Cerebral structural changes in severe obstructive sleep apnea

Obstructive sleep apnea is associated with abnormalities in neuropsychologic function, and defects in respiratory control may contribute to pathogenesis. Abnormalities may be reflected in structural brain changes. Twenty-seven male untreated patients with severe sleep apnea without comorbidities, and 24 age-matched control subjects, had T1-weighted brain imaging in a high-resolution magnetic resonance scanner. Twenty-three patients with sleep apnea had repeat imaging after 6 months of continuous positive airways pressure treatment. No areas of gray matter volume change were found in patients using an optimized voxel-based morphometry technique, at p < 0.05 adjusted for multiple comparisons (despite the method being sensitive to changes in gray matter fraction of 0.17 or less in all voxels). Furthermore, no differences were seen in bilateral hippocampal, temporal lobe, or whole brain volumes, assessed by manual tracing of anatomical borders. No longitudinal changes were seen in gray matter density or regional volumes after treatment, but whole brain volume decreased slightly. We have found no gray matter volume deficits nor focal structural changes in severe obstructive sleep apnea. Whole brain volume decreases without focal changes after 6 months of continuous positive airways pressure treatment.     

Clinical features of obstructive sleep apnea hypoventilation syndrome in otherwise healthy children.

Obstructive sleep apnea hypoventilation syndrome (OSAHS) is an important public health problem. However, major gaps exist in our knowledge about the clinical features of this disorder in the pediatric age group. The purpose of this study was to examine clinical features of OSAHS diagnosed by polysomnography in otherwise healthy children. In this cross-sectional study, 326 children without underlying medical conditions (5.8+/-3.0 years, range 1-12 years; 56% male) were recruited from patients referred by primary care and otorhinolaryngology physicians for evaluation of snoring and difficulty breathing. Ethnic group distribution was African-American (38%), Caucasian (30%), and Hispanic (31%). Complaints of daytime tiredness or sleepiness were reported in 29% of the children. All children underwent overnight polysomnography (N = 330 studies). OSAHS was diagnosed in 59% of the children, based on polysomnographic criteria. The remaining children had either primary snoring (25%); no snoring (10%), or upper airway resistance syndrome (6%). Neither male gender nor obesity increased the likelihood for the diagnosis of OSAHS. However, the incidence of obesity in the study population (28%) was more than twice that of the general pediatric population. African-American children had a greater likelihood for OSAHS diagnosis compared to Hispanic or Caucasian children. Daytime complaints of sleepiness or tiredness were not more common in children diagnosed with OSAHS than in the children without OSAHS. As expected, tonsillar hypertrophy increased the likelihood of OSAHS diagnosis. In summary, many of the clinical features of childhood OSAHS are in marked contrast to those in adults.     

Severity of obstructive sleep apnea is associated with elevated plasma fibrinogen in otherwise healthy patients

Purpose

Obstructive sleep apnea (OSA) has been implicated in both cardiovascular and cerebrovascular diseases. Systemic inflammation and coagulation may be related to cardiovascular pathophysiology in patients with OSA. Fibrinogen is a major coagulation protein associated with inflammation, and long-term elevated plasma fibrinogen is associated with an increased risk of major cardiovascular diseases. We assessed whether severity of OSA is associated with levels of fibrinogen in newly diagnosed, untreated, and otherwise healthy OSA patients.

Methods

We studied 36 men with OSA and 18 male control subjects (apnea–hypopnea index [AHI] <5 events/h). OSA patients were divided into mild (AHI ≥5?Results Fibrinogen levels were significantly elevated in patients with severe OSA compared to both control (P?=?0.003) and mild OSA (P?=?0.02) subjects after adjustment for covariates. However, there were no significant differences in fibrinogen levels between mild OSA and control subjects. Fibrinogen levels were directly related to AHI and arousal index and inversely related to mean and lowest oxygen saturation during sleep.

Conclusions

Severity of OSA was associated with increased fibrinogen level independent of other factors, suggesting that apneic events and oxygen desaturation during sleep are mechanisms for increased fibrinogen levels in patients with OSA.     

