Is there a correlation between OSAS duration/severity and carotid intima-media thickness?

Insights into the Use of Point-of-Care Ultrasound for Diagnosing Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is a sleeping disorder caused by complete or partial disturbance of breathing during the night. Existing screening methods include questionnaire-based evaluations which are time-consuming, vary in specificity, and are not globally adopted. Point-of-care ultrasound (PoCUS), on the other hand, is a painless, inexpensive, portable, and useful tool that has already been introduced for the evaluation of upper airways by anesthetists. PoCUS could also serve as a potential screening tool for the diagnosis of OSA by measuring different airway parameters, including retropalatal pharynx transverse diameter, tongue base thickness, distance between lingual arteries, lateral parapharyngeal wall thickness, palatine tonsil volume, and some non-airway parameters like carotid intima-media thickness, mesenteric fat thickness, and diaphragm characteristics. This study reviewed previously reported studies to highlight the importance of PoCUS as a potential screening tool for OSA.

Upregulation of HMGB1 promotes vascular dysfunction in the soft palate of patients with obstructive sleep apnea via the TLR4/NF-κB/VEGF pathway

Obstructive sleep apnea (OSA) is characterized by the collapse of the soft palate in the upper airway, resulting in chronic intermittent hypoxia during sleep. Therefore, an understanding of the molecular mechanisms underlying pathophysiological dysfunction of the soft palate in OSA is necessary for the development of new therapeutic strategies. In the present study, we observed that high mobility group protein box 1 (HMGB1) was released by a large infiltration of macrophages in the soft palate of OSA patients. The toll-like receptor 4/nuclear factor kappa B pathway was observed to be activated by the release of HMGB1, and this was accompanied by an increased expression of pro-inflammatory factors, including tumor necrosis factor-α and interleukin-6. Importantly, increased expression of toll-like receptor 4 was observed in endothelial cells, contributing to upregulation of the angiogenesis-related factors vascular endothelial-derived growth factor and matrix metalloproteinase 9. Moreover, we confirmed the effect of the HMGB1-mediated toll-like receptor 4/nuclear factor kappa B pathway on cell proliferation and angiogenesis in an in vitro cell model of human umbilical vein endothelial cells. We conclude that HMGB1 may be a potential therapeutic target for preventing angiogenesis and pathology in OSA.

Obstructive sleep apnea, myocardial perfusion and myocardial blood flow: A study of older male twins

BACKGROUND

Obstructive sleep apnea (OSA) has been associated with incidence of cardiovascular disease and with nocturnal angina, but evidence of a link with coronary atherosclerosis and myocardial ischemia is limited and previous studies may have been affected by selection bias or unmeasured confounding factors.

METHODS

We performed overnight polysomnography in 178 older male twins. The Apnea/Hypopnea Index (AHI) was calculated to assess OSA from the overnight sleep evaluation. AHI ≥15 was used as indicator of moderate/severe OSA. The following day, twins underwent myocardial perfusion imaging with [82Rb]-chloride positron emission tomography. Quantitative and semiquantitative measures of myocardial perfusion and absolute myocardial blood flow were obtained.

RESULTS

The mean age was 68 years and 40% of the sample had an AHI≥15, which indicates moderate to severe OSA. Abnormal myocardial perfusion, both with stress and at rest, was more common in twins with elevated AHI. After adjusting for clinical, lifestyle and behavioral factors, and previous history of cardiovascular disease, twins with AHI ≥15 had 3.6 higher odds (95% CI, 1.5-8.9) of an abnormal total severity score, defined as a score ≥100, and for each 5-point increment in AHI, the odds of abnormality increased by 20% (95% CI, 7%-34%). Twin pairs where both twins had OSA exhibited the greatest risk. There were no differences in measures of ischemia and absolute myocardial blood flow and flow reserve by AHI status.

CONCLUSIONS

OSA is associated with myocardial perfusion abnormalities that suggest prior subclinical myocardial scarring or infarction. Early environmental factors that affect both twins equally may play a role and should be further explored.

Stratifying the Risk of Cardiovascular Disease in Obstructive Sleep Apnea Using Machine Learning

OBJECTIVES/HYPOTHESIS

Obstructive sleep apnea (OSA) is associated with higher risk of morbidity and mortality related to cardiovascular disease (CVD). Due to overlapping clinical risk factors, identifying high-risk patients with OSA who are likely to develop CVD remains challenging. We aimed to identify baseline clinical factors associated with the future development of CVD in patients with OSA.

STUDY DESIGN

Retrospective analysis of prospectively collected data.

METHODS

We performed a retrospective analysis of 967 adults aged 45 to 84 years and enrolled in the Multi-Ethnic Study of Atherosclerosis. Six machine learning models were created using baseline clinical factors initially identified by stepwise variable selection. The performance of these models for the prediction of additional risk of CVD in OSA was calculated. Additionally, these models were evaluated for interpretability using locally interpretable model-agnostic explanations.

RESULTS

Of the 967 adults without baseline OSA or CVD, 116 were diagnosed with OSA and CVD and 851 with OSA alone 10 years after enrollment. The best performing models included random forest (sensitivity 84%, specificity 99%, balanced accuracy 91%) and bootstrap aggregation (sensitivity 84%, specificity 100%, balanced accuracy 92%). The strongest predictors of OSA and CVD versus OSA alone were fasting glucose >91 mg/dL, diastolic pressure >73 mm Hg, and age >59 years.

CONCLUSION

In the selected study population of adults without OSA or CVD at baseline, the strongest predictors of CVD in patients with OSA include fasting glucose, diastolic pressure, and age. These results may shape a strategy for cardiovascular risk stratification in patients with OSA and early intervention to mitigate CVD-related morbidity.

LEVEL OF EVIDENCE

3 Laryngoscope, 132:234-241, 2022.

Association of sleep apnea with outcomes in peripheral artery disease: Insights from the PORTRAIT study

BACKGROUND

Sleep apnea is a predictor of adverse cardiovascular outcome in many cardiovascular diseases but whether it is associated with worse health status outcomes or mortality in peripheral artery disease (PAD) is unknown.

METHODS

PORTRAIT is an international (US, Netherlands, Australia) prospective PAD registry that consecutively enrolled patients who presented with new-onset or recent exacerbations of PAD symptoms to any of 16 vascular specialty clinics. Health status was assessed upon presentation and at 12 months with the disease-specific Peripheral Artery Questionnaire (PAQ). Higher PAQ scores indicate better health status. A sequentially-adjusted hierarchical linear regression model examined the association between sleep apnea and 1-year PAQ symptoms, quality of life, and summary scores. Five-year survival curves by comorbid sleep apnea status for US patients were compared using the log-rank test.

