen complete traumatic tetraplegic patients (12 men, 2 women; mean age, 41.1 +/- 14y; range, 19-56y) injured for more than 6 months.

INTERVENTION

Subjects participated in a 6-week RIMT program for 15 minutes twice daily at a training intensity of 60% of maximum inspiratory pressure (MIP). The participants were reevaluated at the end of 6-week training.

MAIN OUTCOME MEASURES

Lung volume, peak expiratory flow (PEF), MIP, and maximum expiratory pressure (MEP) were measured by using a spirometry and inspiratory force meter, respectively. Capnography was used to monitor nocturnal pulse oxyhemoglobin saturation (SpO(2)) and end-tidal carbon dioxide tension level (ETCO(2)) of the patients.

RESULTS

The maximum voluntary ventilation (MVV) and MIP of individuals with chronic cervical cord injury substantially improved after RIMT. MIP increased from -68.7 +/- 27.4cmH(2)O to -77.3 +/- 24.0cmH(2)O and MVV rose from 62.7 +/- 33.2L to 73.4 +/- 31.3L (P <.05). Despite increasing from 3.5 +/- 1.8L/s to 4.0 +/- 1.7L/s, PEF was statistically insignificant. For the individuals with improved MIP, the duration of ETCO(2) greater than 48mmHg reduced from 2.2% +/- 3.3% to 1.0% +/- 2.0% of total sleep time (P =.05) and that of SpO(2) less than 90% significantly declined from 1.8% +/- 2.8% to 1.3% +/- 2.4% of total sleep time (P <.05).

CONCLUSION

These findings suggest that RIMT can enhance the respiratory muscle strength and endurance of chronic tetraplegia and further ameliorate the sleep-induced breathing disorder. Therefore, RIMT is suggested as a home program for patients with sleep-disordered breathing.

Cervical positional effects on snoring and apneas

We examined the effects of cervical position on the Obstructive Sleep Apnea Syndrome (OSAS) through the use of a custom-designed cervical pillow which promoted neck extension. Twelve subjects with OSAS were recruited from a tertiary sleep disorder clinic population. Of the twelve subjects, three had mild cases of OSAS, four had moderate cases, and the remaining five had severe cases. The subjects used their usual pillows during two consecutive recorded baseline nights in our laboratory. The subjects then used the cervical pillow for five days at home, and returned for two consecutive recorded nights at our laboratory while using the cervical pillow. During the nights in our laboratory, the subjects completed questionnaires, were videotaped to record head and body position, and had their breathing parameters recorded during sleep. Subjects with mild OSAS cases had a non-significant improvement in the severity of their snoring and a significant improvement in their respiratory disturbance index with the cervical pillow, while subjects with moderate OSAS cases showed no improvement in these parameters. Subjects with severe OSAS cases showed slight improvement in some measures of their abnormal respiratory events during the experimental period.

Mild to moderate sleep respiratory events: one negative night may not be enough

STUDY OBJECTIVES

Reports on the reproducibility of apnea-hypopnea indexes (AHIs) across sequential polysomnography (PSG) sessions are conflicting, leading to a lack of clear recommendations on the optimal use of this technique: is one night of monitoring sufficient or is a second night required in order to safely reject the diagnosis?

DESIGN

Retrospective comparison of two consecutive nights.

SETTING

Sleep unit of a tertiary-care facility.

PATIENTS

Two hundred forty-three subjects with suspected sleep apneas.

INTERVENTIONS

Two sequential PSG sessions in a sleep unit.

MEASUREMENTS AND RESULTS

Using analysis of covariance for repeated measures, with age and body mass index as covariates and gender as a cofactor, a classic first-night effect was found for sleep variables. In addition, a night effect was demonstrated for sleep respiratory variables. Moreover, the high variability of AHIs showed that many patients had their condition diagnosed on only one of the two nights, and more often on the second night than on the first. The gain in detection by adding a second night when the results of testing on the first were negative was between 15% and 25%, according to the AHI obtained on night 1.

