Obstructive sleep apnoea syndrome as a risk factor for hypertension: population study

Daytime napping and the risk of all-cause and cause-specific mortality: a 13-year follow-up of a British population

Epidemiologic studies have reported conflicting results on the relationship between daytime napping and mortality risk, and there are few data on the potential association in the British population. We investigated the associations between daytime napping and all-cause or cause-specific mortality in the European Prospective Investigation Into Cancer-Norfolk study, a British population-based cohort study. Among the 16,374 men and women who answered questions on napping habits between 1998 and 2000, a total of 3,251 died during the 13-year follow-up. Daytime napping was associated with an increased risk of all-cause mortality (for napping less than 1 hour per day on average, hazard ratio = 1.14, 95% confidence interval: 1.02, 1.27; for napping 1 hour or longer per day on average, hazard ratio = 1.32, 95% confidence interval: 1.04, 1.68), independent of age, sex, social class, educational level, marital status, employment status, body mass index, physical activity level, smoking status, alcohol intake, depression, self-reported general health, use of hypnotic drugs or other medications, time spent in bed at night, and presence of preexisting health conditions. This association was more pronounced for death from respiratory diseases (for napping less than 1 hour, hazard ratio = 1.40, 95% confidence interval: 0.95, 2.05; for napping 1 hour or more, hazard ratio = 2.56, 95% confidence interval: 1.34, 4.86) and in individuals 65 years of age or younger. Excessive daytime napping might be a useful marker of underlying health risk, particularly of respiratory problems, especially among those 65 years of age or younger. Further research is required to clarify the nature of the observed association.

Weight loss through adjustable gastric banding and improvement in daytime sleepiness: 2 year interim results of APEX study

OBJECTIVE

Obesity is one factor associated with an increased risk of obstructive sleep apnea (OSA). This study reports the investigator-reported resolution or improvement of OSA and improvements in sleep-related quality of life (QOL) 2 years after surgical placement of the LAP-BAND AP * (LBAP) system.

RESEARCH DESIGN AND METHODS

The LBAP Experience (APEX) study is an ongoing 5 year, prospective, observational study assessing change in weight, comorbidities, and QOL after LBAP implantation. This is an interim analysis of patients with evaluable data at 24 months who had OSA at baseline.

CLINICAL TRIAL REGISTRATION

NCT00501085.

RESULTS

At baseline, 117 of 395 patients (29.6%; mean body mass index [BMI], 45.0 kg/m2) reported OSA; of these, 57 had evaluable patient-reported outcome data at 2 years. Investigator-reported resolution or improvement of OSA was 69% and 86% at post-operative years 1 and 2, respectively. Patients reporting resolution, improvement, or no change in OSA experienced mean changes in BMI and percentage of weight loss of -9.7 kg/m(2)/-21.7%, -8.3 kg/m(2)/-18.7%, and -5.7 kg/m(2)/-13.2%, respectively (n = 54). Mean 2 year BMI was not statistically different between the groups (p = not significant). Mean scores for all Epworth Sleepiness Scale responses for the OSA population improved by -0.43 from baseline (p < 0.0001; n = 78) compared with -0.29 for patients without OSA at baseline (n = 177; p = 0.037 between groups). In addition, the overall study population experienced resolution and/or improvement in other obesity-related comorbidities, such as type 2 diabetes (96%) and hypertension (91%).

CONCLUSIONS

These data support that surgically facilitated weight loss can improve sleep-related QOL and may result in resolution or improvement of OSA; the degree of weight loss may be related to these changes.

Prevalence of risk factors for atrial fibrillation and stroke among 1210 patients with sleep disordered breathing

AIMS

This study sought to identify the prevalence of risk factors for atrial fibrillation and stroke in a sleep apnea population.

METHODS

Study participants included 1210 consecutive adults who were referred with suspicion of sleep apnea. Statistical analysis was used to determine the relationship between sleep apnea syndrome and risk factors for atrial fibrillation and stroke.

RESULTS

Among 1210 enrolled patients, 65.8% had severe sleep apnea (Apnea/hypopnea Index--AHI>30), 25.2% had mild to moderate sleep apnea (AHI 5 to 30), and 8.8% had no sleep apnea (AHI<5). At baseline, the mean apnea-hypopnea index in patients with sleep apnea syndrome was 35. Compared to patients with an AHI<5, those with an AHI>30 were older (47.3±11.4 vs. 52.74±12.4, p<0.001) and had a higher body mass index (BMI) (30.7±7.3 vs. 33.83±10.1, p<0.001), a higher prevalence of hypertension (38 vs. 16%, p<0.001), and a higher CHADS2 (congestive heart failure, hypertension, age, diabetes and prior stroke) score (0.59±0.8 vs. 0.28±0.64, p<0.001).

CONCLUSIONS

Patients with severe sleep apnea have a higher prevalence of risk factors for atrial fibrillation and stroke when compared with subjects without sleep apnea.

Traditional and nontraditional cardiovascular risk factors in comorbid insomnia and sleep apnea

OBJECTIVES

Insomnia and sleep apnea frequently co-occur and are independently associated with an increased risk of cardiovascular disease, but little is known about cardiovascular disease risk among individuals with comorbid insomnia and sleep apnea. The current study examined traditional risk factors and a physiologic biomarker of cardiovascular risk in comorbid insomnia and sleep apnea.

