Predictors Of Sleep-disordered Breathing Research Articles

Prevalence and Predictors of Sleep-Disordered Breathing in Men Participating in the Multicenter AIDS Cohort Study

Data on the prevalence of sleep-disordered breathing (SDB) in people with HIV are limited. Moreover, whether the associations between SDB and age or BMI differ by HIV status is unknown. Is SDB more prevalent in men with HIV than those without HIV, and do the predictors of SDB differ between the two groups? Home polysomnography was used in the Multicenter AIDS Cohort Study to assess SDB prevalence in men with (n= 466; 92%virologically suppressed) and without (n= 370) HIV. SDB was defined using the oxygen desaturation index (ODI) and the apnea-hypopnea index (AHI), using four definitions:≥ 5 events/h based on an ODI with a 3%(ODI3) or 4%(ODI4) oxygen desaturation, or an AHI with a 3%oxygen desaturation or EEG arousal (AHI3a) or with a 4%oxygen desaturation (AHI4). SDB prevalence was similar in men with and without HIV using the ODI3 and AHI3a definitions. However, SDB prevalence was higher in men with than without HIV using the ODI4 (55.9%vs47.8%; P= .04) and the AHI4 definitions (57.9%vs50.4%; P= .06). Mild and moderate SDB were more common in men with than without HIV. Associations between SDB prevalence and age, race, and BMI were similar in men with and without HIV. Among men with HIV, viral load, CD4 cell count, and use of antiretroviral medications were not associated with SDB prevalence. SDB prevalence was high overall but greater in men with than without HIV using the ODI4 threshold definition. Efforts to diagnose SDB are warranted in people with HIV, given that SDB is associated with daytime sleepiness and impaired quality of life.

Prevalence, clinical characteristics, and predictors of sleep disordered breathing in hospitalized heart failure patients.

Heart failure (HF) is often comorbid with sleep disordered breathing (SDB). This prospective study investigated the prevalence, clinical characteristics, and predictors of SDB in hospitalized HF patients. Sleep studies were performed on hospitalized HF patients from January 2015 to February 2019. SDB was categorized as no/mild SDB, obstructive sleep apnea (OSA), and central sleep apnea (CSA). The study included 1069 hospitalized HF patients. The prevalence rates of OSA and CSA were 16.6% and 36.9%, respectively. Patients with OSA or CSA were more likely to be male and have a higher body mass index (BMI) and more comorbidities. Multivariate logistic regression analysis showed that male sex (odds ratio [OR] = 1.803, 95% confidence interval [CI] = 1.099-2.958), BMI (per 5 kg/m2 increase: OR = 2.270, 95% CI = 1.852-2.783), hypertension (OR = 2.719, 95% CI = 1.817-4.070), diabetes (OR = 1.477, 95% CI = 1.020-2.139), and left ventricular ejection fraction (LVEF) (per 5% increase, OR = 1.126, 95% CI = 1.053-1.204) were independent predictors of OSA. Male sex (OR = 1.699, 95% CI = 1.085-1.271), age (per 10 years, OR = 1.235, 95% CI = 1.118-1.363), heart rate (per 10 bpm, OR = 1.174, 95% CI = 1.099-2.958), LVEF (per 5% increase, OR = 0.882, 95% CI = 0.835-0.932), NT-proBNP (lnNT-proBNP, OR = 1.234, 95% CI = 1.089-1.398) and hypocapnia (OR = 1.455, 95% CI = 1.105-1.915) were independent predictors of CSA. The areas under the receiver operating characteristic curves were 0.794 (95% CI = 0.758-0.830) and 0.673 (95% CI = 0.640-0.706), respectively. More than half of hospitalized HF patients had OSA or CSA, and CSA was the predominant type. OSA and CSA predictors differ. The clinical characteristics of HF patients can help make preliminary predictions for SDB patients.

Prevalence and predictors of sleep-disordered breathing in chronic heart failure: the SchlaHF-XT registry.

