Prevalence Of Obstructive Sleep Apnea Syndrome Research Articles

Influence of CPAP treatment on inflammation in patients with obstructive sleep apnea: Is it a matter of time or a matter of marker?

It was with a great interest that we have read the article entitled “Effect of CPAP treatment on endothelial function and plasma CRP levels in patients with sleep apnea” by Athanasios Panoutsopoulos et al. published recently in this journal [1]. After reading the article, we benefited a lot from it. In recent years our department has been studying the relationship between inflammation, coronary heart disease and sleep apnea. Athanasios Panoutsopoulos and coworkers encouraged us greatly. We would like to share our opinions about the study. The study demonstrated that Continuous positive airway pressure (CPAP) treatment had a relevant upon systemic and local inflammation and provided new insight into pathophysiological pathways of obstructive sleep apnea syndrome (OSAS). OSAS was widely accepted as a cardiovascular risk factor. The close association of OSAS and conventional cardiovascular risk factors including hypertension, diabetes mellitus, dyslipidemia and obesity added to the adverse cardiovascular complication. Studies have suggested a strong bidirectional association between OSAS and metabolic syndrome (MS). Inflammation was believed to play a role in the pathogenesis of cardiovascular disease. OSAS was closely associated with inflammation, but obesity may be a confounding factor. Obesity has emerged as one of the most prevalent diseases in the world. The mechanisms leading to obesity-related morbidities were likely multifactorial, and absolutely included activation of inflammatory pathways. Both obesity and OSAS could modulate the expression and secretion of systemic and airway inflammatory cytokines. So, we should pay certain attention to the change of weight. CPAP was effective in the treatment of OSAS, but adherence was a major barrier. The subjects completed the CPAP treatment with good adherence in this study. Several studies reported that CPAP treatment could reverse pathophysiological changes, reduce the risk of cardiovascular events and mortality in subjects with OSAS. C-reactive protein (CRP) was a prototypic marker of inflammation that has repeatedly shown promise as a potentially reliable biomarker of cardiovascular morbidity. Hypertension induced by OSAS may be multifactorial in origin, and systemic inflammation was one of the major factors. OSAS patients with hypertension have higher level of inflammation and insulin resistance. Sleep apnea was common in patients with coronary artery disease (CAD). Inflammatory processes played an important role in the pathogenesis of atherosclerosis. Inflammation may be linked to CAD progression by accelerating atherosclerotic processes. Statins has been widely utilized to reduce cardiovascular risk in patients with cardiovascular disease. The benefit has been attributed both to cholesterol lowering and “anti-inflammatory” effects. Smoking was a known risk factor and was reported to be associated with an increased prevalence of OSAS. Due to the smoking-induced upper airway inflammation and stimulant effects of nicotine on upper airway, smoking may participate in the pathophysiology of OSA. Some studies confirmed that physical exercise could improve excessive daytime sleepiness due to its improvement in inflammatory profiles.

Gender-related Differences in the Obstructive Sleep Apnea Syndrome

The obstructive sleep apnea syndrome (OSAS) is associated with increased morbidity and mortality. Epidemiological studies suggest a two-fold higher prevalence of OSAS in men than in women. Differences in pharyngeal collapsibility and central respiratory drive may play a significant role in the gender-specific pathogenesis. Compared with their male counterparts, female patients experience OSAS at an older age (postmenopausal) and with higher body-mass-index. Female OSAS patients furthermore more frequently report atypical symptoms, such as insomnia, depression, and/or restless legs, and thus are less likely to be referred for the evaluation of sleep disordered breathing. Knowledge about these distinct gender-related differences in clinical features of OSAS may contribute to an increased awareness, improved diagnosis and its therapeutic consequences.

