Nasal continuous positive airway pressure (nCPAP) treatment for obstructive sleep apnea, road traffic accidents and driving simulator performance: a meta-analysis

Risk of Motor Vehicle Accidents in Obstructive Sleep Apnea: Comparative Analysis of CPAP Versus Surgery

OBJECTIVE

To compare the incidence of motor vehicle accidents (MVAs) among patients with obstructive sleep apnea (OSA) undergoing continuous positive airway pressure (CPAP) therapy and sleep surgery.

STUDY DESIGN

Retrospective cohort study using the TriNetX national clinical database.

SETTING

Analysis of a nationwide patient cohort.

METHODS

The database was queried for patients with OSA (International Classification of Diseases, 10th Revision: G47.33) treated with CPAP (Current Procedural Terminology [CPT]: 94660), sleep surgery (CPT: 42145, 64568, 64582), or no treatment. Sleep surgeries included uvulopalatopharyngoplasty and hypoglossal nerve stimulation. 1:1 Propensity score matching (PSM) ensured cohort comparability by age, sex, and race. MVA incidence rates were analyzed, along with a subanalysis of OSA-related comorbidities as a surrogate of OSA severity.

RESULTS

A total of 2,832,437 patients with OSA were identified. Patients with OSA undergoing sleep surgery demonstrated a significantly lower incidence of MVAs (3.403%) compared to the OSA + CPAP cohort (6.072%) and the no-treatment group (4.662%). The odds ratio (OR) for MVA incidence in the no-treatment group compared to the OSA + sleep surgery cohort was 1.214 (95% confidence interval [CI]: 1.060-1.391, P = .0051). The OR in the OSA + sleep surgery cohort compared to the CPAP cohort was 0.545 (95% CI: 0.480-0.618, P < .0001). Patients with OSA who experienced MVAs were more likely to have comorbidities such as hypertension, diabetes, and heart failure following the accident.

CONCLUSION

Sleep surgery significantly reduces the risk of MVAs in patients with OSA compared to CPAP and no treatment. In appropriate candidates, surgery should be considered to mitigate personal and public health risks associated with OSA.

Cost-effectiveness analysis of continuous positive airway pressure treatment for obstructive sleep apnea in Singapore from a health system perspective

This study assessed the cost-effectiveness of continuous positive airway pressure treatment for obstructive sleep apnea in Singapore from a health system perspective. The analysis evaluated a 5-year care pathway using a Markov model, considering per-patient costs of treatment, health system cost savings of obstructive sleep apnea and attributed conditions, the effectiveness measured in disability-adjusted life years with a discount rate of 3% and a weighted 5-year continuous positive airway pressure adherence of 74.1% from Singapore studies. Per-patient costs of treatment were from a large public hospital in Singapore. Efficacy of continuous positive airway pressure treatment, health system costs and disability-adjusted life years were obtained from literature; costs are in US dollars. We conducted probabilistic sensitivity analysis, one-way sensitivity analysis and what-if analysis. Based on a willingness-to-pay threshold of US $50,000 per disability-adjusted life year in USA, continuous positive airway pressure therapy was highly cost-effective, with an incremental cost-effectiveness ratio of $13,822 per disability-adjusted life year averted. Compared with the annual total costs of $856 for patients with continuous positive airway pressure treatment diagnosed by an inpatient sleep study, the total costs for those diagnosed by a home sleep test were $625, resulting in a remarkable 27% reduction per patient per year. One-way sensitivity analysis indicated that costs of treatment, effectiveness of continuous positive airway pressure treatment and adherence had a higher impact on the cost-effectiveness of continuous positive airway pressure therapy. The what-if analysis suggested that for continuous positive airway pressure treatment to be cost-effective, adherence rate should be at least 16.1%. These findings provide valuable insights for policymakers in making informed decisions on funding diagnosis and continuous positive airway pressure therapy within Singapore's healthcare system.

Cost-Utility Analysis of Continuous Positive Airway Pressure Therapy Compared With Usual Care for Obstructive Sleep Apnea in the Public Health System in Brazil

OBJECTIVES

This study aimed to conduct a cost-utility analysis of continuous positive airway pressure (CPAP) therapy compared with usual care as treatment of moderate to severe cases of obstructive sleep apnea (OSA) in Brazil, where decentralized policies of CPAP provision are in place.

METHODS

Markov cohort model comparing CPAP therapy with usual care, that is, no specific treatment for OSA, for moderate to severe cases was used. The payer perspective from the Unified Health System, Brazil, was adopted. Effectiveness parameters and costs related to health states were informed by literature review. Resource use related to CPAP therapy was defined by specialists and costs informed by recent purchase and leasing contracts. Incremental cost-effectiveness ratios were generated for purchase and leasing contracts to reflect current practices. A conservative willingness-to-pay threshold was set at 1 gross domestic product per capita per quality-adjusted life-year (QALY) (Brazilian reais [BRL] 40 712/QALY). Uncertainties were explored in deterministic and probabilistic sensitivity analyses.

RESULTS

Incremental cost-effectiveness ratio for the purchase modality was 8303 BRL/QALY and for leasing 45 192 BRL/QALY. Considering the adopted willingness-to-pay threshold, provision of CPAP by the purchase modality was considered cost-effective but not the leasing modality. The parameter related to the greatest uncertainty was the reduction in the risk of having a stroke attributable to CPAP. Probabilistic analysis confirmed the robustness of results.

CONCLUSIONS

CPAP therapy is a cost-effective alternative compared with usual care for moderate to severe OSA for the purchase modality. These results should help underpinning the decision making related to a uniform policy of CPAP provision across the country.

Comparing the Driving Skills of Adolescents with Obstructive Sleep Apnea to Healthy Controls: The Results of a Case-Controlled Observational Study

Auto crashes are a leading cause of death and injury among adolescents. Untreated obstructive sleep apnea (OSA) can cause sleepiness and inattention, which could negatively impact novice drivers, but OSA-related studies have focused on older drivers. This study used a driving simulator to examine whether licensed 16-19-year-old adolescents with OSA have diminished driving skills. Twenty-one adolescents with OSA and twenty-eight without OSA (both confirmed using polysomnography) completed two randomly ordered driving trials in a simulator (with induced distractions versus without). A mixed ANOVA examined the between-subjects effect of the OSA group, the within-subjects effect of the distraction condition, and the group-by-condition interaction effect on the ability to maintain lane position and the frequency of extended eye glances away from the roadway. T-tests were also used to examine group differences in reported sleepiness and inattention during daily life. The distraction task increased extended off-road glances and difficulties maintaining lane position (p < 0.001). However, adolescents with OSA did not display worse eye glance or lane position than controls and there were no significant group-by-condition interactions. Although the groups differed on polysomonographic features, there were also no significant differences in reported sleepiness or inattention. The distraction task negatively impacted both groups of adolescent drivers, but those with OSA did not fare differentially worse. Most adolescents in our study had mild OSA (median obstructive apnea-hypopnea index = 4.4), the most common form in the community. It remains possible that youth with more severe OSA would show increased driving impairment.

International Consensus Statement on Obstructive Sleep Apnea

BACKGROUND

Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).

METHODS

Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.

RESULTS

The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.

CONCLUSION

This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

Low Prevalence of HSV-1 and Helicobacter pylori in HNSCC and Chronic Tonsillitis Patients Compared to Healthy Individuals

Recent studies identified viral and bacterial factors, including HSV-1 and H. pylori, as possible factors associated with diseases such as chronic tonsillitis and cancers, including head and neck squamous cell carcinoma (HNSCC). We assessed the prevalence of HSV-1/2 and H. pylori in patients with HNSCC, chronic tonsillitis, and healthy individuals using PCR after DNA isolation. Associations were sought between the presence of HSV-1, H. pylori, and clinicopathological and demographic characteristics and stimulant use. HSV-1 and H. pylori were most frequently identified in controls (HSV-1: 12.5% and H. pylori: 6.3%). There were 7 (7.8%) and 8 (8.6%) patients with positive HSV-1 in HNSCC and chronic tonsillitis patients, respectively, while the prevalence of H. pylori was 0/90 (0%) and 3/93 (3.2%), respectively. More cases of HSV-1 were observed in older individuals in the control group. All positive HSV-1 cases in the HNSCC group were associated with advanced tumor stage (T3/T4). The prevalence of HSV-1 and H. pylori was highest in the controls compared to HNSCC and chronic tonsillitis patients, which indicates that the pathogens were not risk factors. However, since all positive HSV-1 cases in the HNSCC group were observed only in patients with advanced tumor stage, we suggested a possible link between HSV-1 and tumor progression. Further follow-up of the study groups is planned.