Heart failure with preserved ejection fraction (HFpEF) is a condition with increasing prevalence. Sleep-disordered breathing (SDB) is an important co-morbidity in HFpEF. The SchlaHF-XT registry evaluated the sex-specific prevalence and predictors of SDB, including obstructive (OSA) and central sleep apnoea, in patients with HFpEF compared with heart failure with mildly reduced (HFmrEF) or reduced (HFrEF) ejection fraction. Consecutive adults with chronic heart failure treated according to current guidelines were enrolled. The presence of moderate-to-severe SDB (apnoea-hypopnoea index ≥15/h) was determined using Type 3 polygraphic devices. Of 3289 patients included, 2032 had HFpEF, 559 had HFmrEF, and 698 had HFrEF, of whom 34, 21, 23, and 42%, respectively, were female. Prevalence of SDB in HFpEF was high, but significantly lower than in HFmrEF or HFrEF (36% vs. 41 and 48%, respectively). Rates of SDB in males and females were 41 and 28% in HFpEF, 44 and 30% in HFmrEF, and 50 and 40% in HFrEF. The proportion of males and females with SDB who had OSA was significantly greater in those with HFpEF vs. HFrEF. Male sex, older age, higher body mass index, and New York Heart Association functional Class III/IV were significant predictors of moderate-to-severe SDB in HFpEF patients. Prevalence of SDB in HFpEF was high, but lower than in patients with HFmrEF or HFrEF. Moderate-to-severe SDB occurred more frequently in males than in females across the whole spectrum of heart failure. In both sexes, the proportion of OSA in SDB patients with HFpEF was higher than in those with HFrEF.

Abstract MP26: Visceral Obesity and Systemic Inflammation Predict Sleep Disordered Breathing in Normal Weight, Never Obese Adolescents: A Longitudinal, Population-Based Study

Introduction: Although obesity is a known risk factor for sleep disordered breathing (SDB), a significant proportion of children with SDB are not obese or overweight as per body mass index percentile (BMI%) for age-and-sex. It is unknown whether premorbid or concurrent adiposity phenotypes are associated with SDB in normal weight youth. Hypothesis: We hypothesize that central obesity is a predictor of apnea/hypopnea index (AHI) in adolescents who have been otherwise normal weight since childhood. Methods: We analyzed data from the Penn State Child Cohort (N=421), a random population-based sample of 8.7 (1.7) year old children followed-up as 17.0 (2.3) year old adolescents. Of these, 242 subjects (49.2% female, 18.2% minority) were classified as persistently normal weight based on BMI%<85 at both baseline and follow-up. Neck, hip and waist circumference (WC) were measured and “central obesity” was defined as a WC%≥85 for age-and-sex at baseline. During the follow-up exam, android and gynoid distribution and subcutaneous (SAT) and visceral (VAT) adipose tissue composition were assessed via DEXA scan, while inflammatory biomarkers were assayed from a fasting blood sample. The AHI was obtained from 9-hour, in-lab polysomnography at baseline and follow-up. Multivariable linear regression models examined the association between adiposity and inflammation with AHI at follow-up while adjusting for sex, race, adenotonsillectomy, age and AHI at baseline. Results: The average AHI at baseline was 0.7 (0.9) events/hour and 2.3 (6.3) events/hour at follow-up. Unadjusted analyses showed that WC (β=0.159) and central obesity (β=0.227) at baseline, but not BMI%, neck or hip circumference, and VAT (β=0.307), IL-6 (β=0.245), SAT (β=0.235), CRP (β=0.222), and android distribution (β=0.195) at follow-up were significantly (P<0.05) associated with a higher follow-up AHI. Multivariable-adjusted analyses showed that VAT (β=0.299), IL-6 (β=0.191), central obesity (β=0.185) and CRP (β=0.163) were independently associated with a higher follow-up AHI. Conclusions: This is the first study to demonstrate that central obesity in childhood is a strong predictor of SDB in adolescence, even in individuals who have been persistently normal weight since childhood as per BMI% standards. These data support the clinical utility of simple measures of central obesity in childhood (i.e., WC) as early surrogate markers of increased risk of future development of SDB in the transition to adolescence. Furthermore, our study demonstrates that increased visceral adiposity and systemic inflammation are strong correlates of adolescent SDB, which supports the clinical utility of these biomarkers in predicting the cardiometabolic risk associated with adolescent SDB.

Predictors of Sleep-disordered Breathing in Pregnancy

(Am J Obstet Gynecol. 2018;218:521.e1–e12) Sleep-disordered breathing (SDB) in pregnancy is associated with an increased risk of complications and adverse outcomes, including preeclampsia, venous thromboembolism, severe maternal morbidity, preterm delivery, and maternal death. Identifying women with SDB is difficult, however, as SDB symptoms are not very specific. The best method for diagnosis of SDB is overnight polysomnography, which is expensive and inconvenient. This study used a large cohort of pregnant women to establish clinically feasible prediction models for SDB.

