Relationship between obstructive sleep apnoea during rapid eye movement sleep and metabolic syndrome parameters in patients with type 2 diabetes mellitus.

PURPOSE: Sleep-disordered breathing (SDB) is associated with hypertension, poor glycemic control and dyslipidemia. Usually, apnoea events tend to be more prominent during rapid eye movement (REM) sleep than non-REM (NREM) sleep. We examined which SDB parameters are associated with blood pressure (BP), HbA1c and lipid profile in patients with type 2 diabetes (T2D). METHODS: A total of 185 patients with T2D who underwent polysomnography were analysed. Exclusion criteria were: the presence of pulmonary diseases, central sleep apnoea, treated SDB, or REM sleep < 30 min. To predict BP, HbA1c, and lipid profiles, we performed multiple linear regression analyses adjusted for known risk factors. Subsequently, we performed multivariable logistic regression analyses. RESULTS: Patient characteristics (mean ± standard deviation/median) were as follows: age 58.0 ± 11.8 years, body mass index 26.0 kg/m2 (24.1-28.9 kg/m2 ), systolic BP 134 ± 19 mmHg, mean BP 98 ± 14 mmHg, HbA1c 7.4% (6.8-8.4%), triglyceride 143 mg/dL (97-195 mg/dL), non-high density lipoprotein (non-HDL) cholesterol 143 mg/dL (120-163 mg/dL), REM-apnoea-hypopnea index (AHI) 35.1/h (21.1-53.1/h). The analyses revealed that REM-AHI was independently associated with systolic and mean BP, whereas NREM-AHI was not. A statistically significant association was not observed between REM-AHI and HbA1c or lipid profile. CONCLUSION: In patients with T2D, REM-AHI was associated with systolic and mean BP. The alteration of BP, associated with SDB during REM sleep, may be an important pathophysiological link between SDB and cardiovascular diseases.

Relationship between sleep disordered breathing and heart rate turbulence in non-obese subjects.

Heart rate turbulence (HRT) is regarded as a parameter of cardiac autonomic dysfunction. Several studies have suggested that patients with sleep disordered breathing (SDB) have an impaired HRT, which play a role in the relationship between SDB and risk of cardiovascular morbidity and mortality. However, the impact of SDB on HRT independent from obesity is still debatable. Data of eligible subjects who underwent sleep test and 24 h Holter electrocardiogram (ECG) recording from 2009-2012 were analyzed. HRT parameters, turbulence onset (TO), and turbulence slope (TS) in the 24 h recording, while awakening, and sleeping (TO-24 h, TO-awake, TO-sleep, TS-24 h, TS-awake, and TS-sleep, respectively) were compared across subjects with no-to-mild, moderate, and severe SDB. Univariable and multivariable regression analyses including TO or TS as a dependent variable were performed. Data from 41 subjects were evaluated. Compared with the no-to-mild and moderate SDB groups, in the severe SDB group, the TO-24 h and TO-awake were significantly greater, and the TS-24 h, TS-awake, and TS-sleep were significantly lower. In multivariable analyses, the apnea-hypopnea index (AHI) was correlated directly with TO-24 h (coefficient, 0.36; P = 0.03) and TO-awake (coefficient, 0.40; P = 0.01). SDB severity, as represented by AHI, is related to HRT impairments in non-obese subjects. SDB, independent from obesity, may affect cardiac autonomic dysfunction.

Craniofacial anatomical risk factors in men with obstructive sleep apnea and heart failure: a pilot study.

PURPOSE: Obstructive sleep apnea (OSA) is complicated with heart failure (HF); however, the reason for this is not well understood. Craniofacial anatomic risk factors may contribute to OSA pathogenesis in HF patients. However, there are no data about cephalometric findings among OSA patients with HF. METHODS: Consecutive patients with HF and OSA (defined as total apnea-hypopnea index (AHI) ≥15/h) were enrolled. As controls, OSA patients without HF but matching the test group in age, BMI, and obstructive AHI were also enrolled. RESULTS: Overall, 17 OSA patients with HF and 34 OSA patients without HF were compared. There are no significant differences in the characteristics or polysomnographic parameters between 2 groups. In the cephalometric findings, compared with patients without HF, patients with HF showed a significantly greater angle between the line SN to point "A" (SNA) and a longer inferior airway space and greater airway area. However, the tongue area of patients with HF was more than those without HF. CONCLUSIONS: The craniofacial structures of OSA patients with HF were different from those without HF. OSA patients with HF had an upper airway anatomy that is more likely to collapse when sleeping while recumbent, despite having a larger airway space.