Diagnosis and Management of Childhood Obstructive Sleep Apnea Syndrome

This technical report describes the procedures involved in developing recommendations on the management of childhood obstructive sleep apnea syndrome (OSAS). The literature from 1999 through 2011 was evaluated. A total of 3166 titles were reviewed, of which 350 provided relevant data. Most articles were level II through IV. The prevalence of OSAS ranged from 0% to 5.7%, with obesity being an independent risk factor. OSAS was associated with cardiovascular, growth, and neurobehavioral abnormalities and possibly inflammation. Most diagnostic screening tests had low sensitivity and specificity. Treatment of OSAS resulted in improvements in behavior and attention and likely improvement in cognitive abilities. Primary treatment is adenotonsillectomy (AT). Data were insufficient to recommend specific surgical techniques; however, children undergoing partial tonsillectomy should be monitored for possible recurrence of OSAS. Although OSAS improved postoperatively, the proportion of patients who had residual OSAS ranged from 13% to 29% in low-risk populations to 73% when obese children were included and stricter polysomnographic criteria were used. Nevertheless, OSAS may improve after AT even in obese children, thus supporting surgery as a reasonable initial treatment. A significant number of obese patients required intubation or continuous positive airway pressure (CPAP) postoperatively, which reinforces the need for inpatient observation. CPAP was effective in the treatment of OSAS, but adherence is a major barrier. For this reason, CPAP is not recommended as first-line therapy for OSAS when AT is an option. Intranasal steroids may ameliorate mild OSAS, but follow-up is needed. Data were insufficient to recommend rapid maxillary expansion.

Sleep apnea and pregnancy. An association worthy of study

Pregnancy involves major physiological and hormonal changes that have important implications in many areas of health, including sleep. Reports exist during pregnancy, predominantly in the first and last trimesters, describing changes in the quality and quantity of sleep [1]. Increased prevalence of snoring and excessive daytime sleepiness has also been described [2]. Sleepiness is a prevalent symptom in the general population, although it is difficult to assess objectively. Its presence is characteristic of obstructive sleep apnea syndrome (OSAS) but not exclusive to it. In fact, OSAS patients have a diverse phenotypic expression and do not always present this symptom. Excessive daytime sleepiness presents low sensitivity and specificity for the diagnosis of OSAS. In the study published in this issue of Sleep and Breathing, Bourjeily et al. [3] point out that daytime sleepiness may not always be considered physiologically normal during pregnancy and may be due to other factors, including sleep-disordered breathing. The presence of other associated symptoms, such as snoring or apneic breathing, should raise suspicion. The prevalence and severity of OSAS in pregnant women have not been clearly established. This is partly because the disease has historically received little attention in the field of obstetrics and because polysomnographic studies are difficult to accept during pregnancy. The majority of studies

Prevalence of and risk factors for obstructive sleep apnea syndrome in Brazilian railroad workers

This study evaluated the prevalence of, and the risk factors for, obstructive sleep apnea syndrome (OSAS) among Brazilian railroad workers. Male railroad workers (745) from a railway company in Brazil were analyzed after responding to questionnaires about their demographics, sleep habits, excessive daytime sleepiness (Epworth), and the likelihood of having apnea (Berlin). We also performed polysomnography and measured anthropometric data for all of the railroad workers. The results showed that 261 (35.03%) of the railroad workers presented with OSAS. These railroad workers were older (OSAS: 38.53±10.08 versus non-OSAS: 33.99±8.92 years), more obese according to body mass index (27.70±4.38 versus 26.22±3.92 kg/m(2)), and employed for a longer period of time (14.32±9.13 years) compared with those without OSAS (10.96±7.66 years). Among those with OSAS, 9.5% were smokers and 54.7% reported alcohol use. The associated risk factors were age (OR=2.51, 95% CI=1.76-3.57), BMI (OR=1.56, 95% CI=1.04-2.34), alcohol use (OR=1.28, 95% CI=0.90-1.81), and a high chance of having sleep apnea, as assessed by the Berlin questionnaire (OR=2.19, 95% CI=1.49-3.21). The prevalence of OSAS in Brazilian railroad workers was higher than that observed in the general population but similar to that found in the population of the city of São Paulo, Brazil. These results suggest that age, BMI, a high risk of developing apnea through subjective self-reporting (Berlin), and alcohol use are associated with a higher risk of developing OSAS. These data reinforce the need to be more attentive to this population because they have a higher propensity for accidents.

