Oral appliances for obstructive sleep apnoea

Multi-center safety and efficacy study of a negative-pressure intraoral device in obstructive sleep apnea

BACKGROUND

Intraoral devices, with or without negative oral pressure, can stabilize the oropharynx and reduce obstructive sleep apneas. We tested the hypothesis that treatment with the iNAP® Sleep Therapy System, which applies negative oral pressure through an intra-oral appliance, would reduce the severity of obstructive sleep apnea in a multi-center, prospective, first-night-randomized-order cross-over study.

METHODS/PATIENTS

130 patients fulfilled the entry criteria (age <75, AHI 15-55, BMI <33), and 63 entered the primary endpoint cohort (Total Sleep Time ≥4 h/night on the baseline polysomnogram and an oral negative vacuum time maintained by iNAP® ≥ 4 h/night and total sleep time ≥4 h/night during the first treatment study). 54 patients completed a second treatment sleep study at least 28 days after the first sleep study.

RESULTS

Among the primary endpoint cohort (n = 63, age = 53.2 ± 11.3, BMI = 27.1 ± 2.8), 33 patients (52 %; 95 % confidence interval = 40%-64 %, p < 0.001) responded to iNAP treatment according to the Sher criteria (>50 % reduction in AHI and an AHI ≤20 events/hr). The average oxy-hemoglobin saturation increased by 1-2%, and the average percent oxygen desaturation decreased (was less severe) by 1 % while using the iNAP device. The incidence of adverse events, all self-limited, was low. The reduction in the apnea-hypopnea index was durable over the 28-day study. Patients used iNAP on average 5.6 h per night during the study period.

CONCLUSION

The iNAP® Sleep Therapy System achieved a durable benefit in more than half the patients with moderate to severe obstructive sleep apnea and may be considered in patients who object to or failed continuous positive airway pressure.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02698059.

Brazilian Thoracic Association Consensus on Sleep-disordered Breathing

Sleep is essential for the proper functioning of all individuals. Sleep-disordered breathing can occur at any age and is a common reason for medical visits. The objective of this consensus is to update knowledge about the main causes of sleep-disordered breathing in adult and pediatric populations, with an emphasis on obstructive sleep apnea. Obstructive sleep apnea is an extremely prevalent but often underdiagnosed disease. It is often accompanied by comorbidities, notably cardiovascular, metabolic, and neurocognitive disorders, which have a significant impact on quality of life and mortality rates. Therefore, to create this consensus, the Sleep-Disordered Breathing Department of the Brazilian Thoracic Association brought together 14 experts with recognized, proven experience in sleep-disordered breathing.

Berlin and Epworth Surveys to Predict Obstructive Sleep Apnea for Adults on Biomimetic Oral Appliance Therapy: A Nonrandomized Clinical Trial

Background

Two questionnaires (Berlin Questionnaire (BQ) and Epworth Sleepiness Scale (ESS)) are the widely used screening instruments for subjects suffering from sleep disorders. Obstructive sleep apnea (OSA) is the most common form of sleep-disordered breathing. The biomimetic oral appliance therapy (BOAT) offers an alternative nonsurgical method, which can improve symptoms and indices of OSA on objective sleep testing.

Aim

To describe testing the ability of BQ and EES for prediction of BOAT outcomes during OSA.

Methods

Seventeen adults (9 males, 8 females; age, mean (SD): 45.76 (10.31), BMI mean (SD): 33.5(13.43)) who underwent an overnight sleep study were diagnosed by a sleep specialist physician. The BQ and EES were recorded before and after BOAT treatment. Subjects with mild-to-moderate OSA had 2 months of follow-up visits and underwent a final overnight sleep study to measure apnea-hypopnea index (AHI). The subjects were asked to wear the appliance for 10–12 hours/day and at night. Findings were analyzed statistically using paired t-tests.

Result

As per sleep test results, pre-BOAT AHI measures versus post-BOAT AHI measures showed significant improvement. Comparing the BQ before versus after treatment showed that at the pretreatment stage, 66.0% of patients had high-risk score, whereas 34% had low-risk score. After treatment, 66.0% of patient had low-risk scores, whereas 34% had high-risk scores. As for the ESS, treatment resulted in significant reduction of total score from 10.43 ± 6.32 to 5.00 ± 5.20 (P < 0.01, paired t-test). Finally, there was a mild negative correlation between AHI and each of the BQ and ESS scores that was not statistically significant (r = −0.420, N = 26, P > 0.05, and r = −0.41, N = 26, P > 0.05, respectively).

Conclusion

The BOAT device may provide a useful form of therapy to improve OSA-related PSG parameters such as AHI. Both BQ and ESS were predictive to improvements detected by the sleep study during BOAT device use.

Factors influencing adherence to oral appliance therapy in adults with obstructive sleep apnea: a systematic review and meta-analysis

STUDY OBJECTIVES

The review aimed to identify the factors influencing adherence to oral appliance therapy in adults with obstructive sleep apnea.

METHODS

The protocol was initially registered with the International Register of Systematic Reviews (Prospero: CRD42019122615) prior to undertaking a comprehensive electronic search of databases and references without language and date restrictions. Quality assessment was undertaken using the Cochrane Collaboration's risk of bias tool and Quality in Prognosis Studies (QUIPS) tool.