Relationship between atrial conduction delay and obstructive sleep apnea.

Prolonged P-wave duration, indicating atrial conduction delay, is a marker of left atrial abnormality and is reported as a potent precursor of atrial fibrillation (AF). Several studies have shown that obstructive sleep apnea (OSA) is associated with AF. We evaluated the relationship between OSA and prolonged P-wave duration. Consecutive subjects who underwent overnight polysomnography and showed a normal sinus rhythm, had no history of AF or ischemic heart disease, and showed no evidence of heart failure were enrolled. Apnea-hypopnea index (AHI) is defined as the number of apnea and hypopnea events per hour of sleep. P-wave duration was determined on the basis of the mean duration of three consecutive beats in lead II from a digitally stored electrocardiogram. A total of 250 subjects (middle-aged, predominantly male, mildly obese, with a mean P-wave duration of 106 ms) were enrolled. In addition to age, male gender, body mass index (BMI), hypertension, dyslipidemia, and uric acid and creatinine levels, AHI (r = 0.56; P < 0.001) had significant univariable relationship with P-wave duration. Multivariate regression analysis showed that age, BMI, male gender, and AHI (partial correlation coefficient, 0.47; P < 0.001) were significantly independently correlated to P-wave duration. Severity of OSA is significantly associated with delayed atrial conduction time. Obstructive sleep apnea may lead to progression of atrial remodeling as an AF substrate.

Clinical outcomes of chronic heart failure patients with unsuppressed sleep apnea by positive airway pressure therapy.

Introduction: Heart failure (HF) is an advanced stage of cardiac disease and is associated with a high rate of mortality. Previous studies have shown that sleep apnea (SA) is associated with a poor prognosis in HF patients. Beneficial effects of PAP therapy that is effective on reducing SA on cardiovascular events, were not yet established. However, a large-scale clinical trial reported that patients with central SA (CSA) which was not effectively suppressed by continuous positive airway pressure (CPAP) revealed poor prognosis. We hypothesize that unsuppressed SA by CPAP is associated with negative consequences in patients with HF and SA, including either obstructive SA (OSA) or CSA. Methods: This was a retrospective observational study. Patients with stable HF, defined as left ventricular ejection fraction of ≤50%; New York Heart Association class ≥ II; and SA [apnea-hypopnea index (AHI) of ≥15/h on overnight polysomnography], treated with CPAP therapy for 1 month and performed sleep study with CPAP were enrolled. The patients were classified into two groups according to AHI on CPAP (suppressed group: residual AHI ≥ 15/h; and unsuppressed group: residual AHI < 15/h). The primary endpoint was a composite of all-cause death and hospitalization for HF. Results: Overall, data of 111 patients including 27 patients with unsuppressed SA, were analyzed. The cumulative event-free survival rates were lower in the unsuppressed group during a period of 36.6 months. A multivariate Cox proportional hazard model showed that the unsuppressed group was associated with an increased risk for clinical outcomes (hazard ratio 2.30, 95% confidence interval 1.21-4.38, p = 0.011). Conclusion: Our study suggested that in patients with HF and SA including either OSA or CSA, presence of unsuppressed SA even on CPAP was associated with worse prognosis as compared to those with suppressed SA by CPAP.

Cross-Sectional Relationship Between Atrial Conduction Delay and Arterial Stiffness in Patients with Obstructive Sleep Apnea.