Gut microbiota in hypertensive patients with versus without obstructive sleep apnea

We investigated the alteration of gut microbiota and the associated metabolic risks in hypertensive patients with obstructive sleep apnea (OSA) comorbidity. Fecal and blood samples were collected from 52 hypertensive patients, who were divided into three groups: A (controls, apnea‐hypopnea index[AHI] < 5, n = 15), B (mild OSA, 5 < AHI < 20, n = 17), and C (moderate‐to‐severe OSA, AHI > 20, n = 20). The composition of the gut microbiota was studied through 16s RNA sequencing of variable regions 3–4. Analysis of the results revealed that group C had a significant higher concentration of total cholesterol, low‐density lipoprotein, and IL‐1β compared with group A. The Shannon index showed that bacterial biodiversity was lower in OSA patients. At the phylum level, the ratio of Firmicutes to Bacteroidetes (F/B) was significantly higher in group C than in groups A and B. At the genus level, the relative abundance of short‐chain fatty acids (SCFA)‐producing bacteria (e.g., Bacteroides and Prevotella) was lower while the number of inflammation‐related bacteria (e.g., Lactobacillus) was increased in patients with OSA. We found that the IL‐1β level was negatively correlated with Bacteroidetes. The area under the receiver operating characteristic curve was .672 for F/B ratio in determining hypertensive patients with OSA. In patients with hypertension, OSA was associated with worse gut dysbiosis, as evidenced by decreased levels of short‐chain fatty acids‐producing bacteria and increased number of inflammation‐related bacteria. The differences in gut microbiota discriminate hypertensive patients with OSA from those without and may result in an enhanced inflammatory response and increase the risk of metabolic diseases.     

Diaphragmatic responses to body position changes in obese patients with obstructive sleep apnea

Patients with severe obesity and obstructive sleep apnea (OSA) have been shown to have abnormalities in respiratory muscle function and respiratory control. The present study was done to evaluate diaphragmatic function and the diaphragm fiber-length-compensating reflex in morbidly obese patients with OSA (1). Twelve normal subjects and 13 morbidly obese patients with OSA were studied in recumbent and upright positions. In the normal subjects, the diaphragm fiber-length-compensating reflex operated normally causing the diaphragm's inspiratory EMG to increase when the diaphragm's fibers shortened with assumption of the upright position. However, 8 of the 13 obese patients with OSA showed a decrease rather than an increase in the inspiratory diaphragmatic EMG on assuming the upright posture. Further data indicate greater diaphragmatic efficiency in the upright than in the supine position in a majority of the obese patients, a reversal of the normal response. Two possible explanations of these observations are: an abnormality of central respiratory control in obese patients with OSA and overstretching of the diaphragm in the recumbent obese patient. The observation of reduced maximal transdiaphragmatic pressures in the recumbent position in some of the obese patients with OSA supports the second explanation. Diaphragmatic overstretching may be an important mechanism in the development of hypoventilation in the morbidly obese.     

Echocardiographic findings and plasma endothelin-1 levels in obese patients with and without obstructive sleep apnea

Sleep and Breathing - Obstructive sleep apnea (OSA) and obesity are increasingly prevalent worldwide. Both promote endothelial dysfunction contributing to systemic and pulmonary hypertension over...     

Diagnosis of obstructive sleep apnea in adults

The diagnosis of obstructive sleep apnea syndrome (OSAS) requires the combined assessment of relevant clinical features and the objective demonstration of abnormal breathing during sleep, and current evidence indicates that attempts to base the diagnosis of the clinical syndrome on either aspect alone are unreliable. The present review discusses the clinical assessment of patients with suspected OSAS and also the potential added value of structured questionnaires and clinical prediction models that seek to improve the diagnostic value of clinical assessment from the formalized evaluation of selected clinical features. While the traditional "gold standard" for objective assessment is laboratory-based polysomnography, there is growing evidence that limited sleep studies focused on respiratory and cardiac variables are adequate in most cases, and are particularly suited to home-based assessment. The choice between home versus sleep laboratory studies should be decided by taking into account resource limitations and the clinical index of suspicion for OSAS. At present, patients with either a low or high clinical index of suspicion for OSAS appear most suited to home-based investigation, whereas those with intermediate levels of clinical suspicion, or who present with atypical clinical features, may best be assessed by full polysomnographic studies in the first instance.     

Risk for obstructive sleep apnea in obese, nondiabetic adults varies with insulin resistance status

Purpose

Obstructive sleep apnea (OSA) is an increasingly common sleep disorder, especially among obese adults. Early identification of adults at risk for OSA would be of substantial benefit; however, the magnitude of the obesity epidemic requires that screening be performed judiciously. The study’s aim was to utilize questionnaires that assess OSA risk and symptoms to test the hypothesis that the most insulin-resistant subset of obese individuals is at highest risk for OSA.

