Endothelial dysfunction and inflammatory reactions of elderly and middle-aged men with obstructive sleep apnea syndrome

A comparison of the outcomes of tonsillectomy and expansion sphincter pharyngoplasty operations in patients with obstructive sleep apnea

OBJECTIVE

To compare the efficacy of tonsillectomy and expansion sphincter pharyngoplasty (ESP) in the surgical treatment of obstructive sleep apnea (OSA).

METHODS

OSA patients with Friedman grade III-IV tonsil hypertrophy diagnosed with polysomnography were separated into two groups according to the surgery performed, as the classic tonsillectomy group (Group 1) and the ESP group (Group 2). The primary endpoint of the study was to determine the Apnea-Hypopnea Index (AHI) value.

RESULTS

Group 1 comprised 24 patients with median preoperative AHI of 19.7 and postoperative AHI of median 11.8 (p = .0001). Group 2 comprised 29 patients with median preoperative AHI of 25.1 and postoperative AHI of median 16.3 (p = .0001). Nine (37.5%) of the 24 patients in Group 1 accepted as cure (79.1%). Eight (27.5%) of the 29 patients in Group 2 accepted as cure (72.4%).

CONCLUSION

There was no superiority of ESP over tonsillectomy in patients with lateral pharyngeal obstruction.

Association of time-varying sleep duration and cognitive function with mortality in the elderly: a 12-year community-based cohort study

BACKGROUND

Sleeping problems and cognitive impairment are common in elders. Baseline sleep duration and cognitive status are predictors of mortality. But few studies have explored whether longitudinal changes in sleep duration and cognitive function are related to mortality in older adults. The present study investigated the time-varying relationships of sleep duration and cognitive function with subsequent mortality among community-dwelling elders by using 12 years of repeated-measure data.

METHODS

Taichung Community Health Study for Elders (TCHS-E) is a retrospective, population-based cohort that started in 2009 (wave 1) with a total of 912 elders aged 65 years or above. Follow up was conducted in 2010 (wave 2), 2018 (wave 3), and 2020 (wave 4). Sleep duration and Mini-Mental State Examination (MMSE) forms were executed at baseline and three visits during follow-up. Time-varying Cox proportional hazards regression estimated adjusted hazard ratios (HRs) of mortality with 95% confidence intervals (CIs).

RESULTS

During about 12 years (9,396 person-years) follow-up, 329 deaths from all causes were documented, including 102 deaths due to expanded cardiovascular disease (CVD). In the multivariable-adjusted, time-varying Cox proportional hazard model, the adjusted HR values of all-cause mortality were 1.47 (1.02-2.12) for sleep duration > 9 h/day (vs. 7 h/day) and 1.81 (1.26-2.59) for MMSE < 27 (vs. 30). The adjusted HR values of the expanded CVD mortality were 2.91 (1.24-6.83) for MMSE of 29; 2.69 (1.20-6.05) for MMSE of 27-28; and 4.32 (95% CI: 1.92-9.74) for MMSE < 27. The dose-dependent relationship was significant (p < 0.001). The combinations of sleep duration longer than 9 h/day and MMSE < 27 were linked with the highest risks for expanded CVD and all-cause mortality.

CONCLUSIONS

Long sleep duration and low cognitive function were jointly and independently linked with higher risk of mortality in elders residing in community.

The Effects of Anterior Palatoplasty and Functional Expansion Sphincter Pharyngoplasty on Voice Quality in Patients with Obstructive Sleep Apnea

OBJECTIVES

We aimed to examine the effects of anterior palatoplasty (AP) and functional expansion sphincter pharyngoplasty (FESP) on voice quality in patients with OSAS and to compare them with each other.

MERHODS

The study included 380 patients who came to the Otorhinolaryngology Clinic of our hospital with symptoms of snoring and sleep apnea between April 2020 and April 2022 and were referred to the sleep laboratory for polysomnography (PSG).Forty patients who met the study criteria and underwent AP and 26 patients who underwent FESP were included in the study. All surgeries were performed under general anesthesia by the same otolaryngologist within 1 month at the latest after sleep endoscopy. Acoustic voice analysis was performed using the Praat voice analysis program preoperatively and postoperatively at 6 months. F0, jitter, shimmer, and NHR (noise-to-harmonic ratio) were compared between the groups pre and postoperatively.

RESULTS

There were 20 females and 20 males in the AP group, 12 females and 14 males in the FESP group, There was no statistically significant difference in sex distribution between the groups (P = 0.952). The difference between the preop and postop F0, jitter, shimmer, and NHR in both the AP and FESP groups was statistically significant (P < 0.01). After AP and FESP surgeries, F0 values ​​increased, jitter, shimmer and NHR values ​​decreased (P < 0.01).F0, jitter, shimmer, and NHR changes were the greatest in the FESP group.(P < 0.01).

CONCLUSION

Positive changes in F0, jitter, shimmer, and NHR were greatest in the FESP group significantly. FESP surgery affects voice quality more than AP surgery in patients with OSAS.

Sleep duration predicts subsequent long-term mortality in patients with type 2 diabetes: a large single-center cohort study

Background

Sleep duration is associated with mortality. However, prior studies exploring whether sleep duration predicts subsequent long-term mortality in patients with diabetes are limited. This study aims to examine whether metabolic factors affect the associations between baseline sleep duration and subsequent risks of all-cause, expanded, and non-expanded cardiovascular disease (CVD) mortalities among patients with type 2 diabetes (T2D).

Methods

A total of 12,526 T2D patients aged 30 years and older, with a follow-up period ≥ 3 years, were identified from the Diabetes Case Management Program of a medical center in Taiwan. Sleep duration was measured using computerized questionnaires by case managers, and the time frame for this question was 1 month prior to the interview date. Sleep duration in relation to subsequent mortality from all causes, expanded CVD, and non-expanded CVD was examined using Cox proportional hazard models.

Results

Within 10 years of follow-up, 2918 deaths (1328 CVD deaths and 1590 non-CVD deaths) were recorded. A J-shaped association was observed for all-cause, expanded CVD, and non-expanded CVD mortalities, and the lowest risks were observed for patients with 5–7 h of sleep. The significant joint effects included sleep duration of more or less than 7 h with age ≥ 65 years [adjusted HRs: 4.00 (3.49–4.60)], diabetes duration ≥ 5 years [1.60 (1.40–1.84)], age at diabetes diagnosis ≤ 45 years [1.69 (1.38–2.07)], insulin use [1.76 (1.54–2.03)], systolic blood pressure/diastolic blood pressure > 130/85 mmHg [1.24 (1.07–1.43)], triglyceride ≥ 150 mg/dL [1.38 (1.22–1.56)], HbA1c ≥ 7% [1.31 (1.13–1.52)], and body mass index < 27 kg/m² [1.31 (1.17–1.45)] for all-cause mortality.