Obstructive sleep apnoea in Treacher Collins syndrome: prevalence, severity and cause

This cohort study in 35 patients (13 children) evaluates the prevalence, severity and anatomical cause of obstructive sleep apnoea syndrome (OSAS) in patients with Treacher Collins syndrome. Ambulatory polysomnography was performed cross-sectionally to determine OSAS prevalence and severity. All upper airway related surgical interventions were evaluated retrospectively. In 11 patients, sleep endoscopy, and flexible and rigid endoscopy were applied to determine the level of anatomical obstruction of the upper airway. The overall prevalence of OSAS in Treacher Collins patients was 46% (54% in children; 41% in adults). Thirty-eight upper airway related surgical interventions were performed in 17 patients. Examination of the upper airway revealed various anatomical levels of obstruction, from the nasal septum to the trachea. Most significant obstruction was found at the level of the oro/hypopharynx. OSAS in Treacher Collins patients is an important problem so all patients should be screened for OSAS by polysomnography. Endoscopy of the upper airways was helpful in determining the level of obstruction. Surgical treatment at one level will not resolve OSAS in most patients because OSAS in Treacher Collins has a multilevel origin. Non-invasive ventilation (continuous positive airway pressure or bilevel positive airway pressure) or tracheotomy should be considered as a treatment modality.

Rapid eye movement related obstructive sleep apnea syndrome: antropometric and polysomnographic findings

Obstructive sleep apnea syndrome is characterized by episodic narrowing of the upper respiratory ways accompanied by an oxygen desaturation during sleep. REM-related obstructive sleep apnea syndrome, comprises a subgroup of sleep disordered breathing with a 10-36% frequency. The aim of the present study is to analyze the frequency, the antropometric and polygraphic features of REM-related obstructive sleep apnea syndrome. A total of 427 cases [332 males (77.4%) and 95 females (22.6%)] with definitive obstructive sleep apnea syndrome diagnosis with polysomnography records were included into the study. Of all the cases, 108 (25.3%) were REM-related sleep respiratory disorder. There was no difference between the two groups with regard to age and sex. However, the obstructive sleep apnea syndrome group non-related to REM demonstrated a more severe obstructive sleep apnea syndrome and a longer neck circumference. Superficial sleep was longer in the REM non-related group, while deep refreshing sleep (Non-REM 3) was longer in the REM-related group. The subgroup analysis of the REM-related group with regard to sex revealed a higher body mass index in the female subgroup. REM-related sleep respiratory disorder is more often in mild-to-moderate obstructive sleep apnea syndrome cases, the male/female ratio of REM-related sleep respiratory disorder is not different from the obstructive sleep apnea syndrome prevalence in the community.

Erectile dysfunction in obstructive sleep apnea syndrome—Prevalence and determinants