DESIGN

Community-based participatory research study.

PARTICIPANTS

The sample comprised 795 participants without preexisting cardiovascular disease from the Heart Strategies Concentrating On Risk Evaluation (Heart SCORE) study.

MEASUREMENTS AND RESULTS

Participants were assessed for symptoms of insomnia and sleep apnea risk, as well as for presence of obesity, smoking, a sedentary lifestyle, hypertension, dyslipidemia, and diabetes. Baseline resting brachial artery diameter was measured by B-mode ultrasonography. A total of 138 participants (17.4%) met criteria for insomnia syndrome alone, 179 (22.5%) were at high risk for sleep apnea alone, 95 (11.9%) reported both insomnia syndrome and high sleep apnea risk, and 383 (48.2%) reported having neither insomnia nor sleep apnea symptoms Both high sleep apnea risk alone and comorbid insomnia and high sleep apnea risk groups had greater frequencies of obesity, sedentary lifestyle, hypertension, and three or more traditional cardiovascular risk factors and significantly larger brachial artery diameters than the insomnia alone group and those without insomnia or sleep apnea symptoms. No differences in traditional cardiovascular risk factors or brachial artery diameter were found between the high sleep apnea risk and comorbid groups.

CONCLUSIONS

These findings suggest that sleep apnea is a major contributor to cardiovascular risk and co-occurring insomnia does not appear to add to this risk.

Obstructive sleep apnea syndrome is associated with higher diastolic blood pressure in men but not in women

BACKGROUND

Obstructive sleep apnea syndrome (OSAS) and poor sleep quality both increase blood pressure (BP). This study aimed to find the sex effects and the role of poor sleep quality on systolic BP (SBP) and diastolic BP (DBP) in OSAS patients.

METHODS

Polysomnographic findings, morning BP values, and clinical data of 460 subjects (348 men; 112 women) diagnosed with OSAS were analyzed. Analyses were performed separately in each sex to examine the association of the apnea-hypopnea index (AHI) with BP, SBP, DBP, and sleep quality.

RESULTS

In male subjects, AHI predicted the high BP and high DBP groups but not the high SBP group. In female subjects, AHI did not predict any of the high BP, DBP, or SBP groups. Poor sleep quality, in the absence of AHI effect, weakly correlated with BP in both sexes, but the association between poor sleep quality and high AHI was stronger in male subjects than in females.

CONCLUSIONS

In male subjects only, OSAS was associated with DBP but not SBP. The significant association between OSAS and DBP may be responsible for the BP elevations in OSAS. It could be speculated that the stronger association between poor sleep quality and OSAS in male subjects compared with females may have partly contributed to the sex effect on BP.

Adult obstructive sleep apnoea

Obstructive sleep apnoea is an increasingly common disorder of repeated upper airway collapse during sleep, leading to oxygen desaturation and disrupted sleep. Features include snoring, witnessed apnoeas, and sleepiness. Pathogenesis varies; predisposing factors include small upper airway lumen, unstable respiratory control, low arousal threshold, small lung volume, and dysfunctional upper airway dilator muscles. Risk factors include obesity, male sex, age, menopause, fluid retention, adenotonsillar hypertrophy, and smoking. Obstructive sleep apnoea causes sleepiness, road traffic accidents, and probably systemic hypertension. It has also been linked to myocardial infarction, congestive heart failure, stroke, and diabetes mellitus though not definitively. Continuous positive airway pressure is the treatment of choice, with adherence of 60-70%. Bi-level positive airway pressure or adaptive servo-ventilation can be used for patients who are intolerant to continuous positive airway pressure. Other treatments include dental devices, surgery, and weight loss.

Insights into obstructive sleep apnea research

Moderate to severe obstructive sleep apnea (OSA) occurs in 10-17% of middle aged men and 3-9% of middle-aged women with a higher prevalence among obese subjects. This condition is an independent risk factor for many cardiovascular diseases. Intermittent hypoxia is a major pathophysiologic character of OSA; it can lead to oxidative stress and inflammation, which in their turn cause endothelial dysfunction, a hallmark of atherosclerosis. Many animal models have been designed to mimic OSA in human patients to allow more in-depth investigation of biological and cellular mechanisms of this condition. This review discusses the cardiovascular outcomes of OSA and some of the animal models that are being used to investigate it.

Comparing risk of new onset diabetes mellitus in chronic kidney disease patients receiving peritoneal dialysis and hemodialysis using propensity score matching

Chronic kidney disease (CKD) patients are at risk for developing new-onset diabetes mellitus (NODM) even after hemodialysis (HD) and peritoneal dialysis (PD) treatment. It is not clear if the incidence for NODM is different in CKD patients receiving HD and PD. This study compared the risk of NODM in PD patients and HD patients.

Methods

All HD and PD patients in Taiwan Renal Registry Database from 1997 to 2005 were included and all patients were followed to December 31, 2008. The risk of NODM was analyzed in PD patients and propensity score matched HD patients using logistic regression for early type NODM (< = 6 months after dialysis) and Cox regression for late type NODM (>6 months after dialysis).