High Negative Predictive Value of Normal Body Mass Index for Obstructive Sleep Apnea in the Lateral Sleeping Position.

Obesity is a major risk factor for obstructive sleep apnea (OSA). Patients who are not obese and who have OSA usually present with a low apnea-hypopnea index (AHI) in the lateral sleeping position. Hence, sleep-disordered breathing (SDB) seems more dependent on body mass index (BMI) in the lateral sleeping position than the supine sleep position. This makes obesity a better predictor of SDB in the lateral sleeping position. The objective of this study was to find a negative predictive value of normal BMI for SDB in relation to sleep positions, thus defining a group of patients who could be treated by positional intervention, and prioritizing the use of polysomnography diagnostics. This study comprises a retrospective and prospective part run on groups of 1,181 and 821 consecutive patients, respectively. All had been referred to the university-based sleep laboratory because of suspected OSA and underwent polysomnography. In the retrospective study, areas under the receiver operating characteristic curves for normal BMI at AHI ≥ 5 and AHI ≥ 15 events/h were found to be larger in the lateral sleeping positing than supine: 0.79 versus 0.69 and 0.80 versus 0.68, respectively (P < .05). Comparable results were obtained in the prospective study. For normal BMI, the negative predictive value for AHI < 15 events/h in the lateral sleep position was 97.5% and 97.1% in the retrospective and prospective study, respectively. Normal BMI offers a high negative predictive value for moderate or severe OSA in the lateral sleeping position.

Predictors of sleep-disordered breathing in pregnancy

Sleep-disordered breathing (SDB) is common in pregnancy, but there are limited data on predictors. The objective of this study was to develop predictive models of sleep-disordered breathing during pregnancy. Nulliparous women completed validated questionnaires to assess for symptoms related to snoring, fatigue, excessive daytime sleepiness, insomnia, and restless leg syndrome. The questionnaires included questions regarding the timing of sleep and sleep duration, work schedules (eg, shift work, night work), sleep positions, and previously diagnosed sleep disorders. Frequent snoring was defined as self-reported snoring ≥3 days per week. Participants underwent in-home portable sleep studies for sleep-disordered breathing assessment in early (6-15 weeks gestation) and mid pregnancy (22-31 weeks gestation). Sleep-disordered breathing was characterized by an apnea hypopnea index that included all apneas, plus hypopneas with ≥3% oxygen desaturation. For primary analyses, an apnea hypopnea index ≥5 events per hour was used to define sleep-disordered breathing. Odds ratios and 95% confidence intervals were calculated for predictor variables. Predictive ability of the logistic models was estimated with area under the receiver-operating-characteristic curves, along with sensitivities, specificities, and positive and negative predictive values and likelihood ratios. Among 3705 women who were enrolled, data were available for 3264 and 2512 women in early and mid pregnancy, respectively. The corresponding prevalence of sleep-disordered breathing was 3.6% and 8.3%, respectively. At each time point in gestation, frequent snoring, chronic hypertension, greater maternal age, body mass index, neck circumference, and systolic blood pressure were associated most strongly with an increased risk of sleep-disordered breathing. Logistic regression models that included current age, body mass index, and frequent snoring predicted sleep-disordered breathing in early pregnancy, sleep-disordered breathing in mid pregnancy, and new onset sleep-disordered breathing in mid pregnancy with 10-fold cross-validated area under the receiver-operating-characteristic curves of 0.870, 0.838, and 0.809. We provide a supplement with expanded tables, integrated predictiveness, classification curves, and an predicted probability calculator. Among nulliparous pregnant women, logistic regression models with just 3 variables (ie, age, body mass index, and frequent snoring) achieved good prediction of prevalent and incident sleep-disordered breathing. These results can help with screening for sleep-disordered breathing in the clinical setting and for future clinical treatment trials.

