Diagnosis of sleep-disordered breathing in patients with chronic heart failure: evaluation of a portable limited sleep study system

Sleep-disordered breathing (SDB) is common in chronic heart failure (CHF), affects disease progression and presents a potential therapeutic target. This study was designed to test the hypothesis that there would be good agreement in diagnostic outcome between home limited sleep studies and in-laboratory polysomnography (PSG) in the identification of SDB in patients with CHF. We performed synchronous in-laboratory Embletta and PSG, and home Embletta studies, prospectively in 20 consecutive patients with stable symptomatic CHF (ejection fraction 33 +/- 12%) on optimal medical therapy. Sleep efficiency was poor at 57 +/- 21%. Unlike synchronous in-laboratory Embletta (kappa coefficient 0.63, P < 0.01), home Embletta showed poor agreement with PSG (kappa coefficient 0.27, P = 0.06). Positive and negative predictive values for home Embletta in detecting SDB were 83% and 57% respectively. In this relatively small study, agreement in diagnostic outcome between home Embletta and PSG, and negative predictive value for the home Embletta, were poor. We explore possible explanations for this, both technical and situational, which should be taken into consideration when considering potential screening or diagnostic tools for SDB in patients with CHF.     

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.     

Sleep-disordered breathing and cardio- and cerebrovascular diseases: 2003 update of clinical significance and future perspectives

Summary The purpose of this review is to summarize current knowledge about the link between sleep-disordered breathing (SDB) and cardiovascular and cerebrovascular diseases. Obstructive sleep apnoea (OSA) is a well-established risk factor for systemic arterial hypertension, and its treatment with continuous positive airway pressure leads to a decrease in daytime and night-time blood pressure profiles. Pulmonary arterial hypertension occurs in 20–30% of OSA patients and is usually mild. It is not yet clear if OSA per se leads to pulmonary hypertension or if the coexistence of chronic obstructive pulmonary disease with daytime and/or sleep-related hypoxaemia is required to provoke a persistent rise in pulmonary artery pressure. Furthermore, OSA is associated with nocturnal cardiac arrhythmias, especially cyclical fluctuations of the heart rate in response to recurrent apnoeas. Atrioventricular conduction blocks and ventricular premature beats are less often observed and seem to be confined to patients with severe OSA and those with accompanying ischaemic heart disease. The association between OSA and vaso-occlusive disease (i.e. atherosclerosis) is less clear. However, accumulating experimental and epidemiological data support such a link. Thus, OSA may lead to coronary artery disease (CAD) and stroke by promoting atherosclerosis. Correspondingly, patients with CAD or acute stroke show a high prevalence of SDB. Cheyne–Stokes respiration (CSR) is a specific pattern of central sleep apnoea occurring in patients with advanced congestive heart failure (CHF). If present, CSR clearly has a negative impact on the clinical course of CHF. Although the optimal treatment strategy for CSR is less well defined than that for OSA, the successful reversal of CSR might increase overall survival in affected patients.     

Sleep-disordered breathing in heart failure: characteristics and implications

Sleep-disordered breathing, namely obstructive sleep apnea (OSA) and central sleep apnea (CSA), are both often encountered in the setting of heart failure (HF), and have distinct differences in terms of prevalence, pathophysiology and consequences. OSA is independently associated with an increased risk for cardiovascular disease and for congestive HF in the general population. It is conceivable that this breathing disorder may have particularly deleterious effects in patients with coexisting heart disease, especially in those with a failing heart. There are considerable data addressing the interaction between OSA and the cardiovascular system, which underscore the importance of an early detection of this breathing disorder, especially in patients with HF. CSA is generally considered a consequence rather than a cause of HF, and is correlated with the severity of hemodynamic impairment. However, when present, it is associated with increased arrhythmic risk and higher cardiac mortality. Potential mechanisms implicated in the genesis of this breathing pattern and the possible therapeutic options, which have been proven to be effective in the clinical setting, are discussed.     

