Showing papers by "Peretz Lavie published in 2007"

Gender-related differences in symptoms of patients with suspected breathing disorders in sleep: a clinical population study using the sleep disorders questionnaire.

Abstract: Background: Gender-related differences in the symptom profile of patients with suspected sleep disordered breathing (SDB) may be one explanation of the clinical underrecognition of SDB in women. Study Objectives: The aim of this study was to prospectively assess gender-related differences in presenting symptoms in a clinical sample of patients with suspected sleep disordered breathing. Design: Administration of the Sleep Disorders Questionnaire prior to clinical and polysomnographic evaluation. Responses obtained from the questionnaire were used to construct 4 independent symptom scales: sleep apnea (SA), periodic limb movement syndrome (PLM), psychiatric sleep disorder (PSY), and narcolepsy (NAR). Analyses of variance were used to examine the effect of gender, AHI, and age on the symptom scales. Associations between gender and each diagnostic scale of the questionnaire were determined by multiple analyses of covariance. Setting: Tertiary pulmonary referral center. Participants: 2739 men and 782 women with suspected SDB. All patients who were referred to the sleep laboratory underwent full-night polysomnography, irrespective of the likelihood of SDB. Interventions: N/A Measurements and Results: Overall, men scored significantly higher on items related to worsening of snoring/breathing with alcohol (P 15/hr. In contrast, women complained significantly more often of insomnia, restless legs, depression, nightmares, palpitations at night, and hallucinations than men. As a result, women had significantly higher scores on the PLM, PSY, and NAR scales of the Sleep Disorders Questionnaire (P <0.001, for all). After adjustments for age, body mass index, AHI, arousal index, oxygen saturation data, and smoking history, by means of multiple analyses of covariances, gender differences remained significant (P <0.001, for all scales). Conclusions: We observed significant gender-related differences in presenting symptoms of patients with sleep disordered breathing at a tertiary level. These differences should be taken into consideration in clinical evaluation of women with suspected sleep disordered breathing.

Mortality risk factors in sleep apnoea: a matched case-control study.

Abstract: Sleep apnoea syndrome was reported to be associated with increased mortality but it is not known if this association is independent of obesity and co-morbidities. The present study investigated predictors of mortality in a large cohort of men with sleep apnoea using a case-control design. The study population consisted of 10,981 men diagnosed during 1991-2000 by whole-night polysomnography with sleep apnoea; 331 men died prior to 1 September 2001, of whom 277 were matched by age, gender, site and time of study to patients who were alive in September 2001. Multivariate analysis revealed that all-cause mortality was associated with chronic obstructive pulmonary disease (COPD) (odds ratio, OR: 7.07, 95% CI 2.75-18.16), chronic heart failure (CHF) (OR: 5.47, 95% CI 1.06-28.31), diabetes mellitus (DM) (OR: 3.30, 95% CI 1.51-7.20) and body mass index (BMI) (increase of 5 kg m(-2), OR: 1.44, 95% CI: 1.04-1.99). Chronic upper airway problems were associated with survival (OR: 0.45, 95% CI 0.23-0.90). There were significant interactions between respiratory disturbance index and BMI and COPD. Mortality of patients younger than the median age (62 years) was associated with COPD, DM and an interaction between BMI and apnoea severity. Predictors of mortality for the older patients were COPD, CHF and DM. We conclude that all-cause mortality in sleep apnoea is associated with co-morbidities and obesity. Severity of sleep apnoea affects mortality by interacting with obesity and lung disease.

Detecting REM sleep from the finger: an automatic REM sleep algorithm based on peripheral arterial tone (PAT) and actigraphy.

Abstract: Scoring of REM sleep based on polysomnographic recordings is a laborious and time-consuming process. The growing number of ambulatory devices designed for cost-effective home-based diagnostic sleep recordings necessitates the development of a reliable automatic REM sleep detection algorithm that is not based on the traditional electroencephalographic, electrooccolographic and electromyographic recordings trio. This paper presents an automatic REM detection algorithm based on the peripheral arterial tone (PAT) signal and actigraphy which are recorded with an ambulatory wrist-worn device (Watch-PAT100). The PAT signal is a measure of the pulsatile volume changes at the finger tip reflecting sympathetic tone variations. The algorithm was developed using a training set of 30 patients recorded simultaneously with polysomnography and Watch-PAT100. Sleep records were divided into 5 min intervals and two time series were constructed from the PAT amplitudes and PAT-derived inter-pulse periods in each interval. A prediction function based on 16 features extracted from the above time series that determines the likelihood of detecting a REM epoch was developed. The coefficients of the prediction function were determined using a genetic algorithm (GA) optimizing process tuned to maximize a price function depending on the sensitivity, specificity and agreement of the algorithm in comparison with the gold standard of polysomnographic manual scoring. Based on a separate validation set of 30 patients overall sensitivity, specificity and agreement of the automatic algorithm to identify standard 30 s epochs of REM sleep were 78%, 92%, 89%, respectively. Deploying this REM detection algorithm in a wrist worn device could be very useful for unattended ambulatory sleep monitoring. The innovative method of optimization using a genetic algorithm has been proven to yield robust results in the validation set.