Prevalence and risk factors for sleep-disordered breathing in chilean schoolchildren

To describe the prevalence of sleep-disordered breathing (SDB) in Chilean schoolchil dren and study associated risk factors. We carried out a transversal and des criptive study. Questionnaires were sent to the parents of children attending first year of elementary school in the Metropolitan Region (Santiago), the Biobío Region (Concepción, Chillán, Yumbel) and the Magallanes Region (Porvenir and Puerto Natales). Anthropometric data, school performan ce, household characteristics, indoor pollutants, medical history, and current symptoms of asthma, allergic rhinitis, and atopic dermatitis were recorded. The nutritional status was determined accor ding to z-BMI. A pediatric sleep questionnaire validated in Spanish (PSQ) was applied. 564 questionnaires were analyzed, the median age was six years (range 5 to 9), 44.9% male. The SDB prevalence was 17.7% (n = 100): 6% in Vitacura (Metropolitan Region), 28.7% in Chillán (Biobío Region), and 36.4% in Puerto Natales (Magallanes Region) (p = 0.001). The group with SDB had a higher proportion of men (54.5 vs 42.8%, p = 0.033), lower academic performance (overall grade point average 6.36 ± 0.48 vs 6.56 ± 0.34, p = 0.001), lower maternal higher education (44.4% vs 69.9%, p = 0.001), and higher exposure to indoor pollutants than those without SDB. After the multivariate analysis, symptoms of rhinitis in the last 12 months (OR 4.79, 95% CI 2.20-10.43) and lower maternal educational level (OR 3.51; 95% CI 1.53-8.02) remained as predictors of SDB. Con clusions: Chilean schoolchildren have a high prevalence of SDB with demographic differences. It was associated with social risk factors, more specific factors of lung damage, and worse sleep quality and quantity.

Predictor factors of sleep-disordered breathing in heart failure

BackgroundHeart failure (HF) is characterized by its high mortality, frequent hospitalizations, and reduced quality of life. Sleep-disordered breathing (SDB), one of the common comorbidities, accelerates the progression of HF.ObjectivesThe objectives of the study were (a) to investigate the prevalence and type of SDB in HF patients and (b) to determine the predictors of SDB.Materials and methodsIn a cross-sectional analytic study, all eligible patients of Assiut Chest and Cardiology Department admitted (100 patients) during the period from August 2015 to March 2016 were included in this study. Clinical assessment, full-night attended polysomnography, and echocardiography were recorded and compared between patients with (SDB) (85 patients) and those without SDB (15 patients).ResultsSDB was found in 85% of patients [53% had obstructive sleep apnea (OSA) and 32% had central sleep apnea (CSA)]. OSA patients are characterized by higher BMI and neck and waist circumference. There was a higher prevalence of hypertension, as well as mean blood pressure, systolic blood pressure, diastolic blood pressure, in OSA patients. Loud snoring was the only clinical symptom associated with OSA as compared with CSA. CSA patients had a significant reduction in PaCO2. OSA patients showed a significant increase in desaturation index and time spent with oxygen saturation less than 90%. Maximum heart rate and brady/tachy index were significantly increased in OSA. Cycle length was significantly increased in CSA.ConclusionThe prevalence of sleep apnea was high in patients with stable HF (85%). OSA was the predominant type (53%). The predictors of SDB were BMI (≥30), systemic hypertension, neck circumference more than 40 cm, waist circumference more than 110 cm, and ejection fraction (left ventricular ejection fraction) (≤45%).

Sleep-disordered Breathing in Cardiac Rehabilitation: Prevalence, Predictors, and Influence on the Six-Minute Walk Test

Identification of non-traditional risk factors is an important component of cardiac rehabilitation (CR). However, the prevalence and predictors of sleep-disordered breathing (SDB) and its influence on exercise performance in patients attending CR remain poorly described. Patients enrolled in a national CR centre were eligible for a comprehensive SDB screening program. Screening questionnaires for SDB, overnight sleep study, and the 6-minute walk test (6MWT) were conducted. We recruited 332 patients (mean age 62±10 years, 62.4% male) attending CR for primary (29.2%) or secondary (70.8%) prevention, of which 209 successfully completed the overnight sleep study. Sleep-disordered breathing group patients (n=68, 32.5%) were older and had a higher body mass index (BMI) and neck and waist circumferences than the non-SDB group patients. After adjusting for neck and waist circumference, age (OR=1.06; 95% CI 1.02-1.10; p=0.001) and BMI (OR=1.19; 95% CI 1.10-1.30; p<0.001) remained independent predictors of SDB. A high risk of SDB based on the Berlin Questionnaire (43.4% versus 35.5%, p=0.277) or STOP-BANG questionnaire (63.2% versus 53.2%, p=0.170) and excessive daytime sleepiness (Epworth Sleepiness Scale >10, 23.9% versus 17.7%, p=0.297) were similar between the groups. The 6MWT scores were significantly lower in the SDB than non-SDB group (mean difference -32 m; 95% CI -57-7; p=0.013). The relationship was no longer significant after adjusting for age, sex, and waist circumference. Sleep-disordered breathing is prevalent in CR patients and is independently predicted by ageing and obesity. The association between SDB and poorer exercise performance may be explained by age, sex, and waist circumference.