RESULTS

Studies exhibited low or unclear risk of bias for the domains assessed by the respective quality assessment tools. The influence of independent variables such as disease characteristics, patient characteristics, appliance features, and psychological and social factors on adherence levels was also assessed. There was a total of 31 included studies, which consisted of 8 randomized controlled trials, 2 controlled clinical trial, 7 prospective cohorts, 11 retrospective cohorts, and the remaining 3 studies were a case-series, case-control, and a mixed-methods. All 31 included studies were subject to qualitative analysis, with only 4 studies included in the quantitative analysis. Results of the meta-analysis demonstrated increased adherence with custom-made appliances, with a pooled mean difference of -1.34 (-2.02 to -0.66) and low levels of heterogeneity (I² = 0%).

CONCLUSIONS

A weak relationship was observed between objective adherence and patient and disease characteristics, such as age, sex, obesity, apnea-hypopnea index, and daytime sleepiness, to oral appliance therapy. Nonadherent patients reported more side effects with oral appliance therapy than users and tended to discontinue the treatment within the first 3 months. Custom-made oral appliances were preferred and increased adherence reported in comparison to ready-made appliances. Further research is imperative to examine the relationship between psychosocial factors and adherence to oral appliance therapy.

Clinical Evidence in the Treatment of Obstructive Sleep Apnoea with Oral Appliances: A Systematic Review

Background

Recent clinical guidelines have extended indications for oral appliances to subjects affected by moderate-to-severe obstructive sleep apnoea (OSA). The aim of this systematic review covering this important issue for public health is twofold: updating and summarizing the best available scientific evidence by selecting RCTs of quality only, and identifying the therapeutic pathways that can be transferred to the current clinical practice.

Methods

All the abstracts which were published before February 18, 2019, have been identified in three electronic databases (PubMed, Web of Science, and Cochrane). The Cochrane Collaboration's tool for assessing risk of bias was used as an assessment tool in order to evaluate the quality of the selected studies.

Results

The search strategy yielded 2,260 studies. After removing duplicates and studies that did not comply with the inclusion criteria, 32 full-text articles were assessed for eligibility, and 17 RCTs were finally included in the qualitative synthesis. The 17 selected studies were very heterogeneous in the type of included RCTs in terms of patient inclusion criteria, sample size, distribution of the two genders in the various groups, duration of treatment, and definition of primary and secondary outcomes, without any restriction on the definition of the control group. A common finding was the positive responsiveness of oral appliance treatment in subjects affected by mild-to-moderate OSA with some evidence for cases of severe OSA.

Conclusion

Higher-quality studies are needed in order to provide additional useful guidelines for dental clinicians for OSA management.

Effects of oral appliance treatment on inflammatory biomarkers in obstructive sleep apnea: A randomised controlled trial

Obstructive sleep apnea (OSA) may lead to increased circulating concentrations of inflammatory biomarkers and treatment may change these. We aimed to assess the effect of oral appliance (OA) therapy on inflammatory biomarkers in a randomised controlled pilot trial. A total of 71 patients with OSA and systemic hypertension were randomly allocated to an active, mandible protruded (OAa) or a passive, mandible non‐protruded device (OAp) treatment. Serum concentrations of the inflammatory biomarkers white blood cells, high‐sensitivity C‐reactive protein, interleukin 6, interleukin 10, and tumour necrosis factor‐α were measured at baseline and after 3 months of OA treatment. The differences between treatment groups in biomarker concentration change during the treatment were presented as the Vargha and Delaney effect size and evaluated with the Wilcoxon–Mann–Whitney test. This effect size expresses the probability of a higher value in a random participant from one group compared with a random patient from the other group, and a value of 0.5 means stochastically equal groups. After 3 months of treatment, there was a significant reduction of the apnea–hypopnea index in the OAa group compared with the OAp group (effect size 0.258, 95% confidence interval 0.146–0.386, p < .001). There were no significant differences between the groups in any of the inflammatory markers’ concentration changes during the treatment period (effect sizes between 0.488 and 0.524; all p values ≥.737). Thus, OA treatment for 3 months did not affect circulating concentrations of some common inflammatory markers in patients with OSA and systemic hypertension.

Mandibular Advancement Devices for OSA: An Alternative to CPAP?

Obstructive sleep apnea (OSA) is a prevalent condition causing unrefreshing sleep and excessive daytime sleepiness. It has individual socioeconomic impacts and, through association with increased risk of road traffic accidents, diabetes, and cardiovascular disease, OSA is a public health issue. Continuous positive airway pressure (CPAP) is the first-line treatment for moderate-to-severe OSA. It is effective in improving excessive daytime sleepiness and quality of life. There is also evidence that CPAP therapy has cardiovascular benefits although nature and extent remain uncertain. Despite its benefits, a significant proportion of patients are unable to tolerate CPAP. There are also patients with mild but symptomatic disease, for whom CPAP is usually not available or appropriate, so there is a need for other treatment options. Mandibular advancement devices (MADs) offer an effective alternative to CPAP and can improve daytime symptoms and quality of life. There are many devices available, representing a range of complexity and cost. It is challenging to properly evaluate the effectiveness of this ever-evolving range. The more basic MADs are cheaper and more accessible but are less well tolerated. More complex devices are better tolerated and may be more effective. However, they are more expensive and often require dental expertise, so access is more limited. Efforts continue to try to improve accessibility to effective MAD therapy. Alongside increasing awareness, this may be facilitated by developing and refining devices that could be fitted by non-dental clinicians, and potentially by patients themselves. Research efforts need to focus on determining how to efficiently identify patients who are likely to respond to MAD therapy, so as to improve clinical and cost-effectiveness of OSA therapy overall.

