Continuous positive airway pressure treatment of sleepy patients with milder obstructive sleep apnea: results of the CPAP Apnea Trial North American Program (CATNAP) randomized clinical trial

Phenotypes in obstructive sleep apnea: A definition, examples and evolution of approaches

Obstructive sleep apnea (OSA) is a complex and heterogeneous disorder and the apnea hypopnea index alone can not capture the diverse spectrum of the condition. Enhanced phenotyping can improve prognostication, patient selection for clinical trials, understanding of mechanisms, and personalized treatments. In OSA, multiple condition characteristics have been termed "phenotypes." To help classify patients into relevant prognostic and therapeutic categories, an OSA phenotype can be operationally defined as: "A category of patients with OSA distinguished from others by a single or combination of disease features, in relation to clinically meaningful attributes (symptoms, response to therapy, health outcomes, quality of life)." We review approaches to clinical phenotyping in OSA, citing examples of increasing analytic complexity. Although clinical feature based OSA phenotypes with significant prognostic and treatment implications have been identified (e.g., excessive daytime sleepiness OSA), many current categorizations lack association with meaningful outcomes. Recent work focused on pathophysiologic risk factors for OSA (e.g., arousal threshold, craniofacial morphology, chemoreflex sensitivity) appears to capture heterogeneity in OSA, but requires clinical validation. Lastly, we discuss the use of machine learning as a promising phenotyping strategy that can integrate multiple types of data (genomic, molecular, cellular, clinical) to identify unique, meaningful OSA phenotypes.

Obstructive Sleep Apnea in Women: Specific Issues and Interventions

Obstructive sleep apnea (OSA) has traditionally been seen as a male disease. However, the importance of OSA in women is increasingly being recognized, along with a number of significant gender-related differences in the symptoms, diagnosis, consequences, and treatment of OSA. Women tend to have less severe OSA than males, with a lower apnea-hypopnea index (AHI) and shorter apneas and hypopneas. Episodes of upper airway resistance that do not meet the criteria for apneas are more common in women. Prevalence rates are lower in women, and proportionally fewer women receive a correct diagnosis. Research has also documented sex differences in the upper airway, fat distribution, and respiratory stability in OSA. Hormones are implicated in some gender-related variations, with differences between men and women in the prevalence of OSA decreasing as age increases. The limited data available suggest that although the prevalence and severity of OSA may be lower in women than in men, the consequences of the disease are at least the same, if not worse for comparable degrees of severity. Few studies have investigated gender differences in the effects of OSA treatment. However, given the differences in physiology and presentation, it is possible that personalized therapy may provide more optimal care.

Comparative efficacy of CPAP, MADs, exercise-training, and dietary weight loss for sleep apnea: a network meta-analysis

STUDY OBJECTIVE

To synthesize evidence from available studies on the relative efficacies of continuous positive airway pressure (CPAP), mandibular advancement device (MAD), supervised aerobic exercise training, and dietary weight loss in patients with obstructive sleep apnea (OSA).

DESIGN

Network meta-analysis of 80 randomized controlled trials (RCTs) short-listed from PubMed, SCOPUS, Web of science, and Cochrane register (inception - September 8, 2015).

PATIENTS

Individuals with OSA.

INTERVENTIONS

CPAP, MADs, exercise training, and dietary weight loss.

RESULTS

CPAP decreased apnea-hypopnea index (AHI) the most [by 25.27 events/hour (22.03-28.52)] followed by exercise training, MADs, and dietary weight loss. While the difference between exercise training and CPAP was non-significant [-8.04 (-17.00 to 0.92), a significant difference was found between CPAP and MADs on AHI and oxygen desaturation index (ODI) [-10.06 (-14.21 to -5.91) and -7.82 (-13.04 to -2.59), respectively]. Exercise training significantly improved Epworth sleepiness scores (ESS) [by 3.08 (0.68-5.48)], albeit with a non-significant difference compared to MADs and CPAP.

CONCLUSIONS

CPAP is the most efficacious in complete resolution of sleep apnea and in improving the indices of saturation during sleep. While MADs offer a reasonable alternative to CPAP, exercise training which significantly improved daytime sleepiness (ESS) could be used as adjunctive to the former two.

Short-Term Variability in Apnea-Hypopnea Index during Extended Home Portable Monitoring

STUDY OBJECTIVES

Apnea-hypopnea index (AHI) is the primary measure used to confirm a diagnosis of obstructive sleep apnea (OSA). However, there may be significant night-to-night variability (NNV) in AHI, limiting the value of AHI in clinical decision-making related to OSA management. We examined short-term NNV in AHI and its predictors during home portable monitoring (PM).

METHODS

Single center prospective observational study of patients (n = 84) with newly diagnosed OSA by polysomnography (PSG) AHI ≥ 5/h. All participants underwent 2 to 8 consecutive nights of PM.

RESULTS

Participants (n = 84) were middle-aged (47 ± 8.3 y, mean ± standard deviation; SD), including 28 women, with mean AHI on baseline PSG (AHIPSG) of 30.1 ± 31.8. Mean AHI on PM (AHIPM) was 27.4 ± 23.7. Intraclass correlation coefficient (ICC) for AHIPM in the entire sample was 0.73 (95% CI 0.66-0.8), indicating that 27% of the variability in AHIPM was due to intra-individual factors. Mild severity of OSA, defined by AHIPSG 5-15/h, was associated with higher NNV (likelihood ratio, -0.4 ± 0.14; p = 0.006) and absence of comorbidity showed a trend towards higher NNV (-0.54 ± 0.27, p = 0.05) on AHIPM.

CONCLUSIONS

The intraindividual short-term NNV in AHIPM is higher in mild versus moderately severe OSA, even in the home setting, where first-night effect is not expected. Larger studies of NNV focused on patients with mild OSA are needed to identify characteristics that predict need and timing for repeated diagnostic testing and treatment.

COMMENTARY

A commentary on this article appears in this issue on page 787.

Meta-analysis of randomised controlled trials of oral mandibular advancement devices and continuous positive airway pressure for obstructive sleep apnoea-hypopnoea

Obstructive sleep apnoea-hypopnoea (OSAH) causes excessive daytime sleepiness, impairs quality-of-life, and increases cardiovascular disease and road traffic accident risks. Continuous positive airway pressure (CPAP) treatment and mandibular advancement devices (MAD) have been shown to be effective in individual trials but their effectiveness particularly relative to disease severity is unclear. A MEDLINE, Embase and Science Citation Index search updating two systematic reviews to August 2013 identified 77 RCTs in adult OSAH patients comparing: MAD with conservative management (CM); MAD with CPAP; or CPAP with CM. Overall MAD and CPAP significantly improved apnoea-hypopnoea index (AHI) (MAD -9.3/hr (p < 0.001), CPAP -25.4 (p < 0.001)). In direct comparisons mean AHI and Epworth sleepiness scale score were lower (7.0/hr (p < 0.001) and 0.67 (p = 0.093) respectively) for CPAP. There were no CPAP vs. MAD trials in mild OSAH but in comparisons with CM, MAD and CPAP reduced ESS similarly (MAD 2.01 (p < 0.001); CPAP 1.23 (p = 0.012). Both MAD and CPAP are clinically effective in the treatment of OSAH. Although CPAP has a greater treatment effect, MAD is an appropriate treatment for patients who are intolerant of CPAP and may be comparable to CPAP in mild disease.