RESULTS

The mean age of the 1204 PORTRAIT participants was 67.6 ± 9.4 years with 37.5% women and 8.3% (n = 100) having sleep apnea. Patients with sleep apnea were more likely to be from the US, more sedentary, and to have diabetes, obesity, coronary disease, more depressive symptoms and a history of prior peripheral interventions. Paradoxically, they also had higher ankle-brachial indices, but lower PAQ Summary scores at presentation and 12 months (41.2 ± 22.0 vs. 49. 9± 21.6 and 58.6 ± 27.9 vs. 71.3 ± 24.9, respectively, p = <0.05). The association between sleep apnea and 1-year health status persisted after multivariable adjustment, but there were no differences in all-cause mortality over 5 years (28.0% vs. 23.4%, p = 0.76).

CONCLUSION

In patients presenting with PAD, comorbid sleep apnea is independently associated with worse health status over time. Future studies should test whether better treatment of sleep apnea can improve the health status of patients with PAD.

CLINICAL TRIAL REGISTRATION

NCT01419080.

Markers of cardiovascular disease risk in sleep-disordered breathing with or without comorbidities: the Nagahama Study

STUDY OBJECTIVES

Whether the association between sleep-disordered breathing (SDB) and cardiovascular disease (CVD) is independent of comorbid risk factors for CVD is controversial. The objective of this study is to elucidate whether the association between SDB severity and the surrogate markers of CVD evets differs in relation to the number of comorbidities.

METHODS

This cross-sectional study included 7731 participants. Severity of SDB was determined by the oxygen desaturation index adjusted by actigraph-measured objective sleep time. Participants were stratified according to SDB severity and the number of comorbidities (hypertension, diabetes, dyslipidemia and obesity), and the associations between the maximum value of intima-media thickness of the common carotid artery (CCA-IMT-max), brachial-ankle pulse wave velocity (baPWV) and cardio-ankle vascular index (CAVI) were evaluated.

RESULTS

Among participants with no risk factor, CCA-IMT-max increased according to SDB severity (n = 1022, P <0.0001). Even after the matching of background, the median CCA-IMT-max value was 14% higher in moderate-severe SDB cases than those without SDB (n=45 in each group, P=0.020). The difference was not significant for baPWV and CAVI. On the other hand, a significant difference in CCA-IMT-max was not found in those with multiple comorbidities. Consistently, multiple regression analysis revealed an independent association between CCA-IMT-max and moderate-severe SDB for all study participants (β: 0.0222 (95% confidence interval: 0.0039-0.0405), P=0.017), but the association was not significant for stratified participants with multiple comorbidities.

CONCLUSIONS

SDB severity is associated with the CCA-IMT-max level, but the independent association becomes weaker for those with multiple comorbidities.

Gender differences of clinical and polysomnographic findings with obstructive sleep apnea syndrome

Obstructive sleep apnea syndrome (OSAS) is underdiagnosed in females and gender differences in clinical and polysomnographic findings have not been widely investigated in China. We examined clinical and polysomnographic differences between males and females with OSAS in order to determine the influence of gender on clinical presentation and polysomnographic features. Data were collected from 303 adult patients diagnosed with OSAS (237 males and 66 females) from 2017 to 2019. All the patients completed physical examination, Epworth sleepiness scale, and whole night polysomnography. AVONA, univariate and multivariate logistic regression analyses were conducted to assess gender differences of clinical and polysomnographic findings with OSAS. P < 0.05 was statistically significant. The average age was 48.4 ± 12.6 years for females and 43.4 ± 12.4 years for males. Compared with female patients with OSAS, male patients were taller and heavier, had higher systolic blood pressure in the morning, shorter duration of slow wave sleep, more micro-arousal events, greater AHI, and more complex sleep apnea events. There are obvious gender differences of clinical and polysomnographic characteristics with OSAS. Understanding gender differences will contribute to better clinical recognition of OSAS in females as well as the provision of proper health care and therapeutic practice.

Point-of-Care Ultrasound for Obstructive Sleep Apnea Screening: Are We There Yet? A Systematic Review and Meta-analysis

BACKGROUND

Perioperative diagnosis of obstructive sleep apnea (OSA) has important resource implications as screening questionnaires are overly sensitive, and sleep studies are expensive and time-consuming. Ultrasound (US) is a portable, noninvasive tool potentially useful for airway evaluation and OSA screening in the perioperative period. The objective of this systematic review was to evaluate the correlation of surface US with OSA diagnosis and to determine whether a point-of-care ultrasound (PoCUS) for OSA screening may help with improved screening in perioperative period.

METHODS

A search of all electronic databases including Medline, Embase, and Cochrane Database of Systematic Reviews was conducted from database inception to September 2017. Inclusion criteria were observational cohort studies and randomized controlled trials of known or suspected OSA patients undergoing surface US assessment. Article screening, data extraction, and summarization were conducted by 2 independent reviewers with ability to resolve conflict with supervising authors. Diagnostic properties and association between US parameters (index test) and OSA diagnosis using sleep study (reference standard) were evaluated. The US parameters were divided into airway and nonairway parameters. A random-effects meta-analysis was planned, wherever applicable.

RESULTS

Of the initial 3865 screened articles, 21 studies (7 airway and 14 nonairway) evaluating 3339 patients were included. Majority of studies were conducted in the general population (49%), respirology (23%), and sleep clinics (12%). No study evaluated the use of US for OSA in perioperative setting. Majority of included studies had low risk of bias for reference standard and flow and timing. Airway US parameters having moderate-good correlation with moderate-severe OSA were distance between lingual arteries (DLAs > 30 mm; sensitivity, 0.67; specificity, 0.59; 1 study/66 patients); mean resting tongue thickness (>60 mm; sensitivity, 0.85; specificity, 0.59; 1 study/66 patients); tongue base thickness during Muller maneuver (MM; sensitivity, 0.59; specificity, 0.78; 1 study/66 patients); and a combination of neck circumference and retropalatal (RP) diameter shortening during MM (sensitivity, 1.0; specificity, 0.65; 1 study/104 patients). Nonairway US parameters having a low-moderate correlation with moderate-severe OSA were carotid intimal thickness (pooled correlation coefficient, 0.444; 95% confidence interval [CI], 0.320-0.553; P value = .000, 8 studies/727 patients) and plaque presence (sensitivity, 0.24-0.75; specificity, 0.13-1.0; 4 studies/1183 patients).

CONCLUSIONS

We found that a number of airway and nonairway parameters were identified with moderate to good correlation with OSA diagnosis in the general population. In future studies, it remains to be seen whether PoCUS screening for a combination of these parameters can address the pitfalls of OSA screening questionnaires.