Results

A total of 2548 PD patients and 10192 HD patients who had no diabetes on the initiation of dialysis were analyzed. The incidence for NODM was 3.7 per 100 patient/year for HD and 2.4 for PD patients. HD patients are more at risk for developing early type NODM (p<0.001) with an adjusted odds ratio of 1.41 [95% confidence interval (CI) 1.12–1.78)]. HD patients are more at risk for late type NODM (p<0.001) with an adjusted hazard ratio of 2.01 (95% CI: 1.77–2.29). Patient’s age was negatively associated with risk of early type of NODM (p<0.001) but positively associated with risk of late type NODM (p<0.001).

Conclusions

Chronic kidney disease patients receiving hemodialysis are more at risk for developing new-onset diabetes mellitus compared to those receiving peritoneal dialysis.

Practice Guidelines for the Perioperative Management of Patients with Obstructive Sleep Apnea

The American Society of Anesthesiologists Committee on Standards and Practice Parameters and the Task Force on Perioperative Management of Obstructive Sleep Apnea presents an updated report of the Practice Guidelines for the Perioperative Management of Patients with Obstructive Sleep Apnea.

Supplemental Digital Content is available in the text.

High risk for obstructive sleep apnea in relation to hypertension among southeast Asian young adults: role of obesity as an effect modifier

BACKGROUND

Obstructive sleep apnea (OSA) has been linked to hypertension among middle-aged and older adults in Western countries. Few studies have focused on young adults, especially those in Southeast Asian countries undergoing epidemiologic transitions and experiencing elevated noncommunicable disease burden. We investigated associations of high risk for OSA with hypertension among Asian young adults.

METHODS

A total of 2,911 college students in Thailand participated in this study. The high risk for OSA was assessed using the Berlin Questionnaire. Blood pressure (BP) and anthropometric measurements were taken by trained research staff. Elevated BP and hypertension were defined as BP ≥ 120/80 mm Hg and ≥ 140/90 mm Hg, respectively. Multivariable logistic regression models were fit to estimate odds ratios (ORs) and 95% confidence intervals (CIs) of elevated BP and hypertension. Stratified analyses were conducted to examine whether observed associations varied by weight status.

RESULTS

High risk for OSA was significantly associated with elevated BP (OR = 2.38; 95% CI = 1.68-3.39) and hypertension (OR = 2.55; 95% CI = 1.57-4.15) after adjustment for demographic and lifestyle factors. When body mass index was further controlled for, observed associations were greatly attenuated. The associations were only evident among overweight and obese students.

CONCLUSIONS

The high risk for OSA among overweight and obese young adults is associated with elevated BP and hypertension. Enhanced efforts directed toward screening and diagnosing OSA and weight control among young adults could be one strategy for improving cardiovascular health.

Can pulse transit time be useful for detecting hypertension in patients in a sleep unit?

INTRODUCTION

Pulse transit time (PTT) is the time that a pulse wave takes to travel between two different arterial points, and may be useful in estimating blood pressure. This noninvasive technique, which does not add any cost to the procedure, offers the advantage of avoiding 'arousals' during sleep measurement as occurs with ambulatory blood pressure monitoring (ABPM). We aim to confirm the usefulness of PTT for the detection of hypertension, and to study the correlation between both measurements.

METHODS

Prospective observational study in a multidisciplinary sleep unit. We recruited 30consecutive patients attending a sleep clinic and ran a baseline polysomnography followed by an ABPM the following day. Average systolic and diastolic blood pressure (SBP, DBP) by PTT were calculated and compared with ABMP results. In accordance with international guidelines, patients with mean nocturnal ABMP ≥ 120/70 mmHg were diagnosed as having arterial hypertension.

RESULTS

Mean age of 60years; 66% male, 80% suffered from sleep apnoea (OSAS). Taking the ABPM as the reference technique, we found that the diagnostic sensitivity of PTT is 85% with a specificity of 88% in the case of SBP, with a positive predictive value of 85% and negative predictive value of 88%. By studying the relationship between mean SBP measured by ABPM and PTT, we found a linear correlation coefficient (R) of 0.88, showing a distribution of all subjects with a difference of between ±15mmHg between tests. There is also a positive correlation between mean DBP measured for the two tests, with a weaker linear correlation.

CONCLUSIONS

Pulse transit time shows a strong correlation with blood pressure (measured by ABPM). PTT provides continuous, non-invasive, cuffless blood pressure monitoring free of additional cost and could be an alternative for screening hypertension.

Influence and predicting variables of obstructive sleep apnea on cardiac function and remodeling in patients without congestive heart failure

STUDY OBJECTIVE

Obstructive sleep apnea syndrome (OSAS) has been considered to be an important predisposing factor for cardiovascular disease. This study aims to investigate the impact of OSAS on cardiac function and remodeling in patients without congestive heart failure.

METHODS

A total of 79 patients with sleep disordered breathing, preserved systolic function, and normal pro-brain natriuretic peptide level were enrolled. Sixty-five patients were classified to have moderate to severe OSAS (apnea-hypopnea index [AHI] ≥ 15/h), while the other 14 patients with mild or no OSAS (AHI < 15/h) served as control subjects. Baseline clinical and polysomnographic variables as well as tissue Doppler imaging and three-dimensional echocardiographic parameters were obtained.