Methods

Nondiabetic, overweight to obese volunteers underwent direct quantification of insulin sensitivity by measuring steady-state plasma glucose concentrations during the insulin suppression test. Insulin-sensitive and insulin-resistant individuals were administered the Berlin and STOP questionnaires to determine OSA risk status, and Epworth Sleepiness Scale (ESS) to evaluate daytime sleepiness. Fasting insulin and lipid/lipoprotein measurements were performed.

Results

Insulin-mediated glucose disposal differed threefold (p?<?0.001) between equally obese, insulin-resistant (n?=?22) and insulin-sensitive (n?=?14) individuals, associated with higher fasting insulin and triglyceride and lower high-density lipoprotein cholesterol (HDL-C) concentrations in insulin-resistant individuals. Fourteen (64 %) insulin-resistant as compared with 2 (14 %) insulin-sensitive individuals were found to be at high risk for OSA by both questionnaires (p?<?0.01). Whereas half of insulin-resistant individuals met the ESS criteria for excessive daytime sleepiness, only one insulin-sensitive individual did (p?=?0.011).

Conclusions

High risk for OSA and excessive daytime sleepiness is prevalent among the insulin-resistant subgroup of obese individuals. Surrogate estimates of insulin resistance based on fasting insulin, triglycerides, and/or HDL-C can be used to help identify those obese adults who would benefit most from OSA screening and referral for polysomnography.     

Insulin and obstructive sleep apnea in obese Chinese children

OBJECTIVE: In adults, obstructive sleep apnea (OSA) is associated with insulin resistance and dyslipidemia. We aimed to establish correlation between OSA, serum lipid profile, and insulin levels in obese snoring children. METHODS: Consecutive obese children with habitual snoring were recruited. They underwent physical examination, overnight polysomnography (PSG), and metabolic studies. OSA was diagnosed if apnea hypopnea index (AHI) > 1.0, and cases were considered to have moderate to severe OSA if AHI > 10. RESULTS: Ninety-four obese subjects with habitual snoring were studied. Seventy-three subjects were male and the median age of the studied group was 12.0 years (IQR 9.7-13.9). None of the subjects had active cardiopulmonary disease, and the BMI values of our subjects were >95th percentile using local reference charts. Sixty subjects had OSA, 47 being mild, and 13 being moderate to severe OSA. Multiple logistic regression analysis revealed that saturation nadir and insulin levels were significantly associated with OSA. CONCLUSION: OSA is prevalent among obese children with habitual snoring and insulin is independently associated with the condition. Its role in the cardiovascular complications of childhood sleep apnea is worthy of further exploration.     

Liver enzymes and histology in obese patients with obstructive sleep apnea

BACKGROUND AND AIMS: Recent studies have shown an association between obstructive sleep apnea (OSA) and elevated liver enzymes in patients with nonalcoholic fatty liver disease (NAFLD). The aim of the current study was to compare biochemical and histologic findings in patients with NAFLD as a function of OSA status. METHODS: Subjects consisted of 85 patients who had a sleep study followed by a liver biopsy performed at the time of obesity surgery. The diagnosis of OSA was based on an apnea hypopnea index of >/=15. Demographic and laboratory data were collected retrospectively. Liver biopsies were systematically evaluated for features of NAFLD including degree of steatosis, inflammation, and fibrosis. RESULTS: All but one patient had histologic evidence of NAFLD and 51% of the study population had OSA. A higher proportion of patients with OSA had elevated alanine aminotransferase levels (13/39) compared with those without OSA (3/34) (P=0.01). Only 19% of subjects had fibrosis on liver biopsy and still fewer (5%) had bridging fibrosis or cirrhosis. There was a trend toward a higher prevalence of OSA in patients with evidence of progressive liver disease, as indicated by inflammation plus fibrosis (11/15), compared with those with inflammation alone (22/48) (P=0.06). CONCLUSIONS: In obese patients with NAFLD, OSA was associated with elevated alanine aminotransferase levels and a trend toward histologic evidence of progressive liver disease.     