Risk Factors for Obstructive Sleep Apnea Syndrome in Children: State of the Art

The obstructive sleep apnea syndrome (OSAS) represents only part of a large group of pathologies of variable entity called respiratory sleep disorders (RSD) which include simple snoring and increased upper airway resistance syndrome (UARS). Although the etiopathogenesis of adult OSAS is well known, many aspects of this syndrome in children are still debated. Its prevalence is about 2% in children from 2 to 8 years of age, mostly related to the size of the upper airways adenoid tissue. Several risk factors linked to the development of OSAS are typical of the pediatric age. The object of this paper is to analyze the state of the art on this specific topic, discussing its implications in terms of diagnosis and management.

Severity of Obstructive Sleep Apnea Is Positively Associated With the Presence of Carotid Artery Atheromas

PURPOSE

Hypoxemia and hypertension caused by obstructive sleep apnea (OSA) often result in atherosclerosis of the carotid and coronary vessels and heightened risk of stroke and myocardial infarction (MI). Therefore, this study investigated whether severity of OSA, based on the apnea-hypopnea index (AHI), is associated with the presence of calcified carotid artery (atherosclerotic) plaque (CCAP) seen on panoramic images (PIs).

MATERIALS AND METHODS

Using a cross-sectional study design, the electronic medical records and PIs of all male patients referred from the sleep medicine service to the dental service from 2010 through 2016 were reviewed. The predictor variable was the patients' OSA intensity level as defined by the American Academy of Sleep Medicine based on the AHI score. The outcome variable was the presence of CCAP on the PI. Other variables of interest, that is, demographic and atherogenic risk factors (age, body mass index, diabetes, hypertension, and hyperlipidemia), were included in a multivariate analysis to assess the association of OSA with CCAP.

RESULTS

The study sample consisted of 108 men (mean age, 54.7 ± 13.5 yr). Approximately one third (n = 33; 30.6%) presented with CCAP and this group was significantly older with greater odds of co-diagnosis of diabetes (P < .05). Patients with more "severe" OSA showed significantly greater odds of having CCAP on their PIs compared with those with "milder" OSA (odds ratio = 1.035; 95% confidence interval, 1.008-1.062; P = .010) when adjusted for confounders.

CONCLUSION

There is a significant association between severity of OSA and the presence of CCAP visible on PI. These atherosclerotic plaques are "risk factors" for stroke and "risk indicators" for future MI; therefore, clinicians providing corrective airway surgery for these patients and noting concomitant CCAP on PI should refer these patients for a thorough cerebrovascular and cardiovascular workup.

Carotid Artery Wall Thickness in Obese and Nonobese Adults With Obstructive Sleep Apnea Before and Following Positive Airway Pressure Treatment

Study objectives

Debate persists as to whether obstructive sleep apnea (OSA) is an independent risk factor for atherosclerosis. The purpose of this study was to compare carotid intima-media thickness (IMT), an early sign of atherosclerosis, in obese and nonobese adults with OSA before and following positive airway pressure (PAP) treatment.

Methods

A total of 206 adults newly diagnosed with OSA with an apnea-hypopnea index (AHI) of 15-75 events/hour and 53 controls with AHI <10 were studied. Waist circumference was used to classify participants as obese and nonobese. Bilateral common carotid artery B-mode ultrasound was performed at baseline to assess IMT, arterial diameter, arterial-wall mass, and circumferential wall stress. Measurements were repeated in 118 participants with OSA who completed a 4-month PAP treatment and had an average daily use over that period of ≥4 hours/day.

Results

No significant differences in carotid IMT, diameter, or arterial-wall mass were present at baseline between participants with OSA and controls stratified by waist circumference, after adjusting for other cardiovascular risk factors. In participants with OSA, who had adequate PAP adherence over the 4-month treatment, carotid artery diameter significantly increased (mean change [95% confidence interval] = 0.13 [0.06, 0.20] mm; p = .0004), but no significant changes in carotid IMT, arterial-wall mass, and circumferential stress were observed in obese and nonobese participants.

Conclusions

Regardless of obesity status, carotid IMT is not increased in adults with moderate to severe OSA versus controls and does not change following 4 months of PAP treatment.

[Long-term effects of continuous positive airway pressure treatment on subclinical atherosclerosis in obstructive sleep apnoea syndrome]

BACKGROUND AND OBJECTIVE

Obstructive sleep apnoea (OSA) is associated with an increased risk of cardiovascular disease. Our objective was to evaluate subclinical atherosclerosis in OSA patients and the effect of continuous positive airway pressure (CPAP) treatment on carotid intima-media thickness (cIMT).

PATIENTS AND METHOD

We included 125 patients with suspected OSA. After polysomnography, 107 patients were diagnosed with OSA; 58 of these met the criteria for CPAP treatment. cIMT was measured by ultrasonography at baseline in all patients and after 2 years of follow up in 50 patients on CPAP and 35 without CPAP treatment.

RESULTS

The average cIMT was significantly thicker in OSA than in non-OSA patients (665±120 vs. 581±78μm, P=.005) and did not differ according to OSA severity. Atheromatous carotid plaque was more prevalent in OSA than non-OSA patients (48 vs. 2%, P=.004). Among OSA patients, the mean cIMT remained stable over time in the group without CPAP, whereas cIMT decreased markedly in the CPAP group (679±122 vs. 631±117μm, P<.0001).

CONCLUSIONS

Increased cIMT was associated with presence of OSA, but not with its severity. Carotid ultrasound in OSA is a reliable marker of atherosclerosis. CPAP treatment with CPAP in OSA reduces cIMT and cardiovascular risk.

Estradiol Regulates Txnip and Prevents Intermittent Hypoxia-Induced Vascular Injury

Chronic intermittent hypoxia (IH) contributes to obstructive sleep apnea (OSA)-related cardiovascular diseases through increasing oxidative stress. It has been widely recognized that estradiol decreases the risk for cardiovascular disease, but the estrogen replacement therapy is limited for its side effects. Thioredoxin (Trx) and its endogenous inhibitor, thioredoxin-interacting protein (Txnip), are associated with the protective effect of estradiol in some conditions. In this study, we aimed to explore whether estradiol could protect against IH-induced vascular injury, and the possible effect of Trx-1/Txnip in this process. Forty-eight adult female C57/BL6J mice were randomly divided into 4 groups, ovariectomy combined with IH group, sham operation combined with IH group, IH group and the control group. The mice treated with IH for 8 hrs/day, and 28 days. IH induced the injury of aorta, and ovariectomized mice were more prone to the IH-induced aortic injury, with higher level of oxidative stress. In vitro, estradiol increased Trx-1 level, but decreased the level of Txnip and oxidative stress in human umbilical vein endothelial cells (HUVECs) treated with IH for 16 hrs. Knock-down of Txnip by specific siRNA rescued oxidative stress and apoptosis. In conclusion, estradiol protects against IH-induced vascular injury, partially through the regulation of Trx-1/Txnip pathway.

