Background-Aim. Although sleep disturbance is a common complaint among patients of all ages, research suggests that older adults are particularly vulnerable. The aim of this retrospective study was to elucidate the influence of age on clinical characteristics and polysomnographic findings of obstructive sleep apnea syndrome (OSAS) between elderly and younger male patients in a Greek population. Methods. 697 male patients with OSAS were examined from December 2001 to August 2011. All subjects underwent an attended overnight polysomnography (PSG). They were divided into two groups: young and middle-aged (<65 years old) and elderly (≥65 years old). We evaluated the severity of OSAS, based on apnea-hypopnea index (AHI), and the duration of apnea-hypopnea events, the duration of hypoxemia during total sleep time (TST) and during REM and NREM sleep, and the oxygen saturation in REM and in NREM sleep. Results. PSG studies showed that elderly group had significant higher duration of apnea-hypopnea events, longer hypoxemia in TST and in NREM sleep, as well as lower oxygen saturation in REM and NREM sleep than the younger group. Otherwise, significant correlation between BMI and neck circumference with AHI was observed in both groups. Conclusions. The higher percentages of hypoxemia during sleep and longer duration of apnea-hypopnea events that were observed in the elderly group might be explained by increased propensity for pharyngeal collapse and increased deposition of parapharyngeal fat, which are associated with aging. Another factor that could explain these findings might be a decreased partial arterial pressure of oxygen (PaO2) due to age-related changes in the respiratory system.
Rationale: Obstructive sleep apnea (OSA) has been associated with a higher prevalence and severity of the metabolic syndrome in adult patients, even after controlling for obesity. In contrast, OSA in prepubertal children does not appear to correlate with the magnitude of such metabolic derangements.
Objectives: To further establish the potential mechanistic role of OSA in metabolic regulation in prepubertal children.
Methods: Fasting glucose, insulin, C-reactive protein, apolipoprotein B, and serum lipid concentrations were determined during the initial polysomnographic diagnosis of OSA and 6–12 months after adenotonsillectomy in both obese and nonobese children.
Measurements and Main Results: Sixty-two children with OSA (37 obese and 25 nonobese), age 7.40 ± 2.6 years (mean ± SD) completed the study. After adenotonsillectomy, significant improvements in apnea–hypopnea index and sleep fragmentation occurred, particularly among nonobese children. In nonobese children, adenotonsillectomy was associated with mild increases in body mass index z scores, no changes in either fasting glucose or insulin, significant increases in high-density lipoprotein and reciprocal decreases in low-density lipoprotein, and reductions in plasma C-reactive protein and apolipoprotein B levels. In obese children, adenotonsillectomy did not result in body mass index or glucose changes, but was associated with marked improvements in all other measures.
Conclusions: OSA does not appear to induce insulin resistance in nonobese pediatric patients but seems to play a significant role in obese patients. The significant improvements in lipid profiles, C-reactive protein, and apolipoprotein B after adenotonsillectomy in the two groups suggest a pathogenic role for OSA in lipid homeostasis and systemic inflammation independent of the degree of adiposity.
obstructive sleep apnea; inflammation; obesity; serum lipids; diabetes
The aims of this study were 1) to evaluate the effect of isolated uvulopalatopharyngoplasty (UPPP) on subjective obstructive sleep apnea (OSA) symptoms in adult patients regardless of the response to surgery, and ultimately 2) to investigate the differences in changes in subjective OSA symptoms between successful and unsuccessful surgery groups.
Twenty consecutive adult patients who underwent isolated UPPP were enrolled. Pre- and postoperative subjective OSA symptoms (snoring, witnessed apnea, daytime sleepiness, morning headache, daytime fatigue, restless sleep, difficulty with morning arousal) and polysomnographic data were evaluated in all subjects. Changes in subjective OSA symptoms before and after surgery were investigated in the successful (n=11) and unsuccessful (n=9) groups. Surgical success was defined as a reduction of at least 50% in the preoperative apnea-hypopnea index (AHI) and a postoperative AHI less than 20 per hour.
After isolated UPPP, all subjective OSA symptoms changed significantly in the patients, especially in the successful group. In the unsuccessful group, snoring, witnessed apnea and daytime fatigue changed significantly, while other symptoms did not change significantly after surgery.
Isolated UPPP may improve subjective OSA symptoms in adult patients whom surgery was successful or unsuccessful. However, after isolated UPPP, the improvements in subjective OSA symptoms in the unsuccessful group may be different from those in the successful group.
Adult; Obstructive sleep apnea; Polysomnography; Surgery; Symptom
The Epworth Sleepiness Scale (ESS) is often used in the evaluation of obstructive sleep apnea (OSA), though questions remain about the influence gender, ethnicity, and body morphometry have in the responses to this questionnaire. The aim of this study was to examine differences in ESS scores between various demographic groups of patients referred for polysomnography, and the relationship of these score to sleep-disordered breathing
Nineteen hundred consecutive patients referred for polysomnographic diagnosis of OSA completed questionnaires, including demographic data and ESS. OSA was determined based on a respiratory disturbance index (RDI) ≥15 by polysomnography.