Mild obstructive sleep apnoea: clinical relevance and approaches to management

Obstructive sleep apnoea is highly prevalent in the general population worldwide, especially in its mild form. Clinical manifestations correlate poorly with disease severity measured by the apnoea-hypopnoea index (AHI), which complicates diagnosis. Full polysomnography might be more appropriate to assess suspected mild cases because limited ambulatory diagnostic systems are least accurate in mild disease. Treatment options in mild obstructive sleep apnoea include continuous positive airway pressure (CPAP) and oral appliance therapy, in addition to positional therapy and weight reduction when appropriate. The superior efficacy of CPAP in reducing AHI is offset by greater tolerance of oral appliances, especially in mild disease. Although severe obstructive sleep apnoea is associated with adverse health consequences, including cardiometabolic comorbidities, the association with mild disease is unclear, and reports differ regarding the clinical relevance of mild obstructive sleep apnoea. Improved diagnostic techniques and evidence-based approaches to management in mild obstructive sleep apnoea require further research.

Upper Airway Resistance Syndrome Patients Have Worse Sleep Quality Compared to Mild Obstructive Sleep Apnea

Purpose

To compare sleep quality and sustained attention of patients with Upper Airway Resistance Syndrome (UARS), mild Obstructive Sleep Apnea (OSA) and normal individuals.

Methods

UARS criteria were presence of excessive daytime sleepiness (Epworth Sleepiness Scale—ESS—≥ 10) and/or fatigue (Modified Fatigue Impact Scale—MFIS—≥ 38) associated to Apnea/hypopnea index (AHI) ≤ 5 and Respiratory Disturbance Index (RDI) > 5 events/hour of sleep or more than 30% of total sleep time with flow limitation. Mild OSA was considered if the presence of excessive daytime sleepiness (ESS ≥ 10) and/or fatigue (MFIS ≥ 38) associated to AHI ≥ 5 and ≤ 15 events/hour. “Control group” criteria were AHI < 5 events/hour and RDI ≤ 5 events/hour and ESS ≤ 9, without any sleep, clinical, neurological or psychiatric disorder. 115 individuals (34 UARS and 47 mild OSA patients and 34 individuals in “control group”), adjusted for age, gender, body mass index (BMI) and schooling years, performed sleep questionnaires and sustained attention evaluation. Psychomotor Vigilance Task (PVT) was performed five times (each two hours) from 8 a.m. to 4 p.m.

Results

UARS patients had worse sleep quality (Functional Outcomes of Sleep Questionnaire—FOSQ—and Pittsburgh Sleep Quality Index—PSQI: p < 0.05) and more fatigue than mild OSA patients (p = 0.003) and scored significantly higher in both Beck inventories than “control group” (p < 0.02). UARS patients had more lapses early in the morning (in time 1) compared to the results in the afternoon (time 5) than mild OSA (p = 0.02). Mild OSA patients had more lapses in times 2 than in time 5 compared to “control group” (p = 0.04).

Conclusions

UARS patients have a worse sleep quality, more fatigue and a worse early morning sustained attention compared to mild OSA. These last had a worse sustained attention than controls.

Effect of nocturia on next-day sedentary activity in adults with type 2 diabetes

PURPOSE

Nocturia, a common cause of disturbed sleep quality and next-day fatigue, may contribute to difficulty with diabetes self-management. The purpose of this study was to examine the effect nocturia has on next-day subjectively measured mental and physical energy and objectively measured physical activity.

METHODS

This secondary analysis utilized sleep diaries over one week which measured nocturia frequency and other sleep quality indicators (wake after sleep onset, sleep quality and sleep duration) along with next-day reports of mental and physical energy. Next-day physical activity was measured with the BodyMedia Sensewear armband.

RESULTS

Sleep quality and sleep duration were associated with next-day physical and mental energy. Nocturia frequency (≥2 times per night) was associated with increased next-day sedentary activity.

CONCLUSION

These results suggest that nocturia could negatively affect next-day physical activity in people with diabetes.

A review of neurocognitive function and obstructive sleep apnea with or without daytime sleepiness

Excessive daytime sleepiness (EDS) and neurocognitive dysfunction are commonly observed in patients with obstructive sleep apnea (OSA), and these daytime functional deficits can be reversed partly or completely with treatment such as continuous positive airway pressure (CPAP). Although daytime sleepiness is a possible etiology for neurocognitive dysfunction in OSA patients, EDS is not universally present in all patients with OSA. The objective of this review is to summarize the relationship between neurocognitive function and EDS in OSA, as well as the difference in cognitive domains, improvement, and application of CPAP therapy between patients with and without EDS. Two authors independently searched PubMED/Medline, The Cochrane Library and Scopus through May 27, 2015. Sixty-five articles were included in this review. The literature demonstrated a wide range of neurocognitive deficits in OSA patients with EDS, but no more extensive and complex cognitive domains (eg, executive function) in patients without EDS. However, the current literature had very few studies with large sample sizes and extended follow-up that evaluated the effect of CPAP for OSA in patients with and without sleepiness. CPAP failed to improve cognitive dysfunction in OSA patients without EDS after short-term therapy. The evidence suggests that daytime sleepiness possibly relates to the domain and extent of cognitive impairments in OSA, and CPAP therapy has little effect on the improvement of cognitive deficits in OSA patients without EDS. We recommend that additional prospective studies be performed to further quantify the relationship between neurocognitive function in OSA patients with and without EDS.

Remote Ambulatory Management of Veterans with Obstructive Sleep Apnea

STUDY OBJECTIVES

Despite significant medical sequelae of obstructive sleep apnea (OSA), the condition remains undiagnosed and untreated in many affected individuals. We explored the feasibility of a comprehensive, telemedicine-based OSA management pathway in a community-based Veteran cohort.

METHODS

This prospective, parallel-group randomized pilot study assessed feasibility of a telemedicine-based pathway for OSA evaluation and management in comparison to a more traditional, in-person care model. The study included 60 Veterans at the Philadelphia Veterans Affairs Medical Center and two affiliated community-based outpatient clinics. Telemedicine pathway feasibility, acceptability, and outcomes were assessed through a variety of quantitative (Functional Outcomes of Sleep Questionnaire, dropout rates, positive airway pressure [PAP] adherence rates, participant satisfaction ratings) and qualitative (verbal feedback) metrics.

RESULTS

There was no significant difference in functional outcome changes, patient satisfaction, dropout rates, or objectively measured PAP adherence between groups after 3 months of treatment. Telemedicine participants showed greater improvement in mental health scores, and their feedback was overwhelmingly positive.