Conclusion

A J-shaped association was observed between sleep duration and all-cause and expanded CVD mortality, and a sleep duration of 5–7 h had the lowest mortality risk. Sleep duration also showed significant synergistic interactions with diabetes duration but shared an antagonistic interaction with age and obesity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01500-0.

Optimal application of soft-palate webbing flap pharyngoplasty combined with nasal surgery for surgical treatment of primary snoring and obstructive sleep apnea

Background

Excessive collapse of the soft palate and lateral pharyngeal wall narrowing are established causes of loud snoring and sleep apnea in subjects with obstructive sleep apnea (OSA). Therefore, delicate surgical techniques are needed to reshape the soft palate and create sufficient tension in the lateral pharyngeal wall. This study aimed to determine the therapeutic outcome and favorable indications of soft-palate webbing flap pharyngoplasty in subjects with OSA and primary snoring.

Methods

A total of 174 subjects who underwent soft-palate webbing flap pharyngoplasty combined with uvulopalatal flap and septoturbinoplasty from August 2015 to February 2020 were included in this study. Medical records, including pre- and postoperative sleep parameters, were retrospectively reviewed. The primary outcome measure was the degree of improvement in AHI after surgery. Other outcomes were differences in surgical response rates, subjective visual analog score (VAS) for snoring, sleep quality, and complications.

Results

Polysomnographic results showed that apnea–hypopnea index (AHI) scores were significantly reduced from 39.6 ± 6.1 to 22.9 ± 3.6 following soft-palate webbing flap pharyngoplasty in 59 subjects, and overall success and response rates of this technique were analyzed with 71%. We found that the successful outcomes were observed in 50% of mild (n = 12) and 56% of moderate (n = 16) subjects with OSA subjects due to lateral pharyngeal wall collapse. The success rate of soft-palate webbing flap pharyngoplasty was relatively higher in subjects with mild and moderate OSA than those with severe OSA. Additionally, the mean VAS snoring scale was 4.7 and subjects’ primary snoring intensity significantly improved to 2.9 after soft-palate webbing flap pharyngoplasty. Subjective symptoms such as daytime sleepiness and sleep quality also showed improvement. Most complications were found to be minimal and improved by 1 month after the operation.

Conclusion

Our data demonstrate that soft-palate webbing flap pharyngoplasty is an effective treatment for OSA and primary snoring and may be a promising technique to reduce lateral pharyngeal wall collapse.

Sleep apnoea in the elderly: a great challenge for the future

Due in part to overall improvements in health, the population of elderly individuals is increasing rapidly. Similarly, obstructive sleep apnoea (OSA) is both gaining increased recognition and also increasing due to the worldwide obesity epidemic. The overlap of OSA and aging is large, but there is strong plausibility for causation in both directions: OSA is associated with pathological processes that may accelerate aging and aging related processes; aging may cause physical and neurological changes that predispose to obstructive (and central) apnoea. In addition, the common symptoms (e.g. excessive daytime somnolence, defects in memory and cognition), possible physiological consequences of OSA (e.g. accelerated cardiovascular and cerebrovascular atherosclerosis), and changes in metabolic and inflammatory markers overlap with the symptoms and associated conditions seen in aging. There is also the possibility of synergy in the effects of these symptoms and conditions on quality of life, as well as a need to separate treatable consequences of OSA from age-related complaints. Taken together, the above make it essential to review the interaction of OSA and aging, both proven and suspected. The present review examines some aspects of what is known and points to the need for further investigation of the relationships, given the large number of potentially affected subjects.

Sleep in Older Adults and Its Possible Relations With COVID-19

Since the beginning of the COVID-19 pandemic, older adults have been found to be a highly vulnerable group, with a higher prevalence of severe cases and negative outcomes. Research has focused on the reasons why older adults are at greater risk; Sleep-related factors have been suggested as one possible explanation for this. An individual's sleep pattern undergoes significant changes over the course of their life. In older adults a specific sleep profile can be observed, one characterized by advanced sleep timing, a morningness preference, longer sleep-onset latency, shorter overall sleep duration, increased sleep fragmentation, reduced slow-wave sleep and, increased wake time after sleep onset. Additionally, an increased prevalence of sleep disorders can be observed, such as obstructive sleep apnea and insomnia. Previous research has already linked sleep disorders (especially sleep apnea) with COVID-19, but few studies have focused specifically on the older population. We believe that the intrinsic sleep patterns of older adults, and the prevalence of sleep disorders in this population, may be important factors that could explain why they are at a greater risk of negative COVID-19 outcomes. In this review, we discuss the relationship between sleep and COVID-19 among older adults, focusing on three different aspects: (1) Sleep-related issues that might increase the likelihood of getting infected by SARS-COV-2; (2) Sleep disturbances that might increase the predisposition to worse COVID-19 prognosis and outcomes; and (3) COVID-19-related aspects affecting community-dwelling older adults, such as social isolation, quarantine, and home confinement, among others, that might impact sleep.

Obstructive Sleep Apnea-hypopnea Syndrome as a Novel Potential Risk for Aging

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a common sleep disorder, negatively influencing individuals' quality of life and socioeconomic burden. In recent years, OSAHS has been reported in not only constituting an aging-associated disease, but also in accelerating and/or potentiating aging mechanisms. However, the negative impacts of OSAHS on aging are underestimated because of low level of public awareness about this disease and high rates of undiagnosed cases, which are more critical in developing countries or economically disadvantaged regions. Hence, reviewing previously reported observations may assist scholars to better indicate that OSAHS is likely a novel potential risk for aging. Further understanding of the pathophysiological mechanism of OSAHS and its role in procession of aging may markedly highlight the importance of this common sleep disorder.