Work-Related Sleep Disorders: Causes and Impacts

Insufficient sleep syndrome, shift work disorder, and obstructive sleep apnea (OSA) not only significantly impact the health of affected individuals, but also pose a threat to public safety. This article describes the clinical manifestations and impact of these sleep disorders, particularly as they pertain to workers' health and those with safety-sensitive positions. Sleep deprivation, circadian rhythm disruptions, and excessive daytime sleepiness-hallmarks of insufficient sleep, shift work disorder, and OSA, respectively-all lead to a series of cognitive deficits and impaired concentration that affect workers in a wide variety of fields. We describe the health consequences of these disorders along with treatment strategies, with a focus on current regulatory standards and the under-recognition of OSA in commercial drivers. Given its large scale, there is a need for improved guidelines and regulations for the screening, diagnosis, treatment, and long-term follow-up of OSA in commercial motor vehicle drivers. Increased recognition of the ways in which these sleep disorders impact workers will pave the way for significant improvements in occupational health and safety.

Cost-utility and budget impact analysis of CPAP therapy compared to no treatment in the management of moderate to severe obstructive sleep apnea in Colombia from a third-party payer perspective

OBJECTIVES

To conduct cost-utility and budget impact analysis of providing Continuous Positive Airway Pressure (CPAP) therapy versus no treatment for moderate to severe obstructive sleep apnea (OSA) in Colombia from a third-party payer perspective.

METHODS

We used a Markov model to assess the cost-utility and budget impact analysis of CPAP in patients over 40 years old with moderate to severe OSA. Data on effectiveness and utility values were obtained from published literature. A discount rate of 5% was applied for outcomes and costs. ICER was calculated and compared against the threshold estimated for Colombia, which is 86% of the GDP per capita.

RESULTS

Over a lifetime horizon, the base case analysis showed the incremental cost per quality-adjusted life-years (QALYs) gained with CPAP therapy was COP$3,503,804 (USD$1,011 in 2020 prices). The budget impact analysis showed that the adoption of CPAP therapy in the target population would lead to a cumulative net budget impact of COP$411,722 million (USD$118,784,412 in, 2020 prices) over five years of time horizon.

CONCLUSIONS

CPAP was cost-effective compared to no-treatment in OSA. According to the budget impact analysis, adopting this technology would require a budget allocation that is partially offset by reduced number of strokes and traffic accident events.

Epidemiology, Physiology and Clinical Approach to Sleepiness at the Wheel in OSA Patients: A Narrative Review

Sleepiness at the wheel (SW) is recognized as an important factor contributing to road traffic accidents, since up to 30 percent of fatal accidents have been attributed to SW. Sleepiness-related motor vehicle accidents may occur both from falling asleep while driving and from behavior impairment attributable to sleepiness. SW can be caused by various sleep disorders but also by behavioral factors such as sleep deprivation, shift work and non-restorative sleep, as well as chronic disease or the treatment with drugs that negatively affect the level of vigilance. An association between obstructive sleep apnea (OSA) and motor vehicle accidents has been found, with an increasing risk in OSA patients up to sevenfold in comparison to the general population. Regular treatment with continuous positive airway pressure (CPAP) relieves excessive daytime sleepiness and reduces the crash risk. Open questions still remain about the physiological and clinical determinants of SW in OSA patients: the severity of OSA in terms of the frequency of respiratory events (apnea hypopnea index, AHI) or hypoxic load, the severity of daytime sleepiness, concomitant chronic sleep deprivation, comorbidities, the presence of depressive symptoms or chronic fatigue. Herein, we provide a review addressing the epidemiological, physiological and clinical aspects of SW, with a particular focus on the methods to recognize those patients at risk of SW.

Obstructive sleep apnea: transition from pathophysiology to an integrative disease model

Obstructive sleep apnea (OSA) is characterised by recurring episodes of upper airway obstruction during sleep and the fundamental abnormality reflects the inability of the upper airway dilating muscles to withstand the negative forces generated within the upper airway during inspiration. Factors that result in narrowing of the oropharynx such as abnormal craniofacial anatomy, soft tissue accumulation in the neck, and rostral fluid shift in the recumbent position increase the collapsing forces within the airway. The counteracting forces of upper airway dilating muscles, especially the genioglossus, are negatively influenced by sleep onset, inadequacy of the genioglossus responsiveness, ventilatory instability, especially post arousal, and loop gain. OSA is frequently associated with comorbidities that include metabolic, cardiovascular, renal, pulmonary, and neuropsychiatric, and there is growing evidence of bidirectional relationships between OSA and comorbidity, especially for heart failure, metabolic syndrome, and stroke. A detailed understanding of the complex pathophysiology of OSA encourages the development of therapies targeted at pathophysiological endotypes and facilitates a move towards precision medicine as a potential alternative to continuous positive airway pressure therapy in selected patients.

The invisible costs of obstructive sleep apnea (OSA): Systematic review and cost-of-illness analysis

BACKGROUND

Obstructive sleep apnea (OSA) is a risk factor for several diseases and is correlated with other non-medical consequences that increase the disease's clinical and economic burden. However, OSA's impact is highly underestimated, also due to substantial diagnosis gaps.

OBJECTIVE

This study aims at assessing the economic burden of OSA in the adult population in Italy by performing a cost-of-illness analysis with a societal perspective. In particular, we aimed at estimating the magnitude of the burden caused by conditions for which OSA is a proven risk factor.

METHODS

A systematic literature review on systematic reviews and meta-analyses, integrated by expert opinion, was performed to identify all clinical and non-clinical conditions significantly influenced by OSA. Using the Population Attributable Fraction methodology, a portion of their prevalence and costs was attributed to OSA. The total economic burden of OSA for the society was estimated by summing the costs of each condition influenced by the disease, the costs due to OSA's diagnosis and treatment and the economic value of quality of life lost due to OSA's undertreatment.

RESULTS

Twenty-six clinical (e.g., diabetes) and non-clinical (e.g., car accidents) conditions were found to be significantly influenced by OSA, contributing to an economic burden ranging from €10.7 to €32.0 billion/year in Italy. The cost of impaired quality of life due to OSA undertreatment is between €2.8 and €9.0 billion/year. These costs are substantially higher than those currently borne to diagnose and treat OSA (€234 million/year).

CONCLUSIONS

This study demonstrates that the economic burden due to OSA is substantial, also due to low diagnosis and treatment rates. Providing reliable estimates of the economic impact of OSA at a societal level may increase awareness of the disease burden and help to guide evidence-based policies and prioritisation for healthcare, ultimately ensuring appropriate diagnostic and therapeutic pathways for patients.

Sleep Apnea Syndrome (SAS) Clinical Practice Guidelines 2020

The prevalence of sleep disordered breathing (SDB) is reportedly very high. Among SDBs, the incidence of obstructive sleep apnea (OSA) is higher than previously believed, with patients having moderate-to-severe OSA accounting for approximately 20% of adult males and 10% of postmenopausal women not only in Western countries but also in Eastern countries, including Japan. Since 1998, when health insurance coverage became available, the number of patients using continuous positive airway pressure (CPAP) therapy for sleep apnea has increased sharply, with the number of patients about to exceed 500,000 in Japan. Although the "Guidelines for Diagnosis and Treatment of Sleep Apnea Syndrome (SAS) in Adults" was published in 2005, a new guideline was prepared in order to indicate the standard medical care based on the latest trends, as supervised by and in cooperation with the Japanese Respiratory Society and the "Survey and Research on Refractory Respiratory Diseases and Pulmonary Hypertension" Group, of Ministry of Health, Labor and Welfare and other related academic societies, including the Japanese Society of Sleep Research, in addition to referring to the previous guidelines. Because sleep apnea is an interdisciplinary field covering many areas, this guideline was prepared including 36 clinical questions (CQs). In the English version, therapies and managements for SAS, which were written from CQ16 to 36, were shown. The Japanese version was published in July 2020 and permitted as well as published as one of the Medical Information Network Distribution Service (Minds) clinical practice guidelines in Japan in July 2021.