In this high risk population for OSA, the ESS was 10.7 ± 5.6. The highest ESS scores were seen in obese males; non-obese females and non-obese Caucasian males scored the lowest. ESS was weakly correlated with RDI (r = 0.17, P < 0.0001). The sensitivity of ESS for the diagnosis of OSA was 54% and the specificity was 57%. The positive (PPV) and negative (NPV) predictive values were 64% and 47%, respectively. In obese subjects, the sensitivity and specificity were 55% and 53%, compared with 47% and 63% in non-obese subjects. In obese, Hispanic males, the sensitivity, specificity, and PPV were 59%, 54%, and 84%, respectively. In non-obese, Caucasian females, the sensitivity, specificity, and NPV were 43%, 59%, and 72%.
The ESS appears to be affected by many factors, including gender, ethnicity, and body morphometry. The ability of the ESS to predict OSA is modest, despite a significant correlation with the severity of OSA. The test characteristics improve significantly when applied to select populations, especially those at risk for OSA.
Ethnicity; gender; obstructive sleep apnea; epworth sleepiness scale; screening.
Obstructive sleep apnea (OSA) as well as obesity is associated with increased production of reactive oxygen species (ROS). Neutrophils produce great amounts of ROS. The aim was to evaluate peripheral blood neutrophils ROS production in men with OSA and to establish relations with disease severity and obesity. Methods. Forty-six men with OSA and 10 controls were investigated. OSA was confirmed by polysomnography (PSG), when apnea/hypopnea index was >5/h. Body mass index (BMI) was evaluated. Neutrophils were isolated from peripheral blood in the morning after PSG. Dihydrorhodamine-123 was used for ROS detection. Data is presented as median (25th and 75th percentiles). All subjects were divided into four groups: nonobese mild-to-moderate OSA, obese mild-to-moderate OSA, nonobese severe OSA, and obese severe OSA. Results. Neutrophil ROS production was higher in nonobese severe OSA group compared to nonobese mild-to-moderate OSA (mean fluorescence intensity (MFI) 213.4 (89.0–238.9) versus 44.5 (20.5–58.4), P < 0.05). In obese patient groups, ROS production was more increased in severe OSA compared to mild-to-moderate OSA group (MFI 74.5 (47.9–182.4) versus 31.0 (14.8–53.8), P < 0.05). It did not differ in the groups with different BMI and the same severity of OSA. Conclusion. Increased neutrophil ROS production was related to more severe OSA but not obesity.
Biomarkers of adipose tissue may affect glucose and lipid metabolism and present pro-inflammatory properties, thus could be involved in the pathobiochemistry of cardiovascular disease (CVD). The coexistence of sleep apnea syndrome (OSA) and metabolic risk factors of CVD is worth explaining. The aim of the study was to compare the serum adipocytokines in subjects with and without OSA, who had all elevated body mass index (BMI).
Overweight (BMI: 25.0-29.9 kg/m2) and obese (BMI: 30.0-39.9 kg/m2) OSA-suspected Caucasian males, aged 30-63, with no acute disease or chronic disorder underwent polysomnographic evaluation to select OSA-positive (AHI ≥ 5) and OSA-negative (AHI < 5) subjects. Four subgroups were created of 18 persons each: Over(weight)-OSA-Neg, Over-OSA-Pos, Obese-OSA-Neg, Obese-OSA-Pos. In all subjects, plasma carbohydrate and lipid metabolism parameters, and serum uric acid, resistin and leptin concentrations were determined.
A decreased resistin level was observed in Over-OSA-Pos vs. Over-OSA-Neg subjects (P = 0.037) as well as in Obese-OSA-Pos vs. Obese-OSA-Neg (P = 0.045). No differences in leptin concentrations were observed. A positive correlation between leptin and BMI was in both overweight subgroups and a negative one between resistin and fasting glucose was in both obese subgroups.
OSA may decrease the serum resistin level in subjects with excess body mass and also may contribute to glucose metabolism, but has no influence on the leptin level.
obstructive sleep apnea; body mass index; adipocytokines; leptin; resistin
The erythrocyte sedimentation rate (ESR) is a marker for inflammation, and it has been identified as a risk factor for atherothrombotic cardiovascular disease. The aim of this study was to determine the relationship between the plasma ESR level and nocturnal oxygen desaturation or other polysomnographic variables and to examine the role of obesity in patients with obstructive sleep apnea syndrome (OSAS).
This retrospective study included 72 patients with a diagnosis of OSAS who underwent overnight polysomnography and routine blood tests between July and December of 2005. We compared the plasma ESR level with the sum of all the polysomnographic variables and divided the patient group into obese and non-obese patients.