CONCLUSIONS

Our pilot study suggests that telemedicine-based management of OSA patients is feasible in terms of patient functional outcomes and overall satisfaction with care. Future studies should include larger populations to further elucidate these findings while assessing provider- and patient-related cost effectiveness.

Nocturnal hypoxemia severity and renin-angiotensin system activity in obstructive sleep apnea

RATIONALE

Obstructive sleep apnea (OSA) and nocturnal hypoxemia are associated with chronic kidney disease and up-regulation of the renin-angiotensin system (RAS), which is deleterious to renal function. The extent to which the magnitude of RAS activation is influenced by the severity of nocturnal hypoxemia and comorbid obesity has not been determined.

OBJECTIVES

To determine the association between the severity of nocturnal hypoxemia and RAS activity and whether this is independent of obesity in patients with OSA.

METHODS

Effective renal plasma flow (ERPF) response to angiotensin II (AngII) challenge, a marker of renal RAS activity, was measured by paraaminohippurate clearance technique in 31 OSA subjects (respiratory disturbance index, 51 ± 25 h(-1)), stratified according to nocturnal hypoxemia status (mean nocturnal SaO2, ≥90% [moderate hypoxemia] or <90% [severe hypoxemia]) and 13 obese control subjects.

MEASUREMENTS AND MAIN RESULTS

Compared with control subjects, OSA subjects demonstrated decreased renovascular sensitivity (ERPF, -153 ± 79 vs. -283 ± 31 ml/min; P = 0.004) (filtration fraction, 5.4 ± 3.8 vs. 7.1 ± 2.6%; P = 0.0025) in response to 60 minutes of AngII challenge (mean ± SD; all P values OSA vs. control). The fall in ERPF in response to AngII was less in patients with severe hypoxemia compared with those with moderate hypoxemia (P = 0.001) and obese control subjects after 30 minutes (P < 0.001) and 60 minutes (P < 0.001) of AngII challenge, reflecting more augmented renal RAS activity. Severity of hypoxemia was not associated with the blood pressure or the systemic circulating RAS component response to AngII.

CONCLUSIONS

The severity of nocturnal hypoxemia influences the magnitude of renal, but not the systemic, RAS activation independently of obesity in patients with OSA.

Effect of Sleep Disturbances on Quality of Life, Diabetes Self-Care Behavior, and Patient-Reported Outcomes

IN BRIEF Poor sleep quality and sleep disorders, particularly insomnia, obstructive sleep apnea, and restless legs syndrome, are prevalent among people with type 2 diabetes. Evidence suggests that coexisting diabetes and sleep disturbances are associated with decreases in quality of life, diabetes self-care behaviors, and patient-reported outcomes. Additional research is required to determine the effect of treatment of sleep disorders on patient-centered outcomes in people with type 2 diabetes.

OSA Syndrome and Posttraumatic Stress Disorder: Clinical Outcomes and Impact of Positive Airway Pressure Therapy

BACKGROUND

We sought to determine the impact of OSA syndrome (OSAS) on symptoms and quality of life (QoL) among patients with posttraumatic stress disorder (PTSD). In addition, we assessed adherence and response to positive airway pressure (PAP) therapy in this population.

METHODS

This was a case-controlled observational cohort study at the Sleep Disorders Center of an academic military medical center. Two hundred consecutive patients with PTSD underwent sleep evaluations. Patients with PTSD with and without OSAS were compared with 50 consecutive age-matched patients with OSAS without PTSD and 50 age-matched normal control subjects. Polysomnographic data, sleep-related symptoms and QoL measures, and objective PAP usage were obtained.

RESULTS

Among patients with PTSD, more than one-half (56.6%) received a diagnosis of OSAS. Patients with PTSD and OSAS had lower QoL and more somnolence compared with the other groups. Patients with PTSD demonstrated significantly lower adherence and response to PAP therapy. Resolution of sleepiness occurred in 82% of patients with OSAS alone, compared with 62.5% of PAP-adherent and 21.4% of nonadherent patients with PTSD and OSAS (P < .001). Similarly, posttreatment Functional Outcomes of Sleep Questionnaire ≥ 17.9 was achieved in 72% of patients with OSAS, compared with only 56.3% of patients with PTSD and OSA who were PAP adherent and 26.2% who were nonadherent (P < .03).

CONCLUSIONS

In patients with PTSD, comorbid OSAS is associated with worsened symptoms, QoL, and adherence and response to PAP. Given the negative impact on outcomes, the possibility of OSAS should be considered carefully in patients with PTSD. Close follow-up is needed to optimize PAP adherence and efficacy in this at-risk population.

STOP-BANG questionnaire as a screening tool for diagnosis of obstructive sleep apnea by unattended portable monitoring sleep study

The Snoring, Tiredness, Observed apnea, high blood Pressure (STOP)-Body mass index (BMI), Age, Neck circumference, and Gender (BANG) questionnaire is a well validated screening tool for diagnosis of Obstructive sleep apnea (OSA) by an in- lab sleep study. However, performance of STOP-BANG as a screening tool for diagnosis of OSA in patients undergoing portable monitoring (PM) sleep study has not been well validated. We conducted a retrospective chart review of patients older than 18 years who had unattended portable monitoring sleep study done at a VA medical center between June 2012 and October 2014. STOP-BANG questionnaire and Epworth sleepiness scale (ESS) were routinely done prior to study. Sensitivity, specificity, and positive predictive value (PPV) various STOP-BANG score thresholds were calculated for diagnosis of OSA defined by Apnea Hypopnea Index (AHI) ≥5. Out of 502 unattended portable monitoring sleep studies, there were 465 males and 37 females. STOP-BANG thresholds of ≥2 and 3 have high sensitivity of 99.8 and 98.9 %, respectively, but very low specificity. Higher score thresholds of ≥7 and 8 have high specificity of 95 and 98.3 %, and PPV of 98.1 and 98.5 %, respectively, but very low sensitivity. A threshold of ≥7 in patients with BMI ≥30 was 100 % specific. The false negative rate for unattended portable monitoring sleep study compared to in-lab study was 80 %. STOP-BANG score thresholds of ≥7 and 8 are highly specific and have high PPV and therefore can potentially reduce need of diagnostic sleep studies in selected patients. Score thresholds of ≤2 or 3 are highly sensitive for AHI ≥5 by unattended portable monitoring sleep study but have high false negative rates. Therefore, in-lab sleep study should be performed to rule out OSA.

Impaired sustained attention and lapses are present in patients with mild obstructive sleep apnea

BACKGROUND

Severe obstructive sleep apnea (OSA) directly affects the quality of life, mood, and sustained attention of individuals, but it has not yet been established in the literature, if these changes also affect patients with mild OSA. The purpose of this study was to investigate such negative effects on the parameters described above.