Sleep Apnea Syndrome (SAS) Clinical Practice Guidelines 2020

The prevalence of sleep-disordered breathing (SDB) is reportedly very high. Among SDBs, the incidence of obstructive sleep apnea (OSA) is higher than previously believed, with patients having moderate-to-severe OSA accounting for approximately 20% of adult males and 10% of postmenopausal women not only in Western countries but also in Eastern countries, including Japan. Since 1998, when health insurance coverage became available, the number of patients using continuous positive airway pressure (CPAP) therapy for sleep apnea has increased sharply, with the number of patients about to exceed 500,000 in Japan. Although the "Guidelines for Diagnosis and Treatment of Sleep Apnea Syndrome (SAS) in Adults" was published in 2005, a new guideline was prepared to indicate the standard medical care based on the latest trends, as supervised by and in cooperation with the Japanese Respiratory Society and the "Survey and Research on Refractory Respiratory Diseases and Pulmonary Hypertension" Group, of Ministry of Health, Labor and Welfare and other related academic societies, including the Japanese Society of Sleep Research, in addition to referring to the previous guidelines. Since sleep apnea is an interdisciplinary field covering many areas, this guideline was prepared including 36 clinical questions (CQs). In the English version, therapies and managements for SAS, which were written from CQ16 to 36, were shown. The Japanese version was published in July 2020 and permitted as well as published as one of the Medical Information Network Distribution Service (Minds) clinical practice guidelines in Japan in July 2021.

The public health burden of obstructive sleep apnea

Obstructive sleep apnea (OSA) is the most common respiratory disorder of sleep. The vast majority (>80%) of adults with moderate to severe OSA remain undiagnosed. The economic costs associated with OSA are substantial for both the individual and society as a whole; expenses are likely to be underestimated given that the disease remains undiagnosed in such a large percentage of individuals. The economic burden of motor vehicle collisions related to OSA alone is significant; it is estimated that 810,000 collisions and 1400 fatalities from car crashes in the United States were attributable to sleep apnea in 2000. The many health consequences of OSA include daytime sleepiness, reduced quality of life, decreased learning skills, and importantly, neurocognitive impairments that include impaired episodic memory, executive function, attention and visuospatial cognitive functions. Untreated OSA leads to numerous medical problems such as cardiovascular diseases that can potentially increase healthcare utilization. Untreated patients with sleep apnea consume a disproportionate amount of healthcare resources, expenditures that decrease after treatment. The gold-standard management of OSA remains treatment with CPAP (Continuous Positive Airway Pressure), which is effective in eliminating sleep fragmentation and preserving nocturnal oxygenation, thereby improving daytime sleepiness and quality of life. However, its impacts in reversing neurocognitive function are still uncertain. A significant impediment to CPAP effectiveness is low adherence rates (ranges from 50% to 75%). It is commonly accepted that CPAP improves excessive drowsiness; hence meliorates attention, and accumulating data suggest that CPAP improves a variety of other outcomes such as the risk of motor vehicle crashes.

Sleepiness Behind the Wheel and the Implementation of European Driving Regulations

Sleep disturbance and sleepiness are established risk factors for driving accidents and obstructive sleep apnea (OSA) is the most prevalent medical disorder associated with excessive daytime sleepiness. Because effective treatment of OSA reduces accident risk, several jurisdictions have implemented regulations concerning the ability of patients with OSA to drive, unless effectively treated. This review provides a practical guide for clinicians who may be requested to certify a patient with OSA as fit to drive regarding the scope of the problem, the role of questionnaires and driving simulators to evaluate sleepiness, and the benefit of treatment on accident risk.

One-Year Adherence to Continuous Positive Airway Pressure With Telemonitoring in Sleep Apnea Hypopnea Syndrome: A Randomized Controlled Trial

Study Objective: Telemedicine (TM) for continuous positive airway pressure (CPAP) treated patients may save health-care resources without compromising treatment effectiveness. We assessed the effect of TM (AirView Online System, ResMed) during the CPAP habituation phase on 3-month and 1-year treatment adherence and efficacy in patients with moderate-to-severe obstructive sleep apnea (OSA).

Methods: At CPAP initiation, 120 patients diagnosed with OSA were randomized to either usual care (UC) or TM during the habituation phase (clinical registration: ISRCTN12865936). Both groups received a first face-to-face appointment with a sleep care giver at CPAP initiation. Within the following month, 2 other physical visits were scheduled in the UC group whereas two phone consultations were planned in the TM group, in which CPAP parameters were remotely adapted. Additional physical visits were programmed at the patient's request. Face-to-face consultations were scheduled at 3 and 12 months after CPAP initiation. The primary outcome was the mean CPAP daily use over the course of 12 months.

Results: Twenty of 60 patients stopped CPAP therapy in the UC group vs. 14 of 60 in the TM group (p = 0.24). In per protocol analysis, mean [95% CI] daily CPAP use among 86 patients still using CPAP at 12 months was 279 [237; 321] min in the 38 patients on UC and 279 [247; 311] min in the 43 patients on TM, mean difference [95% CI]: 0 [−52; 52] min, P = 0.99. Total consultation time per patient was not different between groups, TM: 163 [147; 178] min, UC: 178 [159; 197] min, difference: −15 [−39; 9] min, p = 0.22.

Conclusions: Telemedicine during the CPAP habituation phase did not alter daily CPAP use or treatment adherence and did not require more healthcare time. Telemedicine may support clinic attendance for CPAP titration.

Clinical Trial Registration: [ISRCTN], identifier [ISRCTN12865936].

Effects of surgery for obstructive sleep apnea on cognitive function and driving performance

BACKGROUND

Obstructive sleep apnea (OSA) is associated with a significantly increased risk of motor vehicle accidents in addition to such cognitive impairments as attention and memory deficits. The aim of the study was to examine the effect of upper airway surgery for OSA on driving and cognitive function.

METHODS

Adult patients who underwent surgery for OSA at a tertiary medical center in 2016-2019 were prospectively recruited. Patients were assessed before and 3-6 months after surgery with a self-report and neurocognitive battery and a driving simulation platform.

RESULTS

The cohort included 32 patients of average age 46.9 ± 11.6 years. During the 3 years before treatment, 9 patients had been involved in road accidents and 18 were detained by police for traffic violations. After surgery, there was a significant decrease in the Epworth Sleepiness Scale (13.7 vs. 8.1, p 0.043) and a significant reduction in time to completion of the Color Trail Test (part 1: 21.4 vs 18.7 s, p = 0.049; part 2: 46.8 vs 40.5 s, p = 0.038). Improvements in divided attention and selective attention response times were noted on the advanced stages of the Useful Field of Vision Scale (p = 0.013, p = 0.054). Before surgery, patients showed a high tendency to drive over the speed limit and to cross the dividing line to the opposite lane on the simulation test. Nevertheless, all considered themselves good drivers. These tendencies decreased after treatment.

CONCLUSIONS

Surgery for OSA can significantly improve driving performance and cognitive function.