Heart rate variability in adults with obstructive sleep apnea: a systematic review

Obstructive Sleep Apnea is a common respiratory disorder characterized by recurrent nocturnal episodes of normal breathing interruption due to upper airway total or partial collapse. Obstructive sleep apnea and cardiovascular diseases has similar risk factors, but the first is also a predisposing factor for cardiovascular pathologies independently of individuals demographic characteristics or risk markers. Heart rate variability is a non-invasive method to evaluate the regulation of autonomic nervous system and its a promising marker for health and disease, such as cardiovascular and respiratory diseases. The aim was to review whether heart rate variability is altered in patients with obstructive sleep apnea. We searched in five databases, including BIREME, Cochrane, Scholar Google, MEDLINE/PubMed and Periodics CAPES, and reference lists were also searched. Only cross-sectional studies comparing the heart rate variability of obstructive sleep patients with controls were included. Two authors independently extracted data and assessed trial quality. Twelve studies (513 participants with obstructive sleep apnea and 340 controls) met the inclusion criteria. This review evidence that adults with obstructive sleep apnea may demonstrate diminished vagal tone and higher sympathetic responsiveness.

Durability of treatment effects of the Sleep Position Trainer versus oral appliance therapy in positional OSA: 12-month follow-up of a randomized controlled trial

PURPOSE

The Sleep Position Trainer (SPT) is a new option for treating patients with positional obstructive sleep apnea (POSA). This study investigated long-term efficacy, adherence, and quality of life during use of the SPT device compared with oral appliance therapy (OAT) in patients with POSA.

METHODS

This prospective, multicenter trial randomized patients with mild to moderate POSA (apnea-hypopnea index [AHI] 5-30/h) to SPT or OAT. Polysomnography was performed at baseline and after 3 and 12 months' follow-up. The primary endpoint was OSA severity; adherence, quality of life, and adverse events were also assessed.

RESULTS

Ninety-nine patients were randomized and 58 completed the study (29 in each group). Median AHI in the SPT group decreased from 13.2/h at baseline to 7.1/h after 12 months (P < 0.001); corresponding values in the OAT group were 13.4/h and 5.0/h (P < 0.001), with no significant between-group difference (P = 1.000). Improvements throughout the study were maintained at 12 months. Long-term median adherence was also similar in the two treatment groups; the proportion of patients who used their device for ≥ 4 h for 5 days in a week was 100% in the SPT group and 97.0% in the OAT group (P = 0.598).

CONCLUSIONS

The efficacy of SPT therapy was maintained over 12 months and was comparable to that of OAT in patients with mild to moderate POSA. Adherence was relatively high, and similar in the two groups.

TRIAL REGISTRATION

www.clinicaltrials.gov (NCT02045576).

Papageorgiou S. Oral Interventions for Obstructive Sleep Apnea

BACKGROUND

The effectiveness of intraoral appliances (IOA), maxillary expansion (ME), and maxillomandibular advancement (MMA) in the treatment of children and adults with obstructive sleep apnea (OSA) has not yet been adequately assessed.

METHODS

An umbrella review was performed based on established guidelines for evidence-based medicine. Data synthesis was performed only from randomized controlled trials with Paule-Mandel random-effects meta-analyses / meta-regressions using mean differences (MDs) and 95% confidence intervals (CIs) and was followed by the qualitative evaluation of the meta-evidence.

RESULTS

29 systematic reviews were included, 7 of which provided quantitative data. IOA were effective in improving apnea hypopnea index (AHI) compared to both, placebo appliances (12 trials; 525 patients; MD = -11.70; 95% CI: [-15.38; -8.01]; p<0.001) and no treatment (1 trial; 24 patients; MD = -14.30; [-21.59; -7.01]; p<0.001). Only the former comparison was supported by robust meta-evidence. Effectiveness of IOA as measured by the Epworth Sleepiness Scale, on the other hand, was not supported by robust meta-evidence. No randomized or prospective controlled trials were found on the effectiveness of ME (conventional or surgically assisted) and MMA.

CONCLUSION

Intraoral appliances are effective in reducing AHI and their use is substantiated by robust evidence. There is no evidence from high-quality research to support treatment with ME (conventional or surgically assisted) or MMA in patients with OSA.

Quality Assessment of Systematic Reviews on the Efficacy of Oral Appliance Therapy for Adult and Pediatric Sleep-Disordered Breathing

STUDY OBJECTIVES

To assess the methodological quality of published systematic reviews (SRs) and meta-analyses (MAs) about the efficacy of oral appliances (OA) in the management of adult and pediatric sleep-disordered breathing (SDB).