METHODS

A controlled study was held at the Universidade Federal de Sao Paulo, Department of Psychobiology. Thirty-nine mild OSA patients and 25 controls were included. Volunteers could be of both genders with body mass index (BMI) ≤35 kg/m(2) and age between 18 and 65 years. Both groups were subjected to full-night polysomnography (PSG), the subjective assessment of mood (Beck Inventory of Anxiety and Depression), Functional Outcomes of Sleep Questionnaire (FOSQ), and the psychomotor vigilance task (PVT) five times during the day. We considered mild OSA patients those with apnea-hypopnea index (AHI) score between 5 and 15. The control group included subjects with AHI scores <5, respiratory disturbance index (RDI) scores ≤5, arousal index values ≤15, and Epworth Sleepiness Scale (ESS) values ≤9.

RESULTS

Mild OSA patients were older and more obese than the controls. After adjusting for age, BMI, and schooling years, there was an increased number of total lapses (3.90 ± 4.16 and 2.43 ± 5.55, p = 0.004).

CONCLUSIONS

Patients with mild OSA showed increased sustained attention lapses compared with normal subjects.

Comparison of the effects of continuous positive airway pressure and mandibular advancement devices on sleepiness in patients with obstructive sleep apnoea: a network meta-analysis

BACKGROUND

Excessive daytime sleepiness is the most important symptom of obstructive sleep apnoea and can affect work productivity, quality of life, and the risk of road traffic accidents. We aimed to quantify the effects of the two main treatments for obstructive sleep apnoea (continuous positive airway pressure and mandibular advancement devices) on daytime sleepiness and to establish predictors of response to continuous positive airway pressure.

METHODS

We searched MEDLINE and the Cochrane Library from inception to May 31, 2015, to identify randomised controlled trials comparing the effects of continuous positive airway pressure, mandibular advancement devices or an inactive control (eg, placebo or no treatment) on the Epworth Sleepiness Scale (ESS, range 0-24 points) in patients with obstructive sleep apnoea. We did a network meta-analysis using multivariate random-effects meta-regression to assess the effect of each treatment on ESS. We used meta-regression to assess the association of the reported effects of continuous positive airway pressure versus inactive controls with the characteristics of trials and their risk of bias.

FINDINGS

We included 67 studies comprising 6873 patients in the meta-analysis. Compared with an inactive control, continuous positive airway pressure was associated with a reduction in ESS score of 2·5 points (95% CI 2·0-2·9) and mandibular advancement devices of 1·7 points (1·1-2·3). We estimated that, on average, continuous positive airway pressure reduced the ESS score by a further 0·8 points compared with mandibular advancement devices (95% CI 0·1-1·4; p=0·015). However, there was a possibility of publication bias in favour of continuous positive airway pressure that might have resulted in this difference. We noted no evidence that studies reporting higher continuous positive airway pressure adherence also reported larger treatment effects (p=0·70).

INTERPRETATION

Continuous positive airway pressure and mandibular advancement devices are effective treatments for reducing daytime sleepiness in patients with obstructive sleep apnoea. Continuous positive airway pressure seemed to be a more effective treatment than mandibular advancement devices, and had an increasingly larger effect in more severe or sleepier obstructive sleep apnoea patients when compared with inactive controls. However, mandibular advancement devices are an effective alternative treatment should continuous positive airway pressure not be tolerated.

FUNDING

Swiss National Science Foundation and the University of Zurich Clinical Research Priority Program Sleep and Health.

Socio-Economic Status: A Barrier to Access to Mandibular Advancement Device Therapy for Patients with Obstructive Sleep Apnea Syndrome in France

Background

Obstructive sleep apnea syndrome (OSAS) is a major public health problem which affects between 5 to 10% of the general population. OSAS is known to be associated with high rates of morbidity and mortality mainly due to cardiovascular diseases and traffic accidents. The burden of illness is high for the individual and society. There are 2 treatment options for OSAS, Continuous Positive Airway Pressure (CPAP) and Mandibular Advancement Device therapy (MAD). CPAP is known to be an effective but very constraining treatment. Patients are usually poorly adherent. MAD is a more recent treatment easier to use and consequently better tolerated, but MAD can only be prescribed to patients with satisfactory oral hygiene. Oral health constitutes a real issue particularly among underprivileged groups in France. Through this link, the question of whether low socio-economic status constitutes a barrier to access to care for patients with OSAS is raised.

Methods and Principal Findings

In a multicenter prospective cohort of 2822 consecutive OSAS patients in whom MAD has been proposed as an alternative to CPAP between May 15, 2007 and December 1st, 2014, we identified the factors that lead to a patient diagnosed with OSAS to be treated by MAD instead of CPAP. A logistic regression was performed using a stepwise forward procedure. The main outcome of the study was that treatment by MAD was significantly associated with both educational attainment, as determined by the age at which the patient left full-time education, ≥18 years compared with <18 (adjusted odds ratio (aOR): 1.64, 95% CI 1.23 to 2.20), and the patient's occupational category. Executives and higher intellectual professions, intermediate professions, technicians, foremen and employees were significantly more likely to be treated by MAD than workers (aOR: 2.21, 95% CI 1.88 to 2.58; aOR: 1.74, 95% CI 1.15 to 2.63; aOR: 1.96, 95% CI 1.11 to 3.47, respectively).

Conclusions

Overall, these results suggest that low socio-economic status constitutes a barrier to access to MAD for patients with OSAS in France. MAD use in patients with OSAS highlights inequalities in health care access.

New developments in the use of positive airway pressure for obstructive sleep apnea

Obstructive sleep apnea (OSA) is a disorder which afflicts a large number of individuals around the world. OSA causes sleepiness and is a major cardiovascular risk factor. Since its inception in the early 1980's, continuous positive airway pressure (CPAP) has emerged as the major treatment of OSA, and it has been shown to improve sleepiness, hypertension, and a number of cardiovascular indices. Despite its successes, adherence with treatment remains a major limitation. Herein we will review the evidence behind the use of positive airway pressure (PAP) therapy, its various modes, and the methods employed to improve adherence. We will also discuss the future of PAP therapy in OSA and personalization of care.

Effect of telemetric monitoring in the first 30 days of continuous positive airway pressure adaptation for obstructive sleep apnoea syndrome – a controlled pilot study

Obstructive sleep apnoea syndrome (OSAS) is characterised by repetitive collapse of the upper airway during sleep. Continuous positive airway pressure (CPAP) applied via a mask is the standard treatment for OSAS. CPAP adherence is crucial in therapy to prevent the deleterious consequences of OSAS. We hypothesised that a combination of supervision by telemetry together with targeted telephone support in the first month of CPAP would increase CPAP adherence and treatment success. A total of 113 OSAS patients followed by telemetry-triggered interventions used the device for 5.3 h/night on 28/30 nights, significantly more than the 110 OSAS patients in the control group with 4.6 h/night and 27/30 nights. Telemetry-triggered interventions have a significant impact on adherence rate in early CPAP treatment. These results can be reached with an acceptable additional effort.