RESULTS

The body mass index, neck circumference, Epworth Sleepiness Scale, desaturation index, arousal index, and snoring index were significantly higher in patients with moderate to severe OSAS than those without (p < 0.05). The left atrial size, mitral A-wave velocity, and left ventricular end-diastolic volume were significantly larger, while E/A ratio was lower in patients with moderate to severe OSAS than those without (p < 0.05). Notably, AHI in REM sleep was significantly correlated with the aortic root size, E/A ratio, left ventricular volume, and stroke volume. In addition, the area under the receiver operator characteristic curve for AHI in REM sleep ≥ 32.3/h was 0.647 (95% CI [0.525, 0.769]) in predicting the development of left ventricular diastolic dysfunction. AHI in REM sleep ≥ 32.3/h was the only independent variant in predicting diastolic dysfunction after adjusting the variables including age, gender, hypertension, and body mass index.

CONCLUSIONS

Patients with moderate to severe OSAS tend to have cardiac dysfunction revealed by echocardiography. High AHI in REM sleep is significantly associated with cardiovascular remodeling and ventricular diastolic dysfunction, and may be a potential variable to predict cardiac dysfunction.

Sleep-disordered breathing in patients with heart failure

Sleep-disordered breathing (SDB) is prevalent in patients with heart failure, and is associated with increased morbidity and mortality. SDB is proinflammatory, with nocturnal oxygen desaturations and hypercapnia appearing to play a pivotal role in the development of oxidative stress and sympathetic activation. Preliminary data suggest that attention to the diagnosis and management of SDB in patients with heart failure may improve outcomes. Ongoing research into the roles of comorbidities such as SDB as a treatment target may lead to better clinical outcomes and improved quality of life for patients with heart failure.

Excessive daytime sleepiness and adherence to antihypertensive medications among Blacks: analysis of the counseling African Americans to control hypertension (CAATCH) trial

BACKGROUND

Excessive daytime sleepiness (EDS) often occurs as a result of insufficient sleep, sleep apnea, illicit substance use, and other medical and psychiatric conditions. This study tested the hypothesis that blacks exhibiting EDS would have poorer self-reported adherence to hypertensive medication using cross-sectional data from the Counseling African-Americans to Control Hypertension (CAATCH) trial.

METHODS

A total of 1,058 hypertensive blacks (average age 57±12 years) participated in CAATCH, a randomized controlled trial evaluating the effectiveness of a multilevel intervention for participants who receive care from community health centers in New York City. Data analyzed in this study included baseline sociodemographics, medical history, EDS, and medication adherence. We used the Epworth Sleepiness Scale, with a cutoff score of ≥10, to define EDS. Medication adherence was measured using an abbreviated Morisky Medication Adherence scale, with a score >0 indicating nonadherence.

RESULTS

Of the sample, 71% were female, 72% received at least a high school education, 51% reported a history of smoking, and 33% had a history of alcohol consumption. Overall, 27% of the participants exhibited EDS, and 44% of those who exhibited EDS were classified as adherent to prescribed antihypertensive medications. Multivariable logistic regression analysis, adjusting for effects of age, body mass index, sex, education, and smoking and drinking history indicated that participants who exhibited EDS were more than twice as likely to be nonadherent (odds ratio 2.28, 95% confidence interval 1.42-3.67, P<0.001).

CONCLUSION

Analysis of the CAATCH data showed a high prevalence of EDS among hypertensive blacks. EDS is a significant predictor of nonadherence to prescribed medications for hypertension. These findings point to a modifiable variable that can be targeted in future interventions focusing on medication adherence.

Carotid artery intima-media thickness in hypertensive patients with obstructive sleep apnea

In this study we determined the relationship between the severity of obstructive sleep apnea (OSA) and body mass index (BMI), systolic and diastolic blood pressure (SBP, DBP), and carotid intima-media thickness (cIMT) in 30 hypertensive male patients, aged 30-70, with newly diagnosed OSA (15 with moderate OSA - Group A, and 15 with severe OSA - Group B) and 20 non-OSA hypertensive individuals (Group C). We revealed significant differences in cIMT between Groups B and C (0.9 ± 0.3 vs. 0.6 ± 0.1 mm and 1.0 ± 0.4 vs. 0.6 ± 0.2 mm in the right and left common carotid arteries, respectively; p <0.05). Increased carotid intima-media thickness in severe OSA was accompanied by higher systolic and diastolic blood pressures compared with both moderate OSA and control subjects. We conclude that in severe OSA increased blood pressure goes in tandem with the thickness of carotid intima-media, which helps explain increased cardiovascular risk in these patients.

Salivary markers of oxidative stress in patients with obstructive sleep apnea treated with continuous positive airway pressure

PURPOSE

Obstructive sleep apnea syndrome (OSAS) is characterized by elevated oxidative stress. Measurement of oxidative stress in saliva seems to be promising in long-term treatment monitoring of OSAS patients. In this study, our aim was to investigate whether short-term continuous positive airway pressure (CPAP) treatment would influence oxidative stress in saliva.

METHODS

Patients with diagnosed OSAS (16 women, 28 men) underwent polysomnography during the first night and CPAP treatment during the second night. Saliva samples were taken in the evening and morning on both days. Markers of oxidative stress and antioxidant status were analyzed in saliva.