CONCLUSIONS

Considering the disability associated with sleep apnea/hypopnea syndrome, as well as its global cost for society, the present study shows that it is worth performing two consecutive PSG sessions or at least a second one when the result of the first one is negative in all patients admitted for apnea detection.

The anterior mandibular positioning device for the treatment of obstructive sleep apnoea syndrome: experience with the Serenox

Anterior mandibular positioning devices are seldom used at present in the treatment of obstructive sleep apnoea syndrome (OSAS). The aim of our study was to evaluate the efficiency, the side-effects and the patient compliance with one type of device made in Switzerland, the Serenox. This device is designed to keep the mouth closed with the mandible forward, avoiding the vibration of the soft palate. Between January 1996 and October 1997, 15 patients with OSAS were treated using a Serenox. One of them stopped using the device after 6 weeks due to the persistence of temporomandibular joint pain. Serenox was successful in 13 of the remaining 14 patients. The median pretreatment apnoea/hypopnoea index (AHI) of 36.25/h was decreased to 5.5/h after treatment (P < 0.002). Snoring and daytime sleepiness were notably reduced. The side-effects were frequent but mild and disappeared after a few weeks of adaptation. In conclusion, 87% (13/15) of the patients were treated successfully. Indications for the use of a mandibular positioning device include snoring, upper airway resistance syndrome and light to mild OSAS without severe obesity.

Multiple cardiovascular risk factors in obstructive sleep apnea syndrome patients and an attempt at lifestyle modification using telemedicine-based education

Severe obstructive sleep apnea syndrome (OSAS) is a typical 'lifestyle-related disease' characterized by a high incidence of cardiovascular risk factors, such as obesity, smoking, hypertriglyceridemia, and diabetes mellitus. Patients with OSAS tend to have eating disorders as a result of efforts to overcome the intolerable sleepiness. Treatment of OSAS should therefore aim to improve the lifestyle through encouraging weight reduction, physical activity increase, and tobacco avoidance, in addition to direct therapy such as continuous positive airway pressure for upper airway obstruction. The telemedicine system we developed was considered to be effective for providing home-based education on nutrition and exercise aimed at correcting multiple risk factors in OSAS patients

[Intra-oral therapy of borderline sleep-related respiratory disorders with a modified protrusion-fixation of the mandible]

BACKGROUND

Aim of this study was the investigation of the efficacy and acceptance by mechanic-prosthetic mandibular protrusion for patients with mild to moderate OSAS.

METHODS AND PATIENTS

During interdisciplinary teamwork between pneumology (sleep medicine) and dentistry we studied the change in the apnoea-index (AI) of 21 unselected patients treated with a modified oral appliance according to Lyon using less protrusion of the mandible and individual occlusion of the jaws. All patients were asked to rate their complaint-score using the oral appliance.

RESULTS

21 patients--aged 55.03 +/- 9.71 years; body mass index (BMI) 28.6 +/- 2.4 kg/m2 (mean value +/- SD)--had an improvement of apnoea-index (1/h) high significant (p < 0.0005). (Al before therapy 15.25 +/- 6.6; Al with therapy 6.07 +/- 3.7). Using a validated ambulatory respiratory evaluation device we saw an improvement in the Al of 57% +/- 19% during the estimated sleeptime of 6 h 12 min +/- 30 min. After a wearing-time of about 6 months the low complaint-score of the patients verified the high acceptance and efficacy of the modified oral appliance.

CONCLUSION

The modified oral appliance of Lyon can improve disease severity, life- and sleep-quality of patients with mild to moderate OSAS. Engaged teamwork of sleep medicine and dentistry is necessary to take care of a very individual and carefully fixation and occlusion of the mandible, resulting a continuing compliance and efficacy for the patients.

