Role of obstructive sleep apnea in cardiovascular disease

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.

Clinical assessment and polysomnographic study of sleep apnea in a Chinese population of snorers

BACKGROUND AND OBJECTIVES

While an increasing number of people who snore are seeking medical consultations, the clinical characteristics of snorers are rarely reported. The aim of this study is to characterize the clinical and polysomnographic features in a population of snorers.

METHODS

A total of 490 subjects were examined retrospectively. The clinical history, Epworth Sleepiness Scale (ESS) scores, physical examination, and full-night polysomnography (PSG) data were obtained for all the subjects. The correlations between the neck circumference, waist circumference, ESS scores, body mass index (BMI), and apnea-hypopnea index (AHI) of obstructive sleep apnea (OSA) patients were explored. The gender and age differences in OSA patients were analyzed.

RESULTS

OSA was diagnosed in 84.7% of the sample, with 21.2% of the patients having a mild form, 15.4% having a moderate form, and 63.4% having a severe form of OSA. The ESS scores, neck circumference, waist circumference, and BMI were positively correlated with AHI in OSA patients. The ESS scores and BMI were negatively correlated with nadir oxygen saturation (SaO2). A greater number of men than women exhibited moderate to severe forms of the disease. OSA affects the work of males more commonly compared with females. Nocturia was a more common complaint in elderly OSA patients. Heart diseases coexisted more frequently with OSA in elderly patients.

CONCLUSIONS

In a population of snorers, OSA is the most common condition identified. The ESS scores and BMI were well correlated with the severity of the disease. Men had a more severe form of OSA than women. Nocturia frequently occurred in elderly OSA patients, as did the coexistence of heart disease.

The Association Between Obstructive Sleep Apnea and Nonarteritic Anterior Ischemic Optic Neuropathy: A Systematic Review and Meta-Analysis

PURPOSE

Nonarteritic anterior ischemic optic neuropathy (NAION) is a multifactorial disease, and recently epidemiologic studies have investigated the association between obstructive sleep apnea (OSA) and NAION. A systematic review of the association of OSA and NAION has not been performed. Therefore, the current meta-analysis was performed to assess such potential association between OSA and risk of NAION.

METHODS

A systematic search of PubMed and EMBASE databases was performed for published studies evaluating the association between OSA and NAION. The summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for categorical risk estimates. Sensitivity analyses and subgroup analyses were also performed to assess the robustness of pooled outcomes.

RESULTS

A total of four prospective cohort studies and one case-control study met our inclusion criteria. The pooled OR of developing NAION in the subjects with OSA was 6.18 (95% CI, 2.00-19.11) versus non-OSA controls. Sensitivity analyses showed that no matter one study excluded, the pooled OR did not change significantly, which indicated that the evidence was robust. In subgroup analyses, a significant association was seen in studies matched systemic risk factors (OR, 5.00; 95% CI, 2.22-11.25), but not in those non-matched. The magnitude and direction of effects were also affected by methodological variability, including study design, and diagnosis of OSA.

CONCLUSIONS

The findings from this meta-analysis supported the robust evidence that OSA was a strong independent risk factor of NAION. Relative to non-OSA controls, the subjects with OSA were found to have a more than sixfold risk of NAION. In future, more well-designed studies are needed to confirm these findings.

The role of nasal treatments in snoring and obstructive sleep apnoea

PURPOSE OF REVIEW

This review highlights recent advances and views on the role of the nose in snoring and obstructive sleep apnoea.

RECENT FINDINGS

Recent reviews and past randomized controlled trials generally agree that nasal surgery may improve quality of life in snoring and obstructive sleep apnoea. There have been no published randomized controlled trials regarding nasal treatments in snoring or obstructive sleep apnoea in the past year.

SUMMARY

Snoring and obstructive sleep apnoea are upper airway disorders in which the role of the nose has been well researched. Studies support that nasal surgery improves quality of life in snoring, but it may not lead to resolution of snoring. Likewise, nasal treatments for obstructive sleep apnoea increase the quality of life and treatment compliance in some patients. Further stratification of patients who may benefit from nasal intervention may clarify the role of nasal surgery.

Implantation of a defibrillator in a patient with an upper airway stimulation device

The patient is a 62-year-old man with continuous positive airway pressure-intolerant obstructive sleep apnea who was enrolled in a study for a hypoglossal nerve upper airway stimulation device (UAS). Nearly 2.5 years later, he was admitted to the hospital for unstable angina. Diagnostic workup revealed a prior myocardial infarction, an ejection fraction of 30% on maximal medical therapy, and episodes of nonsustained ventricular tachycardia. During hospitalization, the patient received an implantable cardioverter defibrillator (ICD). This is the first reported case of simultaneous use of a UAS and an ICD, and we report no untoward device interference between the two implantable devices.

The Effect of Adenotonsillectomy for Childhood Sleep Apnea on Cardiometabolic Measures

STUDY OBJECTIVES

Obstructive sleep apnea syndrome (OSAS) has been associated with cardiometabolic disease in adults. In children, this association is unclear. We evaluated the effect of early adenotonsillectomy (eAT) for treatment of OSAS on blood pressure, heart rate, lipids, glucose, insulin, and C-reactive protein. We also analyzed whether these parameters at baseline and changes at follow-up correlated with polysomnographic indices.

DESIGN

Data collected at baseline and 7-mo follow-up were analyzed from a randomized controlled trial, the Childhood Adenotonsillectomy Trial (CHAT).

SETTING

Clinical referral setting from multiple centers.

PARTICIPANTS

There were 464 children, ages 5 to 9.9 y with OSAS without severe hypoxemia.

INTERVENTIONS

Randomization to eAT or Watchful Waiting with Supportive Care (WWSC).