RESULTS

Evening concentrations of the salivary thiobarbituric acid reacting substances (p < 0.001), advanced glycation end-products (p < 0.001), and advanced oxidation protein products (p < 0.01) were significantly lower than morning values during the diagnostic night. However, salivary concentrations of none of the oxidative stress markers were significantly influenced by the CPAP treatment. No changes in salivary antioxidant status after CPAP therapy were found.

CONCLUSION

Salivary markers of oxidative stress and antioxidant status do not change significantly after one night treatment with CPAP. On the contrary, after 1 month with CPAP therapy, reduced markers of oxidative stress were reported. Therefore, the future studies should be focused on finding the optimal sampling frequency to clarify the potential of saliva for the monitoring of OSAS treatment.

The SomnuSeal Oral Mask Is Reasonably Tolerated by Otherwise CPAP Noncompliant Patients with OSA

Compliance with CPAP is the major limiting factor in treating patients with OSA. The novel SomnuSeal mask is an oral self-adaptable mask located between the teeth and the lips ensuring that there are no air leaks or skin abrasions. Fifty patients with AHI > 20, who failed previous CPAP trials, were asked to sleep with the mask for one month. In all patients, the mask was connected to an AutoPAP machine with a heated humidifier. Efficacy, convenience, and compliance (average usage for 4 or more hours per night) were monitored. Fifty patients (41 m and 9 f, mean age 57 ± 12 years, BMI 33.6 ± 4.9 kg/m(2), and AHI 47 ± 23/h) participated. Eleven were classified as compliant (average mask usage of 26 nights, 4.7 hours per night), five were only partially compliant (average usage of 13 nights, 2.9 hours per night), and 34 could not comply with it. In all patients who slept with it, the efficacy (assessed by residual AHI derived from the CPAP device) was good with an AHI of less than 8/hour. Interestingly, the required optimal pressure decreased from an average of 9.3 cmH2O to 4.6 cmH2O. The SomnuSeal oral interface is effective and may result in converting noncompliant untreated patients with OSA into well-treated ones.

The relationship among restless legs syndrome (Willis-Ekbom Disease), hypertension, cardiovascular disease, and cerebrovascular disease

Untreated sleep disorders may contribute to secondary causes of uncontrolled hypertension, cardiovascular disease (CVD), and stroke. Restless legs syndrome, or Willis–Ekbom Disease (RLS/WED), is a common sensorimotor disorder with a circadian rhythmicity defined by an uncontrollable urge to move the legs that worsens during periods of inactivity or at rest in the evening, often resulting in sleep disruptions. Sleep disorders such as insomnia and obstructive sleep apnea (OSA) are established risk factors for increased risk of hypertension and vascular diseases. This literature review outlines the lessons learned from studies demonstrating insomnia and OSA as risk factors for hypertension and vascular diseases to support the epidemiologic and physiologic evidence suggesting a similar increase in hypertension and vascular disease risk due to RLS. Understanding the relationships between RLS and hypertension, CVD, and stroke has important implications for reducing the risks associated with these diseases.

Resistant hypertension and obstructive sleep apnea

Hypertension (HTN) is a modifiable, highly prevalent risk factor for cardiovascular morbidity and renal dysfunction worldwide. In the United States, HTN affects one in three adults, contributes to one out of every seven deaths and to nearly half of all cardiovascular disease-related deaths. HTN is considered resistant when the blood pressure remains above goal despite lifestyle modification and administration of three antihypertensive agents of different classes including a diuretic. Large population-based studies have suggested that obstructive sleep apnea (OSA) is a risk factor for resistant HTN. The mechanism proposed is a pattern of intermittent hypoxia associated with hyperaldosteronism, increased sympathetic tone, endothelial dysfunction, and inflammation. In this review we discuss the association between OSA and resistant HTN, the physiologic mechanisms linking OSA with resistant HTN, and the effect of continuous positive airway pressure therapy (CPAP) on blood pressure in patients with resistant HTN. While the reduction in blood pressure with CPAP is usually modest in patients with OSA, a decrease of only a few mmHg in blood pressure can significantly reduce cardiovascular risk. Patients presenting to a center specializing in management of hypertension should be screened and treated for OSA as a potentially modifiable risk factor.

Morbidities associated with obstructive sleep apnea

Obstructive sleep apnea (OSA)-induced biological changes include intermittent hypoxia, intermittent hypercapnia, intrathoracic pressure changes, sympathetic activation and sleep fragmentation. OSA can cause metabolic dysregulation, endothelial dysfunction, systemic inflammation, oxidative stress and hypercoagulation, and neurohumoral changes. There is evidence suggesting that OSA is independently associated with metabolic syndrome. OSA has been shown to increase the risk for systemic hypertension, pulmonary vascular disease, ischemic heart disease, cerebral vascular disease, congestive heart failure and arrhythmias. Although there are evidences accumulating that there may be a causal relationship between OSA and cardiovascular disorders, there is a need for more data from randomized controlled intervention trials to confirm this relationship. Many risk factors of OSA (age, male gender and obesity) are also known risk factors for cardiovascular disease. Severe OSA-hypopnea significantly increases the risk of fatal and nonfatal cardiovascular events in both men and women, and continuous positive airway pressure treatment reduces this risk in both. Neurocognitive consequences of OSA include daytime sleepiness, loss of alertness, memory deficit, reduced vigilance, impaired executive function, increased risk for automobile and occupational accidents, and decreased quality of life.