Does Cardiovascular Comorbidity Influence the Prescribing of Bronchodilators in Chronic Obstructive Pulmonary Disease?

BACKGROUND

Cardiovascular disease (CVD) is the most prevalent comorbidity for chronic obstructive pulmonary disease (COPD). Potential adverse cardiovascular events of bronchodilators warrant their cautionary use in the comorbid COPD-CVD population, yet little is known about the prescribing of bronchodilators in this high-risk patient group.

OBJECTIVE

To determine whether comorbid CVD is associated with reduced bronchodilator prescribing in patients with COPD. In addition, we explored how the association was modified by gender, concurrent asthma, and concomitant β-blocker (BB) use.

METHODS

A cross-sectional study was conducted using the 2010 National Ambulatory Medical Care Survey. All visits among diagnosed COPD patients 40 years and older were examined. Logistic regression on survey-weighted data was used to predict treatment with bronchodilators and determine the influence of gender, asthma, and BBs on bronchodilator prescribing.

RESULTS

Among 11 627 061 ambulatory COPD visits, we found a significantly lower bronchodilator treatment rate among patients with comorbid CVD (32.3%) than among patients without CVD (57.6%). The observed effect was modified by gender, asthma, and BBs. Deprescribing was more pronounced for females than males, for nonusers of BBs than users of BBs, and for asthma patients than nonasthma patients. CVD did not affect bronchodilator prescribing in either asthmatic or nonasthmatic males taking BBs.

CONCLUSIONS

Most COPD patients with concurrent CVD were less likely to be prescribed bronchodilators, with the exception of males who were also prescribed BBs. Thus, this study highlights a specific patient subgroup for whom the guidelines are less likely to be observed.

Potential inflammatory markers in obstructive sleep apnea-hypopnea syndrome

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a complex chronic inflammatory respiratory disease with multiple pathogenic factors and high morbidity and mortality. Serum levels of nuclear factor-κB (NF-κB), hypoxia-inducible factor-1 alpha (HIF-1α), and surfactant protein D (SPD) were investigated in OSAHS patients, to determine their clinical significance and correlation with the pathogenesis. Patients were classified into a mild and moderate OSAHS group (n = 25) and severe OSAHS group (n = 33). Twenty healthy patients served as a control group. Peripheral blood levels of NF-κB, HIF-1α, and SPD were determined by Western blot, and a correlation analysis was performed. Severe OSAHS patients received nasal continuous positive airway pressure (nCPAP) therapy and were followed up after 2 months. NF-κB p65, HIF-1α, and SPD expression levels were determined after valid nCPAP therapy. NF-κB p65 and HIF-1α expression was significantly higher in severe OSAHS group than in the other two groups (p < 0.01), and was positively correlated with the apnea-hypopnea index (AHI) (r = 0.696, p < 0.001; r = 0.634, p < 0.001). SPD expression was significantly lower in severe OSAHS group than in the control group (p < 0.01) and mild and moderate OSAHS group (p < 0.01), and was negatively correlated with AHI (r = -0.569, p < 0.001). OSAHS pathogenesis was associated with changes in NF-κB, HIF-1α, and SPD protein expression levels. nCPAP therapy could improve the clinical characteristics of the patients, lower serum NF-κB and HIF-1α levels, and increase serum SPD levels. We conclude that OSAHS is related to the expression of NF-κB, HIF-1, and SPD.

Assessment of carotid artery intima-media thickness in patients with obstructive sleep apnoea

OBJECTIVE

This study compares the carotid intima-media thickness (CIMT) in different severity of obstructive sleep apnoea (OSA) patients and assesses the role of OSA in carotid artery vasculopathy with control of multiple co-morbidities.

STUDY DESIGN

Prospective case-control study.

SETTING

Tertiary referral centre.

PARTICIPANTS

This study recruited 36 volunteers without the complaints of sleep-disordered breathing, 27 patients with mild-moderate OSA and 39 patients with severe OSA.

MAIN OUTCOME MEASURES

The CIMT was measured using a Toshiba Aplio 500 ultrasound system (Otawara, Japan) with a 5-14 MHz L probe.

RESULTS

Bilateral and mean CIMT in healthy control, mild-moderate OSA and severe OSA were 0.69 ± 0.14, 0.72 ± 0.24 and 0.94 ± 0.33, respectively (P < 0.01 in anova test). Post hoc tests show that the severe OSA group had significantly higher mean CIMT than the control and mild-moderate OSA groups (P < 0.01). With the cut-off as 1 mm, the increased risks of cardiovascular disease (CVD) for mild-moderate and severe OSA were 11% and 39%, respectively, while no patient in the healthy control group was at risk of CVD. Multivariate linear regression could not prove that OSA itself was an independent factors for increased CIMT (mild-moderate OSA β: 0, [-0.12, 0.13]; severe OSA β: 0.08, [-0.06, 0.22], both P > 0.05) after adjusting age, hypertension and body mass index.

CONCLUSION

Automated measurement of the CIMT can be a useful tool for CVD risk assessment in patients with OSA. Severity of OSA may be an intermediate factor between multiple co-morbidities and carotid atherosclerotic change.

Subclinical atherosclerosis risk markers in patients with chronic obstructive pulmonary disease: A systematic review and meta-analysis

BACKGROUND AND AIMS

Chronic obstructive pulmonary disease (COPD) is associated with increased cardiovascular morbidity and mortality. Identifying early changes of cardiovascular system before the occurrence of fatal clinical event is critical for the management of COPD. We performed a meta-analysis to investigate the associations between COPD and subclinical markers of cardiovascular risk.

METHODS

We searched PUBMED, EMBASE for studies published before Aug 1st, 2016, on the association between COPD and carotid intima-media thickness (CIMT), prevalence of carotid plaques, flow-mediated dilation (FMD), pulse-wave velocity (PWV) and augmentation index (AIx).

RESULTS

Thirty-two studies (3198 patients, 13867 controls) were included. Compared with controls, COPD patients had significantly higher CIMT (MD: 0.10 mm; 95% CI: 0.04, 0.16; p = 0.0007), PWV (SMD: 0.70; 95% CI: 0.52, 0.88; p < 0.0001), AIx (MD: 4.60%; 95% CI: 0.52, 8.68; p = 0.03), AIx@75 (AIx normalized to a heart rate of 75 beats per minute) (MD: 4.59%; 95% CI: 2.80, 6.38; p < 0.0001), prevalence of carotid plaque (OR: 2.54; 95% CI: 2.04, 3.15; p < 0.0001), and significantly lower FMD (MD: -4.21%; 95% CI: -6.71, -1.71; p = 0.001). Sensitivity and subgroups analyses substantially confirmed our results. Meta-regression analysis revealed that spirometry (as expressed by FEV₁%predicted) might influence on PWV.