METHODS

SRs/MAs that evaluated the efficacy of OA therapy on the treatment of SDB in human subjects of all age groups were sought. Multiple electronic databases were searched for articles published in any language from the database's inception until January 2016. Two reviewers independently selected and then assessed the methodological quality of the studies using the Assessment of Multiple Systematic Reviews (AMSTAR) measurement tool.

RESULTS

Thirteen reviews on adult SDB were included (2 SRs and 11 SRs with MAs). Of those, seven were medium quality and six were high quality. Only four reviews were included on pediatric SDB (3 SRs and 1 SR with MA). Three of these were of high quality and one was medium quality. The identified limitations in the included reviews were failing to reference the excluded studies or describe reasons for exclusion, lack of applying valid criteria to assess the quality of included studies, lack of publication bias assessment, and absence of conflicts of interest reporting.

CONCLUSIONS

Overall, SRs/MAs on OA therapy for adult and pediatric SDB were conducted with acceptable methodological quality. High AMSTAR scores should not be extrapolated as a proxy of the methodological quality of the included evidence. There is a need for more primary studies and then that information can be used to be synthesized through SRs on pediatric SDB.

Effects of treatment with oral appliance on 24-h blood pressure in patients with obstructive sleep apnea and hypertension: a randomized clinical trial

BACKGROUND

Continuous positive airway pressure treatment has been shown to lower blood pressure (BP) in patients with obstructive sleep apnea (OSA). The aims of the present pilot study were to evaluate the potential effects of oral appliance (OA) therapy on BP, to assess various outcome BP measures, and to inform sample size calculation.

METHODS

Seventy-two patients with OSA and hypertension were randomly assigned to intervention with either an OA with mandibular advancement (active group) or an OA without advancement (control group). Before and after 3 months of treatment, the patients underwent nocturnal somnographic registration and 24-h ambulatory BP monitoring.

RESULTS

Among the various BP measures, the largest trend toward effect of OA treatment was seen in 24-h mean systolic BP with a 1.8 mmHg stronger BP reduction in the active group compared with controls. A stronger trend toward effect was seen in a subgroup with baseline ambulatory daytime mean systolic BP >135/85 mmHg where the mean systolic BP fell, on average, 2.6 mmHg. Additional exclusion of patients with baseline apnea hypopnea index (AHI) ≤15 gave a significant reduction in mean systolic BP of 4.4 mmHg (P = 0.044) in the active group compared with controls.

CONCLUSIONS

In patients with OSA and hypertension, OA treatment had a modest trend toward effect on reducing BP. A stronger trend toward treatment effect was seen after excluding patients with normal baseline ambulatory BP. Additional exclusion of patients with baseline AHI ≤15 showed a significant treatment effect. Data to inform sample size for an adequately powered randomized study are provided.

The surgical treatment of sleep-related upper airway obstruction

BACKGROUND

Obstructive sleep apnea (OSA) is a very common disorder among adults: the prevalence of mild OSA is 20%, and that of moderate or severe OSA is 6% to 7%. Simple snoring is even more common. Conservative treatments such as nocturnal ventilation therapy and oral appliances are successful as long as the patient actually uses them, but they do not eliminate the underlying obstruction of the upper airway.

METHOD

The relevant literature up to 2008 on the surgical treatment of OSA was selectively reviewed.

RESULTS

Five types of surgical treatment for OSA are available, each for its own indications: optimization of the nasal airway to support nasal ventilation therapy, (adeno-)tonsillectomy as first-line treatment for OSA in children, minimally invasive surgery for simple snoring and mild OSA, invasive surgery as first- and second-line treatment for mild OSA, and invasive multilevel surgery as second-line treatment of moderate to severe OSA that remains refractory to ventilation therapy.

CONCLUSION

Surgical treatment for OSA is appropriate for specific indications as a complement to the established conservative treatment methods.

[Tongue fixation system for therapy of sleeping disorders. A feasibility study]

INTRODUCTION

Forward displacement of the tongue is a verified principle in the therapy of sleep disorders which prevents the tongue from sinking backwards thus avoiding obstruction of the upper respiratory tract during sleep. In this feasibility study a novel oral appliance which connects to a pin implanted within the tongue was investigated.

METHODS

A new tongue positioning system using previously implanted tongue piercings as a pivot was developed. By pulling the tongue forward the oral device prevents airway obstruction. In our study we fitted 10 subjects who already had the tongue pierced with the developed oral device. The subjects underwent two nights of polysomnography with and without using the tongue positioning system. Wearing comfort and side effects were evaluated using a questionnaire. Moderate alcohol consumption was used to provoke snoring or apnea in the subjects. Tongue positioning with and without the device was visualized with oropharyngeal MRI.

RESULTS

Subjects did not report any discomfort or side effects wearing the device. Subjects showed only moderate snoring or apnea after alcohol consumption and snoring after alcohol consumption was reduced with the device. The average apnea/hypopnea index (AHI) was 0.8/h without the device. Using the device led to an increase of apnea in the subjects. MRI visualization showed that the device did not keep the upper airway space opened by fixing the tongue.

CONCLUSION

The effectiveness of the tongue positioning system should be improved by a modification which should be investigated in patients with preexisting sleep disorders.