[Influence of the Esmarch splint on chewing and tongue muscle activity during sleep]

To clarify the functional mechanism of the Esmarch device in the treatment of sleep apnea, its effect on muscle activity during sleep was studied electromyographically with and without the appliance at the inferior head of the lateral pterygoid muscle, the genioglossal muscle, and the masseter muscle in 15 patients with sleep apnea syndrome. During the obstructive apnea the muscles showed significantly lower amplitudes than before the apnea. No significant decrease in the amplitude was observed during the central apnea, but, after the obstructive and central apnea, significantly higher amplitudes were seen than beforehand. The amplitudes rose after the placement of the appliance, and the amplitudes of the genioglossal and lateral pterygoid muscles during obstructive apnea increased significantly after the insertion of the appliance. The results suggest that the device can activate the masticatory and tongue muscle activity and indicate that the muscles activated with the appliance can prevent obstruction in the oropharynx. The Esmarch device not only helps avoid obstruction by mandibular protraction, but also affects function by activating the muscles.

Effectiveness of prosthetic mandibular advancement for obstructive sleep apnea: analysis by sleep position

Fifteen patients with obstructive sleep apnea were treated using prosthetic mandibular advancement (PMA). Each patient was evaluated in the supine and lateral decubitus positions with and without PMA. After PMA treatment, the mean intraesophageal pressure (Peso) in the supine position improved from -42.6 to -27.3 cmH2O and the mean apnea + hypopnea index (AHI) decreased from 48.8/h to 23.7/h. The mean Peso in the lateral decubitus position improved from -27.9 to -18.6 cmH2O and the mean AHI decreased from 9.6/h to 6.6/h. With PMA, respiratory, disturbance during sleep further improved by changing the body position from the supine to lateral decubitus position.

Mechanism of action and therapeutic indication of prosthetic mandibular advancement in obstructive sleep apnea syndrome

Prosthetic mandibular advancement (PMA) was applied to nine patients with obstructive sleep apnea syndrome (OSAS) and its therapeutic usefulness, mechanism of action, and clinical indication were discussed based on polysomnographic findings and serial examination of upper airway before and during PMA treatment. Apnea hypopnea index significantly decreased during PMA treatment compared with the value before treatment (P < 0.01) and the rate of the treatment responder counted 78.1%. Cephalometric variables indicated forward and inferior advancement of mandible in our subjects. Magnetic resonance imaging of the upper airway during sleep revealed a marked improvement of velophanryngeal obstruction in most subjects. In addition, intraesophageal negative pressure during sleep decreased significantly. Our results confirmed the high therapeutic efficacy of PMA for OSAS and indicated forward advancement of the mandible and decrease of negative pressure loading on upper airway with PMA might suppress velopharyngeal collapse. Thus, PMA was regarded as one of the treatments of choice for OSAS occurring based on with velopharyngeal narrowing.

Changes in work performances in obstructive sleep apnea patients after dental appliance therapy

The effects of dental appliances on work performances of obstructive sleep apnea syndrome (OSAS) is not well examined. This study evaluated the polysomnographic and psychological findings before and after therapy. Nine patients were diagnosed OSAS by nocturnal polysomnography. The psychological batter, was performed from 13:00 to 14:00, which consisted of Uchida-Kraepelin psychodiagnostic test (U-K's test) and Bourdon's cancellation test (Bourdon's test). Approximately 3 months after the treatment, the examinations were performed. Apnea and desaturation index decreased significantly after the therapy. In addition, sleep architecture improved after the therapy compared with that before the therapy. Dysfunction of task performances, such as mean level of work amounts in U-K's test, mean error, mean performance time and mean deviation in Bourdon's test improved after therapy. We conclude that dental appliances therapy is effective not only to apnea but also to work performance in OSAS.

Oral appliances in the treatment of snoring and sleep apnea

Oral appliances have been developed that are effective in snoring patients and in patients with mild to moderate sleep apnea. This article reviews the types of appliances that are available, their possible modes of action, and their efficacy. In addition, the clinician is provided with guidelines on how to choose the appropriate patient for this therapy.