Predictors of Sleep-Disordered Breathing in Lung Transplant Recipients

Predictors of Sleep-Disordered Breathing in Lung Transplant Recipients

Predictors of sleep-disordered breathing in obese adults who are chronic short sleepers.

Sleep disordered breathing (SDB) is common in obese adults, but not all obese adults have SDB. The aim of these analyses was to determine what predicted SDB in a sample of obese adults. We conducted cross-sectional analysis of 139 obese men and women aged 18-50 years who are chronic short sleepers. Habitual sleep duration and sleep efficiency were estimated using two weeks of wrist actigraphy. Respiratory disturbance index (RDI) was assessed by a portable screening device. SDB was defined as RDI ≥15 events h(-1). Subjective sleep quality, sleepiness, and sociodemographic characteristics were evaluated by questionnaires. Increased sleep duration from actigraphy was associated with reduced odds of SDB (OR 0.44 per hour, p=0.043). Neither subjective sleep quality nor sleepiness was associated with SDB. Male sex, older age, and increased waist circumference were associated with increased odds of SDB. In this sample of obese adults, subjective measures of sleep quality and sleepiness were not indicators of SDB. These results suggest that, in obese patients, physicians should not rely on subjective measures to determine who should be referred for a clinical sleep study. A wider use of portable apnea screening devices should be considered in nonsymptomatic, non-Hispanic white males.