MEASUREMENTS AND RESULTS

There was no significant change of cardiometabolic parameters over the 7-mo interval in the eAT group compared to WWSC group. However, overnight heart rate was incrementally higher in association with baseline OSAS severity (average heart rate increase of 3 beats per minute [bpm] for apnea-hypopnea index [AHI] of 2 versus 10; [standard error = 0.60]). Each 5-unit improvement in AHI and 5 mmHg improvement in peak end-tidal CO2 were estimated to reduce heart rate by 1 and 1.5 bpm, respectively. An increase in N3 sleep also was associated with small reductions in systolic blood pressure percentile.

CONCLUSIONS

There is little variation in standard cardiometabolic parameters in children with obstructive sleep apnea syndrome (OSAS) but without severe hypoxemia at baseline or after intervention. Of all measures, overnight heart rate emerged as the most sensitive parameter of pediatric OSAS severity.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov (#NCT00560859).

Impact of inflammatory markers on the relationship between sleep quality and incident cardiovascular events in type 2 diabetes

AIMS

To analyze relevance of sleep quality with CVD in T2D patients and determine whether inflammation prompted by poor sleep has impact on the CVD.

METHODS

332 T2D patients were recruited and their sleep qualities were evaluated by PSQI. The patients with PSQI score >7 were in the poor sleep group, and the others were in the good sleep group. Plasma samples of the patients were obtained to measure inflammatory markers. Correlation analyses and regression analyses were performed to examine the cross-sectional relationships among the poor sleep, inflammatory markers and CVD.

RESULTS

The morbidity of CVD was significantly higher in the poor sleep patients compared to the good sleep patients (P=0.000). PSQI score ORs were both >1 for CVD in model 1 and model 2 (P<0.05). PSQI score were positively related to IL-6 and ICAM-1(P<0.05), negatively to FBI (P<0.05), but not related to CRP in linear regression models. Multiple logistic regression analysis showed IL-6 and ICAM-1, but not FBI and CRP, were related to CVD (P<0.05).

CONCLUSIONS

Poor sleep is regarded as a plausible risk factor for CVD in T2D patients, and may be mediated by certain inflammatory markers.

Comparison of Standard and Novel Signal Analysis Approaches to Obstructive Sleep Apnea Classification

Obstructive sleep apnea (OSA) is a disorder characterized by repeated pauses in breathing during sleep, which leads to deoxygenation and voiced chokes at the end of each episode. OSA is associated by daytime sleepiness and an increased risk of serious conditions such as cardiovascular disease, diabetes, and stroke. Between 2 and 7% of the adult population globally has OSA, but it is estimated that up to 90% of those are undiagnosed and untreated. Diagnosis of OSA requires expensive and cumbersome screening. Audio offers a potential non-contact alternative, particularly with the ubiquity of excellent signal processing on every phone. Previous studies have focused on the classification of snoring and apneic chokes. However, such approaches require accurate identification of events. This leads to limited accuracy and small study populations. In this work, we propose an alternative approach which uses multiscale entropy (MSE) coefficients presented to a classifier to identify disorder in vocal patterns indicative of sleep apnea. A database of 858 patients was used, the largest reported in this domain. Apneic choke, snore, and noise events encoded with speech analysis features were input into a linear classifier. Coefficients of MSE derived from the first 4 h of each recording were used to train and test a random forest to classify patients as apneic or not. Standard speech analysis approaches for event classification achieved an out-of-sample accuracy (Ac) of 76.9% with a sensitivity (Se) of 29.2% and a specificity (Sp) of 88.7% but high variance. For OSA severity classification, MSE provided an out-of-sample Ac of 79.9%, Se of 66.0%, and Sp = 88.8%. Including demographic information improved the MSE-based classification performance to Ac = 80.5%, Se = 69.2%, and Sp = 87.9%. These results indicate that audio recordings could be used in screening for OSA, but are generally under-sensitive.

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.

Robust spectral analysis of thoraco-abdominal motion and oxymetry in obstructive sleep apnea

The diagnosis of obstructive sleep apnea (OSA) relies on polysomnography (PSG), a multidimensional biosignal recording that is conducted in sleep laboratories. Standard PSG montage involves the use of nasal-oral airflow sensors to visualize cyclic episodes of upper airflow interruption, which are considered diagnostic of sleep apnea. Given the high-cost and discomfort associated with in-laboratory PSG, there is an emergent need for novel technology that simplifies OSA screening and diagnosis with less expensive methods. The main goal of this project was to identify novel OSA signatures based on the spectral analysis of thoraco-abdominal motion channels. Our main hypothesis was that proper spectral analysis can detect OSA cycles in adults using simultaneous recording of oxygen saturation (SaO2) and either, chest or abdominal motion. A sample study on 35 individuals was conducted with statistically significant results that suggest a strong relationship between airflow-independent signals and oxygen saturation. The impact of this new approach is that it may allow the design of more comfortable and reliable portable devices for screening, diagnosis and monitoring of OSA, functioning only with oximetry and airflow-independent (abdominal or chest) breathing sensors.

Urinary proteomic profiling in severe obesity and obstructive sleep apnoea with CPAP treatment

INTRODUCTION

Obstructive sleep apnoea (OSA) is common in obesity and is associated with cardiovascular and metabolic complications. Continuous positive airway pressure (CPAP) in OSA may lead to physiological changes reflected in the urinary proteome. The aim of this study was to characterise the urinary proteome in severely obese adult subjects with OSA who were receiving CPAP compared with severely obese subjects without OSA.

METHODS

Severely obese subjects with and without OSA were recruited. Subjects with OSA were receiving CPAP. Body composition and blood pressure measurements were recorded. Urinary samples were analysed by Capillary Electrophoresis-Mass Spectrometry (CE-MS).

RESULTS

Twenty-seven subjects with OSA-on-CPAP (age 49±7years, BMI 43±7 kg/m(2)) and 25 controls without OSA (age 52±9years, BMI 39±4 kg/m(2)) were studied. Age and BMI were not significantly different between groups. Mean CPAP use for OSA patients was 14.5±1.0 months. Metabolic syndrome was present in 14(52%) of those with OSA compared with 6(24%) of controls (p=0.039). A urinary proteome comprising 15 peptides was identified showing differential expression between the groups (p<0.01). Although correction for multiple testing did not reach significance, sequences were determined for 8 peptides demonstrating origins from collagens, fibrinogen beta chain and T-cadherin that may be associated with underlying cardiovascular disease mechanisms in OSA.