CONCLUSIONS

These findings indicate that COPD, even in mild to moderate patients, had greater impaired markers of subclinical atherosclerosis and cardiovascular risk. However, further studies are still needed to address confounders, such as age, smoking, hypertension, diabetes etc, which might affect the associations in COPD patients.

Efficacy of nasal continuous positive airway pressure on patients with OSA with erectile dysfunction and low sex hormone levels

PURPOSE

This study aimed to test the hypothesis that erectile dysfunction (ED) is common in men with obstructive sleep apnea (OSA). We also assessed the efficacy of continuous positive airway pressure (CPAP) treatment for ED and sex hormone levels in patients with severe OSA and ED.

METHODS

A total of 153 OSA patients and 60 healthy controls were enrolled in this study. The International Index of Erectile Dysfunction-5 (IIEF-5) score was obtained, and blood samples were collected for analysis of sex hormones after polysomnography. The IIEF-5 score, sex hormone levels, and polysomnographic parameters were re-evaluated in 32 patients with severe OSA and ED after 1 month of CPAP treatment.

RESULTS

The present study showed that the prevalence of ED was 47.1% in all cases and only 13.3% in controls, and a lower sex hormone levels was presented in OSA patients. OSA patients with ED had greater severity of disease, and lower serum levels of follicle stimulating hormone (FSH) and testosterone than OSA patients without ED (p < 0.05). After CPAP therapy, there was a significant increase in the IIEF-5 score, and serum levels of FSH, luteinizing hormone, and testosterone, were elevated compared with baseline levels (p < 0.05). Multivariate regression analysis indicated the serum level of testosterone had impact on the ED.

CONCLUSIONS

OSA patients had lower sex hormone levels and a higher occurrence of ED than controls, and serum level of testosterone had effect on ED. CPAP treatment ameliorated the symptoms of ED and elevated serum levels of FSH, luteinizing hormone, and testosterone.

The effect of obstructive sleep apnea syndrome and hypothyroidism to intima-media thickness of carotid artery

AIM

Obstructive sleep apnea syndrome (OSAS) is a common disorder and in subjects with OSAS the prevalence of hypothyroidism is approximately 1.2-11 %. The episodes of hypoxia/reoxygenation associated with the respiratory disturbances observed in subjects with OSAS increases the risk of cardiovascular diseases. Hypothyroidism; primary or subclinical, has several effects on cardiovascular system. In our study, we investigated carotid artery intima-media thickness (IMT) which is an early sign of atherosclerosis, in OSAS subjects with hypothyroidism.

MATERIALS AND METHOD

Subjects who admitted to Kahramanmaras Necip Fazıl City State Hospital Chest Diseases out-patient clinic between May 2014 and January 2016 for snoring and had polysomnographic evaluation at the sleep laboratory were included in this study. Each subject was evaluated for serum thyroid function tests and carotid artery IMT was measured by a Doppler ultrasound.

RESULTS

Mean carotid artery IMT values in the isolated OSAS, OSAS plus hypothyroidism, and control groups were 0.67 ± 0.12, 0.8 ± 0.12, and 0.54 ± 0.08 mm, respectively; difference between groups was statistically significant (p < .05). A poXsitive correlation was found between thyroid stimulating hormone levels and IMT (r = 0.426, p = .002), while free T3 levels and IMT were negatively correlated (r = -0.463, p = .001). IMT and apnea-hypopnea index were also positively correlated (r = 0.403, p = .003).

CONCLUSION

We suggest, physicians should be alert for hypothyroidism comorbidity in OSAS, and suspected subjects with OSAS should be screened for hypothyroidism considering the potential cardiovascular complications.

Influence of obstructive sleep apnea on ischemia-modified albumin levels and carotid intima-media thickness

Obstructive sleep apnea (OSA) is associated with an increased risk of atherosclerosis. Carotid intima-media thickness (CIMT) is strongly associated with the presence of significant risk factors for cardiovascular disturbances. A disturbance in the oxidative/antioxidative balance is involved in the pathogenesis of OSA and cardiovascular diseases. Ischemia-modified albumin (IMA) is suggested as a novel marker of oxidative stress; IMA can be defined as decreased binding of transitional metal ions to serum albumin in oxidative status. The purpose of this research was to evaluate the influence of OSA on IMA levels and CIMT. In total, 61 individuals with OSA with no comorbidities and 24 healthy controls with a similar body mass index and age were enrolled in this study. Serum levels of IMA, CIMT (estimated radiologically), and polysomnographic parameters, were determined and interpreted. Serum IMA levels were significantly higher in individuals with OSA compared with the control group (p=0.0003). CIMT was significantly higher in the OSA group compared with the control group (0.88± 0.26 mm vs 0.75±0.17 mm, p=0.005). The CIMT and serum IMA levels were positively correlated with the apnea-hypopnea index (r=0.35 and r=0.32, respectively), and with the oxygen desaturation index (r=0.34 and r=0.29, respectively) at baseline. Increased IMA levels and CIMT may be related to increased oxidative stress and risk of atherosclerosis in individuals with OSA.

Antioxidant Carbocysteine Treatment in Obstructive Sleep Apnea Syndrome: A Randomized Clinical Trial

Objective

This study aimed to examine the effects of carbocysteine in OSAS patients.

Methods

A total of 40 patients with moderate to severe obstructive sleep apnea syndrome (OSAS) were randomly divided into two groups. One group was treated with 1500 mg carbocysteine daily, and the other was treated with continuous positive airway pressure (CPAP) at night. Before treatment and after 6 weeks of treatment, all patients underwent polysomnography and completed questionnaires. Treatment compliance was compared between the two groups. Plasma was collected for various biochemical analyses. Endothelial function was assessed with ultrasound in the carbocysteine group.

Results

The proportion of patients who fulfilled the criteria for good compliance was higher in the carbocysteine group (n = 17) than in the CPAP group (n = 11; 100% vs. 64.7%). Compared with baseline values, the carbocysteine group showed significant improvement in their Epworth Sleepiness Scale score (10.18±4.28 vs. 6.82±3.66; P≤0.01), apnea-hypopnea index (55.34±25.03 vs. 47.56±27.32; P≤0.01), time and percentage of 90% oxygen desaturation (12.66 (2.81; 50.01) vs. 8.9 (1.41; 39.71); P≤0.01), and lowest oxygen saturation level (65.88±14.86 vs. 70.41±14.34; P≤0.01). Similar changes were also observed in the CPAP group. The CPAP group also showed a decreased oxygen desaturation index and a significant increase in the mean oxygen saturation after treatment, but these increases were not observed in the carbocysteine group. Snoring volume parameters, such as the power spectral density, were significantly reduced in both groups after the treatments. The plasma malondialdehyde level decreased and the superoxide dismutase and nitric oxide levels increased in both groups. The endothelin-1 level decreased in the CPAP group but did not significantly change in the carbocysteine group. Ultrasonography showed that the intima-media thickness decreased (0.71±0.15 vs. 0.66±0.15; P≤0.05) but that flow-mediated dilation did not significantly change in the carbocysteine group.