Consensus and evidence-based Indian initiative on obstructive sleep apnea guidelines 2014 (first edition)

Obstructive sleep apnea (OSA) and obstructive sleep apnea syndrome (OSAS) are subsets of sleep-disordered breathing. Awareness about OSA and its consequences among the general public as well as the majority of primary care physicians across India is poor. This necessitated the development of the Indian initiative on obstructive sleep apnea (INOSA) guidelines under the auspices of Department of Health Research, Ministry of Health and Family Welfare, Government of India. OSA is the occurrence of an average five or more episodes of obstructive respiratory events per hour of sleep with either sleep-related symptoms or co-morbidities or ≥15 such episodes without any sleep-related symptoms or co-morbidities. OSAS is defined as OSA associated with daytime symptoms, most often excessive sleepiness. Patients undergoing routine health check-up with snoring, daytime sleepiness, obesity, hypertension, motor vehicular accidents, and high-risk cases should undergo a comprehensive sleep evaluation. Medical examiners evaluating drivers, air pilots, railway drivers, and heavy machinery workers should be educated about OSA and should comprehensively evaluate applicants for OSA. Those suspected to have OSA on comprehensive sleep evaluation should be referred for a sleep study. Supervised overnight polysomnography is the “gold standard” for evaluation of OSA. Positive airway pressure (PAP) therapy is the mainstay of treatment of OSA. Oral appliances (OA) are indicated for use in patients with mild to moderate OSA who prefer OA to PAP, or who do not respond to PAP or who fail treatment attempts with PAP or behavioral measures. Surgical treatment is recommended in patients who have failed or are intolerant to PAP therapy.

Eight Hours of Nightly Continuous Positive Airway Pressure Treatment of Obstructive Sleep Apnea Improves Glucose Metabolism in Patients with Prediabetes. A Randomized Controlled Trial

RATIONALE

Although obstructive sleep apnea (OSA) is associated with impaired glucose tolerance and diabetes, it remains unclear whether OSA treatment with continuous positive airway pressure (CPAP) has metabolic benefits.

OBJECTIVES

To determine the effect of 8-hour nightly CPAP treatment on glucose metabolism in individuals with prediabetes and OSA.

METHODS

In a randomized controlled parallel group study, 39 participants were randomly assigned to receive either 8-hour nightly CPAP (n = 26) or oral placebo (n = 13). Sleep was polysomnographically recorded in the laboratory on each night. CPAP adherence was ensured by continuous supervision. Participants continued their daily routine activities outside the laboratory. Glucose metabolism was assessed at baseline and after 2 weeks of assigned treatment using both the oral and intravenous glucose tolerance tests. The primary outcome was the overall glucose response as quantified by the area under the curve for glucose during 2-hour oral glucose tolerance testing. Secondary outcomes included fasting and 2-hour glucose and insulin, the area under the curves for insulin and insulin secretion, norepinephrine, insulin sensitivity, acute insulin response to glucose, and 24-hour blood pressure.

MEASUREMENTS AND MAIN RESULTS

The overall glucose response was reduced (treatment difference: -1,276.9 [mg/dl] · min [95% confidence interval, -2,392.4 to -161.5]; P = 0.03) and insulin sensitivity was improved (treatment difference: 0.77 [mU/L](-1) · min(-1) [95% confidence interval, 0.03-1.52]; P = 0.04) with CPAP as compared with placebo. Additionally, norepinephrine levels and 24-hour blood pressure were reduced with CPAP as compared with placebo.

CONCLUSIONS

In patients with prediabetes, 8-hour nightly CPAP treatment for 2 weeks improves glucose metabolism compared with placebo. Thus, CPAP treatment may be beneficial for metabolic risk reduction. Clinical trial registered with www.clinicaltrials.gov (NCT 01156116).

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.

Established vascular effects of continuous positive airway pressure therapy in patients with obstructive sleep apnoea-an update

The aim of this review was to summarize the current data from randomised controlled trials (RCTs) on vascular effects of continuous positive airway pressure (CPAP) therapy in patients with obstructive sleep apnoea (OSA). There is good evidence from RCTs that CPAP lowers blood pressure (BP) to a clinically significant amount. The effect seems to be dependent on the hours of nightly CPAP usage. Data from RCTs have also proven a beneficial effect of CPAP on measures of vascular function such as endothelial function and arterial stiffness. However, there is still a lack of evidence from RCTs proving that CPAP reduces vascular events and mortality.

Positive airway pressure and electrical stimulation methods for obstructive sleep apnea treatment: a patent review (2005 - 2014)

INTRODUCTION

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a major health problem with significant negative effects on the health and quality of life. Continuous positive airway pressure (CPAP) is currently the primary treatment option and it is considered the most effective therapy for OSAHS. Nevertheless, comfort issues due to improper fit to patient's changing needs and breathing gas leakage limit the patient's adherence to treatment.

AREAS COVERED

The present patent review describes recent innovations in the treatment of OSAHS related to optimization of the positive pressure delivered to the patient, methods and systems for continuous self-adjusting pressure during inspiration and expiration phases, and techniques for electrical stimulation of nerves and muscles responsible for the airway patency.

EXPERT OPINION

In the last few years, CPAP-related inventions have mainly focused on obtaining an optimal self-adjusting pressure according to patient's needs. Despite intensive research carried out, treatment compliance is still a major issue. Hypoglossal electrical nerve stimulation could be an effective secondary treatment option when CPAP primary therapy fails. Several patents have been granted focused on selective stimulation techniques and parameter optimization of the stimulating pulse waveform. Nevertheless, there remain important issues to address, like effectiveness and adverse events due to improper stimulation.

Obstructive sleep apnea: acute effects of CPAP on polyssonographic variables

Introduction The use of non-invasive ventilation in the form of continuous positive airway pressure (CPAP) is among the main therapeutic options for patients with obstructive sleep apnea (OSA). Yet the effects of CPAP obtained on the first night of use are underreported. Objective To evaluate the acute effects of CPAP on polysomnographic variables in patients with OSA. Materials and methods This study is a case series with 31 patients (55.8 ± 11.4 years; 22 men) in the initial phase of CPAP treatment. The subjects were evaluated by means of polysomnography with and without CPAP (10.2 ± 3.1 cmH2O) and without CPAP, on different days, by means of the following variables: sleep stages 1, 2 and 3 (N1, N2 and N3), rapid eye movement (REM) sleep, apnea and hypopnea index (AHI), AHI in REM sleep (AHIREM) and the micro-arousal index (MAI). Results The use of CPAP resulted in a reduction of N2 (p < 0.001), AHI (p < 0.001), AHIREM (p < 0.001) and MAI (p = 0.001). There was an increase in N3 (p = 0.006) and REM sleep (p < 0.001) during the night with use of CPAP. Conclusion This study demonstrated that, from the first night of use by patients with OSA, CPAP promotes greater balance between sleep phases, and improves sleep quality. These results should be presented to patients and their families in order to encourage greater adherence in the initial phase of treatment with CPAP.

On the cutting edge of obstructive sleep apnoea: where next?