Electroencephalographic arousals during sleep do not alter the pressor response to Cheyne-Stokes respiration in subjects with chronic heart failure

This study examined the influence of electroencephalographic (EEG) arousal on the magnitude and morphology of the pressor response to Cheyne-Stokes respiration (CSR) in subjects with congestive heart failure (CHF). Thirteen subjects with stable CHF (left ventricular ejection fraction, 26 +/- 7%) and CSR (apnea-hypopnea index 52 +/- 15 h(-1)) underwent overnight polysomnography with beat-to-beat measurement of systemic arterial blood pressure (BP). CSR events were divided into those with or without an EEG arousal defined according to the criteria of the American Sleep Disorders Association. The pressor response was quantified in terms of the delta BP change (difference between the minimum BP during apnea and maximum BP during hyperpnea). Changes in the morphology of the pressor response were assessed by subdividing individual respiratory events into six periods (three during apnea: A1, A2, A3; and three during hyperpnea: H1, H2, H3). Considerable fluctuations in BP and heart rate (HR) were observed across the CSR cycle (delta mean BP 20.2 +/- 6.5 mmHg). The presence of an EEG arousal did not alter the amplitude of fluctuations in BP. Mean blood pressure (MBP) increased 21.0 +/- 7.5 mmHg with arousal versus 19.3 +/- 5.8 mmHg without arousal (NS). A repeated measures ANOVA showed no significant interaction between the presence of arousal and the proportional change in mean BP across the six periods, indicating that an EEG arousal had no effect on the morphology of MBP change during CSR [F(5,60) = 1.44, P = 0.22]. This study showed that EEG-defined arousal does not amplify the pressor response to CSR in CHF.     

Association of right ventricular dysfunction and Cheyne-Stokes respiration in patients with chronic heart failure

Cheyne-Stokes respiration (CSR) is present in up to 40% of patients with congestive heart failure (CHF) and is an independent risk factor for increased overall mortality. We examined whether CSR is associated with right ventricular (RV) dysfunction in CHF patients. Parameters of RV function were assessed by two-dimensional echocardiography and tissue velocity imaging in 42 patients (aged 23-75 years) with a left ventricular (LV) ejection fraction below 40%. Respiratory polygraphy revealed CSR with an central apnea-hypopnea index (CAHI) >10 h-1 in 13 of the 42 patients (31%). Demographic characteristics did not differ among the patient groups. The velocity of the tricuspid annular systolic motion (TASM), a parameter reflecting systolic RV function, was significantly reduced in CHF patients with CSR (10.5 +/- 2.3 cm s-1) compared with those without CSR (15.0 +/- 5.1 cm s-1, P = 0.004), and was inversely associated with the CAHI (y = 15.2-0.2x; r = 0.46, P = 0.003). The RV dimensions were significantly increased and the fractional RV area changes significantly reduced in CHF patients with CSR (33 +/- 17 versus 48 +/- 20%; P = 0.04). Doppler parameters of pulmonary artery flow indicate higher pulmonary artery pressures in CSR patients compared with patients without CSR, which is also reflected by an increased RV free-wall thickness in CSR patients (6.5 +/- 1.1 vs. 5.3 +/- 1.3 mm; P = 0.05). Parameters of systolic LV function, forced expiratory volume in 1 s (FEV1), and PaO2 and PaCO2 were not different among patients with or without CSR. In conclusion, CSR is associated with depressed systolic RV function and increased RV dimensions in CHF patients. Future studies will show whether optimized treatment of CSR will improve RV function.     