Conclusions

Oral carbocysteine slightly improves sleep disorders by attenuating oxidative stress in patients with moderate to severe OSAS. Carbocysteine may have a role in the treatment of OSAS patients with poor compliance with CPAP treatment. However, the efficiency and feasibility of carbocysteine treatment for OSAS needs further evaluation.

Trial Registration

ClinicalTrials.gov NCT02015598

Association between Plaque Score of the Carotid Artery and the Severity of Sleep Apnea Syndrome in Patients with Chronic Kidney Disease

BACKGROUND

Recently, sleep apnea syndrome (SAS) has been associated with hypertension, cardiovascular disease and death. Patients with chronic kidney disease (CKD) have higher rates of SAS, atherosclerotic complications and death than do patients without CKD. Although the relationship between SAS and atherosclerosis is well known, few papers have described this relationship in humans, especially in CKD patients.

PATIENTS AND METHODS

This was a cross-sectional study of 110 clinically stable, non-dialysis patients with CKD who attended a CKD educational program from April 2014 to September 2015. The diagnosis of SAS and its severity were assessed using a type 3 portable monitor. Other atherosclerosis-related data were obtained from the patients' medical records in order to determine the factors associated with the severity of SAS.

RESULTS

95 men and 15 women with a mean age of 71.4 ± 9.9 years were included in the study. The patients' mean body mass index was 24.0 ± 3.9, their mean blood pressure 134.3 ± 21.2/73.6 ± 13.4 mm Hg and their mean estimated glomerular filtration rate 19.8 ± 9.5 ml/min/1.7 m(2). Adjusted plaque score was a significant predictor of severe SAS (odds ratio = 1.13, p = 0.0182). Mixed plaque was significantly associated with severe SAS (correlation ratio = 0.48, p < 0.0001).

CONCLUSIONS

Many patients with CKD also have SAS. Our findings demonstrate the relationship between plaque score and the severity of SAS.

Cerebrovascular reactivity and neurovascular coupling in patients with obstructive sleep apnea

AIM

Obstructive sleep apnea syndrome (OSAS) has been implicated as an independent risk factor for stroke. There are data suggesting the presence of lower cerebrovascular reactivity (CVR) as determined by transcranial Doppler (TCD) in patients with OSAS. We concurrently investigated neurovascular coupling (NVC) with visual stimulation, and CVR using breath-holding (BH) test on TCD in patients with OSAS.

MATERIALS AND METHODS

Data were collected in 49 patients with moderate to severe OSAS, and compared to 15 healthy subjects matched for age and risk factors. The CVR to hypercapnia was measured by BH test, and the NVC was performed with visual stimulation.

RESULTS

There were no significant differences in baseline characteristics of patients and controls, except for BMI, which was significantly higher in patients with OSAS (p = 0.036). OSAS patients showed significantly lower reactivity during BH in comparison to controls (36.9% ± 14.0% vs. 46.6% ± 20.1%; p = 0.019). The reactivity time was also significantly shorter in the OSAS group (8.0 ± 4.2 s) when compared to controls (10.1 ± 4.3 s; p = 0.015). The visual stimulation produced similar reactivity in patients (27.7% ± 9.4%) and controls (29.1 ± 13.9; p > 0.05).

CONCLUSIONS

Our data demonstrate a diminished vasodilator response capacity only to a strong stimulator such as hypercapnia in OSAS patients. However, the NVC, as shown by the TCD, is quite normal, suggesting that a weak or mild stimulation produces a proper reactivity among OSAS patients.

Obstructive Sleep Apnea, Hypertension, and Their Additive Effects on Atherosclerosis

Background and Aims. It is widely accepted that obstructive sleep apnea (OSA) is independently associated with atherosclerosis. Similar to OSA, hypertension (HTN) is a condition associated with atherosclerosis. However, to date, the impact of the simultaneous presence of OSA and HTN on the risk of atherosclerosis has not been extensively studied. The aim of this study was to evaluate the consequences of the coexistence of OSA and HTN on carotid intima-media thickness (IMT) and on inflammatory markers of atherosclerosis (such as interleukin- [IL-] 6 and pentraxin- [PTX-] 3). Methods. The study design allowed us to define 4 groups: (1) controls (n = 30); (2) OSA patients without HTN (n = 30); (3) HTN patients without OSA (n = 30); (4) patients with OSA and HTN (n = 30). In the morning after portable monitoring (between 7 am and 8 am), blood samples were collected, and carotid IMT was measured. Results. Carotid IMT, IL-6, and PTX-3 in OSA normotensive patients and in non-OSA HTN subjects were significantly higher compared to control subjects; in addition, in OSA hypertensive patients they were significantly increased compared to OSA normotensive, non-OSA HTN, or control subjects. Conclusions. OSA and HTN have an additive role in the progression of carotid atherosclerosis and in blood levels of inflammatory markers for atherosclerosis, such as interleukin-6 and pentraxin-3.

Endothelial Progenitor Cells Predict Cardiovascular Events after Atherothrombotic Stroke and Acute Myocardial Infarction. A PROCELL Substudy

Introduction

The aim of this study was to determine prognostic factors for the risk of new vascular events during the first 6 months after acute myocardial infarction (AMI) or atherothrombotic stroke (AS). We were interested in the prognostic role of endothelial progenitor cells (EPC) and circulating endothelial cells (CEC)

Methods

Between February 2009 and July 2012, 100 AMI and 50 AS patients were consecutively studied in three Spanish centres. Patients with previously documented coronary artery disease or ischemic strokes were excluded. Samples were collected within 24h of onset of symptoms. EPC and CEC were studied using flow cytometry and categorized by quartiles. Patients were followed for up to 6 months. NVE was defined as new acute coronary syndrome, transient ischemic attack (TIA), stroke, or any hospitalization or death from cardiovascular causes. The variables included in the analysis included: vascular risk factors, carotid intima-media thickness (IMT), atherosclerotic burden and basal EPC and CEC count. Multivariate survival analysis was performed using Cox regression analysis.