European Respiratory Society statement on sleep apnoea, sleepiness and driving risk

Obstructive sleep apnoea (OSA) is highly prevalent and is a recognised risk factor for motor vehicle accidents (MVA). Effective treatment with continuous positive airway pressure has been associated with a normalisation of this increased accident risk. Thus, many jurisdictions have introduced regulations restricting the ability of OSA patients from driving until effectively treated. However, uncertainty prevails regarding the relative importance of OSA severity determined by the apnoea–hypopnoea frequency per hour and the degree of sleepiness in determining accident risk. Furthermore, the identification of subjects at risk of OSA and/or accident risk remains elusive. The introduction of official European regulations regarding fitness to drive prompted the European Respiratory Society to establish a task force to address the topic of sleep apnoea, sleepiness and driving with a view to providing an overview to clinicians involved in treating patients with the disorder. The present report evaluates the epidemiology of MVA in patients with OSA; the mechanisms involved in this association; the role of screening questionnaires, driving simulators and other techniques to evaluate sleepiness and/or impaired vigilance; the impact of treatment on MVA risk in affected drivers; and highlights the evidence gaps regarding the identification of OSA patients at risk of MVA.

The Drives for Driving Simulation: A Scientometric Analysis and a Selective Review of Reviews on Simulated Driving Research

Driving behaviors and fitness to drive have been assessed over time using different tools: standardized neuropsychological, on-road and driving simulation testing. Nowadays, the great variability of topics related to driving simulation has elicited a high number of reviews. The present work aims to perform a scientometric analysis on driving simulation reviews and to propose a selective review of reviews focusing on relevant aspects related to validity and fidelity. A scientometric analysis of driving simulation reviews published from 1988 to 2019 was conducted. Bibliographic data from 298 reviews were extracted from Scopus and WoS. Performance analysis was conducted to investigate most prolific Countries, Journals, Institutes and Authors. A cluster analysis on authors' keywords was performed to identify relevant associations between different research topics. Based on the reviews extracted from cluster analysis, a selective review of reviews was conducted to answer questions regarding validity, fidelity and critical issues. United States and Germany are the first two Countries for number of driving simulation reviews. United States is the leading Country with 5 Institutes in the top-ten. Top Authors wrote from 3 to 7 reviews each and belong to Institutes located in North America and Europe. Cluster analysis identified three clusters and eight keywords. The selective review of reviews showed a substantial agreement for supporting validity of driving simulation with respect to neuropsychological and on-road testing, while for fidelity with respect to real-world driving experience a blurred representation emerged. The most relevant critical issues were the a) lack of a common set of standards, b) phenomenon of simulation sickness, c) need for psychometric properties, lack of studies investigating d) predictive validity with respect to collision rates and e) ecological validity. Driving simulation represents a cross-cutting topic in scientific literature on driving, and there are several evidences for considering it as a valid alternative to neuropsychological and on-road testing. Further research efforts could be aimed at establishing a consensus statement for protocols assessing fitness to drive, in order to (a) use standardized systems, (b) compare systematically driving simulators with regard to their validity and fidelity, and (c) employ shared criteria for conducting studies in a given sub-topic.

Effect of Positive Airway Pressure Therapy on Drowsy Driving in a Large Clinic-Based Obstructive Sleep Apnea Cohort

STUDY OBJECTIVES

Drowsy driving related to obstructive sleep apnea (OSA) represents an important public health problem with limited data on the effect of positive airway pressure (PAP) therapy. We hypothesize that PAP therapy will reduce self-reported drowsy driving in a large clinic-based OSA cohort.

METHODS

Drowsy driving (self-reported near-accidents/accidents) incidents from baseline to after PAP therapy (stratified by adherence) were compared in a cohort of 2,059 patients with OSA who initiated PAP therapy from January 1, 2010 to December 31, 2014. Multivariable logistic regression models evaluated the dependence of change in drowsy driving incidents on other factors, including change in Epworth Sleepiness Scale (ESS) and Patient Health Questionnaire-9 (PHQ9) scores.

RESULTS

In the entire cohort (age 56.0 ± 13.1 years, 45.4% female, 76.0% white, average follow-up 124.4 ± 67.3 days), drowsy driving incidents reduced from 14.2 to 6.9% after PAP therapy (P < .001). In subgroups, drowsy driving incidents reduced from 14% to 5.3% (P < .001) in patients who self-reported adherence to PAP therapy and 14.1% to 5.3% (P < .001) in patients objectively adherent to PAP therapy. For each one-point improvement in Epworth Sleepiness Scale score, the odds of drowsy driving decreased by about 14% (odds ratio 0.86, 95% confidence interval 0.82 to 0.90).

CONCLUSIONS

In this clinic-based cohort, drowsy driving improved after adherent PAP usage, with greater drowsy driving risk for those with greater sleep propensity. This highlights the importance of and need for routine drowsy driving assessments and careful clinical attention to PAP adherence and sleep propensity in this population. Our findings should be confirmed and may be used to provide support for initiatives to address the public health issue of drowsy driving.

Assessment of Sleepiness in Drivers: Current Methodology and Future Possibilities

Many patients with obstructive sleep apnea syndrome (OSAS) drive a vehicle both for pleasure and as part of their employment. Some, but not all, patients with OSAS are at increased risk of being involved in road traffic accidents. Clinicians are often asked to make recommendations about an individual's fitness to drive, and these are likely to be inconsistent in the absence of objective criteria. This article discusses the current practice of the assessment of individuals' sleepiness with respect to driving, the limitations of available techniques, and future possibilities.

Sleepiness and Driving: Benefits of Treatment

Drowsy driving is common and causes 21% of fatal crashes. Individuals at risk include young men, shift workers, older adults, and people with chronic short sleep duration, untreated obstructive sleep apnea (OSA), and narcolepsy. Untreated OSA is a particular concern in commercial drivers, who are at higher risk for the disorder. Treatment for sleep problems such as sleep extension for chronic short sleep, positive airway pressure (PAP) for OSA, pharmacologic treatments, and drowsy driving countermeasures may reduce the risk of crashes. Implementing screening measures to identify common sleep problems contributing to drowsy driving continues to be of high importance.

Cost-effectiveness of continuous positive airway pressure therapy for obstructive sleep apnea: health care system and societal perspectives

Study Objectives

To determine cost-effectiveness of continuous positive airway pressure (CPAP) treatment of obstructive sleep apnea (OSA) in Australia for 2017–2018 to facilitate public health decision-making.

Methods

Analysis was undertaken of direct per-person costs of CPAP therapy (according to 5-year care pathways), health system and other costs of OSA and its comorbidities averted by CPAP treatment (5-year adherence rate 56.7%) and incremental benefit of therapy (in terms of disability-adjusted life years [DALYs] averted) to determine cost-effectiveness of CPAP. This was expressed as the incremental cost-effectiveness ratio (= dollars per DALY averted). Direct costs of CPAP were estimated from government reimbursements for services and advertised equipment costs. Costs averted were calculated from both the health care system perspective (health system costs only) and societal perspective (health system plus other financial costs including informal care, productivity losses, nonmedical accident costs, deadweight taxation and welfare losses). These estimates of costs (expressed in US dollars) and DALYs averted were based on our recent analyses of costs of untreated OSA.

Results

From the health care system perspective, estimated cost of CPAP therapy to treat OSA was $12 495 per DALY averted while from a societal perspective the effect was dominant (−$10 688 per DALY averted) meaning it costs more not to treat the problem than to treat it.

Conclusions

These estimates suggest substantial community investment in measures to more systematically identify and treat OSA is justified. Apart from potential health and well-being benefits, it is financially prudent to do so.

Effectiveness of nasal continuous airway pressure therapy in patients with obstructive sleep apnea

OBJECTIVES

A prospective observational study was carried out with the aim of evaluating the effectiveness of nasal continuous positive airway pressure (nCPAP) therapy on the health-related quality of life (QoL) of patients with obstructive sleep apnea (OSA).

METHODS

The patients included in this study were those recently diagnosed with OSA (AHI > 5) and given nCPAP therapy, as well as being referred to a sleep laboratory for an assessment of their sleep disordered breathing. Prior to the start of nCPAP therapy and polysomnography evaluation, patients were asked to complete the validated Quebec sleep questionnaire (QSQ), and their baseline measurements were recorded.

