@article {645, title = {Methods for obtaining and analyzing unattended polysomnography data for a multicenter study. Sleep Heart Health Research Group.}, journal = {Sleep}, volume = {21}, year = {1998}, month = {1998 Nov 01}, pages = {759-67}, abstract = {

This paper reviews the data collection, processing, and analysis approaches developed to obtain comprehensive unattended polysomnographic data for the Sleep Heart Health Study, a multicenter study of the cardiovascular consequences of sleep-disordered breathing. Protocols were developed and implemented to standardize in-home data collection procedures and to perform centralized sleep scoring. Of 7027 studies performed on 6697 participants, 5534 studies were determined to be technically acceptable (failure rate 5.3\%). Quality grades varied over time, reflecting the influences of variable technician experience, and equipment aging and modifications. Eighty-seven percent of studies were judged to be of "good" quality or better, and 75\% were judged to be of sufficient quality to provide reliable sleep staging and arousal data. Poor submental EMG (electromyogram) accounted for the largest proportion of poor signal grades (9\% of studies had <2 hours artifact free EMG signal). These data suggest that with rigorous training and clear protocols for data collection and processing, good-quality multichannel polysomnography data can be obtained for a majority of unattended studies performed in a research setting. Data most susceptible to poor signal quality are sleep staging and arousal data that require clear EEG (electroencephalograph) and EMG signals.

}, keywords = {Electroencephalography, Electromyography, Feasibility Studies, Humans, Licensure, Polysomnography, Research Design, Sleep Apnea Syndromes, Teaching}, issn = {0161-8105}, author = {Redline, S and Sanders, M H and Lind, B K and Quan, S F and Iber, C and Gottlieb, D J and Bonekat, W H and Rapoport, D M and Smith, P L and Kiley, J P} } @article {609, title = {Effects of varying approaches for identifying respiratory disturbances on sleep apnea assessment.}, journal = {Am J Respir Crit Care Med}, volume = {161}, year = {2000}, month = {2000 Feb}, pages = {369-74}, abstract = {

Varying approaches to measuring the respiratory disturbance index (RDI) may lead to discrepant estimates of the severity of sleep-disordered breathing (SDB). In this study, we assessed the impact of varying the use of corroborative data (presence and degree of desaturation and/or arousal) to identify hypopneas and apneas. The relationships among 10 RDIs defined by various definitions of apneas and hypopneas were assessed in 5,046 participants in the Sleep Heart Health Study (SHHS) who underwent overnight unattended 12-channel polysomnography (PSG). The magnitude of the median RDI varied 10-fold (i.e., 29.3 when the RDI was based on events identified on the basis of flow or volume amplitude criteria alone to 2.0 for an RDI that required an associated 5\% desaturation with events). The correlation between RDIs based on different definitions ranged from 0.99 to 0.68. The highest correlations were among RDIs that required apneas and hypopneas to be associated with some level of desaturation. Lower correlations were observed between RDIs that required desaturation as compared with RDIs defined on the basis of amplitude criteria alone or associated arousal. These data suggest that different approaches for measuring the RDI may contribute to substantial variability in identification and classification of the disorder.

}, keywords = {Adult, Aged, Aged, 80 and over, Arousal, Diagnosis, Differential, Female, Humans, Lung Volume Measurements, Male, Middle Aged, Observer Variation, Oxygen, Oxyhemoglobins, Polysomnography, Risk Factors, Sleep Apnea Syndromes}, issn = {1073-449X}, doi = {10.1164/ajrccm.161.2.9904031}, author = {Redline, S and Kapur, V K and Sanders, M H and Quan, S F and Gottlieb, D J and Rapoport, D M and Bonekat, W H and Smith, P L and Kiley, J P and Iber, C} } @article {620, title = {Rates of sensor loss in unattended home polysomnography: the influence of age, gender, obesity, and sleep-disordered breathing.}, journal = {Sleep}, volume = {23}, year = {2000}, month = {2000 Aug 01}, pages = {682-8}, abstract = {

OBJECTIVES: To evaluate study failure and sensor loss in unattended home polysomnography and their relationship to age, gender, obesity, and severity of sleep-disordered breathing (SDB).

DESIGN: A cross-sectional analysis of data gathered prospectively for the Sleep Heart Health Study (SHHS).

SETTING: Unattended polysomnography was performed in participants{\textquoteright} homes by the staff of the sites that are involved in SHHS.

PARTICIPANTS: 6,802 individuals who met the inclusion criteria (age >40 years, no history of treatment of sleep apnea, no tracheostomy, no current home oxygen therapy) for SHHS.

RESULTS: A total of 6802 participants had 7151 studies performed. 6161 of 6802 initial studies (90.6\%) were acceptable. Obesity was associated with a decreased likelihood of a successful initial study. After one or more attempts, 6440 participants (94.7\%) had studies that were judged as acceptable. The mean duration of scorable signals for specific channels ranged from 5.7 to 6.8 hours. The magnitudes of the effects of age, gender, BMI, and RDI on specific signal durations were not clinically significant.

CONCLUSION: Unattended home PSG as performed for SHHS was usually successful. Participant characteristics had very weak associations with duration of scorable signal. This study suggests that unattended home PSG, when performed with proper protocols and quality controls, has reasonable success rates and signal quality for the evaluation of SDB in clinical and research settings.

}, keywords = {Age Factors, Cross-Sectional Studies, Electroencephalography, Electromyography, Electrooculography, Equipment Failure, Female, Humans, Male, Middle Aged, Obesity, Polysomnography, Prospective Studies, Severity of Illness Index, Sex Factors, Sleep Apnea Syndromes}, issn = {0161-8105}, author = {Kapur, V K and Rapoport, D M and Sanders, M H and Enright, P and Hill, J and Iber, C and Romaniuk, J} }