The mean ESR level was 8.45 mm/hr. There was a significant difference in the ESR level between genders (P<0.001). A significant correlation was found between the percentage of time spent at a SpO2 below 90% and the ESR level in the obese group (BMI ≥25, N=43, P=0.012). In addition, the ESR levels had a positive correlation with age in the obese group (P=0.002). However, there was no significant correlation with the percentage of time spent at a SpO2 below 90% in the whole group of patients and in the non-obese group (BMI <25, N=29). The ESR level showed no correlation with the other polysomnographic variables.
The duration of deoxygenation in obese patients with OSAS may be associated with the ESR level which is an independent predictor of cardiovascular disease.
Blood sedimentation; Obstructive sleep apnea; Oximetry; Polysomnography
The purpose of this study was to identify the regions of the brain associated with recurrent nocturnal chronic hypoxic episodes in patients with untreated obstructive sleep apnea syndrome (OSAS) using low-resolution electromagnetic tomography (LORETA) and quantitative electroencephalography (QEEG).
Nocturnal polysomnograph (NPSG) and subsequent morning electroencephalograph (EEG) were measured in 20 subjects with OSAS. Mild (n=10 ages 39.5±12.1 years) and severe (n=10 ages 41.7±13.6 years) right-handed male OSAS subjects were selected by interview and questionnaires including the NPSG, Beck Depression Inventory, Beck Anxiety Inventory, Epworth Sleepiness Scale, and Pittsburgh Sleep Quality Index. The LORETA and QEEG were compared between the severe and mild OSAS groups by frequency bands (delta 1-3 Hz, theta 4-7 Hz, alpha 8-12 Hz, beta1 13-18 Hz, beta2 19-21 Hz, beta3 22-30 Hz, and total 1-30 Hz) made by spectral analysis during resting with the eyes closed.
The LORETA analysis showed decreased alpha activity at the right posterior cingulate gyrus (Brodmann area 23) in cases with severe OSAS compared to mild OSAS (p<0.05). For the QEEG, the absolute power of the alpha activity (8-12 Hz) was decreased in P3 (p=0.047), PZ (p=0.039) and O2 (p=0.04) in cases with severe OSAS compared to mild OSAS cases. The LORETA and QEEG analyses had similar results with regard to band, activation and location.
The decreased activity of the alpha frequency in the right posterior cingulate gyrus, in patients with severe OSAS compared to those with mild OSAS, suggests that chronic repeated short-term hypoxia during sleep, in OSAS, could provoke cortical brain dysfunction associated with cognitive dysfunction such as memory and attention.
Obstructive sleep apnea syndrome; Low-resolution electromagnetic tomography; Quantitative electroencephalography; Hypoxic brain damage
Rates of cardiac arrhythmias increase with age and may be associated with clinically significant morbidity. We studied the association between sleep-disordered breathing (SDB) with nocturnal atrial fibrillation or flutter (AF) and complex ventricular ectopy (CVE) in older men.
A total of 2911 participants in the Outcomes of Sleep Disorders in Older Men Study underwent unattended polysomnography. Nocturnal AF and CVE were ascertained by electrocardiogram-specific analysis of the polysomnographic data. Exposures were (1) SDB defined by respiratory disturbance index (RDI) quartile (a major index including all apneas and hypopneas), and ancillary definitions incorporating (2) obstructive events, obstructive sleep apnea (OSA; Obstructive Apnea Hypopnea Index quartile), or (3) central events, central sleep apnea (CSA; Central Apnea Index category), and (4) hypoxia (percentage of sleep time with <90% arterial oxygen percent saturation). Multivariable logistic regression analyses were performed.
An increasing RDI quartile was associated with increased odds of AF and CVE (P values for trend, .01 and <.001, respectively). The highest RDI quartile was associated with increased odds of AF (odds ratio [OR], 2.15; 95% confidence interval [CI], 1.19–3.89) and CVE (OR, 1.43; 95% CI, 1.12–1.82) compared with the lowest quartile. An increasing OSA quartile was significantly associated with increasing CVE (P value for trend, .01) but not AF. Central sleep apnea was more strongly associated with AF (OR, 2.69; 95%CI, 1.61–4.47) than CVE (OR, 1.27; 95% CI, 0.97–1.66). Hypoxia level was associated with CVE (P value for trend, <.001); those in the highest hypoxia category had an increased odds of CVE (OR, 1.62; 95% CI, 1.23–2.14) compared with the lowest quartile.
In this large cohort of older men, increasing severity of SDB was associated with a progressive increase in odds of AF and CVE. When SDB was characterized according to central or obstructive subtypes, CVE was associated most strongly with OSA and hypoxia, whereas AF was most strongly associated with CSA, suggesting that different sleep-related stresses may contribute to atrial and ventricular arrhythmogenesis in older men.