RESULTS

Among the study population, 14.41% (n = 31) had mild OSA with an apnea and hypopnea index of 5 to 14.9 events/h, while 26.97% (n = 58) had moderate OSA and 40% (n = 86) had severe OSA. The overall average apnea and hypopnea index of the study population was 30.24 ± 9.73 events/h; mild OSA patients had an average apnea and hypopnea index of 10.09 ± 2.65 events/h, moderate OSA patients had 21.48 ± 4.40 events/h, and severe OSA patients had 59.16 ± 22.14 events/h. A significant difference was observed between the scores before treatment and after 6 months of therapy in all domains of the QSQ QoL scores (P < 0.0001).

CONCLUSION

Nasal continuous positive airway pressure treatment improved the QoL for patients with mild, moderate, and severe sleep apnea.

Rhinological interventions for obstructive sleep apnoea - a systematic review and descriptive meta-analysis

OBJECTIVES

Obstructive sleep apnoea is a common chronic sleep disorder characterised by collapse of the upper airway during sleep. The nasal airway forms a significant part of the upper airway and any obstruction is thought to have an impact on obstructive sleep apnoea. A systematic review was performed to determine the role of rhinological surgical interventions in the management of obstructive sleep apnoea.

METHODS

A systematic review of current literature was undertaken; studies were included if they involved comparison of a non-surgical and/or non-rhinological surgical intervention with a rhinological surgical intervention for treatment of obstructive sleep apnoea.

RESULTS

Sixteen studies met the selection criteria. The pooled data suggest that there are reductions in the apnoea/hypopnea index and respiratory disturbance index following nasal surgery. However, the current body of studies is too heterogeneous for statistically significant meta-analysis to be conducted.

CONCLUSION

Nasal surgery may have limited benefit for a subset of patients based on current evidence.

Distance to Specialist Medical Care and Diagnosis of Obstructive Sleep Apnea in Rural Saskatchewan

Obstructive sleep apnea (OSA) is the most common sleep-disordered breathing condition. Patients with OSA symptoms are often not diagnosed clinically, which is a concern, given the health and safety risks associated with unmanaged OSA. The availability of fewer practicing medical specialists combined with longer travel distances to access health care services results in barriers to diagnosis and treatment in rural communities. This study aimed to (1) determine whether the proportion of adults reporting OSA symptoms in the absence of a sleep apnea diagnosis in rural populations varied by travel distance to specialist medical care and (2) assess whether any distance-related patterns were attributable to differences in the frequency of diagnosis among adults who likely required this specialist medical care. We used a cross-sectional epidemiologic study design, augmented by analysis of follow-up survey data. Our study base included adults who completed a 2010 baseline questionnaire for the Saskatchewan Rural Health Study. Follow-up occurred until 2015. 6525 adults from 3731 households constituted our sample. Statistical models used log-binomial regression. Rural adults who reported the largest travel distances (≥250 km) to specialist medical care were 1.17 (95% CI: 1.07, 1.29) times more likely to report OSA symptoms in the absence of a sleep apnea diagnosis than those who reported the smallest (<100 km; referent) distances. However, the proportion of sleep apnea diagnoses was low and unaffected by reported travel distance among adults who likely required this specialist medical care. Our findings suggest factors other than travel distance may be contributing to the low sleep apnea diagnostic rate. This remains important as undiagnosed and untreated OSA has serious implications on the health of people and populations, but effective treatments are available. Health care access barriers to the diagnosis and treatment of OSA require evaluation to inform health care planning and delivery.

Challenges and perspectives in obstructive sleep apnoea

Obstructive sleep apnoea (OSA) is a major challenge for physicians and healthcare systems throughout the world. The high prevalence and the impact on daily life of OSA oblige clinicians to offer effective and acceptable treatment options. However, recent evidence has raised questions about the benefits of positive airway pressure therapy in ameliorating comorbidities.

An international expert group considered the current state of knowledge based on the most relevant publications in the previous 5 years, discussed the current challenges in the field, and proposed topics for future research on epidemiology, phenotyping, underlying mechanisms, prognostic implications and optimal treatment of patients with OSA.

The group concluded that a revision to the diagnostic criteria for OSA is required to include factors that reflect different clinical and pathophysiological phenotypes and relevant comorbidities (e.g.nondipping nocturnal blood pressure). Furthermore, current severity thresholds require revision to reflect factors such as the disparity in the apnoea–hypopnoea index (AHI) between polysomnography and sleep studies that do not include sleep stage measurements, in addition to the poor correlation between AHI and daytime symptoms such as sleepiness. Management decisions should be linked to the underlying phenotype and consider outcomes beyond AHI.

Sleep apnea and its role in transportation safety

Obstructive sleep apnea (OSA) is a main cause of excessive daytime sleepiness and increases the risk for driving accidents, which can be normalized by treatment with continuous positive airway pressure ventilation. Since it is estimated that OSA is not diagnosed in about 80% of cases, recognition of patients at risk for driving accidents is a problem from both medical and societal points of view. Strategies to screen and identify subjects at high risk for driving accidents are under study in order to improve safety on the road, especially for commercial drivers, who show a high prevalence of OSA.

A 4-week wait 'fast-track' sleep service is effective at establishing vocational drivers on continuous positive airway pressure

We sought to establish whether an expedited or 'fast-track' NHS service to diagnose obstructive sleep apnoea (OSA) and establish vocational drivers on continuous positive airway pressure (CPAP) within 4 weeks of referral was possible. This model is recommended by the OSA Partnership Group. In total, 55 vocational drivers were referred to two sleep services. Assessment showed 73% had moderate or severe OSA on sleep study. Of those commenced on CPAP, review was a mean of 15 days after initiation (range 3-62 days). Median time from referral (or first clinic visit) to review on CPAP was 32 days, showing a 'fast-track' pathway is deliverable.

Comparison of titrable thermoplastic versus custom-made mandibular advancement device for the treatment of obstructive sleep apnoea

BACKGOUND AND OBJECTIVES

The disadvantages of custom-made mandibular advancement devices (MAD) for obstructive sleep apnoea (OSA) therapy are the cost and delay required to manufacture the device. This study aimed to evaluate the efficacy of a titrable, thermoplastic MAD compared to a custom-made MAD for OSA therapy.

METHODS

In this prospective nonrandomized study, 158 patients with OSA from two French sleep centers were treated for 6 months with a titrable thermoplastic MAD (n = 86) or a custom-made MAD (n = 72). The primary outcome was the change in sleep-disordered breathing (SDB) severity.

RESULTS

After adjustment for baseline values, age, body mass index and study site, no significant intergroup differences were observed between thermoplastic and custom-made MAD for the outcome of apnoea, hypopnoea and oxygen desaturation indices. No between treatment differences were observed for the outcome of subjective sleepiness, symptoms of snoring and fatigue, depressive symptoms, and quality of life. Thermoplastic MAD therapy was associated with higher side effects scores for tooth pain (p < 0.0001) and self-reported occlusal changes (p = 0.0069). Mean (SD) reported compliance was lower in the thermoplastic MAD group than in the custom-made MAD group (6.4 [0.2] vs 7.1 [0.1] h/night; p = 0.035).

CONCLUSIONS

This study demonstrates the efficacy of a titrable thermoplastic MAD in reducing SDB and related symptoms in patients with mild to severe OSA. Reported compliance at 6 months was high despite more dental discomfort than with custom-made MAD.

Continuous positive airway pressure therapy in obstuctive sleep apnea: benefits and alternatives

INTRODUCTION

Obstructive sleep apnea (OSA) is a highly prevalent condition affecting persons of all age with an increasing public health burden. It is implicated in cardiovascular disease, metabolic syndrome, neurocognitive impairment, reductions in quality of life, and increased motor vehicle accidents. The goals of OSA treatment are to improve sleep and daytime symptoms, and minimize cardiovascular risks.Areas covered: Continuous positive airway pressure (CPAP) is considered the gold standard therapy that delivers pressurized air into the upper airway to relieve obstruction during sleep. Although CPAP is an effective modality of treatment for OSA, adherence to therapy is highly variable. This article highlights the benefits of CPAP therapy, along with alternative treatment options including oral appliance, implantable and wearable devices, and surgery. Expert commentary: CPAP therapy is the gold standard treatment option and should continue to be offered to those who suffer from OSA. Alternative options are available for those who are unable to adhere to CPAP or choose an alternative treatment modality. The most interesting advances have been incorporating orthodontic procedures in conjunction with myofunctional therapy in prepubertal children, raising the possibility of OSA prevention by initiating treatment early in life.