Aim: Prolonged P-wave duration (PWD), which indicates atrial conduction delay, is a potent precursor of atrial fibrillation (AF) that may be induced by obstructive sleep apnea (OSA). The cardio-ankle vascular index (CAVI), which is an arterial stiffness parameter, is elevated in patients with OSA; moreover, an increased CAVI is associated with atrial conduction delay through left atrium enlargement in association with left ventricular diastolic dysfunction. We aimed to examine the relationship between the CAVI and PWD in patients with OSA. Methods: We included patients with a sinus rhythm who underwent overnight polysomnography. We measured the PWD and CAVI on standard 12-lead electrocardiograms; further, we analyzed the relationship between PWD and CAVI. Results: We analyzed data from 300 participants (men, 89.0%; mean age, 52.3 ± 13.1 years; and body mass index, 26.2 ± 3.9 kg/m2). The mean PWD was 104.4 ± 10.4 ms while the mean CAVI was 7.5 ± 1.5. PWD was significantly correlated with CAVI (r = 0.478, p < 0.001); additionally, PWD and CAVI were directly associated with OSA severity (p = 0.002 and p = 0.002, respectively). Multivariate regression analysis revealed an independent significant correlation of PWD and CAVI with OSA severity. Conclusion: In patients with OSA, an increase in arterial stiffness is associated with atrial conduction delay.

Aortic dissection is associated with intermittent hypoxia and re-oxygenation.

Aortic dissection is a life-threatening cardiovascular disease with high in-hospital mortality. However, the risk factors of aortic dissection have not been fully elucidated. Obstructive sleep apnea (OSA) has been increasingly recognized as an independent cardiovascular risk factor. Among the underlying mechanisms to explain the association between OSA and cardiovascular morbidity, previous studies reported that intermittent hypoxia and re-oxygenation (IHR) might induce cardiovascular diseases via atherosclerosis. However, little is known about an association between aortic dissection and IHR. The aims of the study were to investigate the prevalence of nocturnal IHR among patients with aortic dissection and compared with that in subjects without aortic dissection, and to investigate whether there is an independent association between aortic dissection and IHR. We enrolled 29 patients with aortic dissection and 59 control subjects. We performed sleep studies and compared the results between the groups. Frequency of IHR is expressed as 3% oxygen desaturation index (ODI). Multivariate analysis was performed to identify determinants of aortic dissection. The percentage of either moderate-to-severe IHR or severe IHR was significantly higher in the aortic dissection group (p = 0.04 and <0.001, respectively) than in the control group. The mean 3% ODI of patients with aortic dissection was significantly higher than that of control subjects (34.8 ± 23.1 and 19.0 ± 14.1, p = 0.003). In multivariate analysis, 3% ODI was significantly associated with aortic dissection (odds ratio 1.44; 95% confidence interval 1.08-1.91; p = 0.01). The present study showed the close association between aortic dissection and, IHR, a major component of OSA.

Association between Frequency of Central Respiratory Events and Clinical Outcomes in Heart Failure Patients with Sleep Apnea.

Heart failure (HF) is a progressive cardiac disorder associated with high mortality and morbidity. Previous studies have shown that sleep apnea (SA) is associated with a poor prognosis in HF patients. When HF coexists with SA, both central and obstructive respiratory events often occur. However, few studies have investigated the association between the frequency of central respiratory events coexisting with obstructive events and clinical outcomes in patients with HF and SA. This was a retrospective observational study. Patients with stable HF, defined as a left ventricular ejection fraction of ≤50%, New York Heart Association class ≥ II, and SA (apnea-hypopnea index of ≥15/h on overnight polysomnography) were enrolled. The primary endpoint was a composite of all-cause death and hospitalization for HF. Overall, 144 patients were enrolled. During a period of 23.4 ± 16 months, 45.8% of patients experienced the outcome. The cumulative event-free survival rates were higher in the central SA-predominant group. Multivariate analyses showed that a greater percentage of central respiratory events was associated with an increased risk of clinical outcomes. In patients with HF and SA, the frequency of central respiratory events was an independent factor for all-cause death and hospitalization for HF.

Factors Associated With the Improvement of Left Ventricular Systolic Function by Continuous Positive Airway Pressure Therapy in Patients With Heart Failure With Reduced Ejection Fraction and Obstructive Sleep Apnea.