Natural History of Sleep-Disordered Breathing: Shedding Light on the Early Years

Natural History of Sleep-Disordered Breathing: Shedding Light on the Early Years

Sleep-Disordered Breathing and Blood Pressure in Children

HomeHypertensionVol. 52, No. 5Sleep-Disordered Breathing and Blood Pressure in Children Free AccessEditorialPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessEditorialPDF/EPUBSleep-Disordered Breathing and Blood Pressure in Children Brent M. Egan Brent M. EganBrent M. Egan From the Department of Medicine, Medical University of South Carolina, Charleston. Search for more papers by this author Originally published6 Oct 2008https://doi.org/10.1161/HYPERTENSIONAHA.108.118083Hypertension. 2008;52:807Other version(s) of this articleYou are viewing the most recent version of this article. Previous versions: October 6, 2008: Previous Version 1 The article by Bixler et al in this edition of Hypertension1 adds to a growing body of evidence that risk factors associated with abdominal obesity in adults, namely, sleep-disordered breathing (apnea-hypopnea), occur in children as well. Specifically, sleep-disordered breathing appeared to be more strongly associated with waist circumference, a surrogate marker for abdominal obesity, than with body mass index, a more generalized or global obesity marker. Although body mass index in children and youth is strongly related to prevalent metabolic syndrome,2 other data show that waist circumference is as good as,3 if not better than,4 body mass index as a predictive factor for metabolic syndrome at early ages. In adults, prevalent and incident sleep-disordered breathing are associated with body mass index.5,6On a positive note, the prevalence of moderate sleep-disordered breathing in children, which was associated with a major effect on systolic blood pressure of >10 mm Hg, is relatively uncommon at ≈1%. Although mild sleep-disordered breathing was identified in 25% of children, the systolic blood pressure effect was a more modest ≈2 mm Hg. Despite the lesser current blood pressure concern for the 25% of children with mild sleep-disordered breathing, evidence from the Bogalusa Heart Study indicates that children with greater levels of blood pressure and other metabolic syndrome risk factors also have a steeper trajectory of increasing risk factor values over time than children with lesser risk.7 Thus, future studies in children to examine changes in the apnea-hypopnea index, as well as metabolic syndrome risk factors over time, would be of interest.Also of note in the report by Bixler et al1 is the observation that snoring and sleep-disordered breathing were related to blood pressure independent of age and waist circumference in multivariate regression modeling. In adults, sleep-disordered breathing is associated with hypertension independently of both body mass index and waist:hip ratio.8 In this regard, it should be noted that waist circumference but not body mass index was included in the multivariate regression in Table 4 of the report. Thus, it is not clear whether the association of sleep-disordered breathing with blood pressure in children is independent of both waist circumference and body mass index. Even without further studies, the current report adds to the weight of evidence that health risks associated with abdominal obesity begin early in life, and primary prevention should begin even earlier.The opinions expressed in this editorial are not necessarily those of the editors or of the American Heart Association.DisclosuresNone.FootnotesCorrespondence to Brent M. Egan, Medical University of South Carolina, 135 Rutledge Ave, RT 1230, Charleston, SC 29425. E-mail [email protected] References 1 Bixler EO, Vgontzas AN, Lin H-M, Liao D, Calhoun S, Fedok F, Vlasic V, Graff G. Blood pressure associated with sleep-disordered breathing in a population sample of children. Hypertension. 2008; 52: 841–846.LinkGoogle Scholar2 Weiss R, Dziura J, Burgert TS, Tamborlane WV, Taksali SE, Yeckel CW, Allen K, Lopes M, Sayoe M, Morrison J, Sherwin RS, Caprio S. Obesity and the metabolic syndrome in children and adolescents. N Engl J Med. 2004; 350: 2362–2374.CrossrefMedlineGoogle Scholar3 Katzmarzyk PT, Srinivasan SR, Chen W, Malina RM, Bouchard C, Berenson GS. Body mass index, waist circumference, and clustering of cardiovascular disease risk factors in a biracial sample of children and adolescents. Pediatrics. 2004; 114: e198–e205.CrossrefMedlineGoogle Scholar4 Moreno LA, Pineda I, Rodriguez G, Fleta J, Sarria A, Bueno M. Waist circumference for the screening of metabolic syndrome in children. Acta Paediat. 2002; 91: 1307–1312.CrossrefMedlineGoogle Scholar5 Young T, Shahar E, Nieto FJ, Redline S, Newman AB, Gottlieb DJk, Walsleben JA, Finn L, Enright P, Samet JM. Predictors of sleep-disordered breathing in community-dwelling adults. Arch Intern Med. 2002; 162: 893–900.CrossrefMedlineGoogle Scholar6 Tishler PV, Larkin EK, Schluchter MD, Redline S. Incidence of sleep-disordered breathing in an urban adult population. JAMA. 2003; 289: 2230–2237.CrossrefMedlineGoogle Scholar7 Srinivasan SR, Myers L, Berenson GS. Changes in metabolic syndrome variables since childhood in prehypertensive and hypertensive subjects: the Bogalusa Heart Study. Hypertension. 2006; 48: 33–39.LinkGoogle Scholar8 Nieto FJ, Young TB, Lilnd BK, Shahar E, Samet JM, Redline S, D'Agostino RB, Newman AB, Lebowitz MD, Pickering TG. Association of sleep-disordered breathing, sleep apnea, and hypertension in a large community-based study. JAMA. 2000; 283: 1829–1836.CrossrefMedlineGoogle Scholar Previous Back to top Next FiguresReferencesRelatedDetails November 2008Vol 52, Issue 5 Advertisement Article InformationMetrics https://doi.org/10.1161/HYPERTENSIONAHA.108.118083PMID: 18838622 Originally publishedOctober 6, 2008 PDF download Advertisement SubjectsEpidemiologyObesity

Sleep‐disordered breathing in a middle‐aged and older Polish urban population

Obstructive sleep apnoea syndrome (OSAS) is a frequent disorder; however, the prevalence of sleep-disordered breathing is not well known in many countries. The aim of our investigation was to assess the prevalence of sleep-disordered breathing (SDB) in a representative sample of the population of Warsaw. We studied 676 subjects (57.1% of the randomised cohort from the Monica II study). The sample comprised 356 males (52.7%) and 320 females (47.3%), whose mean age was 56.6 +/- 8.2 years (range 41-72 years). Mean number of apnoeas and hypopnoeas per hour of time in bed (AH) in males was 7 +/- 9.5 and in females 3.9 +/- 6.6 (P < 0.001). SDB (cut-off point AH > 5 or >10) was identified in 188 subjects (27.8%) and 97 subjects (14.3%), respectively. SDB was established twice as frequently in males as in females (respectively 36.5 versus 18.5%; P < 0.001 for AH > 5 and 19.8 versus 8.5%; P < 0.001 for AH > 10). A diagnosis of OSAS AH > 10 and Epworth Sleepiness Score > or =11 points was established in 51 subjects (7.5%). The prevalence of OSAS was nearly four times higher in males (40 subjects, 11.2%) than in females (11 subjects, 3.4%; P < 0.001). The severity of OSAS was similar in both sexes (AH: males 32.3 +/- 14.9 and females 31.4.1 +/- 15.4). Older age and male sex were predictors of SDB. SDB and OSAS were independent predictors of coronary artery disease after adjusting for age, sex, body mass index, neck circumference and smoking habit.