[Guideline: Treatment of obstructive sleep apnea in adults]

The current guideline discusses conservative and surgical therapy of obstructive sleep apnea (OSA) in adults from the perspective of the ear, nose and throat specialist. The revised guideline was commissioned by the German Society of Ear-Nose-Throat, Head-Neck Surgery (DG HNO KHC) and compiled by the DG HNO KHC's Working Group on Sleep Medicine. The guideline was based on a formal consensus procedure according to the guidelines set out by the German Association of Scientific Medical Societies (AWMF) in the form of a"S2e guideline". Research of the literature available on the subject up to and including December 2008 forms the basis for the recommendations. Evaluation of the publications found was made according to the recommendations of the Oxford Centre for Evidence-Based Medicine (OCEBM). This yielded a recommendation grade, whereby grade A represents highly evidence-based studies and grade D those with a low evidence base.

Position paper on the use of mandibular advancement devices in adults with sleep-related breathing disorders. A position paper of the German Society of Dental Sleep Medicine (Deutsche Gesellschaft Zahnaerztliche Schlafmedizin, DGZS)

Custom-made mandibular advancement devices are an effective treatment option for snoring, upper airway resistance syndrome, and obstructive sleep apnea (OSA). Evidence-based data indicates their efficacy, and international sleep societies recommend oral appliance (OA) therapy for patients with sleep-related breathing disorders. The following position paper by the German Society of Dental Sleep Medicine (DGZS) is to guide the interdisciplinary team (sleep physician and sleep disorder dentist) in detail when to prescribe oral appliances. This position paper supports the responsible use of OA as an effective treatment option for patients with sleep-related breathing disorders. The paper advises of proper indication regarding OSA severity, body mass index (BMI), and dentition. It emphasizes the interdisciplinary approach of oral appliance therapy and suggests treatment under the guidance of dentists trained in dental sleep medicine.

The effects of 1-year treatment with a herbst mandibular advancement splint on obstructive sleep apnea, oxidative stress, and endothelial function

BACKGROUND

Obstructive sleep apnea (OSA) is associated with endothelial dysfunction. In the current study, we assessed the effect of long-term modified Herbst mandibular advancement splint (MAS) treatment on OSA, oxidative stress markers, and on endothelial function (EF).

METHODS

A total of 16 subjects participated (11 men and 5 women; mean [+/- SD] age, 54.0 +/- 8.3 years; mean body mass index, 28.0 +/- 3.1 kg/m(2)), 12 of whom completed the 1-year evaluation. Apnea severity, levels of oxidative stress markers, and EF were assessed after 3 months and 1 year of receiving treatment. For comparison, 6 untreated patients underwent two evaluations 9 months apart, and 10 non-OSA individuals were assessed once as a reference group. The results are presented as the mean +/- SD.

RESULTS

The mean apnea-hypopnea index (AHI) decreased significantly from 29.7 +/- 18.5 events/h before treatment to 17.7 +/- 11.1 events/h after 3 months of treatment and 19.6 +/- 11.5 events/h after 1 year of treatment (p < 0.005 for both). The mean Epworth sleepiness scale score decreased significantly from 12.4 +/- 6.0 before treatment to 10.2 +/- 6.6 after 3 months of treatment and 7.8 +/- 3.8 after 1 year of treatment (p < 0.001 for both). The mean EF improved significantly from 1.77 +/- 0.4 before treatment to 2.1 +/- 0.4 after 3 months of treatment (p < 0.05) and 2.0 +/- 0.3 after 1 year of treatment (p = 0.055), which were similar to the values of the reference group. Thiobarbituric acid-reactive substance (TBARS) levels decreased from 18.8 +/- 6.2 nmol malondialdehyde (MDA)/mL before treatment to 15.8 +/- 3.9 MDA/mL after 3 months of treatment (p = 0.09) and 15.5 +/- 3.2 nmol MDA/mL after 1 year of treatment (p < 0.05). There was a correlation between the improvement in AHI and in EF or TBARS levels (r = 0.55; p = 0.05). The untreated control group remained unchanged.

CONCLUSIONS

The Herbst MAS may be a moderately effective long-term treatment for patients with OSA. EF improved to levels that were not significantly different than reference levels, even though apneic events were not completely eliminated. We think that these data are encouraging and that they justify the performance of larger randomized controlled studies.

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.

Health-related quality of life in patients with sleep-disordered breathing: effect of mandibular advancement appliances

STATEMENT OF PROBLEM

Mandibular advancement appliances (MAAs) are increasingly being recognized in the management of sleep-disordered breathing (SDB). However, there is little available evidence regarding their impact on health-related quality of life.

PURPOSE

A prospective, nonrandomized controlled clinical trial was undertaken to evaluate the effect of MAA treatment on the quality of life of patients with SDB.