CONCLUSIONS

The urinary proteome is compared in OSA with CPAP and without OSA in severe obesity. The effects of CPAP on OSA may lead to changes in the urinary peptides but further research work is needed to investigate the potential role for urinary proteomics in characterising urinary peptide profiles in OSA.

Effect of CPAP on arterial stiffness in severely obese patients with obstructive sleep apnoea

BACKGROUND

Obstructive sleep apnoea (OSA) may independently increase cardiovascular risk in obesity. Although there is evidence that arterial stiffness is altered in OSA, knowledge of these effects with continuous positive airway pressure (CPAP) in severe obesity (body mass index (BMI) ≥ 35 kg/m(2)) is limited. This study aimed to explore how arterial stiffness, as measured by the augmentation index (Aix), changed in severely obese patients with OSA who were treated with CPAP and in patients without OSA.

METHODS

Forty-two patients with severe obesity-22 with OSA, 20 without OSA-were recruited at baseline and followed-up after a median of 13.5 months. Pulse wave analysis (PWA) was performed using applanation tonometry at the radial artery to measure augmentation index (Aix), augmentation pressure (AP) and subendocardial viability ratio (SEVR). Cardiovascular parameters and body composition were also measured.

RESULTS

There were significant improvements in Aix, AP (both P < 0.001) and SEVR (P = 0.021) in OSA patients on CPAP compared with subjects without OSA. Epworth scores (P < 0.001), systolic (P < 0.001) and mean arterial pressures (P = 0.002) improved with CPAP. Regression showed that CPAP was significantly associated with change in arterial stiffness from baseline. However, patients with OSA on CPAP continued to have increased arterial stiffness (Aix) (P < 0.001), AP (P = 0.028) and reduced SEVR (P = 0.002) relative to non-OSA patients.

CONCLUSION

Although sleepiness and blood pressure improve with CPAP in severe obesity, CPAP alone is not sufficient to modify PWA measures to levels comparable with non-OSA patients. This supports a need for a multifaceted approach when managing cardiovascular risk in patients with severe obesity and obstructive sleep apnoea receiving CPAP therapy.

[Beneficial effect of continuous positive airway pressure therapy in obstructive sleep apnea syndrome]

Continuous positive airway pressure therapy is an evidence based therapy of obstructive sleep apnea syndrome. The effective treatment of obstructive sleep apnea can decrease sympaticotonia and, consequently, blood pressure. Furthermore, it can improve inflammatory and metabolic parameters resulting in a decreased cardiovascular risk. This article summarizes the positive effects of continuous positive airway pressure therapy on cardiovascular risk factors in obstructive sleep apnea syndrome.

Urinary proteomics in obstructive sleep apnoea and obesity

BACKGROUND

Obstructive sleep apnoea (OSA) is a common complication of obesity and can have a substantial negative impact on a patient's quality of life and risk of cardiovascular disease. The aim of this case-control study was to undertake discovery profiling of urinary peptides using capillary electrophoresis-mass spectrometry (CE-MS) in obese subjects with and without OSA, without a history of coronary artery disease.

MATERIALS AND METHODS

Urinary samples were analysed by CE-MS. Body composition and blood pressure measurements were recorded. Overnight polysomnography was conducted to confirm or refute OSA. OSA patients were naïve to continuous positive airway pressure treatment.

RESULTS

Sixty-one subjects with OSA (age 47 ± 9 years, BMI 43 ± 8 kg/m(2)) and 31 controls (age 49 ± 10 years, BMI 40 ± 5 kg/m(2)) were studied; P = ns for age and BMI. Apnoea-hypopnoea Index was higher in patients with OSA (24 ± 18·6) than controls without OSA (non-OSA) (2·6 ± 1·1; P < 0·0001). Metabolic syndrome was present in 35 (57%) of those with OSA compared with 4 (13%) of controls (P < 0·0001). Twenty-four polypeptides were candidates for differential distribution (P < 0·01), although these differences did not reach significance after multiple testing. Sequences were determined for eight peptides demonstrating origins from collagens and fibrinogen alpha.

CONCLUSIONS

In this study, we report for the first time, urinary proteomic profile analyses using CE-MS in OSA and non-OSA obese groups. The differences in urinary proteomic profiles prior to adjustment for multiple testing, with increased metabolic syndrome in obese OSA subjects, suggest that there may be a role for CE-MS in characterising urinary profiles in severely obese populations with OSA.

Self-reported sleep bruxism and nocturnal gastroesophageal reflux disease in patients with obstructive sleep apnea: relationship to gender and ethnicity

STUDY OBJECTIVES

Nocturnal bruxism is associated with gastroesophageal reflux disease (GERD), and GERD is strongly associated with obstructive sleep apnea (OSA). Gender and ethnic differences in the prevalence and clinical presentation of these often overlapping sleep disorders have not been well documented. Our aim was to examine the associations between, and the symptoms associated with, nocturnal GERD and sleep bruxism in patients with OSA, and to examine the influence of gender and ethnicity.

METHODS

A retrospective chart review was performed of patients diagnosed with OSA at an academic sleep center. The patients completed a sleep questionnaire prior to undergoing polysomnography. Patients with confirmed OSA were evaluated based on gender and ethnicity. Associations were determined between sleep bruxism and nocturnal GERD, and daytime sleepiness, insomnia, restless legs symptoms, and markers of OSA severity in each group.

RESULTS

In these patients with OSA, the prevalence of nocturnal GERD (35%) and sleep bruxism (26%) were higher than the general population. Sleep bruxism was more common in Caucasians than in African Americans or Hispanics; there was no gender difference. Nocturnal GERD was similar among all gender and ethnic groups. Bruxism was associated with nocturnal GERD in females, restless legs symptoms in all subjects and in males, sleepiness in African Americans, and insomnia in Hispanics. Nocturnal GERD was associated with sleepiness in males and African Americans, insomnia in females, and restless legs symptoms in females and in Caucasians.