Validation of the System One RemStar Auto A-Flex for Obstructive Sleep Apnea Treatment and Detection of Residual Apnea-Hypopnea Index: A European Randomized Trial

STUDY OBJECTIVES

Autotitrating continuous positive airway pressure (CPAP) devices adjust pressure in response to changes in airflow and are an alternative to attended in-laboratory titration polysomnography (PSG) to determine optimal pressure levels. The aim of this study was to compare the performance of the System One RemStar Auto A-Flex (Philips Respironics, Murrysville, PA, USA) automatically adjusted positive airway pressure (APAP) mode to manually titrated, fixed pressure CPAP and to validate the device's breathing event detection capabilities against attended in-laboratory PSG.

METHODS

Sixty-one patients investigated in five centers for moderate to severe obstructive sleep apnea between May 2012 and June 2013 were invited to participate. Participants underwent two full-night attended polysomnograms in random order with manually titrated, fixed pressure CPAP versus APAP.

RESULTS

Fifty-three participants with a mean apnea-hypopnea index (AHI) of 45.9 ± 23 completed two sleep studies and were included in the analysis. There were significant but not clinically relevant differences between APAP and CPAP respectively: Apnea index [1.0 (2.8 ± 0.8), median (mean ± standard deviation)] versus [1.8 (5.3 ± 11.5)], p = 0.004; percentage of N1 sleep [12.3 (15.9 ± 0.5)] versus [14.3 (18.9 ± 12.7)], p = 0.028. AHI values differed between PSG [2.8 (5.5. ± 9.3)] and device [3.7 (6.0 ± 8.6)], p = 0.003). Regarding residual events detection, intraclass correlation coefficients for AHI were strong (0.956, p < 0.001) and the area under the curve was 0.988 (AHI cut-off value of 10).

CONCLUSIONS

The new APAP modality was effective and residual apnea-hypopnea indices calculated by the device strongly correlated to those assessed by PSG.

COMMENTARY

A commentary on this article appears in this issue on page 167.

[Therapeutic alternatives to continuous positive airway pressure for obstructive sleep apnea-hypopnea syndrome]

Oral appliance therapy (OAT) is the main therapeutic alternative to continuous positive airway pressure (CPAP). OAT has been recommended as an appropriate first-line treatment option for moderate obstructive sleep apnea-hypopnea syndrome (OSAHS) in patients without severe cardiovascular comorbidity. The lower efficacy of OAT in reducing sleep-disordered breathing could be offset by a higher compliance relative to CPAP, resulting in similar health outcomes in terms of sleepiness, neurobehavioral functioning, quality of life and blood pressure. Electrical stimulation of the hypoglossal nerve is a promising treatment approach for moderate to severe OSAHS. Avoiding the supine position during sleep and reducing the overnight rostral fluid shift from the legs to the neck can also achieve a partial improvement of sleep-disordered breathing. There are currently no medications to treat OSAHS effectively. At least fifty percent of OSAHS patients are affected by central obesity and related metabolic disorders. To date, there is no evidence that treating OSAHS may improve comorbid metabolic disorders. Weight-loss intervention is a central component of the strategies used to improve the cardiovascular risk-factor profile in patients with OSAHS and obesity.

Sleep disordered breathing in pregnancy: the maternal and fetal implications

Sleep disordered breathing (SDB) which includes obstructive sleep apnoea (OSA) and upper airway resistance syndrome (UARS), has emerged as a risk factor for adverse maternal-foetal outcomes in pregnancy. Physiological changes of pregnancy predispose a woman 'at risk' towards developing SDB. The increasing incidence of OSA in pregnancy closely correlates with the population trends of obesity. Common screening tools validated in non-pregnant subjects including Epworth Sleepiness Scale (ESS) and Berlin Questionnaire (BQ) are poor predictors of SDB in pregnancy. Preeclampsia, gestational hypertension and gestational diabetes mellitus (GDM) are linked with SDB. Preeclampsia and OSA share common pathological associations. It is unclear if one predisposes the other. Foetal morbidity includes intrauterine growth restriction (IUGR), preterm delivery, low birth weight, neonatal intensive care unit (NICU) admission and Apgar score of less than seven at one minute. Continuous positive airway pressure (CPAP) is a well-documented treatment of SDB in pregnancy and has been shown to reverse some of the adverse events. It becomes imperative to diagnose and manage this condition as OSA causes substantial morbidity in the untreated pregnant patient and foetus. Three short clinical cases and a literature review on SDB on pregnancy are presented.

Positive Airway Pressure Therapy for Obstructive Sleep Apnea

Positive airway pressure (PAP) is considered first-line therapy for moderate to severe obstructive sleep apnea and may also be considered for mild obstructive sleep apnea, particularly if it is symptomatic or there are concomitant cardiovascular disorders. Continuous PAP is most commonly used. Other modes, such as bilevel airway pressure, autotitrating positive airway pressure, average volume assured pressure support, and adaptive support ventilation, play important roles in the management of sleep-related breathing disorders. This article outlines the indications, description, and comfort features of each mode. Despite the proven efficacy of PAP in treating obstructive sleep apnea syndrome and its sequelae, adherence to therapy is low. Close follow-up of patients for evaluation of adherence to and effectiveness of treatment is important.

A multicentre randomised controlled trial and economic evaluation of continuous positive airway pressure for the treatment of obstructive sleep apnoea syndrome in older people: PREDICT

BACKGROUND

The therapeutic and economic benefits of continuous positive airway pressure (CPAP) for the treatment of obstructive sleep apnoea syndrome (OSAS) have been established in middle-aged people. In older people there is a lack of evidence.

OBJECTIVE

To determine the clinical efficacy of CPAP in older people with OSAS and to establish its cost-effectiveness.

DESIGN

A randomised, parallel, investigator-blinded multicentre trial with within-trial and model-based cost-effectiveness analysis.

METHODS

Two hundred and seventy-eight patients, aged ≥ 65 years with newly diagnosed OSAS [defined as oxygen desaturation index at ≥ 4% desaturation threshold level for > 7.5 events/hour and Epworth Sleepiness Scale (ESS) score of ≥ 9] recruited from 14 hospital-based sleep services across the UK.

INTERVENTIONS

CPAP with best supportive care (BSC) or BSC alone. Autotitrating CPAP was initiated using standard clinical practice. BSC was structured advice on minimising sleepiness.

COPRIMARY OUTCOMES

Subjective sleepiness at 3 months, as measured by the ESS (ESS mean score: months 3 and 4) and cost-effectiveness over 12 months, as measured in quality-adjusted life-years (QALYs) calculated using the European Quality of Life-5 Dimensions (EQ-5D) and health-care resource use, information on which was collected monthly from patient diaries.

SECONDARY OUTCOMES

Subjective sleepiness at 12 months (ESS mean score: months 10, 11 and 12) and objective sleepiness, disease-specific and generic quality of life, mood, functionality, nocturia, mobility, accidents, cognitive function, cardiovascular risk factors and events at 3 and 12 months.