MATERIAL AND METHODS

Two hundred fifteen consecutively referred patients for MAA therapy who had a diagnosis of SDB confirmed by overnight polysomnography were recruited for study. The test group (n=120) received a Herbst appliance, a removable appliance comprised of separate maxillary and mandibular complete occlusal coverage acrylic splints, connected by means of bilateral telescopic arms. Patients in the control group (n=95) remained untreated for 4 months. All patients completed the Medical Outcomes Study 36-Item Short-Form Health Survey at baseline (T1) and at follow-up (T2). Cross-tabulation was performed for each independent variable against the group (control versus test) to determine the number of subjects and the percentage showing improvement and the level of significance (alpha=.05). Data were dichotomized (improvement versus no improvement), analyzed by simple logistic regression analysis, and expressed as the odds ratio.

RESULTS

Eighty-three (87%) control and 107 (89%) test patients completed the study. No statistical differences were observed at baseline in any of the parameters relating to severity of SDB, demographic, anthropometric, or quality of life measures between the 2 groups. Significant differences were observed in relation to the energy/vitality (P=.001) and physical role limitation (P=.025) domains following 4 months of treatment with an MAA.

CONCLUSIONS

Mandibular advancement appliances have a significant effect on a limited number of health-related quality of life domains for patients with SDB.

Obstructive sleep apnea - management update

Obstructive sleep apnea (OSA) is a highly significant condition based both on the high prevalence in community and significant consequences. Obstructive sleep apnea syndrome (OSAS), OSA together with hypersomnolence, is seen in 4% of middle-aged men and 2% of middle-aged women. OSA is associated with impaired quality of life and increased risks of motor vehicle accidents, cardiovascular disease (including hypertension and coronary artery disease), and metabolic syndrome. There is some evidence for the use of conservative interventions such as weight loss and position modification. CPAP remains the mainstay of treatment in this condition with high-level evidence supporting its efficacy. Continuous positive airway pressure (CPAP) is an intrusive therapy, with long-term adherence rates of less than 70%. Dental appliances have been shown to be effective therapy in some subjects but are limited by the inability to predict treatment responders. Alternative treatments are discussed but there is little role for upper airway surgery (except in a select few experienced institutions) or pharmacological treatment. The current levels of evidence for the different treatment regimens are reviewed.

Drug therapy for obstructive sleep apnoea in adults

BACKGROUND

The treatment of choice for moderate to severe obstructive sleep apnoea (OSA) is continuous positive airways pressure (CPAP) via a mask during sleep. However this is not tolerated by all patients and its role in mild OSA is not proven. Drug therapy has been proposed as an alternative to CPAP in some patients with mild to moderate sleep apnoea and could be of value in patients intolerant of CPAP. A number of mechanisms have been proposed by which drugs could reduce the severity of OSA. These include an increase in tone in the upper airway dilator muscles, an increase in ventilatory drive, a reduction in the proportion of REM sleep, an increase in cholinergic tone during sleep, a reduction in airway resistance and a reduction in surface tension in the upper airway.

OBJECTIVES

To determine the efficacy of drug therapies in the treatment of sleep apnoea.

SEARCH STRATEGY

We carried out searches on the Cochrane Airways Group Specialised Register of trials. Searches were current as of July 2005.

SELECTION CRITERIA

Randomised, placebo controlled trials involving adult patients with confirmed OSA . We excluded trials if continuous positive airways pressure, mandibular devices or oxygen therapy were used. No restriction was placed upon publication language or trial duration.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed studies for inclusion, undertook data extraction according to pre-specified entry criteria, and quality assessment of studies. No response for further information was forthcoming from study authors. Results were expressed as mean differences and 95% Confidence Intervals (CI).

MAIN RESULTS

Twenty-six trials of 21 drugs, involving 394 participants contributed data to the review. Most of the studies were small and many trials had methodological limitations. Each of the studies states that the subjects had OSA but diagnostic criteria were not always explicit and it is possible that some patients with central apnoeas may have been recruited. Six drugs had some impact on OSA severity and two altered daytime symptoms. One study reported that apnoea hypopnea index (AHI) was lower following treatment with intranasal fluticasone compared with placebo (23.3 versus 30.3) in 24 participants with sleep apnoea and rhinitis. Subjective alertness in the daytime also improved. Physostigmine gave an AHI of 41 compared to 54 on placebo (10 participants) and in a similar study Mirtazipine 15 mg produced an AHI of 13 compared to 23.7 for placebo (10 participants). Topical nasal lubricant given twice overnight resulted in an AHI of 14 compared to 24 with placebo (10 participants). These three latter studies were of single night crossover design and so there are no data on the acceptability of these treatments or their effect on symptoms. Paroxetine was shown to reduce AHI to 23.3 compared to 30.3 for placebo, most of the 20 participants tolerated the treatment but there was no improvement in daytime symptoms. Acetazolamide also reduced the AHI (one crossover trial of nine patients, mean difference 24 (95% CI 4 to 44). However there was no symptomatic benefit from the drug and it was poorly tolerated in the long term. Protriptyline led to a symptomatic improvement (improved versus not improved) in two out of three crossover trials (13 participants, Peto Odds Ratio 29.2 (95% CI 2.8 to 301.1) but there was no change in the apnoea frequency. In one trial naltrexone did reduce AHI, but total sleep time favoured placebo. No significant beneficial effects were found for medroxy progesterone, clonidine, mibefradil, cilazapril, buspirone, aminophylline, theophylline doxapram, ondansetron or sabeluzole.