Heart rate increment analysis is not effective for sleep-disordered breathing screening in patients with chronic heart failure

Frequency domain analysis of heart rate variation has been suggested as an effective screening tool for sleep-disordered breathing (SDB) in the general population. The aim of this study was to assess this method in patients with chronic congestive heart failure (CHF). We included prospectively 84 patients with stable CHF, left ventricular ejection fraction (LVEF) <45% and sinus rhythm. The patients underwent polygraphy to measure the apnoea/hypopnoea index (AHI) and simultaneous Holter electrocardiogram monitoring to measure the power spectral density of the very low frequency component of the heart rate increment, expressed as the percentage of total power spectral density [% very low frequency increment (%VLFI)]. %VLFI could be determined in 54 patients (mean age, 52.8 ± 12.3 years; LVEF, 33.5 ± 9.8%). SDB defined as AHI ≥15 h⁻¹ was diagnosed in 57.4% of patients. Percent VLFI was not correlated with AHI ( r  =   0.12). Receiver-operating characteristic curves constructed using various AHI cut-offs (5–30 h⁻¹) failed to identify a %VLFI cut-off associated with SDB. The 2.4% VLFI cut-off recommended for the general population of patients with suspected SDB had low specificity (35%) and low positive and negative predictive values (35% and 54%, respectively). Heart rate increment analysis has several limitations in CHF patients and cannot be recommended as an SDB screening tool in the CHF population.     

Sleep-disordered breathing and psychomotor vigilance in a community-based sample

STUDY OBJECTIVE: Sleep-disordered breathing (SDB) has been associated with impaired psychomotor vigilance performance in patients with sleep apnea patients. A bias toward greater referral of sleep apnea patients with severely impaired performance could explain these findings. Furthermore, no studies on the association between SDB and vigilance performance in a large community-based sample have been reported that encompasses the full spectrum of SDB severity. This study investigated the association between SDB and psychomotor vigilance with cross-sectional data from the Wisconsin Sleep Cohort Study. SETTING AND PARTICIPANTS: Community-based sample of 265 women and 346 men, mean age of 53.0 +/- 7.9 (age range: 35-74) years was used. Within 6 months of completing an overnight polysomnography protocol for SDB assessment, participants completed a 10-minute psychomotor vigilance task (PVT) during a daytime protocol. MEASUREMENTS: Sleep-disordered breathing was indicated by the number of apneas and hypopneas; psychomotor vigilance task variables included (1) mean of 1/reaction time (RT), (2) number of lapses, (3) mean reciprocal of fastest 10% RTs, (4) mean reciprocal of slowest 10% RTs, (5) slope of linear regression line across the 10 minutes of the task fit to 1/RTs, and (5) number of false responses. RESULTS: Multiple regression analysis showed a significant negative association between the logarithmically transformed apnea-hypopnea index (LogAHI) and number of lapses, mean of the slowest 10%, and number of false responses from the psychomotor vigilance task, independent of sex and body mass index in participants aged 65 years and older. CONCLUSION: SDB in the community population is associated with impaired psychomotor vigilance in older men and women.     

Sympathetic activation in human heart failure: diverse mechanisms,therapeutic opportunities

Plasma noradrenaline (NA) concentrations relate both to the severity of heart failure, and to its impact on survival, but have shortcomings that limit their usefulness as measures of sympathetic discharge. Neural recordings and the isotopic dilution method for determining organ‐specific rates of NA spillover into plasma have enhanced our understanding of mechanisms responsible for sympathetic activation. Because the arterial baroreceptor reflex control of heart rate is impaired in heart failure, a parallel reduction in the reflex inhibition of sympathetic outflow has been assumed. However, human heart failure is characterized by rapidly responsive arterial baroreflex regulation of muscle sympathetic nerve activity (MSNA), attenuated cardiopulmonary reflex modulation of MSNA, and activation of a cardiac‐specific sympatho‐excitatory reflex related to increased cardiopulmonary filling pressures. Together, these baroreceptor mediated mechanisms account only, in part, for the time course and magnitude of adrenergic activation in heart failure. Non‐baroreflex sympatho‐excitatory mechanisms include: a metaboreflex arising from exercising skeletal muscle, mediated, in part, by adenosine, co‐existing sleep apnoea, and pre‐junctional facilitation of NA release. Thus, sympathetic activation in the setting of impaired systolic function reflects the net balance and interaction between augmented excitatory and diminished inhibitory influences. Variation, between patients, in the dynamics, magnitude and progression of sympathetic activation mandates an individualized approach to investigation and therapy. Excessive sympathetic outflow to the heart and periphery can be addressed by several complimentary strategies: attenuating these sympatho‐excitatory stimuli, modulating the neural regulation of NA release, and blocking the actions of catecholamines at post‐junctional receptors.     