NAD+ metabolism, stemness, the immune response, and cancer

NAD⁺ was discovered during yeast fermentation, and since its discovery, its important roles in redox metabolism, aging, and longevity, the immune system and DNA repair have been highlighted. A deregulation of the NAD⁺ levels has been associated with metabolic diseases and aging-related diseases, including neurodegeneration, defective immune responses, and cancer. NAD⁺ acts as a cofactor through its interplay with NADH, playing an essential role in many enzymatic reactions of energy metabolism, such as glycolysis, oxidative phosphorylation, fatty acid oxidation, and the TCA cycle. NAD⁺ also plays a role in deacetylation by sirtuins and ADP ribosylation during DNA damage/repair by PARP proteins. Finally, different NAD hydrolase proteins also consume NAD⁺ while converting it into ADP-ribose or its cyclic counterpart. Some of these proteins, such as CD38, seem to be extensively involved in the immune response. Since NAD cannot be taken directly from food, NAD metabolism is essential, and NAMPT is the key enzyme recovering NAD from nicotinamide and generating most of the NAD cellular pools. Because of the complex network of pathways in which NAD⁺ is essential, the important role of NAD⁺ and its key generating enzyme, NAMPT, in cancer is understandable. In the present work, we review the role of NAD⁺ and NAMPT in the ways that they may influence cancer metabolism, the immune system, stemness, aging, and cancer. Finally, we review some ongoing research on therapeutic approaches.

The role of antioxidant vitamins and selenium in patients with obstructive sleep apnea

PURPOSE

Obstructive sleep apnea (OSA) is a disorder characterized by recurrent episodes of obstruction of the upper respiratory tract during sleep often accompanied by oxygen desaturations. Antioxidant defense mechanisms are important to prevent OSA-associated diseases and decrease mortality. We aimed to determine the levels of selenium and vitamins A, C, and E in patients with OSA but without any comorbidities and compare the results with a control group, theorizing that the findings may be helpful to understand the antioxidant mechanisms in the pathogenesis of OSA and associated diseases.

METHODS

We designed a case-control study with 146 subjects. Subjects were categorized into four groups by apnea-hypopnea index (AHI) scores: control (n = 32; AHI < 5), mild OSA (n = 32; 5 ≤ AHI < 15), moderate OSA (n = 34; 15 ≤ AHI < 30), and severe OSA (n = 48; AHI ≥ 30) groups. Serum levels of selenium were measured by atomic absorption spectrometer. Vitamin A, C, and E levels were measured by high-performance liquid chromatography and ultraviolet (HPLC-UV) detector.

RESULTS

After adjusting for age, BMI, and gender, serum selenium and vitamin A levels were found to be higher in patients with OSA compared with controls (ANCOVA, p < 0.008, and p = 0.014 respectively), and levels of these markers increased with the severity of the disease. AHI was positively correlated with selenium (r = 0.289; p < 0.001), and vitamin A levels (r = 0.276; p < 0.001).

CONCLUSION

These results demonstrated that antioxidant response with increased vitamin A, and selenium concentrations, may be important defense mechanisms in patients with OSA patients who do not have other comorbidities. Antioxidant nutrients or supplements may be implemented as a complementary treatment of OSA to support antioxidant defense.

Indications for and Outcomes of Expansion Sphincter Pharyngoplasty to Treat Lateral Pharyngeal Collapse in Patients With Obstructive Sleep Apnea

Importance

The lateral pharyngeal wall is recognized as an important site of upper airway collapse during sleep in patients with obstructive sleep apnea (OSA), and expansion sphincter pharyngoplasty (ESP) may have promising clinical utility in patients with OSA and lateral pharyngeal wall collapse.

Objectives

To evaluate the therapeutic outcomes of ESP in conjunction with other surgical procedures and to investigate indications for ESP in patients with OSA.

Design, Setting, and Participants

Cohort study of 63 patients with OSA diagnosed with lateral pharyngeal collapse under drug-induced sleep endoscopy who underwent ESP combined with tonsillectomy, uvuloplasty, or nasal surgery at Seoul National University Hospital in Seoul, Korea, between March 1, 2015, and December 1, 2016.

Main Outcomes and Measures

The primary outcome measure was the change in the apnea-hypopnea index (AHI) after surgery (AHI represents the number of apnea-hypopnea events per hour). Other outcome measures were differences in the surgical response rates, lowest oxygen saturation, subjective visual analog scale scores for snoring and apnea, and Epworth Sleepiness Scale score.

Results

Fifty of the 63 patients (79%) were male; the mean age was 42.1 (range, 20-54) years, and the mean body mass index (calculated as weight in kilograms divided by height in meters squared) was 27.6 (range, 19.0-32.1). Expansion sphincter pharyngoplasty was performed in patients with OSA with an AHI greater than 15 events per hour, more than 75% retropalatal circumferential narrowing when awake, and narrowed oropharynx due to bulky soft tissue around the lateral pharyngeal wall. In 42 of the 63 patients (67%), ESP was objectively successful in correcting lateral pharyngeal collapse; there was a significant reduction in mean AHI from 35.5 to 17.3 (mean difference, 18.1; 95% CI, 16.3-20.0) and improvement of the lowest mean (SD) oxygen saturation measurement from 78.2% (21.3%) to 86.4% (10.6%) (mean difference, 8.60%; 95% CI, 6.60%-10.60%) 6 months after the operation. The rate of postoperative complications, including pain and bleeding, was minimal after ESP, and a few patients reported an abnormal sensation around the soft palate and swallowing difficulty after ESP.

Conclusions and Relevance

Expansion sphincter pharyngoplasty appears to be a promising surgical technique to reduce lateral pharyngeal collapse in patients with moderate or severe OSA. Clinical data suggest that both severe palatal circumferential narrowing and bulky lateral pharyngeal tissue are favorable surgical indications for ESP in patients with OSA.

Treatment with CPAP in Elderly Patients with Obstructive Sleep Apnoea

The population pyramid is changing as a result of the ever-increasing life expectancy, which makes it crucial to acquire an in-depth understanding of the diseases that most often affect the elderly. Obstructive sleep apnoea (OSA) affects 15%-20% of the population aged over 65 years. Despite this prevalence, there have been very few specific studies on the management of OSA in this age group, even though over 60% of the patients aged over 65-70 years who attend sleep units with suspicion of OSA receive treatment with continuous positive airway pressure (CPAP), on the basis of an extrapolation of the positive results achieved by CPAP in clinical trials involving middle-aged males. However, the latter's form of presentation, evolution and, probably, prognosis comparing with OSA are not the same as those of elderly patients. Recent clinical trials performed on an exclusive series of elderly patients have shed light on the possible role of CPAP treatment in elderly patients with OSA, but there are still many questions that need to be answered. The physiological increase in the number of sleep-related disorders with the passing of years, and the lack of validated diagnostic and therapeutic tools for this age group are probably the greatest obstacles to define, diagnose and treat OSA in the elderly.

