@article {701, title = {Measures of cognitive function in persons with varying degrees of sleep-disordered breathing: the Sleep Heart Health Study.}, journal = {J Sleep Res}, volume = {11}, year = {2002}, month = {2002 Sep}, pages = {265-72}, abstract = {

Epidemiologic literature suggests that persons with clinically diagnosed sleep apnoea frequently have impaired cognitive function, but whether milder degrees of sleep-disordered breathing (SDB) are associated with cognitive dysfunction in the general population is largely unknown. Approximately 1700 subjects free of clinically diagnosed SDB underwent at-home polysomnography (PSG) as part of the Sleep Heart Health Study (SHHS) and completed three cognitive function tests within 1-2 years of their PSG: the Delayed Word Recall Test (DWR), the WAIS-R Digit Symbol Subtest (DSS), and the Word Fluency test (WF). A respiratory disturbance index (RDI) was calculated as the number of apnoeas and hypopnoeas per hour of sleep. After adjustment for age, education, occupation, field centre, diabetes, hypertension, body-mass index, use of CNS medications, and alcohol drinking status, there was no consistent association between the RDI and any of the three cognitive function measures. There was no evidence of a dose-response relation between the RDI and cognitive function scores and the adjusted mean scores by quartiles of RDI never differed from one another by more than 5\% for any of the tests. In this sample of free-living individuals with mostly mild to moderate levels of SDB, the degree of SDB appeared to be unrelated to three measures of cognitive performance.

}, keywords = {Aged, Body Mass Index, Brain, Cognition Disorders, Cohort Studies, Female, Humans, Hypoxia, Male, Middle Aged, Neuropsychological Tests, Oxygen, Polysomnography, Severity of Illness Index, Sleep Apnea, Central}, issn = {0962-1105}, doi = {10.1046/j.1365-2869.2002.00308.x}, author = {Boland, Lori L and Shahar, Eyal and Iber, Conrad and Knopman, David S and Kuo, Tracy F and Nieto, F Javier} } @article {714, title = {Short-term variability of respiration and sleep during unattended nonlaboratory polysomnography--the Sleep Heart Health Study. [corrected].}, journal = {Sleep}, volume = {25}, year = {2002}, month = {2002 Dec}, pages = {843-9}, abstract = {

STUDY OBJECTIVES: To determine the short-term variability of indices of disturbed respiration and sleep during 2 nights of unattended nonlaboratory polysomnography conducted several months apart.

DESIGN: Participants were randomly selected using a block design with stratification on preliminary estimates of 2 criteria: respiratory disturbance index [RDI3\% (apnea or hypopnea events associated with > or = 3\% O2 desaturation): < 15/hour total sleep time, > or = 15/hour total sleep time] and sleep efficiency (SEff: < 85\% and > or = 85\%). The RDI and sleep data from initial and repeated polysomnography were compared.

SETTING: NA.

PARTICIPANTS: A subset of 99 participants in the Sleep Heart Health Study who agreed to have a repeat polysomnogram within 4 months of their original study.

INTERVENTIONS: NA.

MEASUREMENTS AND RESULTS: Acceptable repeat polysomnograms were obtained in 91 subjects (mean study interval: 77 +/- 18 [sd] days; range: 31-112 days). There was no significant bias in RDI between study nights using several different RDI definitions including RDI3\% and RDI4\% (apnea or hypopnea events associated with > or = 4\% O2 desaturation). Variability between studies estimated using intraclass correlations (ICC) ranged from 0.77 to 0.81. For subjects with a RDI3\% < 15, variability increased as a function of increasing RDI, but for those with a RDI3\% > or = 15, variability was constant. Body mass index, SEff, gender, or age did not directly predict RDI variability. Using RDI4\% cutpoints of < or = 5, < or = 10 and < or = 15 events per hour of sleep demonstrated that 79.1\%, 85.7\%, and 87.9\% of subjects, respectively, had the same classification of SDB status on both nights of study. There also was no significant bias in sleep staging, sleep efficiency, or arousal index between studies. However, variability was greater with ICC values ranging from 0.37 (\% time in REM) to 0.76 (arousal index).