Congestive heart failure and sleep apnoea—possible mechanisms and effect of CPAP therapy

SUMMARY  Sleep-disordered breathing has been associated with increased cardiovascular morbidity and mortality. However, despite several plausible mechanisms whereby obstructive sleep apnoea might be associated with left ventricular dysfunction and congestive heart failure, only limited data exist linking those disorders. These studies are reviewed along with possible mechanisms leading to left ventricular dysfunction in obstructive sleep apnoea. Recent investigations demonstrating improvement in left ventricular function after CPAP therapy in patients with congestive heart failure are reviewed as well. Finally, new data are presented from an animal model of congestive heart failure demonstrating a beneficial effect of CPAP on cardiac index in association with a decline in systematic vascular resistance. Remarkably, these effects persisted even after CPAP was removed. Possible mechanisms whereby CPAP may lead to improvement in cardiac output are discussed.     

Behavioral Correlates of Sleep-Disordered Breathing in Older Men

Study Objectives:

To examine the association between sleep-disordered breathing (SDB) and subjective measures of daytime sleepiness, sleep quality, and sleep-related quality of life in a large cohort of community-dwelling older men and to determine whether any association remained after adjustment for sleep duration.

Design:

Cross-sectional. The functional outcome measures of interest were daytime sleepiness (Epworth Sleepiness Scale, ESS), sleep-related symptoms (Pittsburgh Sleep Quality Index, PSQI), and sleep-related quality of life (Functional Outcomes of Sleep Questionnaire, FOSQ). Analysis of variance and adjusted regression analyses examined the association between these outcome measures and SDB severity and actigraphy-determined total sleep time (TST). We then explored whether associations with SDB were confounded by sleep duration by adjusting models for TST.

Setting:

Community-based sample in home and research clinic settings.

Participants:

Two-thousand eight-hundred forty-nine older men from the multicenter Osteoporotic Fractures in Men Study that began in 2000. All participants underwent in-home polysomnography for 1 night and wrist actigraphy for a minimum of 5 consecutive nights.

Interventions:

N/A.

Measurements and Results:

Participants were aged 76.4 ± 5.5 years and had an apnea-hypopnea index (AHI) of 17.0 ± 15.0. AHI and TST were weakly correlated. ESS scores individually were modestly associated with AHI and TST, but the association with AHI was attenuated by adjustment for TST. PSQI and FOSQ scores were largely not associated with measures of SDB severity but were modestly associated with TST.

Conclusions:

Daytime sleepiness, nighttime sleep disturbances, and sleep-related quality of life were modestly associated with TST. After adjustment for TST, there was no independent association with SDB severity. These results underscore the potential differences in SDB functional outcomes in older versus young and middle-aged adults.

Citation:

Kezirian EJ; Harrison SL; Ancoli-Israel S; Redline S; Ensrud K; Goldberg AN; Claman DM; Spira AP; Stone KL. Behavioral correlates of sleep-disordered breathing in older men. SLEEP 2009;32(2):253–261.     

Daytime sleepiness and neural cardiac modulation in sleep-related breathing disorders