RESULTS

Two hundred and seventy-eight patients were randomised to CPAP (n = 140) or BSC (n = 138) over 27 months and 231 (83%) patients completed the trial. Baseline ESS score was similar in both groups [mean (standard deviation; SD) CPAP 11.5 (3.3), BSC 11.4 (4.2)]; groups were well balanced for other characteristics. The mean (SD) in ESS score at 3 months was -3.8 (0.4) in the CPAP group and -1.6 (0.3) in the BSC group. The adjusted treatment effect of CPAP compared with BSC was -2.1 points [95% confidence interval (CI) -3.0 to -1.3 points; p < 0.001]. At 12 months the effect was -2.0 points (95% CI -2.8 to -1.2 points; p < 0.001). The effect was greater in patients with increased CPAP use or higher baseline ESS score. The number of QALYs calculated using the EQ-5D was marginally (0.005) higher with CPAP than with BSC (95% CI -0.034 to 0.044). The average cost per patient was £1363 (95% CI £1121 to £1606) for those allocated to CPAP and £1389 (95% CI £1116 to £1662) for those allocated to BSC. On average, costs were lower in the CPAP group (mean -£35; 95% CI -£390 to £321). The probability that CPAP was cost-effective at thresholds conventionally used by the NHS (£20,000 per QALY gained) was 0.61. QALYs calculated using the Short Form questionnaire-6 Dimensions were 0.018 higher in the CPAP group (95% CI 0.003 to 0.034 QALYs) and the probability that CPAP was cost-effective was 0.96. CPAP decreased objective sleepiness (p = 0.02), increased mobility (p = 0.03) and reduced total and low-density lipoprotein cholesterol (p = 0.05, p = 0.04, respectively) at 3 months but not at 12 months. In the BSC group, there was a fall in systolic blood pressure of 3.7 mmHg at 12 months, which was not seen in the CPAP group (p = 0.04). Mood, functionality, nocturia, accidents, cognitive function and cardiovascular events were unchanged. There were no medically significant harms attributable to CPAP.

CONCLUSION

In older people with OSAS, CPAP reduces sleepiness and is marginally more cost-effective than BSC over 12 months. Further work is required in the identification of potential biomarkers of sleepiness and those patients at increased risk of cognitive impairment. Early detection of which could be used to inform the clinician when in the disease cycle treatment is needed to avert central nervous system sequelae and to assist patients decision-making regarding treatment and compliance. Treatment adherence is also a challenge in clinical trials generally, and adherence to CPAP therapy in particular is a recognised concern in both research studies and clinical practice. Suggested research priorities would include a focus on optimisation of CPAP delivery or support and embracing the technological advances currently available. Finally, the improvements in quality of life in trials do not appear to reflect the dramatic changes noted in clinical practice. There should be a greater focus on patient centred outcomes which would better capture the symptomatic improvement with CPAP treatment and translate these improvements into outcomes which could be used in health economic analysis.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN90464927.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 19, No. 40. See the NIHR Journals Library website for further project information.

Sleep disordered breathing at the extremes of age: the elderly

KEY POINTS

Sleep disordered breathing (SDB) is common and its prevalence increases with age. Despite this high prevalence, SDB is frequently unrecognised and undiagnosed in older people.There is accumulating evidence that SDB in older people is associated with worsening cardio- cerebrovascular, cognitive and functional outcomes.There is now good evidence to support the use of continuous positive airway pressure therapy in older patients with symptomatic SDB.

EDUCATIONAL AIMS

To highlight the prevalence and presentation of sleep disordered breathing (SDB) in older people.To inform readers about the risk factors for SDB in older people.To explore the impact of SDB in older people.To introduce current evidence based treatment options for SDB in older people. Sleep disordered breathing (SBD) increases in prevalence as we age, most likely due to physiological and physical changes that occur with ageing. Additionally, SDB is associated with comorbidity and its subsequent polypharmacy, which may increase with increasing age. Finally, the increased prevalence of SDB is intrinsically linked to the obesity epidemic. SDB is associated with serious outcomes in younger people and, likewise, older people. Thus, identification, diagnosis and treatment of SDB is important irrelevant of age. This article reviews the age-related changes contributing to SDB, the epidemiology and the risk factors for SDB in older people, the association of SDB with adverse outcomes, and diagnostic and treatment options for this population.

Clinical consequences and economic costs of untreated obstructive sleep apnea syndrome

Objective

To provide an overview of the healthcare and societal consequences and costs of untreated obstructive sleep apnea syndrome.

Data sources

PubMed database for English-language studies with no start date restrictions and with an end date of September 2014.

Methods

A comprehensive literature review was performed to identify all studies that discussed the physiologic, clinical and societal consequences of obstructive sleep apnea syndrome as well as the costs associated with these consequences. There were 106 studies that formed the basis of this analysis.

Conclusions

Undiagnosed and untreated obstructive sleep apnea syndrome can lead to abnormal physiology that can have serious implications including increased cardiovascular disease, stroke, metabolic disease, excessive daytime sleepiness, work-place errors, traffic accidents and death. These consequences result in significant economic burden. Both, the health and societal consequences and their costs can be decreased with identification and treatment of sleep apnea.

Implications for practice

Treatment of obstructive sleep apnea syndrome, despite its consequences, is limited by lack of diagnosis, poor patient acceptance, lack of access to effective therapies, and lack of a variety of effective therapies. Newer modes of therapy that are effective, cost efficient and more accepted by patients need to be developed.

Obstructive sleep apnoea syndrome and its management

Obstructive sleep apnoea (OSA) is a common disorder characterized by repetitive episodes of nocturnal breathing cessation due to upper airway collapse. OSA causes severe symptoms, such as excessive daytime somnolence, and is associated with a significant cardiovascular morbidity and mortality. Different treatment options are now available for an effective management of this disease. After more than three decades from its first use, continuous positive airway pressure (CPAP) is still recognized as the gold standard treatment. Nasal CPAP (nCPAP) is highly effective in controlling symptoms, improving quality of life and reducing the clinical sequelae of sleep apnoea. Other positive airway pressure modalities are available for patients intolerant to CPAP or requiring high levels of positive pressure. Mandibular advancement devices, particularly if custom made, are effective in mild to moderate OSA and provide a viable alternative for patients intolerant to CPAP therapy. The role of surgery remains controversial. Uvulopalatopharyngoplasty is a well established procedure and can be considered when treatment with CPAP has failed, whereas maxillar-mandibular surgery can be suggested to patients with a craniofacial malformation. A number of minimally invasive procedures to treat snoring are currently under evaluation. Weight loss improves symptoms and morbidity in all patients with obesity and bariatric surgery is an option in severe obesity. A multidisciplinary approach is necessary for an accurate management of the disease.

Clinical effectiveness and cost-effectiveness results from the randomised controlled Trial of Oral Mandibular Advancement Devices for Obstructive sleep apnoea-hypopnoea (TOMADO) and long-term economic analysis of oral devices and continuous positive airway pressure

BACKGROUND

Obstructive sleep apnoea-hypopnoea (OSAH) causes excessive daytime sleepiness (EDS), impairs quality of life (QoL) and increases cardiovascular disease and road traffic accident risks. Continuous positive airway pressure (CPAP) treatment is clinically effective but undermined by intolerance, and its cost-effectiveness is borderline in milder cases. Mandibular advancement devices (MADs) are another option, but evidence is lacking regarding their clinical effectiveness and cost-effectiveness in milder disease.

OBJECTIVES

(1) Conduct a randomised controlled trial (RCT) examining the clinical effectiveness and cost-effectiveness of MADs against no treatment in mild to moderate OSAH. (2) Update systematic reviews and an existing health economic decision model with data from the Trial of Oral Mandibular Advancement Devices for Obstructive sleep apnoea-hypopnoea (TOMADO) and newly published results to better inform long-term clinical effectiveness and cost-effectiveness of MADs and CPAP in mild to moderate OSAH.

TOMADO

A crossover RCT comparing clinical effectiveness and cost-effectiveness of three MADs: self-moulded [SleepPro 1™ (SP1); Meditas Ltd, Winchester, UK]; semibespoke [SleepPro 2™ (SP2); Meditas Ltd, Winchester, UK]; and fully bespoke [bespoke MAD (bMAD); NHS Oral-Maxillofacial Laboratory, Addenbrooke's Hospital, Cambridge, UK] against no treatment, in 90 adults with mild to moderate OSAH. All devices improved primary outcome [apnoea-hypopnoea index (AHI)] compared with no treatment: relative risk 0.74 [95% confidence interval (CI) 0.62 to 0.89] for SP1; relative risk 0.67 (95% CI 0.59 to 0.76) for SP2; and relative risk 0.64 (95% CI 0.55 to 0.76) for bMAD (p < 0.001). Differences between MADs were not significant. Sleepiness [as measured by the Epworth Sleepiness Scale (ESS)] was scored 1.51 [95% CI 0.73 to 2.29 (SP1)] to 2.37 [95% CI 1.53 to 3.22 (bMAD)] lower than no treatment (p < 0.001), with SP2 and bMAD significantly better than SP1. All MADs improved disease-specific QoL. Compliance was lower for SP1, which was unpopular at trial exit. At 4 weeks, all devices were cost-effective at £20,000/quality-adjusted life-year (QALY), with SP2 the best value below £39,800/QALY.