[Physical training of patients with sleep apnea]

PURPOSE

It is a common question of sleep apnoea patients in the sleep lab whether they stand a chance to decrease the symptoms and severity of their disease by physical exercise. As far as we know, there is no data about this specific question until now, even though this has been subject to speculation. A few studies, however, report on an improvement of the respiratory drive (and chemoreceptor sensitivity) after physical exercise in athletes. The aim of this study was to prove whether physical exercise in sleep apnoea patients could improve the symptoms of their disease in an open trial.

METHODS

11 Patients with mild to severe sleep apnoea syndrome (1 f, 10 m, mean age 53.8x) took part in a 6-month period of physical exercise twice a week 2 h each time under the instructions of physical therapists. Before and after the 6mo period a full PSG without CPAP or BIPAP, a bicycle exercise test with lactate profile, echocardiography, blood test, and body weight and body height measurement was performed. Statistical analysis was done using Wilcoxon ranked test and multiple regression analysis.

RESULTS

There was no significant bodyweight reduction in all patients after the 6mo period of physical training, no significant difference in either basal SaO2 nor mean SaO2 and no significant improvement in physical status by the p at 4 mmol lactate on the lactate profile. Echocardiographic changes were not found; there was no significant change in the blood pressure profiles during the bicycle test. No cardiopulmonary problems including exercise-induced high blood pressure were reported during the training period. There was, however, a significant decrease of the RDI (p < 0.05), but no significant change in the REM-sleep % of total sleep time (TST) and the TST itself.

CONCLUSIONS

There was an improvement of the sleep apnoea syndrome correlated to a decrease of the RDI in the studied patient population due to a possible increase in the respiratory drive or a stabilised muscle tone ine the upper airways after physical exercise, as reported by other authors, because weight reduction could not be the reason in our patients. Our trial showed that the exercise does not increase the severity of symptoms of sleep apnoea by changing the REM/non REM ratio or for any other reasons. A physical training programme for sleep apnoea patients as an additional treatment should therefore be considered.

[Value of various intra- and extraoral therapeutic procedures for treatment of obstructive sleep apnea and snoring]

BACKGROUND

Recently intra- and extraoral devices are increasingly used in order to treat obstructive sleep apnea (OSA) and snoring. We examined the value of some devices according to the literature and our own results.

PATIENTS AND METHODS

The mandibular advancing devices aim at increasing upper airway diameter. The active part of the tongue extending device (SnorEx) is a stamp connected to a piston which exerts pressure at the base of the tongue causing its forward displacement; we studied 23 patients. The principle of an optically stimulating system ("eye-cover", Snore-Stop) consists of a microphone and light diods which are integrated in the eye-cover. After detecting acoustic signals (for example snoring) optical stimuli are generated in front of the eyes, which are thought to induce arousals causing a change of body position and the reduction of the snoring and apneas; we measured 24 patients. The principle of the tongue-retainer (Snore-Master) is the fixation of the tongue in a ventral position, which is thought to enlarge the mesopharyngeal area; we studied 14 patients. The nose plaster (Breathe-Right) contains an elastic spine that pulls the alae nasi cranial. This manipulation is thought to increase the diameter of the nostril and reduce the airway resistance. We measured 30 patients with obstructive sleep apnea and 20 snoring subjects without obstructive sleep apnea.

RESULTS

Regarding the mandibular advancing due to different appliance designs and study protocols variable success rates have been documented. In patients with mild to moderate obstructive sleep apnea a reduction of the sleep related breathing disorder could be shown. Non compliance (NC) to the tongue extending device was 75% (17/23). Non-compliance-patients were characterized by unacceptable local-side-effects of the prosthesis, lacking improvement of symptoms and of the respiratory disturbance index. Both tongue-retainer and -extensor are characterized by a high incidence of local side effects. Neither the eye-cover nor the nose plaster could improve the severity of obstructive sleep apnoe or snoring. In contrast to another study we could not show a significant effect of the tongue-retainer.