IntroductionOSAS (obstructive sleep apnea syndrome) is defined by recurrent episodes of upper airway obstruction during sleep, causing multiple clinical consequences. Literature review suggests that OSAS induces a spectrum of abnormalities in neural, hormonal and vascular regulation that contribute to the development of ED (erectile dysfunction).The aims of this study were to estimate the prevalence of ED in OSAS patients and evaluate its determinants. Methods62 patients from Hospital S. João Sleep Laboratory with newly diagnosed OSAS were included in the study and answered the IIEF-5 (international index erectile function 5 item version) questionnaire. ResultsThe prevalence of ED in OSAS patients was 64.4%. Age and diabetes constituted themselves as independent risk factors for more severe degrees of ED: OR=1.226 (95% CI: 1.062–1.415) and OR=31.205 (95% CI: 1.222–796.557), respectively. Compared with nonsmokers, ex-smokers group revealed a positive association with ED: OR=4.32 (95% CI: 1.09–17.11). Hypertension and ACEI (angiotensin converting enzyme inhibitors) or ARB (angiotensin II receptor blockers) therapy were also correlated to ED symptoms: OR=3.25 (95% CI: 1.09–9.65) and 7.39 (95% CI: 1.52–35.99), respectively.No association was found relating BMI (p=0.254), alcoholic habits (p=0.357), acute myocardial infarction (p=0.315), dyslipidemia (p=0.239), metabolic syndrome (p=0.215) and ED.OSAS severity was not associated with ED in our sample. ConclusionsThe prevalence of ED in OSAS patients is high. ED determinants in our sample were age and diabetes. Past smoking habits, hypertension and ACEI/ARB therapy also revealed a statistically significant association with ED.

Tempol Ameliorates Pharyngeal Dilator Muscle Dysfunction in a Rodent Model of Chronic Intermittent Hypoxia

Respiratory muscle dysfunction is implicated in the pathophysiology of obstructive sleep apnea syndrome (OSAS), an oxidative stress disorder prevalent in men. Pharmacotherapy for OSAS is an attractive option, and antioxidant treatments may prove beneficial. We examined the effects of chronic intermittent hypoxia (CIH) on breathing and pharyngeal dilator muscle structure and function in male and female rats. Additionally, we tested the efficacy of antioxidant treatment in preventing (chronic administration) or reversing (acute administration) CIH-induced effects in male rats. Adult male and female Wistar rats were exposed to alternating cycles of normoxia and hypoxia (90 s each; Fi(O(2)) = 5% O(2) at nadir; Sa(O(2)) ∼ 80%) or sham treatment for 8 h/d for 9 days. Tempol (1 mM, superoxide dismutase mimetic) was administered to subgroups of sham- and CIH-treated animals. Breathing was assessed by whole-body plethysmography. Sternohyoid muscle contractile and endurance properties were examined in vitro. Muscle fiber type and cross-sectional area and the activity of key metabolic enzymes were determined. CIH decreased sternohyoid muscle force in male rats only. This was not attributable to fiber transitions or alterations in oxidative or glycolytic enzyme activity. Muscle weakness after CIH was prevented by chronic Tempol supplementation and was reversed by acute antioxidant treatment in vitro. CIH increased normoxic ventilation in male rats only. Sex differences exist in the effects of CIH on the respiratory system, which may contribute to the higher prevalence of OSAS in male subjects. Antioxidant treatment may be beneficial as an adjunct OSAS therapy.

No Evidence for Diagnostic Value of Mallampati Score in Patients Suspected of Having Obstructive Sleep Apnea Syndrome

To analyze whether the Mallampati score is reliable as a simple diagnostic test for predicting obstructive sleep apnea syndrome (OSAS). A literature search was performed using PubMed, Embase, Scopus, Cochrane, and CINAHL databases. Studies were ranked by their relevance and validity in a critical appraisal table. Positive and negative predictive values were obtained or recalculated from the selected articles. Eight relevant articles met the inclusion criteria. Three studies reported predictive values for a Mallampati score of 3 to 4. The prevalence (or prior probability) of OSAS in these 3 studies was 58% (95% confidence interval [CI], 50-67), 76% (95% CI, 72-79), and 82% (95% CI, 80-84), respectively. With a Mallampati score of 1 to 2, the risk of OSAS decreases to 45% (95% CI, 33-58), 74% (95% CI, 70-78), and 81% (95% CI, 77-86), respectively. With a Mallampati score of 3 to 4, the risk of OSAS is 69% (95% CI, 59-80), 82% (95% CI, 74-89), and 82% (95% CI, 79-85), respectively. The differences between the prior and the posterior probabilities are rather small and do not reach statistical significance. There is no evidence to maintain that the Mallampati score is of added value for ruling in or ruling out a diagnosis of OSAS in patients suspected for OSAS.