Prevalence of major obstructive sleep apnea syndrome symptoms in coal miners and healthy adults

Obstructive sleep apnea syndrome obstructive sleep apnea syndrome is associated with symptoms including habitual snoring, witness apnea and excessive daytime sleepiness. Also obstructive sleep apnea syndrome is related to some occupations which are needed attention for work accident. We aimed to determine the prevalence of snoring, witnessed apnea and excessive daytime sleepiness in coal workers and healthy adults in Zonguldak city center, and also evaluate the differences between these groups. This study consisted of 423 underground coal workers and 355 individuals living in centre of Zonguldak. Study and comparison group were chosen by nonstratified randomized sampling method. Data were collected by a questionnaire that included information regarding snoring, witnessed apnea and excessive daytime sleepiness. Mean age was 43.3 ± 6.05 years in miners and 44.3 ± 11.8 years in comparison group. In miners, snoring frequency was determined as 42.6%, witnessed apneas were 4.0%, and daytime sleepiness were 4.7%. In comparison group, these symptoms were 38.6%, 4.8% and 2.8% respectively. There were no statistical differences between coal workers and comparison group in these symptoms. Also snoring prevalence was higher in smoker miners. We found that major symptoms of obstructive sleep apnea syndrome in coal workers are similar to general population in Zonguldak. Further studies that constucted higher populations and with polysomnography are needed to evaluate these findings.     

CPAP increases exercise tolerance in obese subjects with obstructive sleep apnea

Obese subjects commonly suffer from exertional dyspnea and exercise intolerance. Preliminary evidence suggests that treatment with nocturnal continuous positive airway pressure (nCPAP) may improve dyspnea in obese patients with obstructive sleep apnea (OSA), but the effect on exercise tolerance is unknown. This study sought to investigate whether nCPAP improves exercise tolerance and exertional dyspnea in obese patients with OSA. Obese patients prescribed nCPAP for moderate/severe OSA and without cardiopulmonary disease were recruited. Patients completed a constant-load exercise test and Baseline and Transitional Dyspnea Index questionnaires (BDI/TDI) at baseline and after one and three months of nCPAP. Primary outcome was change in constant-load exercise time from baseline to one and three months. Secondary outcomes included changes in isotime dyspnea, isotime leg fatigue and BDI/TDI score at one and three months. Fifteen subjects (body mass index?=?43?kg?m(-2), apnea-hypopnea index?=?49(.)hr(-1)) were studied. Constant-load exercise time increased by 2.0?min (40%, p?=?0.02) at one month and 1.8?min (36%, p?=?0.04) at three months. At one and three months, isotime dyspnea decreased by 1.4 (p?=?0.17) and 2 units (p?=?0.04), and leg fatigue decreased by 1.2 (p?=?0.18) and 2 units (p?=?0.02), respectively. BDI/TDI scores were 2.7 (p?=?0.001) and 4.5 points (p?相似文献   

Cephalometric analysis in obese and nonobese patients with obstructive sleep apnea syndrome

STUDY OBJECTIVES: The aims of this study were to comprehensively evaluate the cephalometric features of patients with obstructive sleep apnea syndrome (OSAS), and to elucidate the relationship between cephalometric variables and severity of the apnea-hypopnea index (AHI). PATIENTS: The study population consisted of 62 male patients with OSAS, classified into 33 obese patients (body mass index [BMI] >or= 27) and 29 nonobese patients (BMI < 27), and 13 male simple snorers (AHI < 5 events per hour). METHOD: and measurements: Diagnostic polysomnography and measurements of 22 cephalometric variables were carried out for all patients and simple snorers. RESULTS: Patients with OSAS in both subgroups showed several significant cephalometric features compared with simple snorers: (1) inferiorly positioned hyoid bone, (2) enlarged soft palate, and (3) reduced upper airway width at soft palate. More extensive and severe soft-tissue enlargements including anteriorly positioned hyoid bone and a longer tongue were found in the obese patients. In the nonobese patients, the anteroposterior distances of the bony nasopharynx and oropharynx were significantly smaller than those of simple snorers and obese patients. Stepwise regression analysis showed that anterior displacement of the hyoid bone and retroposition of the mandible were the dominant overall determinants for AHI in patients with OSAS, and that narrowing of the bony oropharynx and inferior displacement of the hyoid bone were dominant determinants for AHI in nonobese patients. A significant regression model for AHI using cephalometric variables could not be obtained for the obese patients, but the BMI proved to be the most significant determinant. CONCLUSION: Characteristics of the craniofacial bony structure such as narrowing of the nasopharynx and oropharynx and enlargement of the soft tissue in the upper airway may be important risk factors for the development of OSAS in nonobese patients. In obese patients, the deposition of adipose tissue in the upper airway may aggravate the severity of OSAS.     