Background: Obstructive sleep apnea (OSA) is a potential risk factor in cardiovascular diseases, including arrhythmia, coronary artery disease, and heart failure (HF). Continuous positive airway pressure (CPAP) therapy is an effective therapy for OSA and the underlying HF, partly through a 5-9% increase in the left ventricular ejection fraction (LVEF). However, the data on the factors associated with the efficacy of CPAP on LVEF in patients with HF complicated by OSA are scarce. This study aimed to investigate whether LVEF improves in patients with OSA and HF after 1 month of CPAP therapy, and to clarify which factors are associated with the degree of LVEF improvement. Method: This was a prospective, single-arm, open-label study. We enrolled moderate-to-severe patients with OSA and HF who were being followed up at the cardiovascular center of Toranomon Hospital (Tokyo, Japan). The parameters of sleep study and LVEF were assessed at the baseline and after 1 month of CPAP. The multivariate regression analyses, with changes in LVEF as a dependent variable, were performed to determine the factors that were associated with the degree of LVEF improvement. Results: We analyzed 55 consecutive patients with OSA and HF (mean age: 60.7 ± 12.2 years, mean LVEF value: 37.2 ± 9.8%). One month of CPAP treatment decreased the apnea-hypopnea index (AHI) from 45.3 ± 16.1 to 5.4 ± 4.1 per hour, and the LVEF improved from 37.2 ± 9.8 to 43.2 ± 11.7%. The multivariate regression analyses demonstrated that age and body mass index (BMI) were significant determinants of LVEF improvement. Conclusion: The LVEF improved significantly after 1 month of CPAP therapy in Japanese patients with OSA and HF. Multivariate regression analyses indicated that an improvement in LVEF was likely to be observed in young patients with obesity.

Sleep Apnea Syndrome (SAS) Clinical Practice Guidelines 2020.

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

Multimodal Telemonitoring for Weight Reduction in Patients With Sleep Apnea: A Randomized Controlled Trial.

BACKGROUND: Telemonitoring the use of CPAP devices and remote feedback on device data effectively optimizes CPAP adherence in patients with OSA. RESEARCH QUESTION: Can expanding the scope of telemonitoring and remote feedback to body weight (BW), BP, and physical activity enhance efforts for BW reduction in Patients with OSA receiving CPAP? STUDY DESIGN AND METHODS: Participants were recruited from patients at 16 sleep centers in Japan with OSA and obesity who were receiving CPAP therapy. Obesity was defined as a BMI of ≥ 25 kg/m2, based on Japanese obesity guidelines. Implementation of CPAP telemonitoring was enhanced with electronic scales, BP monitors, and pedometers that could transmit data from devices wirelessly. Participants were randomized to the multimodal telemonitoring group or the usual CPAP telemonitoring group and were followed up for 6 months. Attending physicians provided monthly telephone feedback calls to the usual CPAP telemonitoring group on CPAP data obtained remotely. In the multimodal telemonitoring group, physicians additionally encouraged participants to reduce their BW, after sharing the remotely obtained data on BW, BP, and step count. The primary outcome was set as ≥ 3% BW reduction from baseline. RESULTS: One hundred sixty-eight participants (BMI, 31.7 ± 4.9 kg/m2) completed the study, and ≥ 3% BW reduction occurred in 33 of 84 participants (39.3%) and 21 of 84 participants (25.0%) in the multimodal telemonitoring and usual CPAP telemonitoring groups, respectively (P = .047). Whereas no significant differences were found between the two groups in the change in office and home BP, daily step counts during the study period were significantly higher in the multimodal telemonitoring group than in the usual CPAP telemonitoring group (4,767 steps/d [interquartile range (IQR), 2,864-6,617 steps/d] vs 3,592 steps/d [IQR, 2,117-5,383 steps/d]; P = .02) INTERPRETATION: Multimodal telemonitoring may enhance BW reduction efforts in patients with OSA and obesity. TRIAL REGISTRY: UMIN Clinical Trials Registry; No.: UMIN000033607; URL: www.umin.ac.jp/ctr/index.htm.

