@article {1420, title = {A method for using MR to evaluate the effects of cardiovascular disease on the brain: the cardiovascular health study.}, journal = {AJNR Am J Neuroradiol}, volume = {15}, year = {1994}, month = {1994 Oct}, pages = {1625-33}, abstract = {

PURPOSE: To do a pilot study for the Cardiovascular Health Study (a population-based, longitudinal study of coronary heart disease and stroke in adults 65 years of age and older designed to identify risk factors related to cerebrovascular disease, particularly stroke): (a) to determine the feasibility of adding brain MR to the full-scale study; (b) to evaluate the reliability of standardized MR image interpretation in a multicenter study; and (c) to compare the prevalence of stroke determined by MR with that by clinical history.

METHODS: Protocol-defined MR studies were performed in 100 subjects with clinical histories of stroke and 203 subjects without reported histories of stroke. MR scans were independently evaluated by two trained neuroradiologists for the presence of small (< or = 3 mm) and large (> 3 mm) "infarctlike" lesions. The sizes of the cerebral sulci and lateral ventricles and the extent of white matter disease were graded on a scale of 0 to 9.

RESULTS: Eighty percent of the Cardiovascular Health Study participants who were invited to undergo MR studies agreed to do so; 95\% of those agreeing to the procedure successfully completed the exams. Intrareader and interreader reliability of infarctlike lesion identification was high for large lesions (kappa, 0.71 and 0.78, respectively) but not for small lesions (kappa, 0.71 and 0.32, respectively). Relaxed intrareader and interreader kappa scores for sulcal and ventricular sizes and extent of white matter disease were greater than 0.8 MR evidence of infarctlike lesions was present in 77\% of the participants with histories of stroke but was also present in 23\% of the participants without clinical histories of stroke. Seventy-nine percent of the infarctlike lesions were larger than 3 mm.

CONCLUSIONS: This preliminary study indicates that a large, prospective, epidemiologic study of elderly subjects using MR scans of the brain for identification of cerebrovascular disease is feasible and that the interpretative results are reproducible, and suggests that MR evidence of stroke is more prevalent than reported clinical history of stroke.

}, keywords = {Aged, Brain, Cerebral Infarction, Cerebral Ventricles, Cerebrovascular Disorders, Cohort Studies, Coronary Disease, Cross-Sectional Studies, Diagnosis, Differential, Feasibility Studies, Female, Humans, Image Interpretation, Computer-Assisted, Incidence, Longitudinal Studies, Magnetic Resonance Imaging, Male, Mass Screening, Observer Variation, Pilot Projects, Prospective Studies, Risk Factors, United States}, issn = {0195-6108}, author = {Bryan, R N and Manolio, T A and Schertz, L D and Jungreis, C and Poirier, V C and Elster, A D and Kronmal, R A} } @article {1424, title = {Self-reported causes of physical disability in older people: the Cardiovascular Health Study. CHS Collaborative Research Group.}, journal = {J Am Geriatr Soc}, volume = {42}, year = {1994}, month = {1994 Oct}, pages = {1035-44}, abstract = {

OBJECTIVE: To determine the major conditions and symptoms reported to cause difficulty in 17 physical tasks of daily life and the criterion validity of self-report of diseases given as the causes of the difficulty in functioning, in community-dwelling older people.

DESIGN: Cross sectional analyses of data obtained in an observational cohort study.

SETTING: Research clinics in four US communities: Winston-Salem, NC, Hagerstown, MD, Pittsburgh, PA, and Sacramento, CA.

PARTICIPANTS: 5201 community-dwelling people > or = 65 years old.