Intima-media thickness in patients with obstructive sleep apnea without comorbidities

Background

Obstructive sleep apnea (OSA) is associated with elevated risk of cardiovascular events. The early stages of vascular complications can be visualized by means of ultrasound. Intima-media thickness (IMT) correlates with the presence of risk factors of cardiovascular diseases such as hypertension, diabetes, tobacco smoking, or hyperlipidemia. However, little is known whether OSA itself may be the cause of IMT thickening.

Methods

The study group was composed of 28 patients (6 women, 22 men; mean age = 53.8 years, mean BMI = 27.1 kg/m², mean AHI = 22.4/h) with OSA who had no comorbidities. The control group consisted of 28 healthy subjects (6 women, 22 men; mean age = 53.9 years; mean BMI = 27.5 kg/m²). In both groups IMT was assessed in common carotid arteries with the use of ultrasonography. Additionally, in patients with OSA, pulse wave velocity, echocardiography, 24-h automated blood pressure monitoring, clinical signs and symptoms, and blood tests were performed to investigate possible correlations with IMT.

Results

Median IMT was 0.41 mm in OSA patients and 0.46 mm in the control group (p = 0.087). Echocardiography revealed left ventricle hypertrophy in 21 %, systolic disorders in 8 %, and diastolic disorders in 57 % of the patients. In a large majority of patients, pulse wave velocity was found to be normal. IMT correlated with age (r = 0.446, p = 0.017), total cholesterol (r = 0.518, p = 0.005), daytime systolic blood pressure (r = 0.422, p = 0.025), pulse pressure 24 h and daytime (r = 0.424, p = 0.027 and r = 0.449, p = 0.019), early mitral flow/atrial mitral flow (E/A) (r = −0.429, p = 0.023), and posterior wall diameter (PWD) (r = 0.417, p = 0.270).

Conclusion

In a relatively nonobese group of patients, no significant differences were found in the intima-media thickness between OSA patients without concomitant cardiovascular diseases and healthy controls. This may lead to the conclusion that IMT does not reflect increased risk of cardiovascular events in patients with isolated OSA.

Circulating adhesion molecules in obstructive sleep apnea and cardiovascular disease

Over 20 years of evidence indicates a strong association between obstructive sleep apnea (OSA) and cardiovascular disease. Although inflammatory processes have been heavily implicated as an important link between the two, the mechanism for this has not been conclusively established. Atherosclerosis may be one of the mechanisms linking OSA to cardiovascular morbidity. This review addresses the role of circulating adhesion molecules in patients with OSA, and how these may be part of the link between cardiovascular disease and OSA. There is evidence for the role of adhesion molecules in cardiovascular disease risk. Some studies, albeit with small sample sizes, also show higher levels of adhesion molecules in patients with OSA compared to controls. There are also studies that show that levels of adhesion molecules diminish with continuous positive airway pressure therapy. Limitations of these studies include small sample sizes, cross-sectional sampling, and inconsistent control for confounding variables known to influence adhesion molecule levels. There are potential novel therapies to reduce circulating adhesion molecules in patients with OSA to diminish cardiovascular disease. Understanding the role of cell adhesion molecules generated in OSA will help elucidate one mechanistic link to cardiovascular disease in patients with OSA.

Sleeping Beauty or the Beast? - Metabolic Syndrome from an Obstructive Sleep Apnoea Perspective

Obstructive sleep apnoea (OSA) is a significant health issue. Patients with cardiovascular disease as well as patients with diabetes have a high prevalence of OSA, and the prevalence of coronary heart disease, heart failure, stroke and diabetes is increased in patients with obstructive sleep apnoea. Physiological responses to OSA include sympathetic activation, neurohumoral changes and inflammation, all of which are precursors for cardiovascular disease and diabetes. International guidelines are starting to recognise the importance of OSA for patients with cardiovascular conditions such as heart failure and hypertension. Diagnosis is important, and home-based sleep testing devices can facilitate this process. Treating OSA with continuous positive airway pressure (CPAP) has been shown to reduce blood pressure (BP) in patients with hypertension, but more research is needed to determine which components of the metabolic syndrome respond best to the addition of CPAP therapy.

Neck circumference, metabolic syndrome and obstructive sleep apnea syndrome; evaluation of possible linkage

Background

This study was performed to evaluate neck circumference (NC) and metabolic syndrome (MS) parameters in severe and non-severe (mild-moderate) obstructive sleep apnea syndrome (OSAS) patients according to apnea-hypopnea index (AHI).

Material/Method

We enrolled 44 patients diagnosed with OSAS based on overnight polysomnography. The diagnosis of OSAS was based on AHI. Apnea is a pause of airflow for more than 10 seconds. and hypopnea is a decrease of airflow for more than 10 seconds and oxygen desaturation of 4% or greater. AHI score. per hour; below 5 normal. 5–29 mild-moderate. 30 and above were grouped as severe OSAS. Height. weight. neck circumference (NC). waist circumference (WC) and body mass index (BMI) of the patients were measured. MS was diagnosed by the Adult Treatment Panel (ATP) III criteria (≥3 of the following abnormalities): 1) WC ≥94 cm for males, ≥80 cm for females; 2) arterial blood pressure ≥130/85 mmHg; 3) fasting blood glucose ≥100 mg/dl; 4) high density lipoprotein (HDL) cholesterol <40 mg/dl in man, <50 mg/dl in women; 5) triglycerides ≥150 mg/dl.