There are several treatments for obstructive sleep apnea syndrome, such as weight loss, use of an oral appliance and continuous positive airway pressure, that can be used to reduce the signs and symptoms of obstructive sleep apnea syndrome. Few studies have evaluated the effectiveness of a physical training program compared with other treatments. The aim of this study was to assess the effects of physical exercise on subjective and objective sleep parameters, quality of life and mood in obstructive sleep apnea patients and to compare these effects with the effects of continuous positive airway pressure and oral appliance treatments.
Male patients with moderate to severe obstructive sleep apnea and body mass indices less than 30 kg/m2 were randomly assigned to three groups: continuous positive airway pressure (n = 9), oral appliance (n = 9) and physical exercise (n = 7). Polysomnographic recordings, blood samples and daytime sleepiness measurements were obtained prior to and after two months of physical exercise or treatment with continuous positive airway pressure or an oral appliance. Clinicaltrials.gov: NCT01289392
After treatment with continuous positive airway pressure or an oral appliance, the patients presented with a significant reduction in the apnea-hypopnea index. We did not observe changes in the sleep parameters studied in the physical exercise group. However, this group presented reductions in the following parameters: T leukocytes, very-low-density lipoprotein and triglycerides. Two months of exercise training also had a positive impact on subjective daytime sleepiness.
Our results suggest that isolated physical exercise training was able to modify only subjective daytime sleepiness and some blood measures. Continuous positive airway pressure and oral appliances modified the apnea-hypopnea index.
Obstructive Sleep Apnea; CPAP; OA; Exercise Training; Subjective Daytime Sleepiness; Polysomnography
Enhanced characterization of sleep architecture, compared with routine polysomnographic metrics such as stage percentages and sleep efficiency, may improve the predictive phenotyping of fragmented sleep. One approach involves using stage transition analysis to characterize sleep continuity.
Methods and Principal Findings
We analyzed hypnograms from Sleep Heart Health Study (SHHS) participants using the following stage designations: wake after sleep onset (WASO), non-rapid eye movement (NREM) sleep, and REM sleep. We show that individual patient hypnograms contain insufficient number of bouts to adequately describe the transition kinetics, necessitating pooling of data. We compared a control group of individuals free of medications, obstructive sleep apnea (OSA), medical co-morbidities, or sleepiness (n = 374) with mild (n = 496) or severe OSA (n = 338). WASO, REM sleep, and NREM sleep bout durations exhibited multi-exponential temporal dynamics. The presence of OSA accelerated the “decay” rate of NREM and REM sleep bouts, resulting in instability manifesting as shorter bouts and increased number of stage transitions. For WASO bouts, previously attributed to a power law process, a multi-exponential decay described the data well. Simulations demonstrated that a multi-exponential process can mimic a power law distribution.
Conclusion and Significance
OSA alters sleep architecture dynamics by decreasing the temporal stability of NREM and REM sleep bouts. Multi-exponential fitting is superior to routine mono-exponential fitting, and may thus provide improved predictive metrics of sleep continuity. However, because a single night of sleep contains insufficient transitions to characterize these dynamics, extended monitoring of sleep, probably at home, would be necessary for individualized clinical application.
Obstructive sleep apnea (OSA) is a common yet underdiagnosed condition. The aim of our study is to test whether prediabetes and type 2 diabetes are associated with obstructive sleep apnea (OSA) in extremely obese (BMI ≥ 40 kg/m2) subjects.
One hundred and thirty seven consecutive extremely obese patients (99 females) from a controlled clinical trial [MOBIL-study (Morbid Obesity treatment, Bariatric surgery versus Intensive Lifestyle intervention Study) (ClinicalTrials.gov number NCT00273104)] underwent somnography with Embletta® and a 2-hour oral glucose tolerance test (OGTT). OSA was defined by an apnea-hypopnea index (AHI) ≥ 5 events/hour. Patients were categorized into three groups according to criteria from the American Diabetes Association: normal glucose tolerance, pre-diabetes and type 2 diabetes. Multiple logistic regression analysis was used to identify possible determinants of OSA.
The patients had a mean (SD) age of 43 (11) years and a body mass index (BMI) of 46.9 (5.7) kg/m2. Males had significantly higher AHI than females, 29 (25) vs 12 (17) events/hour, p < 0.001. OSA was observed in 81% of men and in 55% of women, p = 0.008. Twenty-nine percent of subjects had normal glucose tolerance, 42% had pre-diabetes and 29% had type 2 diabetes. Among the patients with normal glucose tolerance 33% had OSA, while 67% of the pre-diabetic patients and 78% of the type 2 diabetic patients had OSA, p < 0.001. After adjusting for age, gender, BMI, high sensitive CRP and HOMA-IR, both pre-diabetes and type 2 diabetes were still associated with OSA, odds ratios 3.18 (95% CI 1.00, 10.07), p = 0.049 and 4.17 (1.09, 15.88), p = 0.036, respectively. Mean serum leptin was significantly lower in the OSA than in the non-OSA group, while other measures of inflammation did not differ significantly between groups.