CONCLUSION

Patients with OSA commonly have comorbid sleep bruxism and nocturnal GERD, which may require separate treatment. Providers should be aware of differences in clinical presentation among different ethnic and gender groups.

Sleep-disordered breathing, type 2 diabetes and the metabolic syndrome

Sleep-disordered breathing (SDB) encompasses a spectrum of conditions that can lead to altered sleep homeostasis. In particular, obstructive sleep apnoea (OSA) is the most common form of SDB and is associated with adverse cardiometabolic manifestations including hypertension, metabolic syndrome and type 2 diabetes, ultimately increasing the risk of cardiovascular disease. The pathophysiological basis of these associations may relate to repeated intermittent hypoxia and fragmented sleep episodes that characterize OSA which drive further mechanisms with adverse metabolic and cardiovascular consequences. The associations of OSA with type 2 diabetes and the metabolic syndrome have been described in studies ranging from epidemiological and observational studies to controlled trials investigating the effects of OSA therapy with continuous positive airway pressure (CPAP). In recent years, there have been rising prevalence rates of diabetes and obesity worldwide. Given the established links between SDB (in particular OSA) with both conditions, understanding the potential influence of OSA on the components of the metabolic syndrome and diabetes and the underlying mechanisms by which such interactions may contribute to metabolic dysregulation are important in order to effectively and holistically manage patients with SDB, type 2 diabetes or the metabolic syndrome. In this article, we review the literature describing the associations, the possible underlying pathophysiological mechanisms linking these conditions and the effects of interventions including CPAP treatment and weight loss.

Age-group-specific associations between the severity of obstructive sleep apnea and relevant risk factors in male and female patients

Aim

To seek accurate and credible correlation manner between gender, age, and obesity; and the severity of obstructive sleep apnea (OSA) in large-scale population.

Methods

Totals of 1,975 male and 378 female OSA patients were sequentially recruited. Centralized covariant tendencies between age, body mass index (BMI), and waist hip ratio (WHR); and OSA severity, were explored in a gender-specific manner via multiple statistical analyses. The accuracies of observed correlations were further evaluated by adaptive multiple linear regression.

Results

All of age, BMI, WHR, smoking, drinking, and OSA severity differed between males and females. BMI and WHR were positively and (approximately) linearly associated with OSA severity in both males and females. Restricted cubic spline analysis was more effective than was the Pearson correlation approach in correlating age with AHI, and provided age crossover points allowing further piecewise linear modeling for both males and females. Multiple linear regression showed that increasing age was associated with OSA exacerbation in males aged ≤40 years and in females aged 45–53 years. BMI, WHR, and diabetes were independently associated with OSA severity in males with age-group-specific pattern. In females, only BMI was associated with OSA severity at all ages.

Conclusions

In male patients, BMI and WHR are prominent risk factors for OSA exacerbation. Age and diabetes are associated with OSA severity in males of particular ages. In females, BMI is also a prominent risk factor for severe OSA, and OSA severity increased with age in the range 45–53 years.

22q11.2 Deletion syndrome and obstructive sleep apnea

Otolaryngologic problems are common in the 22q11.2 deletion syndrome (DS) population. Structural anomalies and retrognathia may predispose these patients to obstructive sleep apnea (OSA). The current association of OSA in this population is not defined.

OBJECTIVE

(1) Define the frequency of OSA in 22q11.2 DS patients referred for polysomnography (PSG). (2) Determine if OSA is present before and/or after surgery to correct velopharyngeal insufficiency (VPI). (3) Determine effect of prior adenotonsillectomy on OSA following VPI surgery.

METHODS

Retrospective review of children treated from 2006 to 2013 in a tertiary care setting identified by ICD-9 758.32 (velocardiofacial syndrome) and 279.11 (DiGeorge syndrome). Surgical history and PSG data were abstracted from the identified records.

RESULTS

We identified 323 patients with 22q11.2 DS; 57 (18%) were screened at any point in care using PSG and 15 patients had PSG at multiple time points in care. In most cases, indication for PSG was sleep disordered breathing or pre-operative planning. Overall, 33 patients met criteria for OSA on PSG, accounting for 10.2% of our study population; however, the percentage of patients with OSA was significantly higher within the group of 57 patients (58%) who were screened with PSG. Twenty-one of the screened patients (54%) had PSG prior to any pharyngeal surgery and had mild to severe OSA (obstructive apnea/hypopnea index (AHI): median 5.1/h, range 1.9-25.6). Eighteen patients had PSG after adenotonsillectomy; 8 of these patients (44%) had mild to moderate OSA (median AHI 2.95/h, range 1.9-5.4). Seventeen patients had PSG after VPI surgery (palatopharyngeal flap (PPF) n=16, sphincteroplasty n=1). Nine of these patients (53%) had mild to severe OSA (median AHI 3/h, range 1.9-15). Patients who underwent adenotonsillectomy prior to VPI surgery had similar prevalence of OSA (50%, n=12) than those who did not (OSA: 60%, n=5, p=0.70). Most children had mild OSA.

CONCLUSION

Prevalence of OSA in this population of 22q11.2 DS patients is higher than expected in the general population. OSA risk is highest after VPI surgery, and may be decreased by adenotonsillectomy. Providers should have awareness of increased prevalence of OSA in patients with 22q11.2 DS. Close monitoring for OSA is warranted given the likelihood of subsequent surgical intervention that can worsen OSA.