Inflammatory pathways in children with insufficient or disordered sleep

Sleep is not only an essential physiological function, but also serves important roles in promoting growth, maturation, and overall health of children and adolescents. There is increasing interest regarding the impact of sleep and its disorders on the regulation of inflammatory processes and end-organ morbidities, particularly in the context of metabolic and cardiovascular diseases (CVD) and their complications. Obstructive sleep apnea syndrome (OSAS) is an increasingly common health problem in children, and in the last decade, the emergence of increasing obesity rates has further led to remarkable increases in the prevalence of OSAS, along with more prominent neurocognitive, behavioral, cardiovascular and metabolic morbidities. Although the underlying mechanisms leading to OSAS-induced morbidities are likely multi-factorial, and remain to be fully elucidated, activation of inflammatory pathways by OSAS has emerged as an important pathophysiological component of the end-organ injury associated with this disorder. To this effect, it would appear that OSAS could be viewed as a chronic, low-grade inflammatory disorder. Furthermore, the concurrent presence of obesity and OSAS poses a theoretically increased risk of OSAS-related complications. In this review, we will critically review the current state of research regarding the impact of insufficient and disrupted sleep and OSAS on the immune processes and inflammatory pathways that underlie childhood OSAS as a distinctive systemic inflammatory condition in children, and will explore potential interactions between OSAS and obesity.

Effects of Race on Upper Airway Dynamic Function During Sleep in Children

Studies in adults and children have shown that African American race is a risk factor for the obstructive sleep apnea syndrome (OSAS). Therefore, we hypothesized that non-obese, non-snoring African American children would have a more collapsible upper airway during sleep than age-, gender-, and size-matched Caucasians. Upper airway dynamic function was measured during sleep in normal African American and Caucasian children. Sleep laboratory. 56 normal children between the ages of 8-18 years. Pressure-flow relationships were measured during NREM sleep. Nasal pressure was decreased to subatmospheric levels, using previously described techniques that resulted in an activated and relatively hypotonic upper airway. The activated and hypotonic critical pressures (Pcrit) were -25 (-25, -3) (median, range) and -19 (-25, -3) for African Americans, and -25 (-25, -4) and -25 (-25.0, -4) cm H(2)O, respectively, for Caucasians. The slopes of the pressure-flow response (SPF) under activated and hypotonic conditions for African Americans were 10 (-9, 46) and 13 (-20, 46), and for Caucasians 9 (-9, 64) and 8 (-5, 54) mL/s/cm H(2)O, respectively. There were no significant differences between groups for Pcrit or SPF under either activated or hypotonic conditions. Upper airway collapsibility was similar in asymptomatic, non-obese African American and Caucasian children. Differences in upper airway characteristics and neuromotor function cannot explain the increased prevalence of OSAS in African American children.

Portable monitoring in sleep apnoea: the way forward?

Population-based epidemiological studies estimate the prevalence of obstructive sleep apnoea syndrome (OSAS) to be at least 2% of adult females and 4% of adult males in the developed world based on an apnoea/hypopnoea frequency (AHI) of >5 events·h−1 associated with excessive daytime sleepiness. However, a substantial proportion of these individuals are undiagnosed 1–3. Furthermore, it is very likely that these epidemiological data, now dating back many years, underestimate the current prevalence of OSAS given the dramatic increase in obesity over recent decades 4. Existing evidence points to OSAS as an independent risk factor for motor vehicle accidents, neurocognitive deficits, and cardiovascular morbidity and mortality 5–8. Substantial evidence also supports the argument that appropriate treatment of OSAS reduces the risk of these consequences 9–11. Since the diagnosis of OSAS requires both clinical assessment and objective monitoring of sleep-disordered breathing 12, there are major resource implications for the management of patients with suspected sleep apnoea. However, the perceived need in many healthcare systems to perform costly and labour-intensive polysomnography (PSG) in a sleep laboratory limits patient access to diagnosis and treatment 13. Commercially available and relatively inexpensive portable monitors might facilitate earlier recognition of disease and faster initiation of treatment, thereby reducing the healthcare burden associated with OSAS 14. Interest in the clinical application of portable monitoring devices is growing rapidly, and is being used as a mainstay approach to the management of OSAS in some settings. This interest is also supported by the lack of obvious clinical benefit when using full PSG rather than simplified monitoring, as evidenced in a US health technology assessment 15. An international workshop to determine the research priorities in ambulatory management of adults with OSAS was held on October 15–16, 2007, …