Predictors of sleep-disordered breathing in community-dwelling adults: the Sleep Heart Health Study.

Sleep-disordered breathing (SDB) is common, but largely undiagnosed in the general population. Information on demographic patterns of SDB occurrence and its predictive factors in the general population is needed to target high-risk groups that may benefit from diagnosis. The sample comprised 5615 community-dwelling men and women aged between 40 and 98 years who were enrolled in the Sleep Heart Health Study. Data were collected by questionnaire, clinical examinations, and in-home polysomnography. Sleep-disordered breathing status was based on the average number of apnea and hypopnea episodes per hour of sleep (apnea-hypopnea index [AHI]). We used multiple logistic regression modeling to estimate cross-sectional associations of selected participant characteristics with SDB defined by an AHI of 15 or greater. Male sex, age, body mass index, neck girth, snoring, and repeated breathing pause frequency were independent, significant correlates of an AHI of 15 or greater. People reporting habitual snoring, loud snoring, and frequent breathing pauses were 3 to 4 times more likely to have an AHI of 15 or greater vs an AHI less than 15, but there were weaker associations for other factors with an AHI of 15 or greater. The odds ratios (95% confidence interval) for an AHI of 15 or greater vs an AHI less than 15 were 1.6 and 1.5, respectively, for 1-SD increments in body mass index and neck girth. As age increased, the magnitude of associations for SDB and body habitus, snoring, and breathing pauses decreased. A significant proportion of occult SDB in the general population would be missed if screening or case finding were based solely on increased body habitus or male sex. Breathing pauses and obesity may be particularly insensitive for identifying SDB in older people. A better understanding of predictive factors for SDB, particularly in older adults, is needed.

A Community Study of Sleep-Disordered Breathing in Middle-aged Chinese Men in Hong Kong

Sleep-disordered breathing (SDB) in Asian populations is being increasingly recognized. This study investigated the prevalence of SDB in Chinese middle-aged office-based male workers in Hong Kong. Sleep questionnaires were distributed to 1,542 men (age range, 30 to 60 years), and 784 questionnaires were returned. Subsequently, full polysomnographic (PSG) examinations were conducted in 153 questionnaire respondents. Subjects with an apnea-hypopnea index (AHI) > or =5 were recalled for clinical assessment. Questionnaire respondents were similar in age and body mass index (BMI) to the general community in the target age range and gender. Habitual snoring was reported by 23% of this cohort and was associated with excessive daytime sleepiness (EDS), hypertension, witnessed abnormal breathing pattern, BMI, and leg movements during sleep. Allowing for subject bias in undergoing PSG, the estimated prevalence of SDB and obstructive sleep apnea syndrome (OSAS) (defined as SDB in the presence of EDS) at various AHI cutoff threshold values was 8.8% and 4.1% (AHI > or =5), 6.3% and 3.2% (AHI > or =10), and 5.3% and 3.1% (AHI > or =15). Multiple stepwise logistic regression analysis identified BMI, habitual snoring, time taken to fall asleep, and age as predictors of SDB at AHI > or =5. Analysis of anthropometric parameters indicated that the relative risk of OSAS attributable to obesity was less than in white subjects. This community-based study of sleep apnea among middle-aged men in Hong Kong using full PSG demonstrated an estimated prevalence of OSAS (AHI > or =5 and EDS) at 4.1%. Increasing BMI and age were associated with SDB, although factors other than adiposity may also have an important pathogenic role in OSA in Chinese subjects.

Sleep Apnea in Moderate-Severe Obese Patients.

