@article {993, title = {Power spectral analysis of EEG activity during sleep in cigarette smokers.}, journal = {Chest}, volume = {133}, year = {2008}, month = {2008 Feb}, pages = {427-32}, abstract = {

BACKGROUND: Research on the effects of cigarette smoking on sleep architecture is limited. The objective of this investigation was to examine differences in sleep EEG between smokers and nonsmokers.

METHODS: Smokers and nonsmokers who were free of all medical comorbidities were matched on different factors, including age, gender, race, body mass index, and anthropometric measures. Home polysomnography was conducted using a standard recording montage. Sleep architecture was assessed using visual sleep-stage scoring. The discrete fast Fourier transform was used to calculate the EEG power spectrum for the entire night within contiguous 30-s epochs of sleep for the following frequency bandwidths: delta (0.8 to 4.0 Hz); theta (4.1 to 8.0 Hz); alpha (8.1 to 13.0 Hz); and beta (13.1 to 20.0 Hz).

RESULTS: Conventional sleep stages were similar between the two groups. However, spectral analysis of the sleep EEG showed that, compared to nonsmokers, smokers had a lower percentage of EEG power in the delta-bandwidth (59.7\% vs 62.6\%, respectively; p < 0.04) and higher percentage of EEG power in alpha-bandwidth (15.6\% vs 12.5\%, respectively; p < 0.001). Differences in the EEG power spectrum between smokers and nonsmokers were greatest in the early part of the sleep period and decreased toward the end. Subjective complaints of lack of restful sleep were also more prevalent in smokers than in nonsmokers (22.5\% vs 5.0\%, respectively; p < 0.02) and were explained, in part, by the differences in EEG spectral power.

CONCLUSIONS: Cigarette smokers manifest disturbances in the sleep EEG that are not evident in conventional measures of sleep architecture. Nicotine in cigarette smoke and withdrawal from it during sleep may contribute to these changes and the subjective experience of nonrestorative sleep.

}, keywords = {Electroencephalography, Female, Humans, Logistic Models, Male, Middle Aged, Polysomnography, Sleep, Smoking, Spectroscopy, Fourier Transform Infrared}, issn = {0012-3692}, doi = {10.1378/chest.07-1190}, author = {Zhang, Lin and Samet, Jonathan and Caffo, Brian and Bankman, Isaac and Punjabi, Naresh M} } @article {1215, title = {Prospective study of obstructive sleep apnea and incident coronary heart disease and heart failure: the sleep heart health study.}, journal = {Circulation}, volume = {122}, year = {2010}, month = {2010 Jul 27}, pages = {352-60}, abstract = {

BACKGROUND: Clinic-based observational studies in men have reported that obstructive sleep apnea is associated with an increased incidence of coronary heart disease. The objective of this study was to assess the relation of obstructive sleep apnea to incident coronary heart disease and heart failure in a general community sample of adult men and women.

METHODS AND RESULTS: A total of 1927 men and 2495 women > or =40 years of age and free of coronary heart disease and heart failure at the time of baseline polysomnography were followed up for a median of 8.7 years in this prospective longitudinal epidemiological study. After adjustment for multiple risk factors, obstructive sleep apnea was a significant predictor of incident coronary heart disease (myocardial infarction, revascularization procedure, or coronary heart disease death) only in men < or =70 years of age (adjusted hazard ratio 1.10 [95\% confidence interval 1.00 to 1.21] per 10-unit increase in apnea-hypopnea index [AHI]) but not in older men or in women of any age. Among men 40 to 70 years old, those with AHI > or =30 were 68\% more likely to develop coronary heart disease than those with AHI <5. Obstructive sleep apnea predicted incident heart failure in men but not in women (adjusted hazard ratio 1.13 [95\% confidence interval 1.02 to 1.26] per 10-unit increase in AHI). Men with AHI > or =30 were 58\% more likely to develop heart failure than those with AHI <5.

CONCLUSIONS: Obstructive sleep apnea is associated with an increased risk of incident heart failure in community-dwelling middle-aged and older men; its association with incident coronary heart disease in this sample is equivocal.

}, keywords = {Adult, Aged, Coronary Disease, Female, Heart Failure, Humans, Longitudinal Studies, Male, Middle Aged, Polysomnography, Proportional Hazards Models, Prospective Studies, Sleep Apnea, Obstructive, Survival Analysis}, issn = {1524-4539}, doi = {10.1161/CIRCULATIONAHA.109.901801}, author = {Gottlieb, Daniel J and Yenokyan, Gayane and Newman, Anne B and O{\textquoteright}Connor, George T and Punjabi, Naresh M and Quan, Stuart F and Redline, Susan and Resnick, Helaine E and Tong, Elisa K and Diener-West, Marie and Shahar, Eyal} }