Obstructive sleep apnoea is a common disease that is now more widely recognised because of the rise in prevalence and the increasingly compelling data that shows major neurocognitive and cardiovascular sequelae. At the same time, the clinical practice of sleep medicine is changing rapidly, with novel diagnostics and treatments that have established a home-based (rather than laboratory-based) management approach. We review the most recent insights and discoveries in obstructive sleep apnoea, with a focus on diagnostics and therapeutics. As will be discussed, management of obstructive sleep apnoea could soon transition from a so-called one size fits all approach to an individualised approach.

NuMoM2b Sleep-Disordered Breathing study: objectives and methods

OBJECTIVE

The objective of the Sleep Disordered Breathing substudy of the Nulliparous Pregnancy Outcomes Study Monitoring Mothers-to-be (nuMoM2b) is to determine whether sleep disordered breathing during pregnancy is a risk factor for adverse pregnancy outcomes.

STUDY DESIGN

NuMoM2b is a prospective cohort study of 10,037 nulliparous women with singleton gestations that was conducted across 8 sites with a central Data Coordinating and Analysis Center. The Sleep Disordered Breathing substudy recruited 3702 women from the cohort to undergo objective, overnight in-home assessments of sleep disordered breathing. A standardized level 3 home sleep test was performed between 6(0)-15(0) weeks' gestation (visit 1) and again between 22(0)-31(0) weeks' gestation (visit 3). Scoring of tests was conducted by a central Sleep Reading Center. Participants and their health care providers were notified if test results met "urgent referral" criteria that were based on threshold levels of apnea hypopnea indices, oxygen saturation levels, or electrocardiogram abnormalities but were not notified of test results otherwise. The primary pregnancy outcomes to be analyzed in relation to maternal sleep disordered breathing are preeclampsia, gestational hypertension, gestational diabetes mellitus, fetal growth restriction, and preterm birth.

RESULTS

Objective data were obtained at visit 1 on 3261 women, which was 88.1% of the studies that were attempted and at visit 3 on 2511 women, which was 87.6% of the studies that were attempted. Basic characteristics of the substudy cohort are reported in this methods article.

CONCLUSION

The substudy was designed to address important questions regarding the relationship of sleep-disordered breathing on the risk of preeclampsia and other outcomes of relevance to maternal and child health.

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.

Obstructive sleep apnea as a risk factor for type 2 diabetes mellitus

Obstructive sleep apnea (OSA) is independently associated with cardiovascular and cardiometabolic risk in several large epidemiologic studies. OSA leads to several physiologic disturbances such as intermittent hypoxia, sleep fragmentation, and increase in autonomic tone. These disturbances have been associated with insulin resistance and type 2 diabetes mellitus (T2DM) in animal and human studies. Studies also suggest a bidirectional relationship between OSA and T2DM whereby T2DM itself might contribute to the features of OSA. Moreover, successful treatment of OSA may reduce these risks, although this is controversial. The purpose of this article is to review 1) the links and bidirectional associations between OSA and T2DM; 2) the pathogenic mechanisms that might link these two disease states; 3) the role of continuous positive airway pressure therapy in improving glucose tolerance, sensitivity, and resistance; and 4) the implications for clinical practice.

Engineering sleep disorders: from classical CPAP devices toward new intelligent adaptive ventilatory therapy

Among the most common sleep disorders are those related to disruptions in airflow (apnea) or reductions in the breath amplitude (hypopnea) with or without obstruction of the upper airway (UA). One of the most important sleep disorders is obstructive sleep apnea (OSA). This sleep-?disordered breathing, quantified by the apnea??hypopnea index (AHI), can produce a significant reduction of oxygen saturation and an abnormal elevation of carbon dioxide levels in the blood. Apnea and hypopnea episodes are associated with arousals and sleep fragmentation during the night and compensatory response of the autonomic nervous system.

Psychometric performance and responsiveness of the functional outcomes of sleep questionnaire and sleep apnea quality of life instrument in a randomized trial: the HomePAP study

STUDY OBJECTIVES

Measures of health-related quality of life (HRQL) specific for sleep disorders have had limited psychometric evaluation in the context of randomized controlled trials (RCTs). We investigated the psychometric properties of the Functional Outcomes of Sleep Questionnaire (FOSQ) and Sleep Apnea Quality of Life Instrument (SAQLI). We evaluated the FOSQ and SAQLI construct and criterion validity, determined a minimally important difference, and assessed for associations of responsiveness to baseline subject characteristics and continuous positive airway pressure (CPAP) adherence in a RCT population.

DESIGN

Secondary analysis of data collected in a multisite RCT of home versus laboratory-based diagnosis and treatment of obstructive sleep apnea (HomePAP trial).

PARTICIPANTS

Individuals enrolled in the HomePAP trial (n = 335).

INTERVENTIONS

N/A.

MEASUREMENT AND RESULTS

The FOSQ and SAQLI subscores demonstrated high reliability and criterion validity, correlating with Medical Outcomes Study 36-Item Short Form Survey domains. Correlations were weaker with the Epworth Sleepiness Scale (ESS). Both the FOSQ and SAQLI scores improved after 3 mo with CPAP therapy. Averaging 4 h or more of CPAP use was associated with an increase in the FOSQ beyond the minimally important difference. Baseline depressive symptoms and sleepiness predicted FOSQ and SAQLI responsiveness; demographic, objective obstructive sleep apnea (OSA) severity and sleep habits were not predictive in linear regression.

CONCLUSIONS

The FOSQ and SAQLI are responsive to CPAP intervention, with the FOSQ being more sensitive to differences in CPAP adherence than the SAQLI. These instruments provide unique information about health outcomes beyond that provided by changes in physiological measures of OSA severity (apnea-hypopnea index).

CLINICAL TRIAL INFORMATION

Portable Monitoring for Diagnosis and Management of Sleep Apnea (HomePAP) URL: http://clinicaltrials.gov/show/NCT00642486. NIH clinical trials registry number: NCT00642486.

Quality of life among untreated sleep apnea patients compared with the general population and changes after treatment with positive airway pressure

Obstructive sleep apnea leads to recurrent arousals from sleep, oxygen desaturations, daytime sleepiness and fatigue. This can have an adverse impact on quality of life. The aims of this study were to compare: (i) quality of life between the general population and untreated patients with obstructive sleep apnea; and (ii) changes of quality of life among patients with obstructive sleep apnea after 2 years of positive airway pressure treatment between adherent patients and non-users. Propensity score methodologies were used in order to minimize selection bias and strengthen causal inferences. The enrolled obstructive sleep apnea subjects (n = 822) were newly diagnosed with moderate to severe obstructive sleep apnea who were starting positive airway pressure treatment, and the general population subjects (n = 742) were randomly selected Icelanders. The Short Form 12 was used to measure quality of life. Untreated patients with obstructive sleep apnea had a worse quality of life when compared with the general population. This effect remained significant after using propensity scores to select samples, balanced with regard to age, body mass index, gender, smoking, diabetes, hypertension and cardiovascular disease. We did not find significant overall differences between full and non-users of positive airway pressure in improvement of quality of life from baseline to follow-up. However, there was a trend towards more improvement in physical quality of life for positive airway pressure-adherent patients, and the most obese subjects improved their physical quality of life more. The results suggest that co-morbidities of obstructive sleep apnea, such as obesity, insomnia and daytime sleepiness, have a great effect on life qualities and need to be taken into account and addressed with additional interventions.