Sleep Apnea Syndrome (SAS) Clinical Practice Guidelines 2020.

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

Effects of olmesartan on blood pressure and insulin resistance in hypertensive patients with sleep-disordered breathing.

The increased risk of cardiovascular morbidity and mortality among patients with sleep-disordered breathing (SDB) has been linked to arterial hypertension and insulin resistance. However, an effective antihypertensive agent for patients with SDB has not been identified. We investigated the effect of the angiotensin II subtype 1 receptor blocker olmesartan in hypertensive patients with SDB. This prospective, one-arm pilot study included 25 male patients with untreated SDB (mean age, 52.7 ± 11.4 years). We measured blood pressure, oxygen desaturation index (ODI), cardiac function using echocardiography, and insulin resistance using the homeostasis model assessment (HOMA) before and after 12 weeks of olmesartan therapy (mean dose, 17.6 ± 4.4 mg/day). Olmesartan significantly decreased systolic blood pressure (151.4 ± 8.0 vs. 134.0 ± 7.4 mmHg; P < 0.001), diastolic blood pressure (93.4 ± 7.1 vs. 83.9 ± 6.3 mmHg; P < 0.001), and HOMA index (3.7 ± 2.9 vs. 2.8 ± 1.9; P = 0.012). Furthermore, left ventricular ejection fraction significantly increased at 12 weeks (68.1 ± 5.1 vs. 71.6 ± 5.4%; P = 0.009). However, body mass index (BMI) and degree of SDB did not change (BMI, 26.6 ± 4.0 vs. 26.6 ± 4.2 kg/m2, P = 0.129; 3% ODI, 29.5 ± 23.1 vs. 28.2 ± 21.0 events/h, P = 0.394). Olmesartan significantly reduced blood pressure and insulin resistance in hypertensive patients with SDB without changing BMI or SDB severity.

Evaluation of the Apnea-Hypopnea Index Determined by Adaptive Servo-Ventilation Devices in Patients With Heart Failure and Sleep-Disordered Breathing.

Introduction: Adaptive servo-ventilation (ASV) devices are designed to suppress central respiratory events, and therefore effective for sleep-disordered breathing (SDB) in patients with heart failure (HF) and provide information about their residual respiratory events. However, whether the apnea-hypopnea index (AHI), determined by the ASV device AutoSet CS (ASC), correlates with the AHI calculated by polysomnography (PSG) in patients with HF and SDB remains to be evaluated. Methods: Consecutive patients with SDB titrated on ASC were included in the study. We assessed the correlation between AHI determined by manual scoring during PSG (AHI-PSG) and that determined by the ASC device (AHI-ASC) during an overnight session. Results: Thirty patients with HF and SDB (age, 68.8 ± 15.4 years; two women; left ventricular ejection fraction, 53.8 ± 17.9%) were included. The median AHI in the diagnostic study was 28.4 events/h, including both obstructive and central respiratory events. During the titration, ASC markedly suppressed the respiratory events (AHI-PSG, 3.3 events/h), while the median AHI-ASC was 12.8 events/h. We identified a modest correlation between AHI-PSG and AHI-ASC (r = 0.36, p = 0.048). The Brand-Altman plot indicated that the ASC device overestimated the AHI, and a moderate agreement was observed with PSG. Conclusions: There was only a modest correlation between AHI-PSG and AHI-ASC. The discrepancy may be explained by either the central respiratory events that occur during wakefulness or the other differences between PSG and ASC in the detected respiratory events. Therefore, clinicians should consider this divergence when assessing residual respiratory events using ASC.

Obstructive sleep apnea during rapid eye movement sleep in patients with diabetic kidney disease.