Validation of the BiteStrip screener for sleep bruxism.

Abstract: Objective The aim of this study was to validate a small electronic electromyographic device (BiteStrip) designed to screen masseter electromyographic events that indicate sleep bruxism (SB) against traditional masseter electromyographic events (MEMG). Study design Six SB treatment-seeking patients, 4 obstructive sleep apnea (OSA) patients and 8 symptom-free controls, underwent overnight polysomnography, including MEMG and BiteStrip recordings. Total BiteStrip and MEMG scores and indices (events per hour) based on total recording time (TRT) and total sleep time (TST) were computed. Measures of accuracy, Spearman’s rho correlations, and nonparametric group comparisons were performed. Results BiteStrip average sensitivity was 0.72, average positive predictive value was 0.75. Correlations between left BiteStrip and MEMG total scores, TRT, and TST indices were r = 0.81, r = 0.79, and r = 0.79, respectively. Bland-Altman plots showed good agreement between indices. Significant group differences were observed for total scores and indices. Conclusions BiteStrip and MEMG scores showed strong relationships. Sensitivity and positive predictive value were acceptable. The BiteStrip is a viable screener for identifying masseter electromyographic events that indicate SB.

Mortality in sleep apnoea syndrome: a review of the evidence

Abstract: Sleep apnoea syndrome is associated with cardiovascular morbidity, but it is less clear if it is also associated with increased mortality. Studies investigating mortality in sleep apnoea have 1) compared mortality rates of patients with different levels of severity of the syndrome relying on sleep laboratory populations, 2) compared treated and untreated patients, 3) examined the effect of co-existing cardiovascular diseases on survival and 4) investigated the effect of sleep-disordered breathing on mortality in the elderly. In spite of methodological limitations, the accumulated data generally support an increased risk of mortality in patients with severe sleep apnoea in comparison with mild or no sleep apnoea, and indicate that efficient treatment decreases mortality. Surprisingly, several studies have shown that the highest risk of mortality in sleep apnoea occurs in patients younger than 50 yrs of age, that risk tends to decline with age and that the occurrence of disordered breathing in sleep in the elderly does not affect mortality. It is as yet unclear if this finding represents a selection bias, differences in apnoea severity or in compliance with treatment between young and old patients, or an adaptation to the syndrome with age. There is conflicting evidence as to whether the occurrence of sleep apnoea in patients with existing cardiovascular diseases increases the risk of mortality beyond that associated with the cardiovascular diseases themselves.

Relation of C-reactive protein to coronary collaterals in patients with stable angina pectoris and coronary artery disease.

Abstract: The heterogeneity in the degree of collateralization among patients with coronary artery disease (CAD) is poorly understood. We sought to determine whether chronic subclinical inflammation is related to coronary collateral development in patients with chronic stable angina pectoris and obstructive CAD. High-sensitivity C-reactive protein (CRP) levels were measured in 177 patients with stable angina pectoris before coronary angiography. Multivariable logistic regression revealed an inverse graded association between CRP and the presence of coronary collaterals (Rentrop grade 1 to 3). Compared with patients in the first CRP tertile, the adjusted odds ratio for the presence of coronary collaterals was 0.70 (95% confidence interval, 0.33 to 1.52; p = 0.45) for patients in the second CRP tertile and 0.33 (95% confidence interval, 0.15 to 0.75; p = 0.008) for patients in the third CRP tertile (p for trend = 0.008). In conclusion, an inverse graded association exists between CRP and the presence of coronary collaterals in patients with stable angina pectoris.

Elevated plasma homocysteine in older shift-workers: a potential risk factor for cardiovascular morbidity.

Abstract: There is evidence supporting an association between shift work and cardiovascular morbidity, but the underlying mechanisms are unknown. The present paper investigated the levels of cardiovascular biochemical risk factors in shift-workers both with (n=26) and without (n=103) sleep complaints, and in day-workers (n=173) working in the same plant. Blood samples were taken in the morning after an overnight fast and analyzed for homocysteine, C-reactive protein, and lipid profile. Biochemical data were compared among groups after stratifying workers by age (i.e., or = 40 yrs). Shift-workers who complained about sleep disturbances and who were > or = 40 years of age had significantly higher levels of homocysteine than did their younger counterparts - shift-workers who did not complain of sleep disturbances and day-workers. There were no other between-group differences in any of the biochemical variables. The results of this investigation demonstrate an association between sleep disturbances in older shift-workers and mild hyperhomocysteinemia. The elevated homocysteine levels may play a role in the increased rates of cardiovascular morbidity in shift-workers, and they may have practical implications regarding the nutrition of shift-workers.