Flow-volume curves in snoring patients with and without obstructive sleep apnea

To examine the usefulness of flow-volume curves as a screening test for the diagnosis of obstructive sleep apnea (OSA), we studied 405 consecutive patients referred for evaluation of possible OSA. All patients had full pulmonary function studies, which included measurements of maximal inspiratory and expiratory flow-volume curves, and nocturnal polysomnography, including continuous monitoring of snoring sounds. When the results were analyzed, of the 405 patients studied, 207 had OSA (apnea/hypopnea index [AHI] greater than 10) and 198 did not. Flow-volume curves were examined for the presence of upper airway obstruction defined as midvital capacity flow ratio (MVCFR = ratio of the maximal expiratory flow at 50% of vital capacity to maximal inspiratory flow at 50% of vital capacity) greater than 1.0. We found no significant difference in the values of MVCFR between the two groups: MVCFR was equal to 0.69 +/- 0.31 for nonapneic snorers, and 0.68 +/- 0.29 for the apneic snorers. Furthermore, we redefined the apneic and nonapneic groups using different cutoff values of AHI: 20, 30, 40, and 50. Independently of the AHI cutoff used, we found no significant difference in the MVCFR between the two groups. Linear regression analysis for the entire group of 405 patients revealed no significant correlation between MVCFR and the AHI or the snoring indices. We calculated the sensitivity, specificity, and predictive values of MVCFR for the diagnosis of OSA. We found that this test had 12% sensitivity, 86% specificity, 47% positive predictive value, and 46% negative predictive value.(ABSTRACT TRUNCATED AT 250 WORDS)     

Overnight fluid shifts in subjects with and without obstructive sleep apnea

Objective

To investigate the characteristics of baseline body fluid content and overnight fluid shifts between non-obstructive sleep apnea (non-OSA) and obstructive sleep apnea (OSA) subjects.

Methods

A case-controlled study was performed between February 2013 and January 2014, with 36 (18 OSA and 18 non-OSA) outpatients enrolled in this study. Polysomnographic parameters and results of body fluid were compared between the two groups.

Results

There were no differences in age, weight, and body mass index (BMI) between groups. Compared with the non-OSA group, OSA group had significantly higher neck circumference (NC) and fluid volume shift in the legs. OSA patients had higher left and right leg fluid indices than non-OSA subjects. There were significant correlations between apnoea-hypopnoea index and baseline fluid indices in both legs as well as the reduction in overnight change in both legs fluid volume. The increase in NC was also significantly correlated with the reduction in overnight change in both legs fluid volume, but not with the change in head and neck fluid volume. There were significant correlations between change in NC and increased fluid shifts in head and neck volume.

Conclusions

OSA patients had a higher baseline fluid content in both legs as compared with non-OSA subjects, which may be the basic factor with regards to fluid shifts in OSA patients. The increase in head and neck fluid shift volume did not directly correlate with the severity of OSA.     

Pharyngeal compliance in snoring subjects with and without obstructive sleep apnea

Recent studies have demonstrated a reduction in pharyngeal cross-sectional area and in upper airway muscle tone in patients with obstructive sleep apnea. These findings suggest that the pharynx in such patients may be more compliant than normal even in the awake state. We have tested this hypothesis by examining the pressure-area relationship of the pharynx in 13 patients and in 7 control subjects. Measurements were performed during wakefulness, with the subject seated, and at a constant lung volume near functional residual capacity. Pharyngeal area was measured by an acoustic reflection technique. Pharyngeal pressure was varied by having the subject perform gradual inspiratory and expiratory isovolume maneuvers against a distally occluded airway while mouth pressure was recorded. Specific compliance of the pharynx was calculated as the fractional change in pharyngeal area between a pressure of 0 and -10 cm H2O and and between 0 and 10 cm H2O. Specific pharyngeal compliance was 0.036 +/- 0.004 cm H2O-1 (mean +/- SE) in the control group and 0.094 +/- 0.012 cm H2O-1 in patients with OSA (p less than 0.01). These findings indicate that patients with obstructive sleep apnea have increased pharyngeal compliance. This abnormality predisposes to pharyngeal occlusion during sleep when negative transmural pressures are generated in the pharynx.     