STUDY OBJECTIVES: Although recent studies suggest that obstructive sleep apnea during rapid eye movement (REM) is associated with different cardiometabolic and neurocognitive risks compared with non-REM (NREM) sleep, there is no information on whether obstructive sleep apnea during REM and/or NREM sleep is independently associated with diabetic kidney disease (DKD). METHODS: In this cross-sectional study, 303 patients with type 2 diabetes who were followed up at our diabetes outpatient clinic underwent all-night polysomnography. Logistic regression analysis was performed to determine the separate effects of obstructive sleep apnea during REM and/or NREM sleep (REM and/or NREM-apnea-hypopnea index [AHI]) and several other polysomnography parameters on DKD after adjustment for several known risk factors for DKD. RESULTS: The median (interquartile range) AHI, REM-AHI, and NREM-AHI of the patients (age 57.8 ± 11.8 years, male sex 86.8%, hypertension 64.3%, and DKD 35.2%) were 29.8 (18.0-45.4), 35.4 (21.1-53.3), and 29.1 (16.3-45.4) events/h, respectively. REM-AHI quartiles, but not NREM-AHI quartiles, correlated independently and significantly with DKD (P = .03 for linear trend, odds ratio (OR), and 95% confidence interval for Q2: 3.14 (1.10-8.98), Q3: 3.83 (1.26-11.60), Q4: 4.97 (1.60-15.46), compared with Q1). In addition, categorical AHI (P = .01, OR, and 95% confidence interval for ≥ 15 to < 30: 1.54 (0.64-3.71), ≥ 30: 3.08 (1.36-6.94) compared with < 15), quartiles of AHI (P = .01), quartiles of lowest arterial oxyhemoglobin saturation (P < .01), quartiles of percentage of time spent with arterial oxyhemoglobin saturation < 90 (P < .01), and quartiles of mean arterial oxyhemoglobin saturation were independently associated with DKD. CONCLUSIONS: Obstructive sleep apnea, especially during REM sleep, is a potential risk factor for DKD.

Aortic Knob Width as a Novel Indicator of Atherosclerosis and Obstructive Sleep Apnea.

AIM: Patients with obstructive sleep apnea (OSA) are likely to show increased arterial stiffness and progressive systemic atherosclerosis. Chest radiography reveals atherosclerotic changes in the aorta via measurement of aortic knob width. However, to our knowledge, aortic knob width in patients with OSA has never been evaluated. METHODS: We measured the aortic knob width in chest radiographs of 549 patients (age: 52.5±13.2 years; 69 women) who underwent overnight polysomnography. Moreover, we evaluated the association between aortic knob width and other clinical characteristics, including cardio-ankle vascular index (CAVI) and apnea-hypopnea index (AHI). Multivariate linear regression analysis was conducted to identify factors associated with aortic knob width. RESULTS: A significant direct correlation between aortic knob width and CAVI and between aortic knob width and AHI was observed. In multivariate linear regression analysis, either CAVI or AHI was independently associated with aortic knob width (p=0.004 and p＜0.001, respectively) in addition to age, male gender, body mass index, and systolic blood pressure. CONCLUSION: A significant independent correlation between aortic knob width and OSA severity was observed. Our findings suggest that an increase in the aortic knob width suggests atherosclerotic changes in the aorta and may be associated with OSA and increased arterial stiffness.

Association between Obstructive Sleep Apnea and SYNTAX Score.

Obstructive sleep apnea (OSA) is related to an increased risk of cardiovascular diseases, including coronary artery disease (CAD). We investigated the association between OSA and the severity of CAD by assessing coronary angiography findings. We retrospectively analyzed patients who underwent their first coronary angiography to evaluate CAD and polysomnography (PSG) to investigate the severity of OSA in our hospital from March 2002 to May 2015. The severity of CAD was determined based on coronary angiography findings using the SYNTAX score. The patients were divided into two groups according to the apnea-hypopnea index (AHI): mild OSA (AHI < 15/h) and moderate-to-severe OSA (AHI ≥ 15/h). Overall, 98 patients were enrolled. The SYNTAX score was significantly different between the two groups (p = 0.001). After adjustment for other risk factors, including age, sex, obesity, hypertension, hyperlipidemia, diabetes mellitus, smoking status, and family history of CAD, moderate-to-severe OSA significantly correlated to the SYNTAX score (partial correlations = 0.24, p = 0.039). These results suggest that the severity of CAD is related to moderate-to-severe OSA.

Clinical utility of a type 4 portable device for in-home screening of sleep disordered breathing.