Results

During follow-up, 19 patients (12.66%) had a new vascular event (5 strokes; 3 TIAs; 4 AMI; 6 hospitalizations; 1 death). Vascular events were associated with age (P = 0.039), carotid IMT≥0.9 (P = 0.044), and EPC count (P = 0.041) in the univariate analysis. Multivariate Cox regression analysis showed an independent association with EPC in the lowest quartile (HR: 10.33, 95%CI (1.22–87.34), P = 0.032] and IMT≥0.9 [HR: 4.12, 95%CI (1.21–13.95), P = 0.023].

Conclusions

Basal EPC and IMT≥0.9 can predict future vascular events in patients with AMI and AS, but CEC count does not affect cardiovascular risk.

Sleep apnea is independently associated with peripheral arterial disease in the Hispanic Community Health Study/Study of Latinos

OBJECTIVE

Sleep apnea (SA) has been linked with various forms of cardiovascular disease, but little is known about its association with peripheral artery disease (PAD) measured using the ankle-brachial index. This relationship was evaluated in the Hispanic Community Health Study/Study of Latinos.

APPROACH AND RESULTS

We studied 8367 Hispanic Community Health Study/Study of Latinos participants who were 45 to 74 years of age. Sleep symptoms were examined with the self-reported Sleep Health Questionnaire. SA was assessed using an in-home sleep study. Systolic blood pressure was measured in all extremities to compute the ankle-brachial index. PAD was defined as ankle-brachial index <0.90 in either leg. Multivariable logistic regression was used to investigate the association between moderate-to-severe SA, defined as apnea-hypopnea index ≥15, and the presence of PAD. Analyses were adjusted for covariates. The prevalence of PAD was 4.7% (n=390). The mean apnea-hypopnea index was significantly higher among adults with PAD compared with those without (11.1 versus 8.6 events/h; P=0.046). After adjusting for covariates, moderate-to-severe SA was associated with a 70% increase in the odds of PAD (odds ratio, 1.7; 95% confidence interval, 1.1-2.5; P=0.0152). This association was not modified by sex (P=0.8739). However, there was evidence that the association between moderate-to-severe SA and PAD varied by Hispanic/Latino background (P<0.01). Specifically, the odds were stronger in Mexican (adjusted odds ratio, 2.9; 95% confidence interval, 1.3-6.2) and in Puerto Rican Americans (adjusted odds ratio, 2.0; 95% confidence interval, 0.97-4.2) than in other backgrounds.

CONCLUSIONS

Moderate-to-severe SA is associated with higher odds of PAD in Hispanic/Latino adults.

The correlation between red blood cell distribution width levels with the severity of obstructive sleep apnea and carotid intima media thickness

Background

Obstructive sleep apnea syndrome (OSAS) is characterized by repetitive collapse of the upper airway during sleep. Red blood cell distribution width (RDW) increases platelet activation and has been reported as an independent predictor of adverse outcomes in the general population and is believed to be associated with cardiovascular morbidity and mortality. We evaluated RDW, mean platelet volume (MPV), and platelet distribution width (PDW) as a severity index in OSAS and the relationship between carotid intima media thickness and pulmonary hypertension.

Material/Methods

The study population consisted of 99 patients who were admitted to the sleep laboratory. Based on the apnea-hypopnea index, patients were grouped into 3 OSAS severity categories. Morning blood samples were withdrawn from patients after a 12-hour fasting period. MPV, PDW, and RDW were measured in a blood sample. Bilateral common carotid arteries of the patients were scanned.

Results

Ninety-nine patients – 73 with OSAS and 26 simple snoring control cases – were included. Mean values of MPV, PDW, and RDW were similar in patients compared to simple snoring subjects in the control group (p=0.162, p=0.656, p=0.091). RDW showed an inverse correlation with mean desaturation and lowest desaturation (p<0.01). Body mass index, apnea-hypopnea index, pulmonary artery pressure, and desaturation time under 90% were positively correlated with RDW (p<0.05). MPV, PDW, and carotid intima media thickness had no correlation with any other parameters.

Conclusions

The study showed a positive relationship between RDW and the apnea-hypopnea index and systolic pulmonary hypertension in patients with OSAS.

Obstructive sleep apnea is associated with future subclinical carotid artery disease: thirteen-year follow-up from the Wisconsin sleep cohort

OBJECTIVE

To determine the longitudinal associations between obstructive sleep apnea, carotid artery intima-media thickness (IMT), and plaque.

APPROACH AND RESULTS

This is a population-based, prospective cohort study conducted from July, 1989, to November, 2012, on 790 randomly selected Wisconsin residents who completed a mean of 3.5 (range, 1-6) polysomnograms during the study period. Obstructive sleep apnea was characterized by the apnea-hypopnea index (AHI, events/h). Common carotid artery IMT and plaque were assessed by B-mode ultrasound. The mean (SD) time from the first polysomnograms to carotid ultrasound was 13.5 (3.6) years. Multivariable regression models were created to estimate the independent associations of baseline and cumulative obstructive sleep apnea exposure with subsequent carotid IMT and plaque. At baseline, the mean age of participants was 47.6 (7.7) years (55% men, 97% white). AHI was 4.4 (9.0) events/h (range, 0-97); 7% had AHI >15 events/h. Carotid IMT was 0.755 (0.161) mm; 63% had plaque. Adjusting for age, sex, body mass index, systolic blood pressure, smoking, and use of lipid-lowering, antihypertensive, and antidiabetic medications, baseline AHI independently predicted future carotid IMT (β=0.027 mm/unit log10[AHI+1]; P=0.049), plaque presence (odds ratio, 1.55 [95% confidence intervals, 1.02-2.35]; P=0.041) and plaque score (odds ratio, 1.30 [1.05-1.61]; P=0.018). In cumulative risk factor-adjusted models, AHI independently predicted future carotid plaque presence (P=0.012) and score (P=0.039), but not IMT (P=0.608).

CONCLUSIONS

Prevalent obstructive sleep apnea is independently associated with increased carotid IMT and plaque more than a decade later, indicating increased future cardiovascular disease risk.

Pilot study of the effects of bariatric surgery and continuous positive airway pressure treatment on vascular function in obese subjects with obstructive sleep apnoea

BACKGROUND

The mechanisms by which obesity and obstructive sleep apnoea (OSA) may contribute to endothelial dysfunction are unclear.

AIMS

We sought to follow up a sample of obese subjects undergoing either bariatric surgery or continuous positive airway pressure (CPAP) therapy to treat OSA. We hypothesised improved vascular function with both therapeutic approaches, consistent with a reversible OSA effect on the circulation.

METHODS

Twenty-seven obese (BMI ≥30 kg/m(2)) subjects with OSA underwent either bariatric surgery without CPAP (n = 12, median BMI 43.7 kg/m(2) IQR 9.4) or CPAP (n = 15, median BMI 33.8 kg/m(2) IQR 6.6). Polysomnography and vascular testing (flow-mediated dilation of the brachial artery measured with high-resolution ultrasound, endothelium-dependent change in skin blood flow measured with laser Doppler flowmetry, and arterial stiffness measured with applanation tonometry) took place at baseline and after 6 months.