Obesity induces multiple physiologic changes at the respiratory and circulatory systems level. A study was developed to identify symptoms and signs able to discriminate subjects at high risk of obstructive sleep apnea (OSA) and to evaluate the presence of OSA in a population of obese patients referred to the Clinical Nutrition Service of the Luigi Sacco Hospital for weight loss therapy. Twenty-seven obese patients (14 males, 13 females) without neurologic, cardiac, and lung diseases were measured for height, weight, neck, waist, and hip circumference; a sample of venous blood was taken for hematological data; and were given a pulmonary function test, hemogasanalysis, and full-night polysomnography. Statistical analysis were performed using paired and unpaired StudentOs t test, PearsonOs chi square, and Spearmann Rank correlation; the significance level was set at p<0.05. The results showed hemotological values in the normal range and pulmonary function findings were not different from predicted, but expiratory reserve volume (ERV), as expected in obese subjects, was significantly reduced (p<0.001). Waist, hip, and neck circumference, and waist/hip ratio were 114 +/-14, 118 +/-12, 44 +/-4, and 0.96 +/-0.4 cm respectively. An apnea-hypopnea index (AHI) cutoff value of <15 was used to classify the patients as suffering from OSA: 15 patients (12 males, 3 females, age in years 55 +/-12, body mass index (BMI) kg/m(2) 37 +/-6, AHI 30 +/-12) were OSA and 12 patients were non OSA (2 males, 10 females, age in years 49 +/-20, BMI kg/m(2) 35 +/-2, AHI 3 +/-2). PaO2 and pH were lower and PaCO2 higher in OSA (p<0.05, p<0.01, p<0.05, respectively). Red blood cells (RBC), Hb, and neck circumference were increased in OSA (p<0.05). In OSA patients, S3%, S4% of total sleep time, SaO2% mean of nadir were reduced (p<0.001), and DEF increased (p<0.0001). In obese patients, AHI was correlated with neck circumference (r = 0.74, p<0.0001) and waist/hip ratio (r = 0.48. p<0.01). DEF was correlated with RBC, Hb, Htc% (r = 0.82, 0.71, 0.66, p<0.001). SaO2;% mean of nadir was significantly related to RBC, Hb, and Htc% (r = 0.44, 0.40, p<0.05, respectively). Our data showed a prevalence of OSA in 55% of the obese patients. A significant correlation exists between RBC, Hb, Htc%, with desaturation events frequency (DEF) and SaO2% of nadir indicating that transient, episodic desaturation during sleep is linked to a moderate increase of RBC and Hb found in obese patients with OSA, in contrast to obese, nonOSA patients. The most important result of the present study was the determination that classical symptoms and signs of OSA, such as male gender, neck circumference, waist/hip ratio, RBC, and Hb at the upper limit of normal, are simple inexpensive screening tools, and useful predictors of sleep-disordered breathing and discriminate the individuals with higher risk of OSA.

Sleep and neuromuscular disease: frequency of sleep-disordered breathing in a neuromuscular disease clinic population.

We investigated 60 adult and pediatric patients (33 male, 27 female) with various neuromuscular disorders for sleep-disordered breathing in a clinic population at a local altitude of 1,500 m. Measurements included a questionnaire concerning symptoms of sleep and daytime function, a disability index, and pulmonary function tests. We used an EdenTrace monitor for 1 night to evaluate breathing during sleep and calculated mean and minimum oxygen saturation (SpO2), total apneas, hypopneas, and respiratory disturbance index (RDI). We had validated the EdenTrace II monitor prior to the study. The majority of the patients had symptoms of daytime dysfunction. The frequency of sleep-disordered breathing in this population was much higher (42% with RDI > 15) than frequencies indicated in recent population-based surveys. Spirometry revealed no positional effect in this population. Statistical analysis comparing RDI with disability index, pulmonary function tests, age, sex, body mass index, and Epworth Sleepiness Scales identified no strong correlates that could be used as predictors of sleep-disordered breathing in this population. Sleep studies using ambulatory equipment such as the EdenTrace II are an easy and effective means of identifying sleep-disordered breathing in patients with neuromuscular disorders and, given the high frequency of sleep-disordered breathing in our sample, should be performed on most patients with neuromuscular disorders if sleep-disordered breathing is to be identified early.

Sleep-Disordered Breathing in Community-Dwelling Elderly

These are the final results of a survey of sleep-disordered breathing, which examined objective and subjective information from a large randomly selected elderly sample. We randomly selected 427 elderly people aged 65 yr and over in the city of San Diego, California. Twenty-four percent had an apnea index, AI, greater than or equal to 5 and 62% had a respiratory disturbance index, RDI, greater than or equal to 10. Correlates of sleep-disordered breathing included high relative weight and reports of snoring, breathing cessation at night, nocturnal wandering or confusion, daytime sleepiness and depression. Body mass index, falling asleep at inappropriate times, male gender, no alcohol within 2 hr of bedtime and napping were the best predictors of sleep-disordered breathing. Despite statistical significance, all of the associations between interview variables and apnea indices were small. No combination of demographic variables and symptoms allowed highly reliable prediction of AI or RDI.