Does race-ethnicity moderate the relationship between CPAP adherence and functional outcomes of sleep in US veterans with obstructive sleep apnea syndrome?

BACKGROUND

Little is known about the association of race-ethnicity and the relationship of continuous positive airway pressure (CPAP) adherence with functional outcomes of sleep in American samples with obstructive sleep apnea syndrome (OSAS). This retrospective study examines whether race-ethnicity moderates the relationship between CPAP adherence and functional outcomes of sleep in OSAS.

METHODS

Over 4 months, consecutive OSAS patients had CPAP data downloads and completed questionnaires (demographics, Functional Outcomes of Sleep Questionnaire [FOSQ], Epworth Sleepiness Scale [ESS], Insomnia Severity Index [ISI]) at the Miami VA sleep center. Medical diagnoses and polysomnography data were obtained from medical record. CPAP adherence was measured as mean daily hours of use. Hierarchical regression modeling was used to explore the differential impact of race-ethnicity and CPAP adherence on functional outcomes of sleep.

RESULTS

Two hundred twenty-seven veterans (93% male, age 59 ± 11 years) were included; 142 (63%) participants self-reported as white or Hispanic, and 85 participants (37%) as black. Hierarchical regression analyses failed to show main effects for race-ethnicity or CPAP use and FOSQ scores; however, the interaction of race-ethnicity with CPAP adherence was significantly associated with the total FOSQ (p = 0.04), Social (p = 0.02), and Intimacy (p = 0.01) subscale scores. For blacks, in adjusted analyses, CPAP adherence was positively associated with Social and Intimacy FOSQ subscales; however, no significant relationship was noted between CPAP use and FOSQ scores in whites/Hispanics.

CONCLUSIONS

Race-ethnicity may moderate the relationship between CPAP adherence and some functional outcomes of sleep; however, further studies are needed.

Consensus & evidence-based INOSA Guidelines 2014 (first edition)

Obstructive sleep apnoea (OSA) and obstructive sleep apnoea syndrome (OSAS) are subsets of sleep-disordered breathing. Awareness about OSA and its consequences amongst the general public as well as the majority of primary care physcians across India is poor. This necessiated the development of the INdian initiative on Obstructive sleep apnoea (INOSA) guidelines under the auspices of Department of Health Research, Ministry of Health & Family Welfare, Government of India. OSA is the occurrence of an average five or more episodes of obstructive respiratory events per hour of sleep with either sleep related symptoms or co-morbidities or ≥ 15 such episodes without any sleep related symptoms or co-morbidities. OSAS is defined as OSA associated with daytime symptoms, most often excessive sleepiness. Patients undergoing routine health check-up with snoring, daytime sleepiness, obesity, hypertension, motor vehicular accidents and high risk cases should undergo a comprehensive sleep evaluation. Medical examiners evaluating drivers, air pilots, railway drivers and heavy machinery workers should be educated about OSA and should comprehensively evaluate applicants for OSA. Those suspected to have OSA on comprehensive sleep evaluation should be referred for a sleep study. Supervised overnight polysomnography (PSG) is the "gold standard" for evaluation of OSA. Positive airway pressure (PAP) therapy is the mainstay of treatment of OSA. Oral appliances are indicated for use in patients with mild to moderate OSA who prefer oral appliances to PAP, or who do not respond to PAP or who fail treatment attempts with PAP or behavioural measures. Surgical treatment is recommended in patients who have failed or are intolerant to PAP therapy.

Coenzyme Q10 benefits symptoms in Gulf War veterans: results of a randomized double-blind study

We sought to assess whether coenzyme Q10 (CoQ10) benefits the chronic multisymptom problems that affect one-quarter to one-third of 1990-1 Gulf War veterans, using a randomized, double-blind, placebo-controlled study. Participants were 46 veterans meeting Kansas and Centers for Disease Control criteria for Gulf War illness. Intervention was PharmaNord (Denmark) CoQ10 100 mg per day (Q100), 300 mg per day (Q300), or an identical-appearing placebo for 3.5 ± 0.5 months. General self-rated health (GSRH), the primary outcome, differed across randomization arms at baseline, and sex significantly predicted GSRH change, compelling adjustment for baseline GSRH and prompting sex-stratified analysis. GSRH showed no significant benefit in the combined-sex sample. Among males (85% of participants), Q100 significantly benefited GSRH versus placebo and versus Q300, providing emphasis on Q100. Physical function (summary performance score, SPS) improved on Q100 versus placebo. A rise in CoQ10 approached significance as a predictor of improvement in GSRH and significantly predicted SPS improvement. Among 20 symptoms each present in half or more of the enrolled veterans, direction-of-difference on Q100 versus placebo was favorable for all except sleep problems; sign test 19:1, p=0.00004) with several symptoms individually significant. Significance for these symptoms despite the small sample underscores large effect sizes, and an apparent relation of key outcomes to CoQ10 change increases prospects for causality. In conclusion, Q100 conferred benefit to physical function and symptoms in veterans with Gulf War illness. Examination in a larger sample is warranted, and findings from this study can inform the conduct of a larger trial.

Home-based diagnosis of obstructive sleep apnea in an urban population

STUDY OBJECTIVES

Home-based diagnosis of obstructive sleep apnea (OSA) with portable monitoring (PM) is increasingly utilized, but remains understudied in underserved and minority populations. We tested the feasibility of home PM in an urban population at risk for OSA compared to in-laboratory polysomnography (PSG) and examined patient preference with respect to home PM versus PSG.

METHODS

Randomized crossover study of home PM (WatchPAT200) and in-laboratory simultaneous PSG and PM in 75 urban African Americans with high pre-test probability of OSA, identified with the Berlin questionnaire.

RESULTS

Fifty-seven of 75 participants were women, average age 45 ± 11 years (mean ± SD), 35% with ≤ high school education, and 76% with annual household income < $50,000. Technical failure rates were 5.3% for home vs. 3.1% for in-laboratory PM. There was good agreement between apnea hypopnea index on PSG; AHIPSG and AHI on home PM (mean ± 2 SD of the differences = 0.64 ± 46.5 and intraclass correlation coefficient; ICC = 0.73). The areas under the curve for the receiver-operator characteristic curves for home PM were 0.90 for AHIPSG ≥ 5, 0.95 for AHIPSG ≥ 10, and 0.92 for AHIPSG ≥ 15. 62/75 (82%) participants preferred home over in-laboratory testing.

CONCLUSIONS

Home PM for diagnosis of OSA in a high risk urban population is feasible, accurate, and preferred by patients. As home PM may improve access to care, the cost-effectiveness of this diagnostic strategy for OSA should be examined in underserved urban and rural populations.