CONCLUSIONS

Neither the nose plaster nor the optical stimulating device influenced the degree of obstructive sleep apnea and snoring. There are conflicting data regarding the tongue retainer. The high rate of non-compliant subjects and the low efficacy of the tongue extending prosthesis precludes large-scale use of this treatment modality in patients with obstructive sleep apnoe and snoring. In selected individuals suffering from a mild to moderate degree of obstructive sleep apnea with CPAP-inefficiency and -incompliance the mandibular advancing principle may be an therapeutic alternative to CPAP.

The mandibular repositioning device: role in the treatment of obstructive sleep apnea

The role of oral appliances in the routine treatment of obstructive sleep apnea (OSA) is not well defined. This prospective study attempts to clarify the clinical role of a specific oral appliance, the mandibular repositioning device (MRD). This study evaluated the demographic, polysomnographic, and cephalometric radiographic findings predictive of treatment success or failure with the MRD. Twenty-nine patients were diagnosed with mild to severe OSA by nocturnal polysomnography. The majority of these patients were intolerant to nasal continuous positive airway pressure (CPAP) and all were fitted with a MRD. Twenty-three of these patients were compliant initially with MRD use and received post-treatment nocturnal polysomnogrpahy at a mean of 104 days after receiving the device. The respiratory disturbance index (RDI) decreased with MRD use (37 +/- 23 versus 18 +/- 20 events/hour, p < 0.001), and 16 of the 23 patients (69%) were considered responders (decrease in RDI > or = 50% and posttreatment RDI < or = 20). Measurements of subjective and objective daytime sleepiness, nocturnal oxygen desaturation, and snoring were all improved with MRD use. A pre-treatment RDI > 40 was present in four of the seven (67%) non-responders. Age, body mass index, and cephalometric radiographic measurements were not predictive of treatment outcome. Sixteen of 23 patients (70%) continue to use the MRD after 3.4 +/- 0.7 years. This study suggests that the MRD is useful in the long-term treatment of patients with OSA of mild to moderate severity.

Oral appliance therapy for the treatment of obstructive sleep apnea

A variety of oral appliances (OA) are now available for the treatment of obstructive sleep apnea (OSA), OA therapy is effective in some patients with mild to moderate OSA and is associated with greater patient satisfaction than nasal CPAP. Adjustable OA are associated with improved treatment success and fewer compliance failures compared to non-adjustable OA. Large randomized clinical trials are necessary to further determine the precise indications, benefits, and risks of each OA in the treatment of OSA.

Tiredness and somnolence despite initial treatment of obstructive sleep apnea syndrome (what to do when an OSAS patient stays hypersomnolent despite treatment)

From a database of 4,129 patients with sleep-disordered breathing (SDB), we found 207 subjects (43 women) that still complained of daytime tiredness, fatigue, and/or sleepiness despite treatment. In 25 subjects the sleepiness developed 1 to 36 months following treatment and was related to noncompliance (8 subjects), significant weight increase and/or inappropriate treatment (10 subjects), or development of new medical problems (7 subjects). In the remaining 182 subjects, sleepiness was noted within 1 month after what was judged appropriate treatment for SDB. In this group, the reason for persistent complaint was divided into four categories: 1) inappropriate treatment as a result of not using the measurement of esophageal pressure (Pes) in the initial diagnosis (41 subjects), 2) nonfunctional treatment (3 subjects), 3) associated narcolepsy-like syndrome (2 subjects), and 4) emergence of obesity and/or periodic leg movements as significant factors (135 subjects). The 135 subjects in this last category could be subdivided into three subgroups: 1) younger subjects, severely overweight with lower mean nocturnal saturated arterial oxygen (SaO2) values; 2) older subjects, of normal weight, with high numbers of periodic leg movements (PLM); and 3) moderately overweight subjects, with a combination of PLM and lower mean SaO2 values than expected. Treatments were aimed at eliminating the identified problems; they included standard medications for PLM and nasal bilevel positive airway pressure (BiPAP) for low SaO2 measurements. These treatments were not effective in specific cases, and stimulant medications had to be prescribed.