Peripheral arterial tone as an on-line measure of load in a simulated flight task.

Abstract: Variations in continuous and discrete flight demands were investigated in a simulated flight mission measuring peripheral arterial tone (PAT) from the tip of the finger. A total of 12 participants performed a computer-simulated agricultural flight task. They were required to fly over a specific lane of a simulated corn field (continuous task) and change lanes in response to flags, which appeared at varying intervals (discrete task). The difficulty of the flight task was manipulated by varying the airplane control (single- vs. dual-axis control), while the difficulty of the discrete task was manipulated by varying the amount of lateral change signalled by the flag. PAT amplitude was lower in the difficult level of the continuous task and was further attenuated following the appearance of the flag only when a change in the flight position was required. These results suggest the potential utility of PAT as an on-line measure of the joint continuous and discrete demands of a flight mission.

Oxidative stress and systemic inflammation in patients with sleep apnea: Role of obesity

Abstract: Oxidative stress and systemic inflammation resulting from repeated hypoxia/reoxygenation cycles in obstructive sleep apnea-hypopnea syndrome (OSAHS) play a role in atherogenesis. It is unclear, however, if this association is independent of obesity. The aims of the present study were to compare markers of oxidative stress and systemic inflammation between patients with and without OSAHS independent of obesity, and to examine their interrelations. In experiment 1, 20 OSAHS patients, age 42.1 ± 10.0 years, body mass index 26.3 ± 2.7 kg/m2, and apnea-hypopnea index 28.8 ± 10.8 events/h, were individually matched with 20 control subjects, age 41.5 ± 11.1 years, body mass index 26.0 ± 2.9, and apnea-hypopnea index 6.5 ± 2.4 events/h. In experiment 2, 15 OSAHS patients with body mass index > 27 were individually matched with 15 OSAHS patients having the same age and similar apnea severity with body mass index < 27. In both experiments, blood was drawn at the end of the sleep study for determination of lipid peroxidation markers, thiobarbituric-acid-reactive substances (TBARS) and peroxides and the antioxidant enzyme paraoxonase-1, and the systemic inflammatory markers C-reactive protein (CRP), ceruloplasmin and haptoglobin. OSAHS patients had significantly higher concentrations of TBARS (P < 0.0002) and peroxides (P < 0.03) and lower paraoxonase-1 (P < 0.02) than controls. No differences were found for the inflammatory markers but only in OSAHS patients there were significant correlations between the lipid peroxidation and inflammatory markers. There were no differences in lipid peroxidation between obese and non-obese patients, but CRP was higher (P < 0.03) in the obese patients. We conclude that sleep apnea is primarily associated with increased oxidative stress. Possibly, OSAHS influences systemic inflammatory pathways indirectly through oxidative stress.

Is the severity of sleep apnea associated with ischemic stroke in the elderly

Abstract: To the Editor: We read with great interest the article by Munoz et al,1 who reported that severe sleep apnea defined as apnea-hypopnea index (AHI) ≥30 significantly increased the risk of ischemic stroke in an elderly population (aged 70 to 100 years) independently of known confounding factors. If true, these findings may have enormous public health implications because almost 1 in 4 participants examined by Munoz et al fell into the category of severe sleep apnea. However, before any firm conclusions can be drawn from this study, the data presented in this article must be clarified. The authors compared 6-year incidence of ischemic stroke between elderly with AHI ≥30 and elderly with AHI <30 events/h, as documented by polysomnography. But the presented data on sleep apnea severity raise some important questions. The severity of sleep apnea is usually indexed by 2 measures, the rate of respiratory events—apneas and hypopneas—as used by …

and Endothelial Function Obstructive Sleep Apnea, Oxidative Stress, Herbst Mandibular Advancement Splint on The Effects of 1-Year Treatment With a

Abstract: 2007;131;740-749 Chest Giora Pillar Sarah Itzhaki, Hezi Dorchin, Glenn Clark, Lena Lavie, Peretz Lavie and and Endothelial Function Obstructive Sleep Apnea, Oxidative Stress, Herbst Mandibular Advancement Splint on The Effects of 1-Year Treatment With a http://chestjournals.org/cgi/content/abstract/131/3/740 and services can be found online on the World Wide Web at: The online version of this article, along with updated information ). ISSN: 0012-3692. http://www.chestjournal.org/misc/reprints.shtml ( of the copyright holder may be reproduced or distributed without the prior written permission Northbrook IL 60062. All rights reserved. No part of this article or PDF by the American College of Chest Physicians, 3300 Dundee Road, 2007 Physicians. It has been published monthly since 1935. Copyright CHEST is the official journal of the American College of Chest