@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 = {<p>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.</p>},
	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 {662,
	title = {Echocardiographic features of the right heart in sleep-disordered breathing: the Framingham Heart Study.},
	journal = {Am J Respir Crit Care Med},
	volume = {164},
	year = {2001},
	month = {2001 Sep 15},
	pages = {933-8},
	abstract = {<p>The effect of sleep-disordered breathing (SDB) on right heart structure and function is controversial. Studies of patients referred for evaluation of possible sleep apnea have yielded conflicting results, and the impact of SDB on the right heart has not been investigated in the general population. We examined the echocardiographic features of subjects with SDB at the Framingham Heart Study site of the Sleep Heart Health Study. Of 1,001 polysomnography subjects, 90 with SDB defined as a respiratory disturbance index (RDI) score > 90th percentile (mean RDI = 42) were compared with 90 low-RDI subjects (mean RDI = 5) matched for age, sex, and body mass index. Right heart measurements, made without knowledge of clinical status, were compared between groups. The majority of the subjects were male (74\%). After multivariable adjustment, right ventricle (RV) wall thickness was significantly greater (p = 0.005) in subjects with SDB (0.78 +/- 0.02 cm) than in the low-RDI subjects (0.68 +/- 0.02 cm). Right atrial dimensions, RV dimensions, and RV systolic function were not found to be significantly different between subjects with SDB and the low-RDI subjects. We conclude that in this community-based study of SDB and right heart echocardiographic features, RV wall thickness was increased in subjects with SDB. Whether the RV hypertrophy observed in persons with SDB is associated with increased morbidity and mortality remains unknown.</p>},
	keywords = {Adult, Age Factors, Aged, Cohort Studies, Cross-Sectional Studies, Data Interpretation, Statistical, Echocardiography, Female, Forced Expiratory Volume, Humans, Hypertrophy, Right Ventricular, Linear Models, Male, Middle Aged, Obesity, Observer Variation, Polysomnography, Prospective Studies, Sex Factors, Sleep Apnea Syndromes, Ventricular Function, Right, Vital Capacity},
	issn = {1073-449X},
	doi = {10.1164/ajrccm.164.6.2001092},
	author = {Guidry, U C and Mendes, L A and Evans, J C and Levy, D and O{\textquoteright}Connor, G T and Larson, M G and Gottlieb, D J and Benjamin, E J}
}