Utilization of health care services in patients with severe obstructive sleep apnea

We compared the health care utilization of 97 obese patients diagnosed with obstructive sleep apnea (OSA) and 97 matched control subjects. Over a 2-year period that ended 2 years prior to initial diagnosis, the OSA group had 251 nights in hospital, compared to 90 nights for the control group. During the same 2-year period, total expenditures from physician claims were $82,238 (Canadian dollars) in the OSA patients versus $41,018 in the control group (p < 0.01). Depending upon which assumptions one uses for the calculation of hospital costs, during the same 2-year period, the 97 OSA patients utilized between $100,000 and $200,000 more in services than their control counterparts. We conclude that sleep apnea patients are already heavy consumers of health care services prior to any specific evaluation and treatment for apnea.

[Ambulatory, comprehensive, behavior therapy-oriented weight reduction program (Optifast Program). An alternative therapy in obstructive sleep apnea]

We investigated the therapeutic effect of marked body weight reduction on the predominantly obstructive sleep apnea syndrome by the application of an out-patient, behaviour therapy based body weight reduction program (Optifast-program) in five of our obese apnea patients (mean overweight by Broca 53.6 +/- 24.8 kg). Mean body weight reduction was 32.7 +/- 15.8 kg after six months. The mean apnea-index of 34.5 +/- 23.1/h prior to the weight reduction dropped to 7.8 +/- 6.1/h after therapy. The mean apnea-hypopnea-index (so called "respiratory disturbance index", RDI) could be reduced from 45,7 +/- 26.0/h to 14.0 +/- 11.4/h. The best therapeutic effect on the sleep related respiratory parameters was seen in patients who reached their normal weight whereas the absolute weight reduction itself seems to be less important. Our results should encourage this causal therapy in appropriate patients.

Sleep disorders

Sleep disorders carry a high risk of morbidity and mortality, yet they receive little medical attention. This article outlines the clinical features, aetiology, diagnosis and management of some common sleep disorders.

[Amyotrophic lateral sclerosis and intermittent self ventilation therapy. Indications and follow-up]

BACKGROUND

Fully informed patients were willing to start with IPPV.

PATIENTS AND METHODS

Twenty-three patients with amyothropic lateral sclerosis (ALS) were treated with noninvasive intermittent mechanical ventilation (7 women, 16 men, mean age 59 years). The major symptoms were dyspnoe, heavy sleep disruption resulting in severely reduced quality of life.

RESULTS

Their symptoms improved. The blood gases normalized during spontaneous breathing. They remained stable, despite a rapid decrease in respiratory force. Thirteen patients died, 6 during an acute event, 4 during bronchopulmonary infection and 3 stopped therapy, when they were fully ventilator dependent.

CONCLUSION

We conclude that respiratory symptoms and quality of life can be improved by home intermittent mechanical ventilation. Indication should therefore be made earlier.

[Prevalence of sleep apnea syndrome with primary arterial hypertension in a cardiologic rehabilitation clinic]

In a group of 132 randomly selected male patients with the admission diagnosis arterial hypertension in a cardiological rehabilitation clinic, nightly monitoring was performed with Mesam 4 with records of the metabolism laboratory values and sleep disturbances longitudinally. Desaturation indexes of > or = 10/h after manual correction for plausibility revealed a total prevalence of 27.3% in the case of breathing disturbances. The prevalence increased to 52% in the over 55 year-old patients with a Broca index of > or = 120% in comparison to merely 15.4% in standard weighted, comparable age group. No differences were found in the laboratory values. These results again show the frequent occurrence of the combination adiposity, hypertension, and sleep apnea syndrome which has often been missed previously in specialist rehabilitation clinics.