Incidence and risk of atrial fibrillation in sleep-disordered breathing without coexistent systemic disease

BACKGROUND

Although the link between sleep-disordered breathing (SDB) and atrial fibrillation (AF) has been reported, a population-based longitudinal cohort study was lacking. The goal of the present study was to investigate the AF risk carried by SDB, using the National Health Insurance Research Database in Taiwan. METHODS AND RESULTS: From 2000 to 2001, a total of 579,521 patients who had no history of cardiac arrhythmias or significant comorbidities were identified. Among them, 4,082 subjects with the diagnosis of SDB were selected as the study group, and the remaining 575,439 subjects constituted the control group. The study endpoint was the occurrence of new-onset AF. During a follow-up of 9.2±2.0 years, there were 4,023 patients (0.7%) experiencing new-onset AF. The occurrence rate of AF was higher in patients with SDB compared to those without it (1.3% vs. 0.7%, P<0.001). The AF incidences were 1.38 and 0.76 per 1,000 person-years for patients with and without SDB, respectively. After anadjustment for age and sex, SDB was a significant risk factor of AF with a hazard ratio of 1.536. The AF risk increased with increasing clinical severity of SDB, represented by the requirement of continuous positive airway pressure use.

CONCLUSIONS

SDB itself, without the coexistence of other systemic diseases, was a risk factor of AF.

[What pathomechanisms can lead to stroke in obstructive sleep apnea?]

One of the less well-documented, potentially modifiable stroke risk factor is the obstructive sleep apnea. Obstructive sleep apnea increases cardiovascular morbidity and mortality, including stroke risk. The article summarizes the pathophysiological factors in sleep apnea syndrome which can increase stroke risk.

Addressing sleep disturbances: an opportunity to prevent cardiometabolic disease?

There is increasing awareness of the role of sleep disturbance as an important factor in health and disease. Although sub-clinical sleep disturbances (insufficient sleep duration or inadequate sleep quality) may be difficult to assess with conceptual and/or methodological clarity, this review attempts to summarize and synthesize these findings. First, the concept of sleep disturbance in a public health context is introduced, to provide context and rationale. Second, operational definitions of 'cardiometabolic disease' and 'sleep disturbance' are offered, to address many unclear operationalizations. Third, the extant literature is summarized regarding short or long sleep duration and/or insufficient sleep, insomnia and insomnia symptoms, general (non-specific sleep disturbances), circadian rhythm abnormalities that result in sleep disturbances, and, briefly, sleep-disordered breathing. Fourth, the review highlights the social/behavioural context of sleep, including discussions of sleep and race/ethnicity, socio-economic position, and other social/environmental factors, in order to place these findings in a social-environmental context relevant to public health. Fifth, the review highlights the issue of sleep as a domain of health behaviour and addresses issues regarding development of healthy sleep interventions. Finally, a research agenda of future directions is proposed.

High rates of obstructive sleep apnea symptoms among patients with schizophrenia

BACKGROUND

Patients with schizophrenia have high rates of obesity and cardiovascular morbidity, which are strongly associated with obstructive sleep apnea (OSA). The prevalence and risk factors for OSA are not well studied in patients with schizophrenia.

OBJECTIVE

The purpose of this study was to evaluate the frequency of OSA symptoms in a sample of outpatients with schizophrenia.

METHODS

This cross-sectional study was a secondary analysis of data generated from an insomnia study that evaluated 175 outpatients with schizophrenia or schizoaffective disorder in a single, large urban community mental health center. Results of scales evaluating insomnia were used to complete the STOP questionnaire, which is a screening tool for OSA validated in surgical populations. Appropriate statistical analysis was done to compare participants across groups.

RESULTS

Patients were classified into high risk for OSA (STOP ≥ 2) (57.7%), and low risk for OSA (STOP score < 2) (42.3%). We also identified patients with a known diagnosis of OSA (14.9%). Patients with diagnosed OSA had significantly higher STOP scores (mean 2.7 vs. 1.6 [t = 6.3; p < 0.001]). Only 23.8% of patients in the high-risk group were diagnosed with OSA. Body mass index was significantly higher in the diagnosed group (F[2,169] = 25; p < 0.001) as was diabetes (χ2 [2, N = 175] = 35, p < 0.001).

CONCLUSION

A large number of outpatients with severe mental illness are at high risk for OSA. The STOP questionnaire is easy to use and appears to have a very high clinical utility to detect OSA. Based on our findings, further studies are warranted to validate the tool in patients with severe mental illness.

Obstructive sleep apnea and the risk of atopic dermatitis: a population-based case control study

Background

Obstructive sleep apnea (OSA) is associated with systemic inflammation and induces various comorbid medical diseases. To date, no study has explored the relationship between OSA and atopic dermatitis (AD), an inflammatory and autoimmune skin disorder. This study investigated the longitudinal risk for AD in patients with OSA.

Methods

A random sample of 1,000,000 individuals from Taiwan's National Health Insurance database was collected. From this sample, 1222 patients with newly-diagnosed OSA between 2000 and 2005 were identified and compared with a matched cohort of 18330 patients without OSA. All patients were tracked for 5.5 years from the index date in order to identify which patients subsequently developed AD.

Results

During the 5.5-year follow-up period, the incidence rates of AD in the OSA cohort and comparison groups were 9.81 and 6.21 per 1000 person-years, respectively. After adjustment for age, gender, diabetes, hypertension, coronary heart disease, obesity, allergy, allergic rhinitis, asthma, monthly income, and geographic location, patients with OSA were 1.5-times more likely to develop AD than patients without OSA (95% CI = 1.15–1.95, p = 0.0025). The hazard risk for AD was greater in male OSA patients and young OSA patients (0–18 and 19–34 years), adjusted HRs being 1.53 (95% CI = 1.14–2.06, p = 0.005), 4.01(95% CI = 1.57–10.26, p = 0.0038) and 1.75(95% CI = 1.00–3.04, p = 0.0483), respectively. The log-rank test indicated that OSA patients <35-years-old had significantly higher cumulative incidence rates of AD than those patient of the same age in the comparison group (p = 0.0001).

Conclusion

Patients with OSA, especially male patients and younger patients, are at an increased risk for AD later in life.