Sleep-related breathing disorders are common causes of excessive daytime sleepiness, a socially and clinically relevant problem. Mechanisms responsible for daytime sleepiness are still largely unknown. We investigated whether specific alterations in autonomic cardiac modulation during sleep, commonly associated with sleep-related breathing disorders, are related to excessive daytime sleepiness. Fifty-three patients with sleep-related breathing disorders underwent nocturnal polysomnography. Excessive daytime sleepiness was diagnosed as a Multiple Sleep Latency Test response less than or equal to 600 s. We explored the relation of excessive daytime sleepiness, objectively determined, with indices of autonomic cardiac regulation, such as baroreflex sensitivity and heart rate variability, with polysomnographic indices of the severity of sleep-related breathing disorders and with quality of sleep. Patients with excessive daytime sleepiness, when compared with patients without, had significantly lower baroreflex sensitivity and significantly higher low-to-high frequency power ratio of heart rate variability during the different stages of nocturnal sleep. By contrast, no differences were found in indices quantifying the severity of sleep-related breathing disorders or sleep quality. We demonstrated that excessive daytime sleepiness is accompanied by a deranged cardiac autonomic control at night, the latter probably reflecting autonomic arousals not detectable in the EEG. As abnormal autonomic regulation is also known to be associated with increased cardiovascular risk, a possible relation between excessive daytime sleepiness and cardiovascular events in patients with sleep-related breathing disorders deserves to be investigated in future studies.     

Psychosocial factors and congestive heart failure

The incidence and prevalence of congestive heart failure (CHF) are increasing, even after adjustment for an aging population. Because coverage of psychosocial factors in CHF has been insufficient, we reviewed the literature in this area. Four major themes emerged in our review as we examined relations between psychosocial factors and CHF: psychiatric comorbidity, psychosocial precipitation and exacerbation of CHF, psychosocial consequences of CHF, and physiological mechanisms linking psychosocial factors and the course of CHF. There is a surprising paucity of studies in these areas. We tabulate the studies and discuss representative studies with an eye to directions for future research. This research was supported by Grants HL36005, HL44915, and RR00827 from the National Institutes of Health.     

Sleep apnea in heart failure increases heart rate variability and sympathetic dominance

AIMS: Sleep disordered breathing (SDB) is common in heart failure and ventilation is known to influence heart rate. Our aims were to assess the influence of SDB on heart rate variability (HRV) and to determine whether central sleep apnea (CSA) and obstructive sleep apnea (OSA) produced different patterns of HRV. METHODS AND RESULTS: Overnight polysomnography was performed in 21 patients with heart failure and SDB. Two 10-minute segments each of SDB and stable breathing from each patient were visually identified and ECG signal exported for HRV analysis. SDB increased total power (TP) with very low frequency (VLF) power accounting for the greatest increase (1.89+/-0.54 vs 2.96+/-0.46 ms2, P <0.001); LF/HF ratio increased during SDB (1.2+/-1.0 vs 2.7+/-2.1, P <0.001). Compared to OSA, CSA was associated with lower absolute LF (2.10+/-0.47 vs 2.52+/-0.55 ms2, P = 0.049) and HF power (1.69+/-0.41 vs 2.34+/-0.58 ms2, P = 0.004), increased VLF% (78.9%+/-13.4% vs 60.9%+/-19.2%, P = 0.008), decreased HF% (6.9%+/-7.8% vs 16.0%+/-11.7%, P = 0.046) with a trend to higher LF/HF ratio. CONCLUSIONS: SDB increases HRV in the setting of increased sympathetic dominance. HRV in CSA and OSA have unique HRV patterns which are likely to reflect the different pathophysiological mechanisms involved.     

Sleep problems and daytime somnolence in a German population-based sample of snoring school-aged children

Habitual snoring is associated with daytime symptoms like tiredness and behavioral problems. Its association with sleep problems is unclear. We aimed to assess associations between habitual snoring and sleep problems in primary school children. The design was a population-based cross-sectional study with a nested cohort study. The setting was twenty-seven primary schools in the city of Hannover, Germany. Habitual snoring and sleep problems were assessed in primary school children using an extended version of Gozal's sleep-disordered breathing questionnaire (n = 1144). Approximately 1 year later, parents of children reported to snore habitually (n = 114) and an equal number of children who snored never or occasionally were given the Sleep Disturbance Scale for Children, a validated questionnaire for the assessment of pediatric sleep problems. Snoring status was re-assessed using the initial questionnaire and children were then classified as long-term habitual snorers or ex-habitual snorers. An increasing prevalence of sleep problems was found with increasing snoring frequency for sleep-onset delay, night awakenings, and nightmares. Long-term habitual snorers were at significantly increased risk for sleep-wake transition disorders (e.g. rhythmic movements, hypnic jerks, sleeptalking, bruxism; odds ratio, 95% confidence interval: 12.0, 3.8-37.3), sleep hyperhidrosis (3.6, 1.2-10.8), disorders of arousal/nightmares (e.g. sleepwalking, sleep terrors, nightmares; 4.6, 1.3-15.6), and excessive somnolence (i.e. difficulty waking up, morning tiredness, daytime somnolence; 6.3, 2.2-17.8). Ex-habitual snorers were at increased risk for sleep-wake transition disorders (4.4, 1.4-14.2). Habitual snoring was associated with several sleep problems in our study. Long-term habitual snorers were more likely to have sleep problems than children who had stopped snoring spontaneously.     