[Incidence of obstructive sleep apnea syndrome in combination with chronic obstructive respiratory tract disease]

Polysomnographic measurements were performed in 210 indoor patients (age mean = 49.7 +/- 8.9 years, Broca mean = 126.0 +/- 20.7% FEV1%p mean = 79.9 +/- 23.9) of a pneumological rehabilitation centre who had a suspicious history or clinical symptoms of obstructive sleep apnoea. 72 had neither an airway obstruction nor a pathological apnoea index. 58 patients only suffered from airway obstruction and 42 had only a pathological apnoea index. In 38 patients, a pathological apnoea index and also airway obstructions were seen. For the last three groups we calculated the mean of the SaO2-values for an 8 hour night time period with and without n-CPAP-therapy. In both groups with only one disease a typical pattern of the SaO2-values during sleep could be demonstrated. The patients with overlap syndrome (SAS + COB) showed a superposition of both single disease SaO2-time courses even with much lower initial SaO2-values. During n-CPAP-therapy in all groups a reduction of the variations of SaO2 induced by sleep pattern and circadian rhythm are evident.

[Use of acoustic rhinometry for determining segmental airway geometry with nasal positive or negative pressure]

The investigations show an application of nasal acoustic rhinometry for determination of segmental naso- and oropharyngeal airway cross-section during negative or positive pressure breathing. The investigations show in 16 patients with obstructive sleep apnoea (AI = 21.5), that negative pressure produces a segmentally different reduction of naso-oropharyngeal cross-section which is weakly correlated to the Broca index. But the amount of cross-sectional reduction is highly significantly correlated to the apnoea index (r = 0.64). The functional relationship between pressure load of the airways during wakefulness and the severe nature of the disease reveals the possibility of diagnostic use.

Management of obstructive sleep apnoea

Obstructive sleep apnoea (OSA) is characterized by abnormal breathing during sleep, and occurs when the upper airway is obstructed but respiratory effort continues. Causes of OSA include obesity, overindulgence in alcohol, and the use of sedatives. The patient complains of unrefreshed sleep, morning headaches and drowsiness, sometimes leading to depression and intellectual impairment. The treatment of choice is weight loss; however, the patient may also require mechanical nocturnal support to prevent the upper airway collapsing and causing OSA. A simple and effective non-surgical treatment for OSA is nasal continuous positive airway pressure.

Sleep in postpolio syndrome

Post-polio patients may develop additional neuromuscular and respiratory symptoms decades after the acute attack, the post-polio syndrome. We hypothesize some post-polio symptoms may be due to breathing disorders occurring during sleep. We performed polysomnography on 13 post-polio patients: group 1 (five patients) were those already on ventilatory assistance (rocking beds) and group 2 (eight patients), those without any assistance. Patients requiring new treatment were then evaluated on nasal CPAP or nasal mask ventilation. Group 1 patients, on rocking beds, demonstrated consistently poor sleep quality with decreased total sleep time, sleep efficiency, percentage stage 2, slow wave sleep, rapid eye movement sleep and an increase in the number of arousals and percentage stage 1 sleep. Respiratory abnormalities were also present and in all cases caused significant O2 desaturation. These patients did not respond to CPAP with the rocking bed. Repeat night-time polysomnography on nasal mask ventilation demonstrated an improvement in sleep structure and gas exchange. Three group 2 patients, (group 2a) had sleep within normal limits. The five remaining (group 2b) had poor sleep quality that was similar to but not as disrupted as group 1 patients. All but one patient demonstrated obstructive or mixed apnea and were treated effectively with nasal CPAP. One patient required nasal mask ventilation (due to mixed apnea and marked hypoventilation) to which there was a dramatic response. These patients demonstrated improved sleep quality and an improvement in daytime symptomatology. Sleep studies should be performed on post-polio patients with excessive daytime sleepiness and respiratory complaints. Those with obstructive and mixed apnea can often be treated with nasal CPAP. Those with hypoventilation syndrome and sleep apnea attributable to sleepiness and respiratory complaints. Those with obstructive and mixed apnea can often be treated with nasal CPAP. Those with hypoventilation syndrome and sleep apnea attributable to respiratory muscle weakness can be treated with nasal mask ventilation. Individuals already on respiratory assistance such as rocking beds who have features of respiratory failure can also be treated effectively with long-term nasal mechanical ventilation.