Association between REM sleep and obstructive sleep apnea in obese and overweight adolescents

Sleep and Breathing - Overweight and obese children have demonstrated reduced rapid eye movement (REM) sleep, affecting energy balance regulation and predisposition to weight gain. Obstructive...     

Lung volume-related changes in the pharyngeal area of obese females with and without obstructive sleep apnoea

The majority of male patients with obstructive sleep apnoea (OSA) have an abnormal pharyngeal structure and function, with episodic complete airway occlusion during sleep. Since OSA is less common in females than in males, it is possible that other abnormalities are active in female patients with OSA. Consequently, we measured pharyngeal area and its lung volume-related changes (LVRC) from functional residual capacity (FRC) to residual volume (RV) in overweight females, 14 with OSA and 14 without OSA. Pharyngeal areas were measured using the acoustic reflection technique. While there were no significant differences in pharyngeal area between the OSA and control groups at either FRC (mean +/- SD, 3.49 +/- 0.46 cm2 vs 3.08 +/- 0.63 cm2) or RV (2.86 +/- 0.47 cm2 vs 2.67 +/- 0.49 cm2), the reduction in pharyngeal area between FRC and RV was significantly greater in the OSA group (0.63 +/- 0.23 cm2 vs 0.33 +/- 0.32 cm2, p less than 0.05). Furthermore, although the expiratory reserve volume (ERV) was not significantly different between the two groups (0.4 +/- 0.2 l vs 0.4 +/- 0.3 l), LVRC, defined as the reduction in pharyngeal area normalized by ERV, was significantly higher in the females with OSA than in the non-apnoeic controls (2.68 +/- 2.24 cm2.l-1 vs 1.17 +/- 1.23 cm2.l-1, p less than 0.02). We conclude that females with OSA have abnormal pharyngeal mechanics similar to males with OSA.     

Comparison of upper airway collapse patterns and its clinical significance: drug-induced sleep endoscopy in patients without obstructive sleep apnea,positional and non-positional obstructive sleep apnea

Purpose

To compare patient characteristics, upper airway (UA) collapse patterns and treatment outcome in obstructive sleep apnea (OSA) patients, including non-positional OSA patients (NPP) and positional OSA patients (PP), and non-OSA.

Methods

Cohort study of patients screened for OSA in 2012. Polysomnography was performed and UA was evaluated using the VOTE classification during drug-induced sleep endoscopy (DISE). Treatment outcome of MAD and UA surgery was evaluated.

Results

Eight hundred sixty patients were included. Higher BMI, larger neck circumference, and greater age were independent significant predictors for OSA. DISE was performed in 543 patients: 119 non-OSA and 424 OSA patients of whom 257 PP and 167 NPP patients. PP were younger, had smaller neck circumference, lower BMI and apnea-hypopnea index (AHI) than NPP. Collapse at velum (p?<?0.001) and oropharynx (p?<?0.001) significantly increased the odds for having OSA. Tongue base and epiglottis collapse were, on group level, not determinative for OSA or non-OSA. Complete concentric collapse (CCC) was observed less frequently in PP (31.5%) as compared to NPP (46.1%). After UA surgery, OSA often was cured or improved to less severe positional OSA. Lower efficacy of UA surgery was observed in PP as compared to NPP. No differences were observed in MAD treatment outcome.

Conclusions

Current study provides insight in patients screened for OSA: collapse at velum and oropharynx significantly determined presence of OSA and CCC occurred less frequently in PP compared to NPP. In addition, residual positional dependency is common after UA surgery. More trials are needed to gain insight in pathophysiology and treatment outcome.

     

Indications for treatment of obstructive sleep apnea in adults

Obstructive sleep apnea is associated with significant daytime sleepiness, reduced quality of life, insulin resistance, motor vehicle crashes, vascular morbidity and mortality. Current evidence supports the belief that all these parameters can be impacted favorably by treatment. Medical therapy with positive pressure eliminates snoring and favorably affects daytime sleepiness, driving risk, vascular function, vascular risk, and quality of life. Treatment may be difficult to accept or adhere to, and some treatment options are not uniformly effective. The long-term impact of treatment is uncertain.