Quality of life in heart failure patients undergoing hybrid comprehensive telerehabilitation versus usual care – results of the Telerehabilitation in Heart Failure Patients (TELEREH-HF) Randomized Clinical Trial

IntroductionHybrid comprehensive telerehabilitation (HCTR) consisting of telecare (with psychological telesupport), telerehabilitation and remote monitoring of implantable devices might be an innovative option improving heart failure (HF) patients’ quality of life (QoL) and emotional health. The aim of the study was to investigate the influence of HCTR on various facets of QoL in HF patients in comparison with usual care (UC) alone.Material and methodsThe present analysis formed part of a multicenter, randomized trial that enrolled 850 HF patients (NYHA I–III, LVEF ≤ 40%). Patients were randomized 1 : 1 to HCTR plus UC or UC only. Patients underwent either an HCTR program or UC with observation. The psychological intervention in the HCTR group included supportive psychological counseling via mobile phone. The Medical Outcome Survey Short Form 36 Questionnaire was used to assess QoL. Measurements were made before and after a 9-week intervention (HCTR group)/observation (UC group).ResultsAfter the intervention, the HCTR group showed significant improvement in overall QoL, physical domain (PD) of QoL, and 4 areas of QoL (physical functioning (PhF), role functioning related to physical state (RF), general health (GH), vitality (VI)). A significant positive change in QoL in the UC group was observed only in VI and social functioning. There were also significant differences in QoL after 9-week intervention/observation between the two groups. The results showed greater improvement in HCTR for overall QoL (p = 0.009), PD of QoL (p = 0.0003) and three specific areas of QoL: PhF (p = 0.001), RF (p = 0.003), bodily pain (BP) (p = 0.015).ConclusionsIn comparison to UC, HCTR resulted in improvement in overall QoL, PD of QoL and 3 specific areas of QoL: PhF, RF and BP.     

Insomnia Symptoms and Daytime Function in Stable Heart Failure

Objectives:

To evaluate insomnia symptoms and the extent to which they are associated with clinical and demographic patient characteristics, daytime symptoms, and functional performance in patients with stable heart failure (HF).

Design:

Cross-sectional, observational.

Setting:

Five structured HF disease management programs in the Northeastern U.S.

Participants:

173 stable chronic HF patients

Interventions:

N/A

Measurements and Results:

Full polysomnography was obtained for one night in participants'' homes. Participants completed the six-minute walk test, Medical Outcomes Study SF-36, Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Multi-Dimensional Assessment of Fatigue Scale, Centers for the Epidemiological Studies of Depression Scale, and questionnaire items eliciting insomnia symptoms (self-reported difficulty initiating and maintaining sleep and waking too early in the morning). Over half of HF patients reported insomnia symptoms. These were associated with increased daytime symptoms (depression, fatigue), excessive daytime sleepiness, and functional performance in models that statistically controlled for clinical and demographic covariates. These relationships were not explained by sleep disordered breathing.

Conclusions:

Insomnia symptoms are common in patients with stable heart failure and are associated with daytime symptoms and decrements in functional performance.

Citation:

Redeker NS; Jeon S; Muench U; Campbell D; Walsleben J; Rapoport DM. Insomnia symptoms and daytime function in stable heart failure. SLEEP 2010;33(9):1210-1216.     