CONCLUSION: In the Sleep Heart Health Study, accurate estimates of the severity of sleep-disordered breathing and the quality of sleep were obtained from a single night of unattended nonlaboratory polysomnography. These findings may be applicable to other large epidemiologic studies provided that similar recording techniques and quality-assurance procedures are followed.

}, keywords = {Adult, Aged, Aged, 80 and over, Apnea, Arousal, Body Mass Index, Circadian Rhythm, Electrocardiography, Electromyography, Electrooculography, Female, Humans, Male, Middle Aged, Oxygen Consumption, Polysomnography, Respiration, Sleep Apnea Syndromes, Sleep Stages, Time Factors}, issn = {0161-8105}, author = {Quan, Stuart F and Griswold, Michael E and Iber, Conrad and Nieto, F Javier and Rapoport, David M and Redline, Susan and Sanders, Mark and Young, Terry} } @article {694, title = {Underdiagnosis of sleep apnea syndrome in U.S. communities.}, journal = {Sleep Breath}, volume = {6}, year = {2002}, month = {2002 Jun}, pages = {49-54}, abstract = {

We hypothesize that clinical recognition rates for obstructive sleep apnea-hypoapnea syndrome (OSAHS) are influenced by comorbidity and demographic factors. Data on medical disorders, symptoms of sleep disorders, and cardiovascular risk factors gathered from 15,699 individuals in the Sleep Heart Health Study were compared. Participants were classified into three groups: those with a self-reported physician diagnosis of OSAHS, those with self-reported physician-diagnosed and -treated OSAHS, and those reporting both frequent snoring and daytime sleepiness (two-symptom group). Among all participants, 4.1\% reported two symptoms (range across sites: 1.55 to 7.23\%), whereas 1.6\% reported a physician diagnosis of OSAHS (range: 0.66 to 2.88\%) and 0.6\% reported physician diagnosis and treatment (range: 0.11 to 0.88\%). Recognized OSAHS groups were similar to the two-symptom group in age, having a sleeping partner, measured blood pressure, total cholesterol, and race. In a logistic model that included age along with characteristics found to vary significantly among the three groups (gender, body mass index [BMI], high-density lipoprotein cholesterol levels, hypertension), only male gender and BMI were increased in those with physician-diagnosed and -treated OSAHS. We conclude that disparities (especially in women and in those with lower BMI) exist between current recognition rates for OSAHS and the estimated prevalence by symptom report across the United States.

}, keywords = {Diagnosis, Differential, Diagnostic Errors, Female, Humans, Male, Middle Aged, Prevalence, Sleep Apnea Syndromes, United States}, issn = {1520-9512}, doi = {10.1007/s11325-002-0049-5}, author = {Kapur, Vishesh and Strohl, Kingman P and Redline, Susan and Iber, Conrad and O{\textquoteright}Connor, George and Nieto, Javier} } @article {784, title = {Polysomnography performed in the unattended home versus the attended laboratory setting--Sleep Heart Health Study methodology.}, journal = {Sleep}, volume = {27}, year = {2004}, month = {2004 May 01}, pages = {536-40}, abstract = {

STUDY OBJECTIVE: To compare polysomnographic recordings obtained in the home and laboratory setting.

DESIGN AND SETTING: Multicenter study comparing unsupervised polysomnography performed in the participant{\textquoteright}s home with polysomnography supervised at an academic sleep disorders center, using a randomized sequence of study setting. Sleep Heart Health Study (SHHS) standardized polysomnographic recording and scoring techniques were used for both settings.

PARTICIPANTS: 64 of 76 non-SHHS participants recruited from 7 SHHS field sites who had both a laboratory and home polysomnogram meeting acceptable quality criteria.