Type 2 diabetes and pre-diabetes are associated with OSA in extremely obese subjects.
MOBIL-study (Morbid Obesity treatment, Bariatric surgery versus Intensive Lifestyle intervention Study) (ClinicalTrials.gov number NCT00273104)
Obstructive sleep apnea; type 2 diabetes; prediabetes; oral glucose tolerance test; inflammation
Obstructive sleep apnea (OSA) is a common but usually under-diagnosed sleep disorder. Objective diagnosis is based on polysomnography, which is an expensive test. We assessed the reliability and diagnostic accuracy of the Berlin questionnaire (BQ) in diagnosis of OSA in Iranian sleep clinic patients.
A cross-sectional linguistic validation study was conducted on consecutive Iranian patients with Persian language attending one sleep clinic in Isfahan (Iran) were studied. Patients completed the Persian BQ (contains 10 questions in 3 categories), developed by forward-backward translation method. The patients underwent an overnight polysomnographic study at the clinic. Apneas/hypopnea index of >5/Hour was considered for diagnosis of OSA.
One hundred and fifty seven patients (55.4% male, mean age = 52.3 ± 13.6 years) were evaluated. Sleep study confirmed OSA diagnosis in 91.7% of the studied patients. The reliability analysis of the BQ categories showed alpha Cronbach's as 0.70 and 0.50 for category 1 and category 2, respectively. BQ categories 1-3 were positive respectively in 88.5%, 67.5%, and 66.9% of the patients. The BQ and sleep study were in agreement for 82.1% of the cases. The sensitivity, specificity, positive and negative predictive values, and positive, and negative likelihood ratio of the BQ were calculated as 84.0%, 61.5%, 96.0%, 25.8%, 2.18%, and 0.26% respectively.
BQ is useful as a screening test for diagnosing OSA in Iranian patients with sleep complaints; however, the test cannot be used for rolling out the OSA. Further studies on editing, modifying, and applying the BQ in a larger sample of patients are warranted in our society.
Apnea hypopnea index; Berlin questionnaire; obstructive sleep apnea; Persian version of Berlin questionnaire; reliability and validity
The relationship between obstructive sleep apnea (OSA) and cardiovascular disease is intensively discussed. Endothelial leukocyte adhesion molecule (E-selectin) is one of factors facilitating leukocyte migration to the subendothelial layer which could be considered proatherogenic. The aim of the study was to determine E-selectin levels and total plasma antioxidant status (TAS) in the blood of different stage OSA patients.
Non-smoking, OSA-suspected males, aged 30-63, were selected for the study. An EMBLA polysomnographic system was used to establish the severity of apneic episodes. The results of apnea/hypopnea index (AHI) allowed dividing patients into the following groups: OSA-0 with AHI 0-4.9 (n = 14), OSA-1 with AHI 5-15 (n = 14), OSA-2 with AHI 16-30 (n = 13), OSA-3 with AHI ≥ 30 (n = 13). Complete blood count (CBC), glycemia during oral glucose tolerance test, fasting plasma lipid profile, uric acid, and high sensitivity C-reactive protein (hsCRP) were estimated among routine parameters. We determined plasma concentrations of E-selectin and total antioxidant status.
We found progressively decreasing concentrations of TAS (P = 0.03) and increased concentrations of E-selectin (P = 0.0001) from OSA-0 to OSA-3 subjects. No correlation between E-selectin and metabolic parameters was noted.
In the studied OSA groups, E-selectin appeared an independent proatherogenic factor.
obstructive sleep apnea; total antioxidant status; endothelium; E-selectin
BACKGROUND AND OBJECTIVE:
Uvulopalatopharyngoplasty (UPPP) is a commonly used surgical technique for oropharyngeal reconstruction in patients with obstructive sleep apnea (OSA). This procedure can be done either through the classic or the laser-assisted uvulopalatopharyngoplasty (LAUP) technique. The purpose of this study was to evaluate the effect of classic UPPP and LAUP on acoustics of voice and speech nasalance, and to compare the effect of each operation on these two domains.
PATIENTS AND METHODS:
The study included 27 patients with a mean age of 46 years. All patients were diagnosed with OSA based on polysomnographic examination. Patients were divided into two groups according to the type of surgical procedure. Fifteen patients underwent classic UPPP, whereas 12 patients were subjected to LAUP. A full assessment was done for all patients preoperatively and postoperatively, including auditory perceptual assessment (APA) of voice and speech, objective assessment using acoustic voice analysis and nasometry.
Auditory perceptual assessment of speech and voice, acoustic analysis of voice and nasometric analysis of speech did not show statistically significant differences between the preoperative and postoperative evaluations in either group (P>.05).