The clinical efficacy of relocation pharyngoplasty to improve retropalatal circumferential narrowing in obstructive sleep apnea patients

Lateral pharyngeal wall appears to be a critical culprit of obstructive sleep apnea (OSA) subjects and relocation pharyngoplasty has been expected to be a promising surgical option to correct retropalatal circumferential narrowing in OSA patients. The purpose of our study is to evaluate the therapeutic outcomes of relocation pharyngoplasty and its clinical effectiveness in OSA patients with retropalatal circumferential narrowing. We performed relocation pharyngoplasty combined with nasal surgery in 133 OSA patients with the following characteristics: apnea-hypopnea index (AHI) over 10, retropalatal circumferential narrowing greater than grade I when awake, and redundant soft tissue around the lateral pharyngeal wall. The analysis of surgical success rate was performed with the data of 68 subjects who underwent pre and postoperative polysomnography. The objective success rate of relocation pharyngoplasty was 52.9%, and significant reduction of mean AHI with improvement of lowest SpO2 was seen in 69% of patients 3 months after the surgery. The median AHI was decreased from preoperative 37.3 to postoperative 21.4. Median lowest SpO2 changed from 78.4 to 84.1%. Total sleep time, daytime sleepiness, and visual analogue scale for snoring showed improvement as well. Postoperative complications including pain or bleeding were minimal in 133 subjects and a few patients complained of subtle taste loss. Our data demonstrate that relocation pharyngoplasty can be a favorable surgical option fighting against retropalatal circumferential narrowing.

Robot-assisted Tongue Base Resection ensures favorable therapeutic outcome to Obstructive Sleep Apnea patients with Lingual tonsil hypertrophy

Tongue base (TB) narrowing is recognized as a significant site of upper airway collapse during sleep in obstructive sleep apnea (OSA) patients and robot technology is expected to have promising clinical utility in OSA patients with TB narrowing. The purpose of our study is to demonstrate the better therapeutic conditions and favorable indications of robot-assisted TB resection (TBR) in OSA. We performed robot-assisted TBR combined with nasal and palatal surgery in 16 OSA patients with any of the following characteristics: severe TB narrowing (over grade II) and moderate or severe OSA. The preoperative median AHI was 48.8/hr and the median lowest SaO₂ was 82.0%. The median AHI decreased to 18.7/hr and ten patients (62.5%) were included in the responder group following robot-assisted TBR combined with nasal and palatal surgery. The lowest SaO₂ improved to 90.5% and the posterior airway space (PAS) was significantly increased following robot-assisted TBR. Cephalometric results showed that wider PAS were observed in responders compared to non-responders prior to robot-assisted TBR. Interestingly, there was greater improvement in the objective parameters including PAS in the OSA patients with lingual tonsilar hypertrophy than they were in those without and all patients with lingual tonsillar hypertrophy (n = 6) responded to robot-assisted TBR. Robot-assisted TBR exhibited minimal morbidity and postoperative complications in OSA patients. Robot-assisted TBR can be considered a promising and innovative surgical option to reduce TB volume and improve sleep parameters in OSA patients with TB narrowing. OSA patient with TB narrowing due to lingual tonsil hypertrophy shows greater therapeutic outcome and lingual tonsil hypertrophy appears to be most favorable surgical indications of robot-assisted TBR.

Influencing factors on CPAP adherence and anatomic characteristics of upper airway in OSA subjects

Although continuous positive airway pressure (CPAP) is the most effective treatment modality, poor adherence still remains a problem for obstructive sleep apnea (OSA) treatment and there is little evidence regarding how this might be improved. This study aims to analyze the anatomic and clinical factors of OSA subjects who failed to comply with CPAP therapy.The medical records of 47 OSA subjects who received CPAP therapy as a first-line treatment modality were retrospectively reviewed. The medical records were reviewed for demographic and polysomnographic data and anatomic findings of the nasal cavity and oropharynx.24 patients who adhered to CPAP therapy and 23 patients who were nonadherent were enrolled in the study. There were no statistically significant differences in sleep parameters between CPAP-adherent patients and CPAP nonadherent subjects. Mean body mass index of CPAP nonadherent group was significantly higher than CPAP adherent group. Higher grades of septal deviation and hypertrophic change of the inferior turbinate were observed more in the CPAP nonadherent group. In addition, CPAP nonadherent subjects showed considerably bigger tonsils and higher grade palatal position comparing with the CPAP adherent subjects. Subjective discomfort including inconvenience, mouth dryness, and chest discomfort were the main problems for OSA subjects who did not comply with CPAP therapy.Excessive upper airway blockage in the nasal cavity and oropharynx was predominant in CPAP nonadherent subjects, which might cause the reported subjective discomfort that reduces CPAP compliance. Therefore, resolution of these issues is needed to enhance CPAP compliance for control of OSA.

The structural changes of upper airway and newly developed sleep breathing disorders after surgical treatment in class III malocclusion subjects

Bimaxillary surgery is the traditional treatment of choice for correcting class III malocclusion which is reported to cause an alteration of oropharyngeal structures and upper airway narrowing that might be a predisposing factor for obstructive sleep apnea (OSA). This study aimed to analyze sleep parameters in class III malocclusion subjects and ascertain the prevalence of snoring or OSA following bimaxillary surgery.A total of 22 patients with Le Fort I osteotomy and mandibular setback for class III malocclusion were prospectively enrolled. All patients received endoscopic examination, cephalometry, 3-dimensional computed tomography (3D-CT), and sleep study twice at 1 month before and 3 months after surgery.The patient population consisted of 5 males and 17 females with a mean body mass index of 22.5 kg/m and mean age of 22.1 years. No patients complained of sleep-related symptoms, and the results of sleep study showed normal values before surgery. Three patients (13%) were newly diagnosed with mild or moderate OSA and 6 patients (27%) showed increased loudness of snoring (over 40 dB) after bimaxillary surgery. According to cephalometric analysis and 3D-CT results, the retropalatal and retroglossal areas were significantly narrowed in class III malocclusion patients, showing snoring and sleep apnea after surgery. In addition, the total volume of the upper airway was considerably reduced following surgery in the same patients.Postoperative narrowing of the upper airway and a reduction of total upper airway volume can be induced, and causes snoring and OSA in class III malocclusion subjects following bimaxillary surgery.