Cardiovascular disease and health-care utilization in snorers: a population survey

STUDY OBJECTIVES: We assessed the prevalence of self-reported snoring in the Hungarian population and established whether different types of snoring are associated with cardiovascular disorders and increased health-care utilization. DESIGN: Cross-sectional study. Door-to-door survey. SETTING: Nationally representative population in Hungary. PARTICIPANTS: Interviews were carried out in the homes of 12,643 persons. We used the Hungarian National Population Register as the sampling frame and implemented a clustered, stratified sampling procedure. The study population represented 0.16% of the population over the age of 18 years according to age, sex, and 150 subregions of the country. INTERVENTIONS: Not applicable. MEASUREMENTS AND RESULTS: Thirty-seven percent of men and 21% of women reported loud snoring with breathing pauses. Hypertension, myocardial infarction, and stroke were reported by 26%, 3%, and 4% of the respondents, respectively. There was a significant increase in the prevalence of hypertension, myocardial infarction, and stroke in quiet and loud snorers, as compared with nonsnorers. Multivariate analysis showed an association between loud snoring and hypertension (odds ratio [OR]: 1.40, 95% confidence interval [CI]: 1.24-1.58), myocardial infarction (OR: 1.34, CI: 1.04-1.73), and stroke (OR: 1.67, CI: 1.32-2.11) after statistical adjustment for age, sex, body mass index, diabetes, level of education, smoking, and alcohol consumption. Loud snoring was also associated with measures of health-care use in both sexes. CONCLUSIONS: Snoring is frequent in the Hungarian adult population, and loud snoring with breathing pauses, in contrast with quiet snoring, is associated with an increased risk of cardiovascular disease and increased health-care utilization.     

Cyclic alternating pattern in children with obstructive sleep apnea and its relationship with adenotonsillectomy,behavior, cognition,and quality of life

Study ObjectivesTo determine in children with obstructive sleep apnea (OSA) the effect of adenotonsillectomy (AT) on the cyclic alternating pattern (CAP) and the relationship between CAP and behavioral, cognitive, and quality-of-life measures.MethodsCAP parameters were analyzed in 365 overnight polysomnographic recordings of children with mild-to-moderate OSA enrolled in the Childhood Adenotonsillectomy Trial (CHAT), randomized to either early AT (eAT) or watchful waiting with supportive care (WWSC). We also analyzed CAP in a subgroup of 72 children with moderate OSA (apnea–hypopnea index > 10) that were part of the CHAT sample. Causal mediation analysis was performed to determine the independent effect of changes in CAP on selected outcome measures.ResultsAt baseline, a higher number of A1 phases per hour of sleep was significantly associated with worse behavioral functioning (caregiver Behavior Rating Inventory of Executive Function (BRIEF) Global Executive Composite (GEC): ρ = 0.24, p = 0.042; caregiver Conners’ Rating Scale Global Index: ρ = 0.25, p = 0.036) and lower quality of life (OSA-18: ρ = 0.27, p = 0.022; PedsQL: ρ = −0.29, p = 0.015) in the subgroup of children with moderate OSA, but not across the entire sample. At 7-months follow-up, changes in CAP parameters were comparable between the eAT and WWSC arms. CAP changes did not account for significant proportions of variations in behavioral, cognitive, and quality-of-life performance measures at follow-up.ConclusionsWe show a significant association between the frequency of slow, high-amplitude waves with behavioral functioning, as well as the quality of life in children with moderate OSA. Early AT in children with mild-to-moderate OSA does not alter the microstructure of nonrapid eye movement sleep compared with watchful waiting after an approximately 7-month period of follow-up.Clinical TrialThe study “A Randomized Controlled Study of Adenotonsillectomy for Children With Obstructive Sleep Apnea Syndrome” was registered at Clinicaltrials.gov (#{"type":"clinical-trial","attrs":{"text":"NCT00560859","term_id":"NCT00560859"}}NCT00560859).