CLINICAL TRIALS REGISTRATION

ClinicalTrials.gov, identifier: NCT01997723.

Half of the family members of critically ill patients experience excessive daytime sleepiness

BACKGROUND

Sleepiness and fatigue are commonly reported by family members of intensive care unit (ICU) patients. Sleep deprivation may result in cognitive deficits. Sleep deprivation and cognitive blunting have not been quantitatively assessed in this population. We sought to determine the proportion of family members of ICU patients that experience excessive daytime sleepiness, sleep-associated functional impairment, and cognitive blunting.

METHODS

Multicenter, cross-sectional survey of family members of patients admitted to ICUs at the University of Maryland Medical Center, Johns Hopkins University Hospital, and Christiana Hospital. Family members of ICU patients were evaluated using the Epworth Sleepiness Scale, a validated survey assessing sleepiness in everyday situations (normal, less than 10); the Functional Outcomes of Sleep Questionnaire-10 (FOSQ-10), a questionnaire quantifying the impact of sleepiness on daily activities (normal, at least 17.9); and psychomotor vigilance testing, a test of cognitive function, in relation to sleep deprivation (normal mean reaction time less than 500 ms).

RESULTS

A total of 225 family members were assessed. Of these, 50.2 % (113/225) had Epworth scores consistent with excessive daytime sleepiness. Those with sleepiness experienced greater impairment in performing daily activities by FOSQ-10 (15.6 ± 3.0 vs 17.4 ± 2.2, p < 0.001). Cognitive blunting was found in 13.3 % (30/225) of family members and 15.1 % (14/93) of surrogate decision-makers. Similar rates of cognitive blunting as reported by mean reaction time of at least 500 ms were found among family members whether or not they reported sleepiness (15.0 % (17/113) vs. 11.6 % (13/112), p = 0.45).

CONCLUSIONS

Half of the family members of ICU patients suffer from excessive daytime sleepiness. This sleepiness is associated with functional impairment, but not cognitive blunting.

Home ventilation therapy in obstructive sleep apnea-hypopnea syndrome

Obstructive sleep apnea-hypopnea is a highly prevalent disease that is often underdiagnosed at present. It has a significant economic and social welfare impact, accounting for a large part of the resources assigned to home respiratory therapies. As part of the 2014 SEPAR Year of the Chronic Patient and Domiciliary Respiratory Care sponsored by the Spanish Society of Pulmonology and Thoracic Surgery, this article reviews the most recent publications on the indications and controversial issues in the treatment of sleep apnea, the latest evidence for indication of various positive pressure devices, and adjustment modes, ranging from the use of empirical formulae or mathematical estimations to modern auto-CPAP equipment, while not forgetting the gold standard of manual titration. Emphasis is placed on the need for monitoring required by patients to ensure treatment adherence and compliance. Finally, other therapies that are not the object of this article are briefly reviewed.

A crossover randomised controlled trial of oral mandibular advancement devices for obstructive sleep apnoea-hypopnoea (TOMADO)

RATIONALE

Mandibular advancement devices (MADs) are used to treat obstructive sleep apnoea-hypopnoea syndrome (OSAHS) but evidence is lacking regarding their clinical and cost-effectiveness in less severe disease.

OBJECTIVES

To compare clinical- and cost-effectiveness of a range of MADs against no treatment in mild to moderate OSAHS.

MEASUREMENTS AND METHODS

This open-label, randomised, controlled, crossover trial was undertaken at a UK sleep centre. Adults with Apnoea-Hypopnoea Index (AHI) 5-<30/h and Epworth Sleepiness Scale (ESS) score ≥9 underwent 6 weeks of treatment with three non-adjustable MADs: self-moulded (SleepPro 1; SP1); semi-bespoke (SleepPro 2; SP2); fully-bespoke MAD (bMAD); and 4 weeks no treatment. Primary outcome was AHI scored by a polysomnographer blinded to treatment. Secondary outcomes included ESS, quality of life, resource use and cost.

MAIN RESULTS

90 patients were randomised and 83 were analysed. All devices reduced AHI compared with no treatment by 26% (95% CI 11% to 38%, p=0.001) for SP1, 33% (95% CI 24% to 41%) for SP2 and 36% (95% CI 24% to 45%, p<0.001) for bMAD. ESS was 1.51 (95% CI 0.73 to 2.29, p<0.001, SP1) to 2.37 (95% CI 1.53 to 3.22, p<0.001, bMAD) lower than no treatment (p<0.001 for all). Compliance was lower for SP1, which was the least preferred treatment at trial exit. All devices were cost-effective compared with no treatment at a £20,000/quality-adjusted life year (QALY) threshold. SP2 was the most cost-effective up to £39,800/QALY.

CONCLUSIONS

Non-adjustable MADs achieve clinically important improvements in mild to moderate OSAHS and are cost-effective. Of those trialled, the semi-bespoke MAD is an appropriate first choice.

TRIAL REGISTRATION NUMBER

ISRCTN02309506.

On treatment but still sleepy: cause and management of residual sleepiness in obstructive sleep apnea

PURPOSE OF REVIEW

Although continuous positive airway pressure (CPAP) treatment effectively reduces sleepiness in obstructive sleep apnea (OSA) patients, some patients remain sleepy in spite of proper treatment. After exclusion or treatment of known causes of sleepiness, residual sleepiness may be diagnosed. Recent changes in approval for currently available wakefulness stimulants in Europe, development of new stimulants and questions about the reality of residual sleepiness prompted this review.

RECENT FINDINGS

Prevalence of residual sleepiness is approximately 10% and clearly decreases with increased nightly use of CPAP. Before treatment, patients with residual sleepiness are younger, suffer from less severe OSA and have worse health perception and mood than patients who respond to CPAP. Residual sleepiness is accompanied by other residual symptoms (e.g. fatigue, poor quality of life), suggesting the existence of a 'CPAP resistant syndrome'. Pathophysiological mechanisms remain unclear. Stimulant medication may be beneficial in some patients and is well tolerated.

SUMMARY

In spite of a substantial prevalence, residual sleepiness remains still poorly understood and may be difficult to treat. There remains a need for large prospective studies to better define predictive baseline characteristics and further research on causal mechanisms and pharmacological treatments, including large, long-term clinical trials of wakefulness stimulants, is needed.

Obstructive sleep apnea: an unexpected cause of insulin resistance and diabetes

Obstructive sleep apnea (OSA) is prevalent with type 2 diabetes. Conversely, nondiabetic patients with OSA are at increased risk of developing insulin resistance and diabetes. These disorders independently contribute to increased cardiovascular and cerebrovascular morbidity and mortality. The pathophysiology of OSA may help explain these associations. Evidence demonstrates that treatment of OSA with continuous positive airway pressure may lead to improvement in insulin sensitivity, hemoglobin A1c, systemic hypertension, and other components of the metabolic syndrome. Recognizing and treating OSA in patients with insulin resistance or diabetes ameliorates OSA-related symptoms and improves cardiometabolic risk.