Therapeutic outcomes of mandibular advancement devices as an initial treatment modality for obstructive sleep apnea

Although continuous positive airway pressure (CPAP) is a highly efficacious treatment for obstructive sleep apnea (OSA), there is a need for alternative treatment options, such as sleep surgeries and mandibular advancement devices (MADs), to overcome the limitations of CPAP.This study aimed to analyze the therapeutic outcomes of OSA subjects who were treated with a MAD, and to estimate the clinical impact of MAD as a first-line treatment for OSA.Forty-seven patients diagnosed with OSA received an adjustable MAD as an initial treatment. Drug-induced sleep endoscopic findings and sleep parameters (both pre-MAD and post-MAD treatment), such as apnea index, oxygen saturation, and degree of daytime sleepiness, were assessed retrospectively.The MAD treatment resulted in a significant reduction in apnea-hypopnea index, and also a significant elevation in lowest oxygen saturation. Satisfactory results of MAD treatment as a first treatment modality were observed in 27 patients, and a successful outcome was reached in approximately 72% of patients. The OSA patients who had lower body mass index and upper airway narrowing at the level of palate and tongue base showed relatively higher rates of a satisfactory outcome even in cases of moderate or severe OSA.These results suggest that the use of a MAD may be an alternative treatment option in OSA patients with retropalatal and retroglossal area narrowing regardless of disease severity. Additionally, MADs can be recommended as an initial treatment modality, and the effectiveness of MADs in achieving success may not be inferior to CPAP.

Oxidative Stress-induced Telomere Length Shortening of Circulating Leukocyte in Patients with Obstructive Sleep Apnea

The main mechanism of pathogenesis which causes systemic complications in obstructive sleep apnea (OSA) patients is believed to be intermittent hypoxia-induced intermediary effect and it depends on the burden of oxidative stress during sleep. We aimed to search the predictive markers which reflect the burden of systemic oxidative stress in patients with OSA and whether excessive telomere length shortening is a characteristic feature that can assess oxidative stress levels. We used quantitative PCR to measure telomere length using peripheral blood genomic DNA. Telomere lengths were compared in an age- and body mass index (BMI)-dependent manner in 34 healthy volunteers and 43 OSA subjects. We also performed reactive oxygen species assay to measure the concentration of hydrogen peroxide in the peripheral blood of healthy volunteers and OSA subjects. We found that the serum concentration of hydrogen peroxide was considerably higher in OSA patients, and that this was closely related with the severity of OSA. Significantly shortened telomere length was observed in the circulating leukocytes of the peripheral blood of OSA patients, and telomere length shortening was aggravated more acutely in an age- and BMI-dependent manner. An inverse correlation was observed between the concentration of hydrogen peroxide and the telomere length of OSA patients and excessive telomere length shortening was also linked to severity of OSA. The results provided evidence that telomere length shortening or excessive cellular aging might be distinctive in circulating leukocyte of OSA patients and may be an predictive biomarker for reflect the burden of oxidative stress in the peripheral blood of OSA patients.

Can mitochondrial dysfunction be a predictive factor for oxidative stress in patients with obstructive sleep apnea?

Mitochondrial dysfunction reflects a lifelong cumulative burden of cellular damage, and a decrease in mitochondrial DNA (mtDNA) copy number is associated with oxidative stress and chronic inflammation. The goal of this study was to assess whether mitochondrial dysfunction and a decrease in mtDNA copy number are common features of patients with obstructive sleep apnea syndrome (OSA). We compared mtDNA copy number between 20 healthy volunteers and 20 patients with OSA and investigated whether a significant attenuation of mtDNA copy number was observed in genomic DNA isolated from whole blood of OSA patients. Our observations lead to the hypothesis that mtDNA copy number is lower in whole blood DNA of OSA subjects and might be related to OSA severity, reflecting excessive oxidative stress in patients with OSA.

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.

Endothelial function is well preserved in obese patients with mild obstructive sleep apnea

PURPOSE

Endothelial dysfunction is one of the early markers of cardiovascular complications in obstructive sleep apnea (OSA). The aim of our study was to evaluate whether overweight patients with mild OSA displayed endothelial dysfunction, and to assess the effect of 1-year lifestyle intervention with an early very low calorie diet in endothelial function.

METHODS

At baseline, the study population consisted of 83 overweight patients with mild OSA and 46 weight-matched non-OSA subjects. OSA patients were further randomized into a 1-year supervised lifestyle intervention group or control group which received routine lifestyle counselling. Endothelial function measured by brachial artery flow-mediated dilatation (FMD), apnea-hypopnea index (AHI), body mass index (BMI), and metabolic parameters were assessed at baseline and 12 months.

RESULTS

No correlations between endothelial function and mild OSA were detected. However, patients with impaired endothelial function had lower mean saturation and impaired endothelial function correlated significantly with glucose intolerance and dyslipidemia. After the lifestyle intervention and successful weight reduction, AHI, BMI, serum triglycerides and insulin improved significantly; however, no improvement in FMD was detected.

CONCLUSIONS

Mild OSA was not observed to be associated with endothelial dysfunction. Although in mild OSA endothelial function is still preserved, lifestyle intervention with weight reduction did achieve an improvement in other obesity-related risk factors for cardiovascular diseases, thus highlighting the importance of early intervention.

Oxidative stress mediated arterial dysfunction in patients with obstructive sleep apnoea and the effect of continuous positive airway pressure treatment

Background

Several studies suggest an increase of oxidative stress and a reduction of endothelial function in obstructive sleep apnoea syndrome (OSAS). We assessed the association between OSAS, endothelial dysfunction and oxidative stress. Further aim was to evaluate the effect of nasal continuous positive airway pressure (nCPAP) on oxidative stress and arterial dysfunction.

Methods

We studied 138 consecutive patients with heavy snoring and possible OSAS. Patients underwent unattended overnight home polysomnography. Ten patients with severe OSAS were revaluated after 6 months of nCPAP therapy. To assess oxidative stress in vivo, we measured urinary 8-iso-PGF2α and serum levels of soluble NOX2-derived peptide (sNOX2-dp). Serum levels of nitrite/nitrate (NOx) were also determined. Flow-mediated brachial artery dilation (FMD) was measured to asses endothelial function.

Results

Patients with severe OSAS had higher urinary 8-iso-PGF2α (p<0.001) and serum NOX2 and lower NOx. A negative association was observed between FMD and OSA severity. Apnea/hypopnea index was significantly correlated with the indices of central obesity and with urinary 8-isoprostanes (r=0.298, p<0.001). The metabolic syndrome (t=-4.63, p<0.001) and urinary 8-isoprostanes (t=-2.02, p<0.05) were the only independent predictors of FMD. After 6-months nCPAP treatment, a significant decrease of serum NOX2, (p<0.005) and urinary 8-iso-PGF2α (p<0.01) was observed, while serum NOx showed only a minor increase. A statistically significant increase of FMD was observed (from 3.6% to 7.0%).