Insomnia symptoms and subsequent cardiovascular medication: a register-linked follow-up study among middle-aged employees

Sleep disturbances have been associated with an increased risk of cardiovascular disease outcomes. The associations of insomnia with hypertension and dyslipidaemia, the main modifiable cardiovascular risk factors, are less studied. We especially lack understanding on the longitudinal effects of insomnia on dyslipidaemia. We aimed to examine the associations of insomnia symptoms with subsequent prescribed medication for hypertension and dyslipidaemia using objective register-based follow-up data. Baseline questionnaire surveys among 40-60-year-old employees of the City of Helsinki, Finland, were conducted in 2000-2002 (n = 6477, response rate 67%, 78% women) and linked to a national register on prescribed reimbursed medication 5-7 years prior to and 5 years after baseline. Associations between the frequency of insomnia symptoms (difficulties in initiating and maintaining sleep, non-restorative sleep) and hypertension and dyslipidaemia medication during the follow-up were analysed using logistic regression analysis (odds ratios with 95% confidence intervals). Analyses were adjusted for pre-baseline medication, sociodemographic and work-related factors, health behaviours, mental health, and diabetes. Frequent insomnia symptoms were reported by 20%. During the 5-year follow-up, 32% had hypertension medication and 15% dyslipidaemia medication. Adjusting for age, gender and pre-baseline medication, frequent insomnia symptoms were associated with hypertension medication (odds ratio 1.57, 95% confidence interval 1.23-2.00) and dyslipidaemia medication (odds ratio 1.59, 95% confidence interval 1.19-2.12). Occasional insomnia symptoms were also associated with cardiovascular medication, though less strongly. Further adjustments had negligible effects. To conclude, insomnia should be taken into account in the prevention and management of cardiovascular disease and related risk factors.

Sleep apnea headache: a growing concern in an increasingly obese population?

Sleep apnea headache is a recurrent universal pressing headache without accompanying symptoms at awakening that resolves within 4 h. The diagnosis requires polysomnography-verified apnea hypopnea index≥5, that is, obstructive sleep apnea (OSA). Morning headache has similar symptomatology without OSA. The prevalence of sleep apnea headache is 10-15% in people with OSA, whereas morning headache occurs in 5%. The severity of OSA only slightly affects the prevalence of sleep apnea headache. The pathophysiology of sleep apnea headache remains an enigma, since average oxygen desaturation and lowest oxygen saturation are similar in OSA people without sleep apnea headache. Migraine and tension-type headache are unrelated to OSA. Thus, growing concern of sleep apnea headache in an increasingly obese population is unfounded with our current knowledge.

Sleep symptoms, race/ethnicity, and socioeconomic position

STUDY OBJECTIVES

Growing evidence indicates sleep is a major public health issue. Race/ethnicity and socioeconomics may contribute to sleep problems. This study assessed whether sleep symptoms were more prevalent among minorities and/or the socioeconomically disadvantaged.

DESIGN

Cross-sectional.

SETTING

Epidemiologic survey.

PATIENTS OR PARTICIPANTS

2007-2008 National Health and Nutrition Examination Survey (N = 4,081).

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Sociodemographics included age, sex, race/ethnicity, marital status, and immigration. Socioeconomics included poverty, education, private insurance, and food insecurity. Sleep symptoms assessed were sleep latency > 30 min, difficulty falling asleep, sleep maintenance difficulties, early morning awakenings, non-restorative sleep, daytime sleepiness, snorting/gasping, and snoring. Decreased reported problems for most symptoms were found among minorities, immigrants, and lower education levels. In general, in fully adjusted models, long sleep latency was associated with female gender, being black/African American, lower education attainment, no private insurance, and food insecurity. Difficulty falling asleep, sleep maintenance difficulties, early morning awakenings, and non-restorative sleep were also associated with female gender and food insecurity. Daytime sleepiness was seen in female and divorced respondents. Snorting/gasping was more prevalent among male, other-Hispanic/Latino, and 9(th)- to 11(th)-grade-level respondents. Snoring was prevalent among male, other-Hispanic/Latino, less-educated, and food-insecure respondents.

CONCLUSIONS

Sleep symptoms were associated with multiple sociodemographic and economic factors, though these relationships differed by predictor and sleep outcome. Also, reports depended on question wording.

A multicenter evaluation of oral pressure therapy for the treatment of obstructive sleep apnea

OBJECTIVE

We aimed to evaluate the impact of a novel noninvasive oral pressure therapy (OPT) (Winx®, ApniCure) system on polysomnographic measures of sleep-disordered breathing, sleep architecture, and sleep stability in obstructive sleep apnea (OSA).

SUBJECTS AND METHODS

A 4-week, multicenter, prospective, open-label, randomized, crossover, first-night order of control vs treatment, single-arm trial was conducted in five American Academy of Sleep Medicine (AASM) - accredited sleep clinics and one research laboratory. Sixty-three subjects (analysis cohort) were studied from a screening cohort of 367 subjects. The analysis cohort was 69.8% men, ages 53.6±8.9 years (mean±SD), body mass index of 32.3±4.5kg/m(2), with mild to severe OSA. At treatment initiation, subjects received random assignment to one night with and one without (control) treatment, and they were assessed again following 28 nights of treatment. Breathing and sleep architecture were assessed each night based on blind scoring by a single centralized scorer using AASM criteria.

RESULTS

Average nightly usage across the take-home period was 6.0±1.4h. There were no severe or serious device-related adverse events (AEs). Median apnea-hypopnea index (AHI) was 27.5 events per hour on the control night, 13.4 events per hour on the first treatment night, and 14.8 events per hour after 28days of treatment. A clinically significant response (treatment AHI ⩽10/h and ⩽50% of control values) was seen in 20 of the 63 subjects evaluated. Rapid eye movement percentage (REM%) was significantly increased, and N1%, stage shifts to N1 sleep, overall stage shifts, total awakenings, and arousals per hour were all significantly reduced at both treatment nights compared to controls. Mean Epworth sleepiness scale (ESS) was significantly reduced from 12.1 to 8.6 (Cohen d effect size, 0.68) in those untreated for two or more weeks prior to OPT study participation and remained unchanged in subjects who directly switched from continuous positive airway pressure (CPAP) therapy to OPT.