Results

Mean BMI and NC were higher in severe OSAS patients compared to non-severe patients (p=0.021. p<0.001). According to ATP III criteria. 64% of severe and 61.1% of non-severe OSAS patients were MS (p=0.847). A logistic regression model displayed an association with NC as a risk factor for severe OSAS (p=0.01). but not with MS.

Conclusions

In this study. NC in severe OSAS patients was significantly higher than in non-severe OSAS patients. The prevalence of metabolic syndrome was not correlated with OSAS severity. NC is an independent risk factor for severe OSAS.

Association between perceived insufficient sleep, frequent mental distress, obesity and chronic diseases among US adults, 2009 behavioral risk factor surveillance system

Background

Although evidence suggests that poor sleep is associated with chronic disease, little research has been conducted to assess the relationships between insufficient sleep, frequent mental distress (FMD ≥14 days during the past 30 days), obesity, and chronic disease including diabetes mellitus, coronary heart disease, stroke, high blood pressure, asthma, and arthritis.

Methods

Data from 375,653 US adults aged ≥ 18 years in the 2009 Behavioral Risk Factor Surveillance System were used to assess the relationships between insufficient sleep and chronic disease. The relationships were further examined using a multivariate logistic regression model after controlling for age, sex, race/ethnicity, education, and potential mediators (FMD and obesity).

Results

The overall prevalence of insufficient sleep during the past 30 days was 10.4% for all 30 days, 17.0% for 14–29 days, 42.0% for 1–13 days, and 30.6% for zero day. The positive relationships between insufficient sleep and each of the six chronic disease were significant (p < 0.0001) after adjustment for covariates and were modestly attenuated but not fully explained by FMD. The relationships between insufficient sleep and both diabetes and high blood pressure were also modestly attenuated but not fully explained by obesity.

Conclusions

Assessment of sleep quantity and quality and additional efforts to encourage optimal sleep and sleep health should be considered in routine medical examinations. Ongoing research designed to test treatments for obesity, mental distress, or various chronic diseases should also consider assessing the impact of these treatments on sleep health.

Employer-mandated sleep apnea screening and diagnosis in commercial drivers

INTRODUCTION

Obstructive sleep apnea (OSA) is common among commercial drivers and associated with health/safety risks, leading several trucking firms to mandate OSA screening.

METHODS

A total of 19,371 commercial drivers were screened for OSA with an online questionnaire (Somni-Sage reg) through employer mandates. Questionnaire and polysomnography results were analyzed retrospectively.

RESULTS

Screening categorized 5908 drivers (30%) as higher risk. To date, employers have sent 2103 higher-risk drivers for polysomnography, demonstrating that 68% of high-risk drivers tested had an apnea-hypopnea index (AHI) greater than 10 and 80% had an AHI of 5 or more. A conservative prevalence estimate for OSA (AHI > 10) was 21% among the drivers studied.

CONCLUSIONS

Online screening followed by polysomnography for high-risk drivers demonstrates as many as 21% of commercial drivers may have OSA. Mandatory screening can have a high yield among commercial drivers.

Approaches for targeting blood pressure control in sleep disorders

PURPOSE OF REVIEW

One of the underappreciated causes of hypertension is disordered sleep. There have been a number of studies evaluating sleep in the context of blood pressure control, and these will be reviewed.

RECENT FINDINGS

Original novel articles document that disruption of deep sleep stage, regardless of cause, if chronic, contributes to an increased risk for development of hypertension. Studies have evaluated disrupted sleep especially in older people requiring use of the bathroom at night and demonstrate higher risk of hypertension in such people. Correction of sleep apnea with continuous positive airway pressure (CPAP) reduces blood pressure in those who are adherent; however, as the reduction is only from 2 to 5 mmHg systolic, adjunctive medications are almost always needed. Use of angiotensin receptor blockers and some β-blockers has shown some improvement in blood pressure. Renal denervation has also been shown in a pilot study to offer benefit on blood pressure reduction.

SUMMARY

Innovations of combined use of devices with certain classes of antihypertensive medications help reduce blood pressure in people with sleep disorders. CPAP alone provides only modest reduction in blood pressure; however, restoration of deep sleep reduces blood pressure and reduces variability.

Hypertension and obstructive sleep apnea

Obstructive sleep apnea (OSA) is increasingly being recognized as a major health burden with strong focus on the associated cardiovascular risk. Studies from the last two decades have provided strong evidence for a causal role of OSA in the development of systemic hypertension. The acute physiological changes that occur during apnea promote nocturnal hypertension and may lead to the development of sustained daytime hypertension via the pathways of sympathetic activation, inflammation, oxidative stress, and endothelial dysfunction. This review will focus on the acute hemodynamic disturbances and associated intermittent hypoxia that characterize OSA and the potential pathophysiological mechanisms responsible for the development of hypertension in OSA. In addition the epidemiology of OSA and hypertension, as well as the role of treatment of OSA, in improving blood pressure control will be examined.