BACKGROUND: Portable monitoring devices have been developed for in-home screening and to aid in the diagnosis of sleep disordered breathing (SDB) while increasing accessibility and reducing costs. Although there are many different devices available in the market, most have not undergone rigorous validation. Therefore, although such devices are promising, more research on their clinical utility is necessary. The purpose of this study was to assess the clinical utility of a type 4 home sleep apnea test (HSAT) as an in-home screening for SDB. METHODS: We investigated consecutive subjects who underwent in-laboratory overnight polysomnography following in-home screening using HSAT. We evaluated the correlation between apnea-hypopnea index (AHI) by in-laboratory overnight polysomnography and by HSAT and evaluated the sensitivity and specificity for AHI ≥5 and AHI ≥30 by the receiver operating characteristic (ROC) analysis. RESULTS: Finally, data of 387 participants (86.8% men, mean age 55.3±13.3 years and body mass index 25.1±4.1 kg/m2) were assessed. In all patients, AHI by HSAT correlated significantly with AHI by polysomnography (r=0.670, P<0.001). The area under curves of ROC for AHI ≥5 and AHI ≥30 were 0.854±0.029 and 0.841±0.022, respectively. The best cut-off of AHI by HSAT for detecting AHI by polysomnography ≥5 was 10.3 events/h (sensitivity, 82.8%; and specificity, 76.0%), and AHI by HSAT for detecting AHI by polysomnography ≥30 was 24.5 events/h (sensitivity, 75.8%; and specificity, 80.4%). CONCLUSIONS: This type 4 HSAT may have potential as a screening tool for SDB and thus have sufficient clinical utility.

A Randomized Controlled Trial of Telemedicine for Long-Term Sleep Apnea Continuous Positive Airway Pressure Management.

Rationale: The effects of telemedicine on adherence in patients with obstructive sleep apnea with long-term continuous positive airway pressure (CPAP) use have never been investigated.Objectives: To examine effects of a telemedicine intervention on adherence in long-term CPAP users.Methods: In a prospective, randomized, multicenter noninferiority trial conducted in 17 sleep centers across Japan, patients who had used CPAP for >3 months and were receiving face-to-face follow-up by physicians every 1 or 2 months were randomized by a coordinating center in a blind manner to the following three groups: 1) follow-up every 3 months accompanied by a monthly telemedicine intervention (telemedicine group: TM-group), 2) follow-up every 3 months (3-month group: 3M-group), or 3) monthly follow-up (1-month group: 1M-group). Each group was followed up for 6 months. The change in percentage of days with ≥4 h/night of CPAP use from baseline to the end of the study period was evaluated. A decline of ≥5% from baseline was considered deterioration of adherence. Noninferiority of TM- and 3M-groups compared with the 1M-group according to the number of patients with deterioration of adherence was evaluated with the Farrington and Manning test (noninferiority margin 15%).Results: A total of 483 patients were analyzed (median duration of CPAP use, 29 [interquartile range, 12-71] mo), and deterioration of adherence was found in 41 of 161 (25.5%), 55 of 166 (33.1%), and 35 of 156 (22.4%) patients in the TM-, 3M-, and 1M-groups, respectively. The noninferiority of the TM-group compared with the 1M-group was verified (difference in percentage of patients with adherence deterioration, 3.0%; 95% confidence interval [CI], -4.8% to 10.9%; P < 0.01). Conversely, the 3M-group did not show noninferiority to the 1M-group (percentage difference, 10.7%; 95% CI, 2.6% to 18.8%; P = 0.19). In the stratified analysis, adherence in TM- and 1M-group patients with poor adherence at baseline improved (TM: 45.8% ± 18.2% to 57.3% ± 24.4%; P < 0.01; 1M: 43.1% ± 18.5% to 53.6% ± 24.3%; P < 0.01), whereas that of the 3M-group did not (39.3% ± 20.8% to 39.8% ± 24.8%; P = 0.84).Conclusions: Intensive telemedicine support could help to optimize CPAP adherence even after long-term CPAP use.Clinical trial registered with www.umin.ac.jp/ctr/index.htm (trial number: UMIN000023118).