The results of this study demonstrated that in patients with OSA, the surgical technique, whether classic UPPP or LAUP, does not have significant effects on the patients’ voice quality or their speech outcomes.
Periodic limb movements (PLMs) and obstructive sleep apnea (OSA) may present as overlapping conditions. This study investigated the occurrence of PLM during continuous positive airway pressure (CPAP) titration, with the hypothesis that the presence of PLM during CPAP represented “unmasking” of a coexisting sleep disorder.
A total of 78 polysomnographic recordings in 39 OSA subjects with an hourly PLM index ≥5 during CPAP application were evaluated.
Application of CPAP significantly improved sleep architecture without change in the PLM index when compared with baseline. The PLM indices and PLM arousal indices were linearly correlated during both nights (r = 0.553, P < 0.01; r = 0.548, P < 0.01, respectively). Eleven subjects with low PLM indices at baseline had greater changes in the PLM index as compared with the sample remainder (P = 0.004). Sixteen subjects with significantly lower PLM indices at baseline required optimal CPAP levels higher than the sample average of 8.2 cm H2O (P = 0.032). These subjects also showed significantly higher median apnea–hypopnea index (AHI) at baseline than the sample remainder (74.4 events per hour [range: 24.2–124.4 events per hour] vs. 22.7 events per hour [range: 8.6–77.4 events per hour], respectively, P < 0.001).
These findings suggest that PLM seen during CPAP titration may be related to a concurrent sleep disorder because of “unmasking” in patients with treated OSA.
Periodic limb movements (PLM); Obstructive sleep apnea (OSA); Continuous positive airway pressure (CPAP); Sleep disorders; Polysomnography
Obstructive sleep apnea (OSA) has been associated with increased systemic inflammatory responses that may contribute to an increased risk for end-organ morbidity. The changes in levels of pro-inflammatory cytokine IL-6 , and the anti-inflammatory cytokine IL-10, both of which play a major role in atherogenesis, a major consequence of OSA, have not specifically been assessed in pediatric patients.
Consecutive non-obese children (aged 4–9 years) who were polysomnographically diagnosed with OSA, and age-, gender-, ethnicity-, and BMI- matched control children underwent a blood draw the next morning after a sleep study and plasma samples were assayed for interleukins 6 (IL-6) and 10 (IL-10). These tests were repeated 4–6 months after adenotonsillectomy (T&A) in children with OSA.
IL-6 levels were higher and IL-10 plasma levels were lower in children with OSA and returned to control levels after T&A.
Systemic inflammation is a constitutive component and consequence of OSA in many children, even in the absence of obesity, and is reversible upon treatment in most patients.
obstructive sleep apnea; inflammation; cytokines; atherogenesis; interleukin 10; interleukin 6
Obstructive sleep apnea (OSA) is a common disorder that is associated with significant morbidity. Veterans may be at an elevated risk for OSA because of increased prevalence of factors associated with the development and progression of OSA. The objective of this study was to determine the clinical characteristics, comorbidities, polysomnographic findings, and response to treatment of veterans with OSA.
We performed a retrospective chart review of 596 patients undergoing polysomnography at the Cincinnati Veterans Affairs Medical Center from February 2005 through December 2007. We assessed potential correlations of clinical data with polysomnography findings and response to treatment.
Polysomnography demonstrated OSA in 76% of patients; 30% had mild OSA, 23% moderate OSA, and 47% severe OSA. Increasing body mass index, neck circumference, Epworth Sleepiness Scale score, hypertension, congestive heart failure, and type 2 diabetes correlated with increasing OSA severity. Positive airway pressure treatment was initiated in 81% of veterans with OSA, but only 59% reported good adherence to this treatment method. Of the patients reporting good adherence, a greater proportion of those with severe OSA (27%) than with mild or moderate disease (0%-12%) reported an excellent response to treatment.
The prevalence of metabolic and cardiovascular comorbidities increased with increasing OSA severity. Only 59% of treated patients reported good adherence to treatment with positive airway pressure, and response to treatment correlated with OSA severity.
Objective. This study examined the association between obstructive sleep apnea (OSA), daytime sleepiness, functional activity, and objective physical activity. Setting. Subjects (N = 37) being evaluated for OSA were recruited from a sleep clinic. Participants. The sample was balanced by gender (53% male), middle-aged, primarily White, and overweight or obese with a mean BMI of 33.98 (SD = 7.35; median BMI = 32.30). Over 40% reported subjective sleepiness (Epworth Sleepiness Scale (ESS) ≥10) and had OSA (78% with apnea + hypopnea index (AHI) ≥5/hr). Measurements. Evaluation included questionnaires to evaluate subjective sleepiness (Epworth Sleepiness Scale (ESS)) and functional outcomes (Functional Outcomes of Sleep Questionnaire (FOSQ)), an activity monitor, and an overnight sleep study to determine OSA severity. Results. Increased subjective sleepiness was significantly associated with lower scores on the FOSQ but not with average number of steps walked per day. A multiple regression analysis showed that higher AHI values were significantly associated with lower average number of steps walked per day after controlling patient's age, sex, and ESS. Conclusion. Subjective sleepiness was associated with perceived difficulty in activity but not with objectively measured activity. However, OSA severity was associated with decreased objective physical activity in aging adults.