Relationship between sleep disorders and the risk for developing type 2 diabetes mellitus

Sleep is increasingly being recognized as an important factor in the homeostasis of multiple body functions, including blood glucose metabolism. One of the most common sleep disorders, obstructive sleep apnea, is not only highly prevalent in patients with type 2 diabetes mellitus, but may contribute to the development of abnormalities in blood glucose metabolism. Evidence suggests that effectively treating sleep apnea, specifically with continuous positive airway pressure, improves glycemic and nonglycemic outcomes. Other common sleep disorders, such as insufficient sleep, shift work disorder, and restless legs syndrome, may also have a significant influence on the development and management of diabetes and its complications. The purpose of this article is to review the recent literature on the relationship between sleep disorders and blood glucose metabolism.

Microimplant-based mandibular advancement therapy for the treatment of snoring and obstructive sleep apnea: a prospective study

OBJECTIVE

To investigate the efficacy of orthodontic microimplant-based mandibular advancement therapies for the treatment of snoring and obstructive sleep apnea (OSA) in adult patients.

MATERIALS AND METHODS

Ten adult OSA patients (seven men, three women; mean age 60.00 ± 9.25 years) were each treated with two mandibular orthodontic microimplants attached to a customized reverse face mask for mandibular advancement. Pretreatment and posttreatment outcome measures of microimplant mobility, apnea-hypopnea index, snoring, respiratory movement, and Epworth sleepiness scores were evaluated after 6 months.

RESULTS

Highly significant reductions in the apnea-hypopnea index, snoring, and sleep variables were observed. Sixteen of the 20 (80%) microimplants were stable and showed no mobility, and four (20%) demonstrated grade 1 or 2 mobility and required removal and reinsertion of a new microimplant.

CONCLUSIONS

Favorable reductions in sleep variables highlight the potential of microimplant-based mandibular advancement therapy as an alternative treatment modality for OSA patients who cannot tolerate continuous positive airway pressure and oral appliance therapy.

Sleep complaints and daytime sleepiness among pharmaceutical students in Tripoli

Background

The effect of sleep difficulties has achieved a great deal of attention recently, with university students considered as a homogenized population, particularly affected by sleep habits.

Aim

The objective of this study was to investigate whether Libyan college students experience sleep disturbance during their academic programmes.

Methods

A cross-sectional survey was conducted in the college of Pharmacy, Tripoli University, during February 2010. A total of 201 students, including 179 females (89.05%) and 22 males (10.95%), were recruited from different academic levels. Data were collected using a structured questionnaire and included a number of life-style variables. Epworth Sleepiness Scale (ESS) was used for the assessment of daytime sleepiness.

Results

This study showed that the total sleep time (TST) on a weeknight was 6.40 h and 67 students reported napping during daytime. The TST plus naps totalled 7.39 h. Out of eight possible dozing situations, we found that the mean score for ESS was 8.78. In addition, 79 students showed an ESS score of >10. Furthermore, our results showed that the majority of students (>92%) reported poor sleep satisfaction with quality and duration of sleep hours. Thinking about difficulty of study but not increasing education programs or tea/coffee consumption is associated with sleep difficulties reported. Moreover, 77.6% of students reported an irregular sleep–wake schedule.

Conclusion

These findings indicate that students experienced excessive daytime sleepiness. The TST of pharmaceutical students in Libya, as in other developing countries, is less than those reported by Western students. Students experienced various environmental demands during their college years and, their quality of sleep was negatively affected.

Sleep apnea syndrome: experience of the pulmonology department in Ibn Sina Hospital, Rabat, Morocco

INTRODUCTION

Sleep apnea syndrome is a highly prevalent disorder that is still underdiagnosed and undertreated and whose obstructive form is the most common. The diagnosis is suspected on clinical signs collected by interrogation and questionnaires (Berlin questionnaire and Epworth sleepiness scale), then confirmed by objective sleep study findings (polygraphy or polysomnography). It is necessary to conduct studies in each context on the characteristics and management of sleep apnea syndrome comprising the testing of reliability of the questionnaires.

METHODS

Prospective and descriptive study of 104 patients addressed to sleep consultation at pulmononology Department of Ibn Sina Hospital, Morocco over a period of 5 years (January 2006 to December 2010), agreed to participate in the study, responded to a predetermined questionnaire, and benefited from clinical examination and paraclinical tests including a polygraphy or a polysomnography

RESULTS

59(56.7%) patients had an obstructive sleep apnea-hypopnea syndrome with a similar prevalence in both sexes. 32.2% of patients were obese and 28,8% had cardio-vascular diseases. Snoring, excessive daytime sleepiness and witnessed apnea were found in respectively 79.7%, 50.8% and 16.9%. Berlin questionnaire and Epworth sleepiness scale had an acceptable internal consistency against apnea hypopnea index with a Cronbach's alpha coefficient respectively 0.79 and 0.78. Depending on severity, clinical impact and results of investigations, the adequate treatment has been proposed based on the 2010 recommendations for clinical practice.

CONCLUSION

This study has provided an idea about the profile and the management of patients having an obstructive sleep apnea-hypopnea syndrome and showed that both Berlin questionnaire and Epworth sleepiness scale are two simple and reliable methods in our context. A larger and further study across the country should be considered.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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