CONCLUSION

Clinically significant improvements in sleep quality and continuity, AHI, ODI, ESS, and overall clinical status were achieved in an easily identified subgroup. OPT was safe and well-tolerated and nightly usage was high.

Screening for obstructive sleep apnoea in obesity and diabetes--potential for future approaches

BACKGROUND

It is recognised that sleep-disordered breathing (SDB), in particular, obstructive sleep apnoea (OSA) is associated with obesity and diabetes. The complications of OSA include dysregulation of metabolic and cardiovascular homeostasis. With the growing population of diabetes and obesity globally, it is becoming apparent that identifying and screening patients who are at risk is becoming increasingly crucial. Many patients may remain unaware of the potential diagnosis and continue to be undiagnosed. The high prevalence of OSA poses a demanding challenge to healthcare providers in order to provide sufficient resources and facilities for patient diagnosis and treatment.

DESIGN

In this article, we review the evidence in favour of screening populations deemed to be at increased risk of OSA, with particular reference to patients with obesity and diabetes. We consider the recent advances in potential screening methods that may allow new prognostic and predictive tools to be developed. A detailed search of Medline and Web of Science electronic databases for relevant articles in English was performed.

RESULTS

Apart from the use of screening tools such as questionnaires and clinical decision models, there is increasing evidence to suggest that there are differences in biological parameters in patients with OSA. Although further studies are required, there may be potential for such biomarkers to contribute to and augment the screening process. However, the significance of such biological tools remains to be elucidated.

CONCLUSIONS

A fundamental role for improved screening in patients with conditions such as obesity and diabetes can enable early interventions that may improve health outcomes relating to the adverse consequences of OSA. The future will see further research being carried out in the development of potential screening methods with emphasis on the selection of patients at risk of sleep disorders, thereby allowing more detailed physiological studies to be carried out where needed.

Physiological effects of obstructive sleep apnea syndrome in childhood

Sleep disordered breathing in children refers to a group of respiratory disorders that occur or are exacerbated during sleep. Obstructive sleep apnea syndrome (OSAS) is one of the most significant disorders in this group. OSAS can present in all age groups from early infancy to adolescent years. The cardinal feature of OSAS is limitation of inspiratory flow and volume during sleep resulting in abnormal gas exchange and/or alteration of sleep patterns. When OSAS is a chronic condition it often results in adverse physiological effects that impact on health and development. The present review discusses genesis of OSAS in children and consequent end organ injury with special emphasis on behavior and cognition, cardiovascular function, autonomic regulation, inflammation, endothelial function and metabolic syndrome.

Obstructive sleep apnoea and type 2 diabetes mellitus: a bidirectional association

Obstructive sleep apnoea and type 2 diabetes are common medical disorders that have important clinical, epidemiological, and public health implications. Research done in the past two decades indicates that obstructive sleep apnoea, through the effects of intermittent hypoxaemia and sleep fragmentation, could contribute independently to the development of insulin resistance, glucose intolerance, and type 2 diabetes. Conversely, type 2 diabetes might increase predisposition to, or accelerate progression of, obstructive and central sleep apnoea, possibly through the development of peripheral neuropathy and abnormalities of ventilatory and upper airway neural control. Although more research is needed to clarify the mechanisms underlying the bidirectional association between the two disorders, their frequent coexistence should prompt all health-care professionals to embrace clinical practices that include screening of a patient presenting with one disorder for the other. Early identification of obstructive sleep apnoea in patients with metabolic dysfunction, including type 2 diabetes, and assessment for metabolic abnormalities in those with obstructive sleep apnoea could reduce cardiovascular disease risk and improve the quality of life of patients with these chronic diseases.

Obstructive sleep apnea and coronary artery disease: from pathophysiology to clinical implications

Coronary artery disease (CAD) and obstructive sleep apnea (OSA) are both complex and significant clinical problems. The pathophysiological mechanisms that link OSA with CAD are complex and can influence the broad spectrum of conditions caused by CAD, from subclinical atherosclerosis to myocardial infarction. OSA remains a significant clinical problem among patients with CAD, and evidence suggesting its role as a risk factor for CAD is growing. Furthermore, increasing data support that CAD prognosis may be influenced by OSA and its treatment by continuous positive airway pressure (CPAP) therapy. However, stronger evidence is needed to definitely answer these questions. This paper focuses on the relationship between OSA and CAD from the pathophysiological effects of OSA in CAD, to the clinical implications of OSA and its treatment in CAD patients.

Sleep disordered breathing as a risk of cardiac events in subjects with diabetes mellitus and normal exercise echocardiographic findings

Sleep disordered breathing (SDB) is associated with type 2 diabetes mellitus (T2DM) and cardiovascular disease; however, the contribution of SDB to incident heart failure (HF), coronary artery disease (CAD), and atrial fibrillation (AF) in patients with T2DM is unknown. We followed up 834 consecutive asymptomatic patients with T2DM (age 56 ± 11 years, 369 women) with normal exercise echocardiographic findings for ≤8 years using electronic health records. The demographics, cardiac risk factors, symptoms, diagnoses, and medications were collected at the echocardiography and validated from the electronic health records. SDB was confirmed by a comprehensive sleep evaluation and/or polysomnography before echocardiography. SDB was diagnosed in 188 patients (21%) at baseline; 116 were untreated. During a median follow-up of 4.9 years (interquartile range 3.9 to 6.1), 22 congestive HF, 72 CAD, and 40 AF incident events were observed. In the Cox proportional hazards models, SDB was associated with incident CAD (hazard ratio 1.8, 95% confidence interval 1.1 to 3.0, p = 0.01; adjusted hazard ratio 1.9, 95% confidence interval 1.2 to 3.2, p <0.01) and AF (hazard ratio 2.6, 95% confidence interval 1.4 to 4.7, p = 0.01; adjusted hazard ratio 2.9, 95% confidence interval 1.5 to 5.9, p <0.01). Limiting SDB to only those patients diagnosed using polysomnography (n = 132), SDB was associated with incident CAD (hazard ratio 1.9, 95% confidence interval 1.1 to 3.3, p = 0.03; adjusted hazard ratio 2.2, 95% confidence interval 1.2 to 3.9, p = 0.01) and HF (hazard ratio 2.7, 95% confidence interval 1.1 to 7.0, p = 0.03; adjusted hazard ratio 3.5, 95% confidence interval 1.4 to 9.0, p <0.01). Female gender, age, elevated blood pressure, and left ventricular mass were additional correlates of CAD in those with asymptomatic T2DM. In conclusion, the association of SDB with incident CAD, AF, and HF in patients with T2DM justifies more liberal screening for SDB in patients with T2DM, realizing that SDB is a potentially modifiable risk factor.