The aim of the present study was to examine the prevalence of metabolic syndrome (MS) and its components among obstructive sleep apnea (OSA) patients vs controls, as well as to investigate which of these components are strongly associated with the presence of OSA in subjects reporting symptoms indicating sleep-disordered breathing. Included were 83 consecutive male subjects, without known concomitant diseases, who visited an outpatient clinic of obesity, diabetes and metabolism. Based on polysomnography, these were divided into two groups: OSA patients (n = 53) and controls (n = 30). Parameters indicating MS, according to the NCEP ATP III criteria (blood pressure, waist circumference, glucose, triglycerides, and HDL-cholesterol levels) were evaluated in both groups. The criteria for MS were fulfilled in 49 participants. Presence of MS was significantly correlated with the presence of OSA. However, after adjustment for BMI, only serum glucose was significantly associated with the presence of OSA (P = 0.002). Conversely, the presence of MS was associated with a significant reduction in percentage of slow-wave sleep (P = 0.030). In conclusion, these results provide further evidence for the association between OSA and MS. Between subjects with MS, elevated serum glucose levels indicate a higher probability for the presence of OSA.
diabetes mellitus; glucose; metabolic syndrome; obstructive sleep apnea
To study the risk for obstructive sleep apnea (OSA) in a group of non-obese and obese PCOS and control women. Women with polycystic ovary syndrome (PCOS) are at high risk for obstructive sleep apnea (OSA). Whether this risk is independent of obesity is not clear.
Design/Patients/Interventions/Main Outcome Measures
In a prospective study, 44 women with PCOS and 34 control women completed the Berlin questionnaire for assessment of OSA risk. All women underwent fasting determination of androgens, glucose and insulin.
Women with PCOS were more obese compared to control women (p=0.02). However, there were no differences in BMI once subjects were divided into non-obese (PCOS n=17 and control n=26) and obese (PCOS n=26 and control n=8) groups. Women with PCOS had higher prevalence of high risk OSA compared to control women on the Berlin questionnaire (47% vs. 15%, P<0.01). However, none of the non-obese PCOS and control women screened positive for high risk OSA. Among the obese group, the risk did not differ between groups (77% vs. 63%, P= 0.65).
Our findings indicate that even though the risk for OSA in PCOS is high, it is related to the high prevalence of severe obesity. The risk for OSA among non-obese women with PCOS is very low. However, our findings are limited by lack of polysomnographic confirmation of OSA.
Berlin questionnaire; Obesity; Insulin resistance; Body mass index
OBJECTIVE—To evaluate the incidence of sleep apnoea in acute and chronic coronary syndromes.
DESIGN—Analysis of sleep and breathing characteristics in a polysomnographic study.
SETTING—Cardiology department in tertiary referral centre.
PATIENTS—23 patients were studied soon after acute myocardial infarction (group 1), 22 after clinical stabilisation of unstable angina (group 2), and 22 who had stable angina (group 3). Conditions liable to cause sleep apnoea, such as obesity, chronic obstructive pulmonary disease, neurological disorders, or the use of benzodiazepines, were exclusion criteria.
MAIN OUTCOME MEASURES—Sleep apnoea and hypopnoea, oxygen saturation, and sleep indices evaluated soon after clinical stabilisation in groups 1 and 2 and also in group 3.
RESULTS—Sleep apnoea, mainly of the central type, was equally present in groups 1 and 2 (mean (SD) apnoea-hypopnoea index: 11.10 (19.42) and 14.79 (20.52), respectively) and more severe than in group 3 (2.82 (6.43), p < 0.01). Total time spent at SaO2 < 90%, although significantly greater in group 1 and 2 (0.89 (2.4), 1.42 (3.23) min) than in group 3 (0.01 (0.05) min, p < 0.05), was clinically irrelevant. More arousals per hour of sleep (p < 0.05) were detected in group 1 (5.15 (3.71)) and group 2 (5.31 (2.14)) than in group 3 (2.83 (1.51)).
CONCLUSIONS—Sleep apnoea, chiefly of the central type, not only characterises acute myocardial infarction, as found by others, but also unstable angina studied after recent stabilisation. Patient selection by exclusion of other causes of breathing disorders shows that coronary disease related apnoea is absent in the chronic coronary syndrome. In acute syndromes the lack of clinically significant apnoea related oxygen desaturation, together with the low associated incidence of major ischaemic and arrhythmic events, suggests that sleep apnoea is benign in these circumstances, despite a worsening of sleep quality.