Epidemiology of obstructive sleep apnoea syndrome in Chinese children: a two-phase community study

ObjectiveTo determine the prevalence and risk factors of obstructive sleep apnoea syndrome (OSAS) in Chinese children using a two-phase community-based study design.MethodsChildren from 13 primary schools were randomly recruited. A...

Sleep Apnea: Why Should We Look for Cardiac Biomarkers?

Sleep Apnea: Why Should We Look for Cardiac Biomarkers?

Prevalence of sleep apnea in HRH Princess Maha Chakri Srinthorn Medical Center, Thailand

Many studies have been conducted to find the prevalence of obstructive sleep apnea (OSA) in Western countries. Limited data have been demonstrated in Asian countries; however, no such data have been reported in Thailand. The purpose of this study was to examine the prevalence of OSA and their related factors in Thai adults. This study was performed in a university hospital in a rural area of central Thailand and data were collected. The population included office-based workers and people who came to contact with the hospital. Among the total of 2,685 participants at the baseline examination, a random sample of 199 men and women was studied with employment of overnight full polysomnography to determine the prevalence of OSA and OSA syndrome (OSAS). The percentage of habitual snorers in the study population was 26.4%. The prevalence of OSA (apnea-hypopnea index 5) was 11.4%. When OSAS was defined by an apnea-hypopnea index 5 plus excessive daytime sleepiness, its prevalence was 4.4%. The prevalence of OSA and OSAS in men was 15.4% and 4.8% and in women was 6.3% and 1.9%, respectively. Logistic regression analyses showed that gender, body mass index, age, hypertension, alcohol consumption, and smoking were associated with the risk of OSA. This study demonstrates that OSA is a common problem in the Thai adult population as in Western and other Asian countries. Understanding and treatment may be essential to reduce the risk of related medical problems.

Primary open angle glaucoma and snoring: Prevalence of OSAS

Obstructive sleep apnea syndrome (OSAS) may be suspected at interview, notably in case of snoring. Various studies suggested a link between primary open angle glaucoma (POAG) and OSAS. The present study sought to determine OSAS prevalence in POAG associated with snoring. Thirty-one snoring glaucomatous patients prospectively underwent simplified polysomnography. Ophthalmologic examination ruled out secondary glaucoma and assessed the glaucomatous neuropathy. 49% of the patients included were diagnosed with OSAS. Ophthalmologically, glaucoma showed no specific characteristics. Given the high-prevalence of OSAS in patients with POAG, presence of snoring should be explored at interview. Conversely, patients who snore should be asked whether they have POAG, and if so, should undergo all-night sleep recording to explore for OSAS.