Conclusions

The results of our study indicate that patients with OSAS and cardiometabolic comorbidities have increased oxidative stress and arterial dysfunction that are partially reversed by nCPAP treatment.

Potential role of adult stem cells in obstructive sleep apnea

Adult stem cells are undifferentiated cells that can be mobilized from the bone marrow or other organs, home into injured tissues, and differentiate into different cell phenotypes to serve in a repairing capacity. Furthermore, these cells can respond to inflammation and oxidative stress by exhibiting immunomodulatory properties. The protective and reparative roles of mesenchymal stem cells (MSCs), very small embryonic-like stem cells (VSELs), and endothelial progenitor cells (EPCs) have primarily been examined and characterized in auto-immune and cardiovascular diseases. Obstructive sleep apnea (OSA) is a very prevalent disease (4-5% of adult population and 2-3% of children) characterized by an abnormal increase in upper airway collapsibility. Recurrent airway obstructions elicit arterial oxygen desaturations, increased inspiratory efforts, and sleep fragmentation, which have been associated with important long-term neurocognitive, metabolic, and cardiovascular consequences. Since inflammation, oxidative stress and endothelial dysfunction are key factors in the development of the morbid consequences of OSA, bone marrow-derived stem cells could be important modulators of the morbid phenotype by affording a protective role. This mini-review is focused on the recent data available on EPCs, VSELs, and MSCs in both animal models and patients with OSA.

The interaction of obstructive sleep apnea and obesity on the inflammatory markers C-reactive protein and interleukin-6: the Icelandic Sleep Apnea Cohort

STUDY OBJECTIVES

To assess the relative roles and interaction of obstructive sleep apnea (OSA) severity and obesity on interleukin-6 (IL-6) and C-reactive protein (CRP) levels.

DESIGN

Cross-sectional cohort.

SETTING

The Icelandic Sleep Apnea Cohort.

PARTICIPANTS

454 untreated OSA patients (380 males and 74 females), mean ± standard deviation age 54.4 ± 10.6 yr.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Participants underwent a sleep study, abdominal magnetic resonance imaging to measure total abdominal and visceral fat volume, and had fasting morning IL-6 and CRP levels measured in serum. A significantly higher correlation was found for BMI than visceral fat volume with CRP and IL-6 levels. Oxygen desaturation index, hypoxia time, and minimum oxygen saturation (SaO₂) significantly correlated with IL-6 and CRP levels, but apnea-hypopnea index did not. When stratified by body mass index (BMI) category, OSA severity was associated with IL-6 levels in obese participants only (BMI > 30 kg/m²). A multiple linear regression model with interaction terms showed an independent association of OSA severity with IL-6 levels and an interaction between OSA severity and BMI, i.e., degree of obesity altered the relationship between OSA and IL-6 levels. An independent association of OSA severity with CRP levels was found for minimum SaO₂ only. A similar interaction of OSA severity and BMI on CRP levels was found for males and postmenopausal women.

CONCLUSIONS

OSA severity is an independent predictor of levels of IL-6 and CRP but interacts with obesity such that this association is found only in obese patients.

Idiopathic deep venous thrombosis and arterial endothelial dysfunction in the elderly

Arterial and venous thrombosis have always been regarded as different pathologies and epidemiological studies have examined the association between venous thrombosis and indicators of atherosclerosis and/or arterial thromboembolic events. We measured the flow-mediated dilation (FMD), a well-known marker of arterial endothelial dysfunction, in young-middle-aged and old-aged patients with and without unprovoked deep venous thrombosis (DVT). The aim of this study was to investigate whether DVT was a significant predictor for impaired FMD, considering all the patients and young-middle-aged (age < 65 years) and old-aged (age ≥ 65 years) patients separately. FMD was measured in the brachial artery on a population of 120 subjects with the same atherosclerosis risk factors, 68 male and 52 female, 70 young-middle-aged subjects (mean age ± SD 49.5 ± 10.5 years) and 50 old-aged subjects (76.2 ± 7.7 years). Patients with DVT showed a significant decrease of FMD compared to patients without DVT (6.8 ± 5.5% vs. 10.9 ± 3.5%, p < 0.001). Moreover, old-aged patients showed a significant decrease of FMD compared to the young-middle-aged subjects (7.4 ± 4.1% vs. 9.8 ± 5.3%, p = 0.005). In the whole study population, DVT was strongly associated with FMD (risk factors adjusted β = -4.14, p < 0.001). A significant interaction between age and the presence of DVT on predicting FMD was found (p = 0.003) suggesting a differential behavior of DVT as predictor of FMD. In young-middle-aged group, multivariate model confirmed that DVT was the most significant predictor of continuous FMD (β = -6.06, p < 0.001). On the contrary, DVT was no more a predictor of FMD in the old age group (β = -0.73, p = 0.556). Furthermore, old-aged patients without DVT showed a statistically significant decrease of FMD compared to the young-middle-aged subjects without DVT (8.2 ± 2.1% vs. 12.6 ± 2.7%, p<0.001) and old-aged patients with DVT showed a not statistically significant decrease of the FMD compared to the young-middle-aged patients with DVT (6.7 ± 5.3% vs. 6.8 ± 5.7%, p = 0.932). In conclusion, young-middle-aged patients with spontaneous DVT show an impaired FMD, whereas this impairment in old-aged subjects is evident independently from the presence or absence of DVT. Aging per se may be associated with physiologic abnormalities in the systemic arteries and with endothelial dysfunction.

Oxidative stress in patients with obstructive sleep apnea syndrome

PURPOSE

We aimed to investigate whether systemic oxidative stress is increased in patients with obstructive sleep apnea syndrome (OSAS).

METHODS

A total of 18 patients with severe OSAS and 13 controls were included in the study. Inclusion criteria for OSAS patients were: snoring and apnea-hypopnea index (AHI) of >30 in full polysomnography, no previous treatment for OSAS, non-smoking status, and a medical history of being free of comorbidities known to increase oxidative stress. Controls were recruited among subjects assessed for snoring in the Sleep Laboratory Department if they had AHI<5. At baseline, patients were evaluated by the Epworth Sleepiness Scale and underwent spirometry, echocardiography, and full polysomnographic study. Blood samples were collected for evaluation of oxidative stress biomarkers [protein carbonyls, reduced (GSH) and oxidized (GSSG) glutathione, 8-isoprostane, thiobarbituric acid-reactive substances (TBARS), catalase activity, Cu-Zn superoxide dysmutase (SOD), total antioxidant capacity (TAC)] before and on the morning following polysomnography.