AUTHORS' CONCLUSIONS

There is insufficient evidence to recommend the use of drug therapy in the treatment of OSA. Small studies have reported positive effects of certain agents on short-term outcome. Certain agents have been shown to reduce the AHI in largely unselected populations with OSA by between 24 and 45%. For fluticasone, mirtazipine, physostigmine and nasal lubricant, studies of longer duration are required to establish whether this has an impact on daytime symptoms. Individual patients had more complete responses to particular drugs. It is likely that better matching of drugs to patients according to the dominant mechanism of their OSA will lead to better results and this also needs further study.

Oral appliances for obstructive sleep apnoea

BACKGROUND

Obstructive sleep apnoea-hypopnoea (OSAH) is a syndrome characterised by recurrent episodes of partial or complete upper airway obstruction during sleep that are usually terminated by an arousal. Nasal continuous positive airway pressure (CPAP) is the primary treatment for OSAH , but many patients are unable or unwilling to comply with this treatment. Oral appliances (OA) are an alternative treatment for OSAH.

OBJECTIVES

The objective was to review the effects of OA in the treatment of OSAH in adults.

SEARCH STRATEGY

We searched the Cochrane Airways Group Specialised Register. Searches were current as of June 2005. Reference lists of articles were also searched.

SELECTION CRITERIA

Randomised trials comparing OA with control or other treatments in adults with OSAH .

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data and assessed trial quality. Study authors were contacted for missing information.

MAIN RESULTS

Sixteen studies (745 participants) met the inclusion criteria. All the studies had some shortcomings, such as small sample size, under-reporting of methods and data, and lack of blinding. OA versus control appliances (six studies): OA reduced daytime sleepiness in two crossover trials (WMD -1.81;95%CI -2.72 to -0.90), and improved apnoea-hypopnoea index (AHI) (-10.78; 95% CI-15.53 to -6.03 parallel group data - five studies). OA versus CPAP (nine studies): OA were less effective than CPAP in reducing apnoea-hypopnoea index (parallel group studies: WMD 13 (95% CI 7.63 to 18.36), two trials; crossover studies: WMD 7.97; (95% CI 6.38 to 9.56, seven trials). However, no significant difference was observed on symptom scores. CPAP was more effective at improving minimum arterial oxygen saturation during sleep compared with OA. In two small crossover studies, participants preferred OA therapy to CPAP. OA versus corrective upper airway surgery (one study): Symptoms of daytime sleepiness were initially lower with surgery, but this difference disappeared at 12 months. AHI did not differ significantly initially, but did so after 12 months in favour of OA.

AUTHORS' CONCLUSIONS

There is increasing evidence suggesting that OA improves subjective sleepiness and sleep disordered breathing compared with a control. CPAP appears to be more effective in improving sleep disordered breathing than OA. The difference in symptomatic response between these two treatments is not significant, although it is not possible to exclude an effect in favour of either therapy. Until there is more definitive evidence on the effectiveness of OA in relation to CPAP, with regard to symptoms and long-term complications, it would appear to be appropriate to recommend OA therapy to patients with mild symptomatic OSAH, and those patients who are unwilling or unable to tolerate CPAP therapy. Future research should recruit patients with more severe symptoms of sleepiness, to establish whether the response to therapy differs between subgroups in terms of quality of life, symptoms and persistence with usage. Long-term data on cardiovascular health are required.

Intranasal steroids and oral leukotriene modifier therapy in residual sleep-disordered breathing after tonsillectomy and adenoidectomy in children

OBJECTIVE

Tonsillectomy and adenoidectomy (T&A) is the primary therapeutic approach for sleep-disordered breathing (SDB) in children. However, residual mild SDB will be found in more than one third of these patients after T&A. We hypothesized that combined therapy with the leukotriene receptor antagonist montelukast and intranasal budesonide would result in normalization of residual SDB after T&A.

METHODS

During the period of October 2002 to February 2005, children who underwent T&A for SDB underwent a routine postoperative (second) overnight polysomnographic evaluation (PSG) 10 to 14 weeks after T&A surgery. In children with residual apnea hypopnea index (AHI) >1 and <5/hour of total sleep time (TST), treatment with montelukast and intranasal budesonide aqueous solution was administered for a period of 12 weeks (M/B group), at which time a third PSG was performed. Children who had residual SDB and did not receive M/B therapy from their treating physicians were recruited as control subjects.

RESULTS

Twenty-two children received M/B, and 14 children served as control subjects. Mean age, gender distribution, ethnicity, and BMI were similar in the 2 treatment groups. The mean AHI at the second PSG was 3.9 +/- 1.2/hour of TST and 3.6 +/- 1.4/hour of TST in M/B-treated and control patients, respectively. Similar nadir arterial oxygen saturation (87.3 +/- 1.2%) and respiratory arousal index (4.6 +/- 0.7/hour of TST) were recorded for both groups. However, the M/B group demonstrated significant improvements in AHI (0.3 +/- 0.3/hour of TST), in nadir arterial oxygen saturation (92.5 +/- 3.0%), and in respiratory arousal index (0.8 +/- 0.7/hour of TST) on the third PSG, whereas no significant changes occurred over time in control subjects.