Obstructive sleep apnea and cognitive impairment in the elderly

Obstructive Sleep Apnea Syndrome (OSAS) is characterized by repeated episodes of upper airway obstruction during sleep that result in intermittent hypoxemia and arousal. The prevalence of OSAS increases with aging, occurring in up to 25% of older adults and up to 48% in patients with Alzheimer's disease. OSAS causes hypoxia, fragmented sleep, daytime sleepiness, cognitive dysfunction, functional decline, and brain damage resulting from reduced cerebral blood flow, ischemic brain lesions, microvascular reactivity, white matter lesions, and grey matter loss. OSAS is considered as an independent risk factor for hypertension, stroke and mortality. The treatment of choice for OSAS is continuous positive airway pressure (CPAP). OSAS-related cognitive dysfunction has been shown in a variety of domains including attention, executive functioning, motor efficiency, working memory, and long-term episodic memory. Proposed mechanisms include hypoxemia, sleep fragmentation and inflammatory process, but it remains unclear which mechanisms underlie the relationship between OSAS and disturbances in the different cognitive domains. Recent studies suggest that OSAS may exacerbate cognitive functioning in dementia and that CPAP therapy can be applied to these patients and improve cognitive functioning.

Excessive Daytime Sleepiness Among Japanese Public Transportation Drivers Engaged in Shiftwork

To explore the actual condition of sleep disorders underlying subjective excessive daytime sleepiness (EDS) among train and bus drivers engaged in shiftwork. This study targeted 3109 public transportation drivers. Clinical diagnoses were made based on 147 drivers who claimed to have subjective EDS, and 285 drivers who were judged to have obstructive sleep apnea syndrome (OSAS), based on the screening process. Among these subjects, the prevalence of OSAS was 3.7% and that of shiftwork disorder (SWD) was 1.5%. SWD was common among drivers who had EDS (32.7% of drivers with EDS), and their EDS severity was higher than that of OSAS drivers. The drivers with SWD were mostly young and neither obese nor hypertensive. Encouraging awareness of SWD and OSAS could be necessary to prevent sleepiness-related accidents.

HYPERTENSIVE IMMIGRANTS ARE CHARACTERIZED BY LOWER PREVELANCE OF OBSTRUCTIVE SLEEP APNEA COMPARED TO NATIVE HYPERTENSIVES: A DIFFERENCE BEYOND ARTERIAL STIFFNESS: PP.32.281

Objective: Obstructive sleep apnea syndrome (OSAS) and essential hypertension (EH) are closely associated, while increased arterial stiffness is a marker of diffuse vascular disease. In light of the mass immigration of Eastern European residents, we sought to investigate the prevalence of OSAS along with the assessment of the arterial stiffness within this high risk population Design and Method: We studied 67 Eastern European immigrants with newly diagnosed untreated stage I-II EH (aged = 51.5 ± 15 years, 35 = male, office blood pressure (BP) = 158/92 mm Hg), who immigrated to Greece within the previous two years and 61 untreated hypertensive native inhabitants, matched for age, gender, office BP and smoking status. All participants underwent polysomnography (apnea/hypopnea index >5) and arterial stiffness evaluation on the basis of carotid to femoral pulse wave velocity (c-f PWV) by means of a computerized method (Complior SP), while metabolic profile and anthropometric data were assessed as well. Results: Hypertensive immigrants compared to native ones demonstrated decreased prevalence of OSAS (9.1% vs 12%,p = 0.014) and decreased levels of body mass index (29.3 ± 4 vs 32.2 ± 4 kg/m2,p < 0.05). There was evidence that c-f PWV was elevated in the group of immigrants (8.4 ± 0.3 vs 7.2 ± 0.5 m/sec,p < 0.05). Immigrants also exhibited decreased waist circumference (94 ± 3 vs101 ± 2 cm,p < 0.05). The two groups did not differ with regard to serum glucose and cholesterol levels (99 ± 9 vs102 ± 8 mg/dl and 226 ± 40 vs 228 ± 35 mg/dl, respectively,p = NS in both cases). Analysis of covariance revealed that the prevalence of OSAS and c-f PWV values remained statistically different between the two groups after adjustment for confounding factors (p < 0.05). Conclusions: Hypertensive immigrants demonstrate lower prevalence of OSAS but they seem to have stiffer aorta compared to native hypertensives. Efforts should be directed at this vulnerable population focusing on putative mechanisms for this unfavourable and apparently paradox BP phenotype.