RESULTS

The overnight (morning-night) change (%) of GSH/GSSG ratio and GSH was significantly different between OSAS and controls (p = 0.03 and p = 0.048, respectively). Plasma protein carbonyls, erythrocyte catalase activity, 8-isoprostane, SOD, TBARS, and TAC plasma values were not different between OSAS and controls (p > 0.05). No significant correlation was found between changes in the levels of biomarkers and AHI, arousal, or desaturation index.

CONCLUSION

The present prospective investigation in a population free of comorbidities or factors which may increase systemic oxidative stress provides evidence that obstructive sleep apnea per se might be associated with increased oxidative burden possibly via GSH/GSSG pathway.

Continuous positive airway pressure therapy improves vascular dysfunction and decreases oxidative stress in patients with the metabolic syndrome and obstructive sleep apnea syndrome

BACKGROUND

Patients with obstructive sleep apnea syndrome (OSAS) are always exposed to intermittent hypoxia and reoxygenation. The metabolic syndrome (MetS) and OSAS are also known to accelerate atherosclerosis, diabetes, and dyslipidemia. Therefore, nasal continuous positive airway pressure (CPAP) therapy may have beneficial effects in patients with the MetS and OSAS.

HYPOTHESIS

This study in patients with the MetS and OSAS tested the validity of the hypothesis that chronic CPAP therapy improves factors involved in atherosclerosis, including impaired endothelial function.

METHODS

Thirty-two patients (19 males and 13 females, mean age 54 ± 9 y) diagnosed with the MetS and OSAS were enrolled in the study and received CPAP therapy for 3 months. Vascular function was investigated by measuring forearm blood flow (FBF) responses to reactive hyperemia (RH) using venous occlusion strain-gauge plethysmography. Biochemical markers were also measured before and after this procedure.

RESULTS

Basal apnea-hypopnea index was statistically correlated with FBF response to RH. The FBF response to RH was increased significantly after 3 months of CPAP therapy. A significant increase in plasma nitric oxide levels and a decrease in the levels of asymmetrical dimethylarginine, thiobarbituric acid reactive substance, soluble Fas ligand, and soluble CD40 ligand were detected after CPAP therapy. The plasma concentrations of tumor necrosis factor-α, interleukin (IL)-6, and IL-8 also decreased significantly with CPAP therapy, whereas IL-1β levels remained unchanged.

CONCLUSIONS

Continuous positive airway pressure therapy has beneficial effects on vascular function and inflammatory and oxidative stress in patients with the MetS and OSAS.

Reversibility of the endothelial dysfunction after CPAP therapy in OSAS patients

BACKGROUND

The obstructive sleep apnoea syndrome (OSAS) is a common airways disease which often involves cardiovascular structures, causing vessel inflammation as well as hypoxia, induced by difficulties in the passage of air through the upper airways. Aim of our research is to evaluate the effects of Continuous Positive Airway Pressure (CPAP) on the syndrome itself and the patients cardiovascular risk profile, practically adopting Flow-Mediated Vasodilation (FMD) technique to evaluate endothelial function.

METHODS AND RESULTS

We enrolled 63 patients (49 males and 14 female, mean age: 54 ± 10 years) subdivided into four groups: high cardiovascular risk factors, no CPAP therapy, CPAP therapy started less- and more than 3 months before. The patients underwent FMD of the brachial artery using a high resolution ultrasonograph connected to an image analysis system. The maximum recovery value was calculated as the ratio (maximum-baseline) of the change in diameter over the baseline value. Data obtained from this study demonstrate the significant reversibility of FMD in patients treated for more than 3 months with CPAP therapy (Group 4).

CONCLUSIONS

Our study shows the importance of administering CPAP therapy for more than 3 months in patients suffering from OSAS to improve EF to a level equal to high cardiovascular risk subjects probably due to a recovery from the systemic hypoxia. Besides, our work points out the importance of FMD as a "clinical" tool able to point out any improvement or regression after therapies.

Patients with obstructive sleep apnea exhibit impaired endothelial function after myocardial infarction

BACKGROUND

Impaired brachial flow-mediated dilation (FMD) is associated with risk for subsequent cardiovascular events in patients after myocardial infarction (MI). These patients often have obstructive sleep apnea (OSA). We tested the hypothesis that patients with OSA post MI will exhibit more severe impairment in FMD.

METHODS

We studied 64 patients with MI admitted to our hospital. OSA was determined using polysomnography. FMD was measured using high-resolution ultrasonography, with researchers blind to the OSA diagnosis.

RESULTS

The mean age was 60 ± 11 years, and the mean BMI was 29 (26, 32 kg/m(2)), 84% of patients were men, 39% had moderate to severe OSA (apnea-hypopnea index [AHI] > 15), and 31% of the patients had mild OSA (5 ≤ AHI < 15). FMD was severely impaired in patients with moderate to severe OSA (0.8% ± 0.7%) as compared with patients without OSA (4.7% ± 0.8%, P = .001) and with mild OSA (3.9% ± 0.8%, P = .015). Linear regression showed that FMD was associated with log nocturnal nadir oxygen saturation (minSaO(2)) (β = 31.17, P = .0001), age (β = -0.11, P = .006). MinSaO(2) was an independent predictor of FMD after adjustment for possible confounders (β = 26.15, P = .001).

CONCLUSIONS

FMD is severely impaired in patients with moderate to severe OSA post MI, which may be partially related to nocturnal hypoxemia. Patients with OSA may, therefore, be at higher risk for subsequent cardiovascular events after an MI. Identifying and treating OSA may have important implications in the long-term prognosis of patients post MI. Further studies are necessary to determine if the presence of OSA would affect the long-term occurrence of cardiovascular events after an MI.

The relation between Lp-PLA2 levels with periodic limb movements

OBJECTIVE

Lipoprotein-associated phospholipase A2 (Lp-PLA2), a novel marker of vulnerable plaque to prone rupture, is a predictor of both cardiovascular event and cerebrovascular event, and highly sensitive-C-reactive protein (hs-CRP) is an acute-phase response protein implicated in a broad range of cardiovascular diseases. We aimed to examine the association between periodic limb movements in sleep (PLMs) with circulating Lp-PLA2 and hs-CRP levels in patients with PLMs.