RESULTS: Arthritis and other musculoskeletal diseases were given as the primary causes of difficulty in performing physical tasks by 49.0\% of the participants reporting difficulty in any task, followed by heart disease (13.7\%), injury (12.0\%), old age (11.7\%), lung disease (6.0\%), and stroke (2.9\%). The self-reports of diseases that caused disability varied by task. Whereas arthritis was given as a cause of difficulty in most of the 17 different tasks, heart and lung disease were more likely to be reported as causing difficulty with activities requiring high aerobic work capacity such as walking one-half mile or doing heavy housework. Stroke was more likely to be reported as causing difficulty with use of the upper extremities and in performing basic activities of daily living. There was a high degree of consistency (91\%) between the diseases and symptoms reported to cause disabilities. The percentage of people who reported a disease as the cause of their difficulty performing a task and had independent confirmation of the diagnosis was 85\% in men and 71\% in women, and varied according to type of disease and the individual{\textquoteright}s cognitive status and health status.

CONCLUSION: These data suggest that age-related chronic diseases are important causes of disability in older people but that the type of disability is dependent on the underlying disease that causes the disability. Also, self-report of the cause of disability appears to be generally accurate but is influenced by gender, health status, and type of disease.

}, keywords = {Activities of Daily Living, Aged, Aged, 80 and over, Arthritis, Cardiovascular Diseases, Chronic Disease, Cohort Studies, Cross-Sectional Studies, Disabled Persons, Female, Health Status, Health Surveys, Heart Diseases, Humans, Lung Diseases, Male, Observer Variation, Reproducibility of Results, Risk Factors, Sex Factors, United States}, issn = {0002-8614}, author = {Ettinger, W H and Fried, L P and Harris, T and Shemanski, L and Schulz, R and Robbins, J} } @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 {665, title = {Brachial flow-mediated vasodilator responses in population-based research: methods, reproducibility and effects of age, gender and baseline diameter.}, journal = {J Cardiovasc Risk}, volume = {8}, year = {2001}, month = {2001 Oct}, pages = {319-28}, abstract = {

BACKGROUND: Brachial artery ultrasound has been proposed as an inexpensive, accurate way to assess cardiovascular risk in populations. However, analysis and interpretation of these data are not uniform.

METHODS: We analysed the relationship between relative and absolute changes in brachial artery diameter in response to flow-mediated dilation and age, gender and baseline diameter among 4,040 ultrasound examinations from subjects aged 14 to 98 years.

RESULTS: Reproducibility studies demonstrated intra- and interreader and intrasubject correlations from 0.67 to 0.84 for repeated measures of per cent change in diameter. Per cent change in diameter after flow stimulus was 3.58 +/- 0.10\% (mean +/- standard deviation). Corresponding values for baseline diameter and absolute change in diameter were 4.43 +/- 0.87 mm and 0.15 +/- 0.01 mm, respectively. Baseline diameter and its variance were inversely related to per cent change in diameter (P< 0.001). In contrast, absolute change in diameter was more uniform throughout the range of baseline diameters. Baseline diameter was directly related, and per cent change in diameter inversely related, to age (P < 0.001 for all three measures). Time to maximum vasodilator response increased with age (P < 0.001). Women (n=2,315) had significantly larger per cent change in diameter than men (n=1,725) (P < 0.001). However, after adjustment for age and baseline diameter, per cent and absolute change were 5\% smaller in women than men (P < 0.05 for both). In multivariate analysis, age was overwhelmingly the most important determinant of absolute change in diameter (P < 0.001).

CONCLUSIONS: Automated analysis of brachial flow-mediated vasodilator responses is both feasible and reproducible in large-scale clinical and population-based research.

}, keywords = {Adolescent, Adult, Age Factors, Aged, Aged, 80 and over, Blood Circulation, Brachial Artery, Female, Humans, Male, Middle Aged, Observer Variation, Population Surveillance, Reproducibility of Results, Sex Factors, Vasodilation, Vasodilator Agents}, issn = {1350-6277}, doi = {10.1177/174182670100800512}, author = {Herrington, D M and Fan, L and Drum, M and Riley, W A and Pusser, B E and Crouse, J R and Burke, G L and McBurnie, M A and Morgan, T M and Espeland, M A} } @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 = {

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.

}, 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} }