META-ANALYSIS

A MEDLINE, EMBASE and Science Citation Index search updating two existing systematic reviews (one from November 2006 and the other from June 2008) to August 2013 identified 77 RCTs in adult OSAH patients comparing MAD with conservative management (CM), MADs with CPAP or CPAP with CM. MADs and CPAP significantly improved AHI [MAD -9.3/hour (p < 0.001); CPAP -25.4/hour (p < 0.001)]. Effect difference between CPAP and MADs was 7.0/hour (p < 0.001), favouring CPAP. No trials compared CPAP with MADs in mild OSAH. MAD and CPAP reduced the ESS score similarly [MAD 1.6 (p < 0.001); CPAP 1.6 (p < 0.001)].

LONG-TERM COST-EFFECTIVENESS

An existing model assessed lifetime cost-utility of MAD and CPAP in mild to moderate OSAH, using the revised meta-analysis to update input values. The TOMADO provided utility estimates, mapping ESS score to European Quality of Life-5 Dimensions three-level version for device cost-utility. Using SP2 as the standard device, MADs produced higher mean costs and mean QALYs than CM [incremental cost-effectiveness ratio (ICER) £6687/QALY]. From a willingness to pay (WTP) of £15,367/QALY, CPAP is cost-effective, although the likelihood of MADs (p = 0.48) and CPAP (p = 0.49) being cost-effective is very similar. Both were better than CM, but there was much uncertainty in the choice between CPAP and MAD (at a WTP £20,000/QALY, the probability of being the most cost-effective was 47% for MAD and 52% for CPAP). When SP2 lifespan increased to 18 months, the ICER for CPAP compared with MAD became £44,066. The ICER for SP1 compared with CM was £1552, and for bMAD compared with CM the ICER was £13,836. The ICER for CPAP compared with SP1 was £89,182, but CPAP produced lower mean costs and higher mean QALYs than bMAD. Differential compliance rates for CPAP reduces cost-effectiveness so MADs become less costly and more clinically effective with CPAP compliance 90% of SP2.

CONCLUSIONS

Mandibular advancement devices are clinically effective and cost-effective in mild to moderate OSAH. A semi-bespoke MAD is the appropriate first choice in most patients in the short term. Future work should explore whether or not adjustable MADs give additional clinical and cost benefits. Further data on longer-term cardiovascular risk and its risk factors would reduce uncertainty in the health economic model and improve precision of effectiveness estimates.

TRIAL REGISTRATION

This trial is registered as ISRCTN02309506.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 18, No. 67. See the NIHR Journals Library website for further project information.

A Cost-Effectiveness Analysis of Surgery for Middle-Aged Men with Severe Obstructive Sleep Apnea Intolerant of CPAP

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is associated with increased cardiovascular morbidity and mortality. Conventional OSA therapy necessitates indefinite continuous positive airway pressure (CPAP). Although CPAP is an effective treatment modality, up to 50% of OSA patients are intolerant of CPAP. We explore whether surgical modalities developed for those intolerant of CPAP are cost-effective.

METHODS

We construct a lifetime semi-Markov model of OSA that accounts for observed increased risks of stroke, cardiovascular disease, and motor vehicle collisions for a 50-year-old male with untreated severe OSA. Using this model, we compare the cost-effectiveness of (1) no treatment, (2) CPAP only, and (3) CPAP followed by surgery (either palatopharyngeal reconstructive surgery [PPRS] or multilevel surgery [MLS]) for those intolerant to CPAP.

RESULTS

Compared with the CPAP only strategy, CPAP followed by PPRS (CPAP-PPRS) adds 0.265 quality adjusted life years (QALYs) for an increase of $2,767 (discounted 2010 dollars) and is highly cost effective with an incremental cost-effectiveness ratio (ICER) of $10,421/QALY for a 50-year-old male with severe OSA. Compared to a CPAP-PPRS strategy, the CPAP-MLS strategy adds 0.07 QALYs at an increase of $6,213 for an ICER of $84,199/QALY. The CPAP-PPRS strategy appears cost-effective over a wide range of parameter estimates.

CONCLUSIONS

Palatopharyngeal reconstructive surgery appears cost-effective in middle-aged men with severe OSA intolerant of CPAP. Further research is warranted to better define surgical candidacy as well as short-term and long-term surgical outcomes.

COMMENTARY

A commentary on this article appears in this issue on page 509.

Quality measures for the care of adult patients with obstructive sleep apnea

ABSTRACT

Obstructive sleep apnea (OSA) is a prevalent disorder associated with a multitude of adverse outcomes when left untreated. There is significant heterogeneity in the evaluation and management of OSA resulting in variation in cost and outcomes. Thus, the goal for developing these measures was to have a way to evaluate the outcomes and reliability of the processes involved with the standard care approaches used in the diagnosis and management of OSA. The OSA quality care measures presented here focus on both outcomes and processes. The AASM commissioned the Adult OSA Quality Measures Workgroup to develop quality care measures aimed at optimizing care for adult patients with OSA. These quality care measures developed by the Adult OSA Quality Measures Workgroup are an extension of the original Centers for Medicare & Medicaid Services (CMS) approved Physician Quality Reporting System (PQRS) measures group for OSA. The measures are based on the available scientific evidence, focus on public safety, and strive to improve quality of life and cardiovascular outcomes for individual OSA patients. The three outcomes that were selected were as follows: (1) improve disease detection and categorization; (2) improve quality of life; and (3) reduce cardiovascular risk. After selecting these relevant outcomes, a total of ten process measures were chosen that could be applied and assessed for the purpose of accomplishing these outcomes. In the future, the measures described in this document may be reported through the PQRS in addition to, or as a replacement for, the current OSA measures group. The overall objective for the development of these measures is that implementation of these quality measures will result in improved patient outcomes, reduce the public health burden of OSA, and provide a measurable standard for evaluating and managing OSA.

An evidence-based approach to the management of snoring in adults

BACKGROUND

Snoring is frequently encountered by the otolaryngologist. Given its significant impact on quality of life and that it is a symptom of sleep-related breathing disorders, diagnosis and treatment are of major importance. In particular, the diagnosis should aim to distinguish between simple snoring and obstructive sleep apnoea. This article aims to provide a systematic, concise and evidence-based method of managing the adult patient with snoring.

METHOD

This review was based on a literature search last undertaken on 30 June 2014. The MEDLINE, EMBASE and Cochrane databases were searched using the subject headings snoring and obstructive sleep apnoea in adults in combination with classification, diagnosis, investigations, management, treatment and surgery. Results were limited to English language articles including case series, clinical trials, randomised controlled trials, meta-analyses, systematic reviews and review articles. Relevant references from selected articles were also reviewed.

RESULTS

The majority of published literature for snoring is of level II/III evidence and that for obstructive sleep apnoea being of level I/II, with 36 relevant randomised controlled trials identified. The diagnosis of obstructive sleep apnoea involves thorough clinical assessment and typically a sleep study. Snoring may be managed with lifestyle modification, intra-oral devices or by surgical intervention, with continuous positive airway pressure being the treatment of choice for moderate-to-severe obstructive sleep apnoea.

CONCLUSIONS

A structured history of snoring and its associated symptoms, comprehensive examination including flexible laryngoscopy and sleep studies where relevant, in addition to targeted investigations, should lead to the correct diagnosis and appropriate management.