Keywords: acute myocardial infarction; unstable angina; stable angina; sleep apnoea
Asthma and obstructive sleep apnea (OSA) in children share multiple epidemiological risk factors and the prevalence of snoring is higher in asthmatic children, suggesting that the latter may be at increased risk for OSA. Since both asthma and OSA are inflammatory disorders, we hypothesized that polysomnographically-demonstrated OSA would be more frequent among poorly controlled asthmatics (PCA), and that treatment of OSA, if present, would ameliorate the frequency of acute asthmatic exacerbations (AAE).
Children with PCA were referred for an overnight sleep study, and adenotonsillectomy (T&A) was performed if OSA was present. Frequency of asthma symptoms and exacerbations were compared.
92 PCA children, ages 3-10 years, with a mean frequency of AAE of 3.4±0.4/year were prospectively referred for a sleep study. OSA (i.e., AHI>5/hrTST) was present in 58 patients (63.0%; OR: 40.9, 12.9-144.1, p<0.000001 compared to the prevalence of OSA in a non-asthmatic population). Information at 1-year follow-up was available for 35 PCA children after tonsillectomy and adenoidectomy (T&A). The annual frequency of AAE, rescue inhaled use, and asthma symptoms in this sub-group decreased compared to no changes in the group without OSA.
The prevalence of OSA is markedly increased among PCA children and treatment of OSA appears to be associated with substantial improvements in the severity of the underlying asthmatic condition.
Sleep-disordered breathing (SDB) is a prevalent condition in children and is associated with increased cardiovascular morbidity. Circulating levels of C-reactive protein (CRP), a proinflammatory protein, are associated with increased risk for atherosclerosis. Plasma CRP levels in snoring children have yielded conflicting results, such that it remains unclear whether OSA is mechanistically involved in such elevations of CRP.
Consecutive nonobese children with polysomnographically demonstrated obstructive sleep apnea underwent blood draws in the morning after their corresponding sleep studies on 2 occasions, namely at diagnosis of obstructive sleep apnea and 10 to 14 weeks after adenotonsillectomy. High-sensitivity CRP serum concentrations were determined within 2 to 3 hours after collection, using a particle-enhanced turbidimetric immunoassay technique.
Twenty children with obstructive sleep apnea (mean age 7.3 ± 1.9 years; 55% boys; relative body mass index: 88% ± 12.0%) with a mean apnea-hypopnea index at diagnosis of 15.6 ± 2.9 events per hour of total sleep time and nadir SaO2 of 82.3% ± 2.5% were included. Mean initial CRP levels at obstructive sleep apnea diagnosis were 0.67 ± 0.21 mg/dL and decreased to 0.23 ± 0.07 mg/dL after adenotonsillectomy (p < .05), along with significant decreases in measured apnea-hypopnea index (2.2 ± 0.8 events/h of total sleep time ; p < .01) and improved oxygenation (mean nadir SaO2 values: 88.6% ± 1.9%; p < .01).
Obstructive sleep apnea is frequently associated with increases in CRP levels that are reversible upon treatment. Thus, obstructive sleep apnea induces a systemic inflammatory response in children, which, if left untreated, may potentially lead to cardiovascular morbidity.
C-reactive protein; sleep-disordered breathing; children; inflammation; obstructive sleep apnea
The aim of this study was to investigate optimal continuous positive airway pressure (CPAP) level, to examine the factors affecting optimal CPAP level, and to develop a predictive equation for optimal CPAP level in Korean patients with obstructive sleep apnea syndrome (OSAS).
A total of 202 patients with OSAS who underwent successful manual titration for CPAP treatment were included in this study. Correlations between the optimal CPAP level and baseline data including anthropometric and polysomnographic variables were analyzed. A predictive equation for optimal CPAP level was developed based on anthropometric and polysomonographic data.
The mean optimal CPAP level in 202 patients with OSAS was 7.8±2.3 cm H2O. The mean optimal CPAP level in the mild, moderate, and severe OSAS groups was 6.0±1.3, 7.4±1.9, and 9.1±2.1 cm H2O, respectively. The apneahypopnea index (AHI) (r=0.595, P<0.001), arousal index (r=0.542, P<0.001), minimal SaO2 (r=-0.502, P<0.001), body mass index (BMI) (r=0.494, P<0.001), neck circumference (r=0.265, P<0.001), and age (r=-0.164, P=0.019) were significantly correlated with optimal CPAP level. The best predictive equation according to stepwise multiple linear regression analysis was: Optimal CPAP level (cm H2O)=0.681+(0.205×BMI)+(0.040×AHI). Forty-two percent of the variance in the optimal CPAP level was explained by this equation (R2=0.42, P<0.001).
A predictive equation for optimal CPAP level in Korean patients with OSAS was developed using AHI and BMI, which can be easily measured during the diagnostic process.
Obstructive sleep apnea syndrome; Continuous positive airway pressure; Polysomnography; Body mass index