METHODS

Seventy patients with newly diagnosed PLM with polysomnography were enrolled this study. Patients were divided into two groups according to PLM index (normal PLM index, <15; elevated PLM index, ≥15). Lp-PLA2 and hs-CRP concentrations were measured in serum samples by turbidimetric and nephelometric methods, respectively. The concentrations of these parameters were compared between two groups and correlation analysis was performed between PLMs and Lp-PLA2 and hs-CRP levels.

RESULTS

Lp-PLA2 levels and hs-CRP were significantly increased in elevated PLM index group compared with the control group (206.8 ± 78.1 vs 157.8 ± 56.7, p = 0.003, and 4.2 ± 3.5 vs 2.4 ± 2.1, p = 0.02, respectively). PLM index was positively correlated with Lp-PLA2 levels (r = 0.40, p = 0.001) and hs-CRP (r = 0.24, p = 0.05). In the linear regression model, Lp-PLA2 was an independent predictor of PLM index (R(2) = 0.36, p = 0.005).

CONCLUSION

This study demonstrated an independent linear relation between PLM index and Lp-PLA2. In addition, it was seen increased Lp-PLA2 and hs-CRP levels in patients with elevated PLM index. Based on these results, we can suggest that risk of vascular events may be increased in patients with PLMs and with increased PLM index.

Obstructive sleep apnea and aging effects on macrovascular and microcirculatory function

STUDY OBJECTIVES

Many patients with obstructive sleep apnea (OSA) are obese, and whether obesity itself explains the increased prevalence of cardiovascular disease in OSA is unknown. We hypothesize that OSA, independent of obesity, contributes to abnormal vascular function.

DESIGN

Physiology study.

SETTING

Academic medical centers.

PATIENTS

Obese subjects, free of known comorbidities, were enrolled.

MEASUREMENTS AND RESULTS

Vascular function was assessed with brachial artery ultrasound for flow-mediated dilation (FMD) and in skin microcirculation by laser Doppler flowmetry. Arterial stiffness was measured by arterial tonometry. Seventy-two subjects (43/72 women, 38/72 with OSA) were studied. FMD was impaired in patients with OSA, compared with control subjects (5.7% +/- 3.8% vs 8.3% +/- 4.1%, P = 0.005). In step-forward regression analysis inclusive of age, sex, and body mass index, age (P = 0.013) was a significant independent predictor of FMD. In a subgroup of subjects younger than 50 years of age (n = 59), however, OSA was the only independent predictor of FMD (P = 0.04), adjusted for known covariates. OSA did not significantly influence vascular function in the skin microcirculation. The augmentation index, a measure of arterial stiffness, was similar between the OSA and control groups (16.2% +/- 11.4% vs 20.4% +/- 10.1%, respectively, P = 0.10). In step-forward regression analysis of younger men (< or = 50 years old, 23 subjects), OSA independently predicted the augmentation index in men only (P = 0.001).

CONCLUSIONS

In obesity, both OSA and aging impair endothelial function and increase arterial stiffness. The influence of OSA on vascular function is most pronounced in young subjects. OSA, therefore, may be associated with functional impairment ("a premature aging effect") on the endothelium and on arterial stiffness (in men), although skin microcirculatory function appears preserved.

The effect of smoking on arterial stiffness

A systematic literature review was conducted using PubMed, Embase and the Cochrane Library to determine the effect of acute, chronic and passive smoking on arterial stiffness and to determine whether these effects are reversible after smoking cessation. A total of 39 relevant studies were identified and included. Acute smoking was found to cause an acute increase in arterial stiffness. Similarly, passive smoking increased arterial stiffness acutely and chronically. The majority of studies identified chronic smoking as a risk factor for increasing arterial stiffness. However, some studies found no statistical difference in arterial stiffness between nonsmokers and long-term smokers, although chronic smoking seems to sensitize the arterial response to acute smoking. In addition, whether arterial stiffness is reversed after smoking cessation and the timeline in which this may occur could not be determined from the identified literature. The effect of smoking discontinuation on arterial stiffness remains to be established by prospective smoking cessation trials.

Avaliação da dilatação máxima da artéria braquial em gestantes e não gestantes, fumantes e não fumantes

OBJETIVO: Avaliar, por meio da dilatação mediada por fluxo da artéria braquial, em que tempo ocorre a máxima dilatação da artéria braquial e se existe diferença nesta avaliação ao comparar mulheres gestantes e não gestantes, fumantes e não fumantes. MATERIAIS E MÉTODOS: Estudo transversal, no qual o diâmetro da artéria braquial foi avaliado em quatro tempos após estímulo pressórico (30, 60, 90 e 120 segundos) em quatro grupos de mulheres entre 20 e 30 anos de idade assim distribuídos: mulheres gestantes entre 24 e 28 semanas de idade gestacional não fumantes (n = 47) e fumantes (n = 33), e mulheres não gestantes não fumantes (n = 34) e fumantes (n = 19). RESULTADOS: A avaliação da dilatação da artéria braquial nos diferentes tempos após o estímulo pressórico foi máxima para todos os grupos no tempo "60 segundos" após a desinsuflação (p < 0,01). A dilatação mediada por fluxo da artéria braquial foi maior entre as mulheres gestantes não fumantes em comparação às fumantes (p = 0,03), assim como no grupo de mulheres não gestantes não fumantes em comparação às fumantes (p = 0,03). CONCLUSÃO: O hábito de fumar não interferiu no tempo em que ocorre a máxima dilatação da artéria braquial.

Diurnal variability of C-reactive protein in obstructive sleep apnea

OBJECTIVE

The objective of this study is to examine the diurnal variability of C-reactive protein (CRP) in obstructive sleep apnea (OSA).

METHODS AND MEASUREMENTS

Participants included 44 women and men with untreated OSA (mean apnea/hypopnea index = 37.5, SD +/- 28) and 23 healthy adults with no OSA. Sleep was monitored with polysomnography in the University of California San Diego General Clinical Research Center. Over a 24-h period, blood was collected every 2 h, and CRP levels were determined.

RESULTS

Adjusting for age, gender, and body mass index, a significant group by time interaction showed that patients with OSA had higher CRP levels during the daytime (8:00 a.m.-8:00 p.m.) versus the nighttime (10:00 p.m. until 6:00 p.m.; p < 0.001). Non-apneics showed no significant change in CRP levels during the 24 h.

CONCLUSIONS

The findings indicate that sleep apnea patients have disproportionately elevated CRP levels in the day versus the nighttime, possibly as a result of carryover effects of nighttime arousal into the daytime.