RESULTS

Both groups showed significant improvements in the apnoea-hypopnea index and overnight oxygen saturation. Endothelium-dependent microvascular reactivity was 45.6% (IQR 37.5) at baseline in the CPAP group, which increased to 69.1% (IQR 62.3) post-treatment (P < 0.05). No significant changes were observed in the surgery group, despite significant weight loss (post-surgery BMI 32.7 kg/m2 IQR 8.6 (P < 0.01); no change in BMI was observed in the CPAP group. There were no significant changes in brachial artery flow-mediated dilation in either group.

CONCLUSIONS

This pilot study demonstrates that 6 months of CPAP may be sufficient to improve endothelium-dependent microvascular reactivity, while substantial surgically induced weight loss did not result in improvements. Further research should be directed towards comparative effectiveness trials using these novel surrogate outcomes, as well as hard cardiovascular outcomes.

Systematic review on noninvasive assessment of subclinical cardiovascular disease in obstructive sleep apnea: new kid on the block!

Patients with obstructive sleep apnea (OSA) have a high burden of cardiovascular disease (CVD) but a causal relationship between OSA and atherosclerotic CVD remains unclear. We systematically reviewed the literature analyzing the relationship. A review of the Medline database for studies noninvasively evaluating subclinical CVD in OSA was conducted. A total of fifty-two studies were included in this review. Across the studies the prevalence of atherosclerosis, as assessed by coronary artery calcification, carotid intima-media thickness, brachial artery flow-mediated dilation and pulse wave velocity was higher in patients with OSA and correlated with increasing severity and duration of OSA. This study shows OSA is an independent predictor of subclinical CVD as CVD is more likely to occur in patients with long standing and severe OSA. Further research is however necessary to identify specific OSA populations that would benefit from aggressive screening.

Correlation between inflammatory markers of atherosclerosis and carotid intima-media thickness in Obstructive Sleep Apnea

Obstructive Sleep Apnea (OSA) is a sleep-related breathing disorder associated with the development of cardiovascular diseases and atherosclerosis. Systemic inflammation plays an important role in the development of cardiovascular complications in OSA patients. The aim of the study was to evaluate the relationship between carotid intima-media thickness (cIMT) and inflammatory markers plasma levels in OSA patients. We enrolled 80 OSA patients and 40 controls matched for age and body mass index (BMI). The presence and severity of sleep apnea was determined by in-laboratory portable monitoring (PM). Demographic data, blood pressure, heart rate, and cIMT were measured. High-sensitive C-Reactive Protein (hsCRP), interleukin (IL)-6, tumor necrosis factor (TNF)-α and pentraxin (PTX)-3 serum concentrations were detected. cIMT was higher in OSA patients than controls (0.89 ± 0.13 mm vs. 0.65 ± 0.1 mm, p < 0.01). Moderate-severe OSA patients (0.95 ± 0.09 mm) had significantly increased cIMT than mild OSA (0.76 ± 0.1 mm; p < 0.01) and control (0.65 ± 0.1 mm; p < 0.01). hsCRP, IL-6, TNF-α, and PTX-3 in patients with OSA (1.67 ± 0.66 mg/L, 2.86 ± 1.39 pg/mL, 20.09 ± 5.39 pg/mL, 2.1 ± 0.59 ng/mL, respectively) were significantly higher than in controls (1.08 ± 0.53 mg/L, p < 0.01; 1.5 ± 0.67 pg/mL, p < 0.01; 12.53 ± 3.48 pg/mL, p < 0.01; 1.45 ± 0.41 ng/mL, p < 0.01, respectively). Carotid IMT was significantly correlated to CRP (r = 0.44; p < 0.01), IL-6 (r = 0.42; p < 0.01), TNF-α (r = 0.53; p < 0.01), and PTX-3 (r = 0.49; p < 0.01). OSA patients showed increased cIMT, CRP, IL-6, TNF-α, and PTX-3 levels. Inflammatory markers levels are correlated to cIMT in OSA patients.

Correlation between the intima-media thickness and Framingham risk score in patients with sleep apnea syndrome

BACKGROUND

In the present study, we want to demonstrate the correlation between obstructive sleep apnea syndrome (OSAS) whose independent effect on carotid artery intima-media thickness (IMT) was demonstrated, with Framingham risk score (FRS) showing the overall cardiovascular risk.

METHODS

IMT of the carotid artery was measured with ultrasonography and 10-year risk of coronary heart disease (CHD) was defined with FRS in 90 consecutive patients referred to our sleep clinic and who underwent polysomnography (PSG), with vascular risk factors and without a clinical atherosclerotic disease.

RESULTS

IMT and FRS were found to be statistically significantly increased in the severe OSAS group compared to the other two groups. Carotid IMT was found to be significantly positively correlated with, apnea-hypopnea index (AHI), oxygen desaturation index (ODI) and time duration with oxygen saturation (SpO2) <90%, and negatively correlated with minimum oxygen saturation at sleep (minimum SpO2) and mean SpO2. In control and mild OSAS group IMT and FRS have significantly positive correlation (r: 0.501, P: 0.027; r: 0.625, P<0.001), while in severe OSAS group no significant correlation was detected between IMT and FRS (r: 0.321, P: 0.06). In the regression analysis AHI and ODI were found to be an independent predictor of carotid IMT. ODI was found to have an independent effect on the progression of atherosclerosis.

CONCLUSIONS

Increased carotid IMT in severe OSAS group could not be explained with the classical risk factors. In this respect, FRS might be insufficient to determine correctly the cardiovascular risk and protection strategies against the disease in OSAS patients.

Associations of objectively measured and self-reported sleep duration with carotid artery intima media thickness among police officers

BACKGROUND

We aimed to examine the association of objectively measured and self-reported sleep duration with carotid artery intima media thickness (IMT) among 257 police officers, a group at high risk for cardiovascular disease (CVD).

METHODS

Sleep duration was estimated using actigraphic data and through self-reports. The mean maximum IMT was the average of the largest 12 values scanned bilaterally from three angles of the near and far wall of the common carotid, bulb, and internal carotid artery. Linear and quadratic regression models were used to assess the association of sleep duration with IMT.

RESULTS

Officers who had fewer than 5 or 8 hr or more of objectively measured sleep duration had significantly higher maximum IMT values, independent of age. Self-reported sleep duration was not associated with either IMT measure.

CONCLUSION

Attainment of sufficient sleep duration may be considered as a possible strategy for atherosclerosis prevention among police officers.

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

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