MEASUREMENTS AND RESULTS: Median sleep duration was greater in the home than in the laboratory (375 vs 318 minutes, respectively, P < .0001) as was sleep efficiency (86\% vs 82\%, respectively, P < .0024). Very small, but significant increases in percentage of rapid eye movement sleep and decreases in stage 1 sleep were noted in the laboratory. Employing multiple definitions of respiratory disturbance index (RDI), median RDI was similar in both settings (for example, RDI with 3\% desaturation: home 12.4, range 0.6-67; laboratory 9.5, range 0.1-93.4, P = .41). Quartile analysis of laboratory RDI showed moderate agreement with home RDI measurements. Based on the mean of laboratory and home RDI and using a cutpoint of 20, there was a biphasic distribution, with the RDI 3\% above 20 being more common in the recordings performed in the laboratory than in the home and below 20 being more common in the recordings performed in the home than in the laboratory. These differences could not be attributed to quality of recording, age, sex, or body mass index.

CONCLUSIONS: Using SHHS methodology, median RDI was similar in the unattended home and attended laboratory setting with differences of small magnitude in some sleep parameters. Differences in RDI between settings resulted in a rate of disease misclassification that is similar to repeated studies in the same setting.

}, keywords = {Adult, Aged, Body Mass Index, Clinical Laboratory Techniques, Cohort Studies, Health Status, Home Care Services, Humans, Middle Aged, Polysomnography, Sleep Apnea Syndromes, Sleep, REM}, issn = {0161-8105}, doi = {10.1093/sleep/27.3.536}, author = {Iber, Conrad and Redline, Susan and Kaplan Gilpin, Adele M and Quan, Stuart F and Zhang, Lin and Gottlieb, Daniel J and Rapoport, David and Resnick, Helaine E and Sanders, Mark and Smith, Philip} } @article {839, title = {Predictors of heartburn during sleep in a large prospective cohort study.}, journal = {Chest}, volume = {127}, year = {2005}, month = {2005 May}, pages = {1658-66}, abstract = {

BACKGROUND AND AIMS: Nocturnal gastroesophageal reflux, which may result in nocturnal heartburn, has been demonstrated to be associated with a more severe form of gastroesophageal reflux disease (GERD). The aim of this study was to determine the clinical predictors of heartburn during sleep in a large prospective cohort study.

METHODS: Study subjects were members of the parent cohorts from which the Sleep Heart Health Study (SHHS) recruited participants. SHHS is a multicenter, longitudinal, cohort study of the cardiovascular consequences of sleep-disordered breathing. As part of the recruitment process, parent cohort members completed a questionnaire that permitted an assessment of the relationships between heartburn during sleep, and patient demographics, sleep abnormalities, medical history, and social habits in nine community-based parent cohorts across the United States. All variables, significant at the p < 0.05 level, were included as independent variables in multivariate logistic regression models with heartburn during sleep status included as the dependent variable

RESULTS: A total of 15,314 subjects completed the questions about heartburn during sleep, and of these, 3,806 subjects (24.9\%) reported having this symptom. In four increasingly comprehensive multivariate models, increased body mass index (BMI), carbonated soft drink consumption, snoring and daytime sleepiness (Epworth sleepiness scale score), insomnia, hypertension, asthma, and usage of benzodiazepines were strong predictors of heartburn during sleep. In contrast, college education decreased the risk of reporting heartburn during sleep.

CONCLUSIONS: Heartburn during sleep is very common in the general population. Reports of this type of symptom of GERD are strongly associated with increased BMI, carbonated soft drink consumption, snoring and daytime sleepiness, insomnia, hypertension, asthma, and usage of benzodiazepines. Overall, heartburn during sleep may be associated with sleep complaints and excessive daytime sleepiness.

}, keywords = {Aged, Body Mass Index, Carbonated Beverages, Cohort Studies, Educational Status, Female, Gastroesophageal Reflux, Heartburn, Humans, Male, Middle Aged, Multivariate Analysis, Prospective Studies, Sleep, Surveys and Questionnaires}, issn = {0012-3692}, doi = {10.1378/chest.127.5.1658}, author = {Fass, Ronnie and Quan, Stuart F and O{\textquoteright}Connor, George T and Ervin, Ann and Iber, Conrad} }