Sleep-disordered breathing and cognition in older adults

Both sleep-disordered breathing (SDB) and cognitive impairment are common among older adults, yet few studies have examined their relationship within this population to determine whether the effect of SDB on cognition is of a magnitude similar to or greater than that observed in younger and middle-aged adults. Here, we review the extant literature and report that studies are largely supportive of an association between SDB and cognitive impairment in older adults, particularly in the domains of attention/vigilance, executive function, and verbal delayed recall memory. Presence of the APOE4 allele may confer increased vulnerability to SDB-associated cognitive dysfunction among elderly individuals. Although findings are mixed, there is strong evidence to suggest that SDB-related intermittent hypoxemia is the primary mechanism through which SDB exerts its adverse effects on cognition. We propose a microvascular model in which chronic intermittent hypoxemia causes vasculopathy that ultimately is expressed as cognitive impairment in the older adult. However, it remains unclear whether the effects of SDB on cognition are the same regardless of age or whether there is a synergistic interaction between age and SDB.

Patient perspective on use of an interactive website for sleep apnea

Incomplete patient adherence with nasal continuous positive airway pressure (CPAP) limits the effectiveness of treatment and results in suboptimal obstructive sleep apnea (OSA) outcomes. An interactive website specifically designed for patients with OSA was designed and utilized in a randomized clinical trial to test its effect on increasing CPAP adherence. The goal of this paper is to report on CPAP adherence, internet use, privacy concerns and user satisfaction in using the website. The original project was designed as a randomized, controlled clinical trial of Usual Care (UC, control) versus MyCPAP group (intervention). Questionnaires were administered to evaluate the patient perspective of using the MyCPAP website. Participation in the MyCPAP intervention resulted in higher CPAP adherence at the two-month time point relative to participation in the UC group (3.4  ±  2.4 and 4.1  ±  2.3 hrs/nt; P = 0.02; mean  ±  SD). Participants randomized to the MyCPAP website increased their use of the internet to obtain OSA related information, but did not increase their use of the internet to get information on general health or medical conditions. Users had very little concern about their CPAP data being viewed daily or being sent over the internet. Future studies should consider the use of newer evaluation criteria for collaborative adaptive interactive technologies.

Tae-eum type as an independent risk factor for obstructive sleep apnea

Obstructive sleep apnea (OSA) is prevalent and associated with several kinds of chronic diseases. There has been evidence that a specific type of Sasang constitution is a risk factor for metabolic and cardiovascular diseases that can be found in patients with OSA, but there are no studies that address the association between the Sasang constitution type (SCT) and OSA. The purpose of this study was to investigate the association between the SCT and OSA. A total of 652 participants were included. All participants were examined for demographic information, medical history, and completed an interviewer-administered questionnaire on life style and sleep-related variables. Biochemical analyses were performed to determine the glucose and lipid profiles. An objective recording of OSA was done with an unattended home PSG using an Embla portable device. The apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) were significantly higher in the Tae-eum (TE) type as compared to the So-eum (SE) and the So-yang (SY) types. Even after adjusting for confounding variables, the TE type still had a 2.34-fold (95% CI, 1.11–4.94; P = 0.0262) increased risk for OSA. This population-based cohort study found that the TE constitutional type is an independent risk factor for the development of OSA.

Preoperative screening and perioperative care of the patient with sleep-disordered breathing

PURPOSE OF REVIEW

Emerging data are raising concerns that patients with known or suspected obstructive sleep apnea (OSA) are at increased risk for a myriad of perioperative complications. Strategies to identify patients preoperatively with OSA, or at risk for OSA, are being advocated. In addition, approaches to identify patients most at risk for OSA-related postoperative complications have been described. While lacking solid evidence, a number of perioperative management strategies have been proposed for the care of these patients.

RECENT FINDINGS

Recent studies utilizing different methodologies have provided additional evidence regarding the impact that OSA can have on postoperative outcomes, including increased risk of difficult intubations, adverse pulmonary outcomes, and delirium. Tools, such as the STOP-Bang questionnaire and limited channel monitoring, have been investigated with regards to their utility to identify not only patients at risk for OSA but also those at risk for more severe OSA. Consensus-based guidelines for the perioperative care of OSA patients have recently been published.

SUMMARY

OSA is quite common in patients presenting for elective surgery and has been linked to increased perioperative complications. Attempts to identify these patients preoperatively appear prudent. Protocols on how best to manage these patients are available, although validation of their effectiveness is needed.

The Relationship between Obstructive Sleep Apnea and Atrial Fibrillation: A Complex Interplay

In recent years, growing evidence suggests an association between obstructive sleep apnea (OSA), a common sleep breathing disorder which is increasing in prevalence as the obesity epidemic surges, and atrial fibrillation (AF), the most common cardiac arrhythmia. AF is a costly public health problem increasing a patient's risk of stroke, heart failure, and all-cause mortality. It remains unclear whether the association is based on mutual risk factors, such as obesity and hypertension, or whether OSA is an independent risk factor and causative in nature. This paper explores the pathophysiology of OSA which may predispose to AF, clinical implications of stroke risk in this cohort who display overlapping disease processes, and targeted treatment strategies such as continuous positive airway pressure and AF ablation.