CONCLUSIONS

Combined anti-inflammatory therapy that consists of oral montelukast and intranasal budesonide effectively improves and/or normalizes respiratory and sleep disturbances in children with residual SDB after T&A.

Obstructive sleep apnea in children

Despite increasing recognition of childhood obstructive sleep apnea syndrome (OSAS) as a significant public health problem, treatment of the condition remains inconsistent. Some children are screened using polysomnography and treated only when objective respiratory disturbances are identified. Many others receive adenotonsillectomy based only on signs and symptoms of upper airway obstruction without ever having a formal sleep study. Outcome-based data regarding the effectiveness of adenotonsillectomy, continuous positive airway pressure, and other treatments for childhood OSAS remain extremely limited. In this article, the major therapeutic options for treatment of childhood OSAS are reviewed. Adenotonsillectomy remains the most frequently used treatment for uncomplicated OSAS in children, but residual airway obstruction persists in a notable minority of patients. Nasal continuous positive airway pressure is used for children who are not good surgical candidates or who have failed previous surgical treatment, but is sometimes not tolerated by young children or their parents. Various alternative treatments are used on an individualized basis for children who cannot use the two first-line therapies for sleep apnea.

Treatment of sleep disorders in elderly patients

Sleep disorders are common among the elderly and are associated with diminished quality of life, increased risk for development of psychiatric disorders, inappropriate use of sleep aids, and decreased daytime functioning. The most common and important sleep disorders in the elderly include insomnia, obstructive sleep apnea syndrome, restless legs syndrome, rapid eye movement sleep behavior disorder, and the advanced sleep phase syndrome. In this article, we summarize the current treatment strategies for each of these sleep-related disorders. Before contemplating specific treatments, the authors recommend that more conservative and nonpharmacologic therapies be attempted first because the elderly are more likely to have medication side effects or complications related to surgery. Many sleep problems can be treated by simple sleep hygiene modifications that can be implemented and adopted easily. For others, therapies that specifically consider older adults may be required. For each of the sleep disorders we provide an updated discussion of therapies beginning with diet and lifestyle, pharmacologic treatment, interventional procedures, surgery, assistive devices, physical and speech therapy, exercise, and emerging therapies with specific considerations for older adults.

Quantification of Pharyngeal Patency in Patients with Sleep-Disordered Breathing

Many techniques are available for the assessment of pharyngeal characteristics in sleep-disordered breathing (SDB). However, most of the reported techniques are invasive to some extent and/or hard to perform during sleep studies. The focus of this concept paper is on the forced oscillation technique (FOT) to quantify pharyngeal patency in patients with SDB. In a pilot study, the potential of FOT for non-invasive and continuous assessment of pharyngeal patency during different types of respiratory events was studied in 8 patients with an established diagnosis of a sleep apnea-hypopnea syndrome. During polysomnography, FOT was applied using a 5-Hz pressure oscillation signal. The respiratory impedance was determined and considered as a marker for pharyngeal patency. The results demonstrate that FOT allows detection of the complete pharyngeal occlusion during obstructive sleep apnea. In addition, we found that central sleep apnea can be associated with pharyngeal closure. We also demonstrated that during the flow-limited breath preceding obstructive apnea, almost complete upper airway closure can occur during either the expiratory or the inspiratory phase. FOT is a suitable method to assess pharyngeal patency continuously and non-invasively during sleep. Furthermore, this technique has the potential to contribute substantially to our knowledge of upper airway physiology in SDB.

Clinical audit of subjects with snoring & sleep apnoea/hypopnoea syndrome fitted with mandibular repositioning splint

Snoring and obstructive sleep apnoea/hypopnoea syndrome (OSAHS) are often treated with mandibular repositioning splints (MRS), but the efficacy and satisfaction of them has not been comprehensively addressed. A survey on the use of and satisfaction with MRS was posted to 177 patients referred by a hospital orthodontic department for custom-fitting of a MRS. Data were analysed using non-parametric techniques. The response rate was 81% (n=144). Responders (30F, 114M) had mean (SD) age of 51 (11) years, apnoea+hypopnoea index (AHI) of 24 (21) per hr and Epworth Score of 10 (5) at diagnosis, and had been supplied with their MRS a median 7 (IQR 5-11) months previously. Fifty of the 144 patients (35%) had been offered continuous positive airway pressure (CPAP) treatment but had declined or abandoned this. Self-reported MRS use was 5 (2) h/night, with 74 of the 144 patients (51%) continuing to use MRS at least occasionally at a median 7 months after fitting. Survival analysis showed 12% still using MRS at 12 months. Epworth score fell slightly with MRS therapy [-2.4 (3.5); P=0.005] and 7 daytime and 2 nocturnal symptoms improved in MRS users (all P<0.05). Marital satisfaction did not change with MRS. Problems preventing MRS use in 70 non-users included: non-retention (n=12), sore mouth (n=13) or jaw (n=7), difficulties falling asleep (n=10) or breathing (n=7), excessive salivation (n=4), dental damage (n=4) and other problems (n=3). Continued use of MRS therapy was associated with a higher number of teeth, low marital satisfaction perceived by partners and greater improvement in symptoms reported by patients and partners. Continuance with MRS may be low and linked to tolerance problems.

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.