Correlates of QT prolongation in older adults (the Cardiovascular Health Study). Cardiovascular Health Study Collaborative Research Group.
Explore the source record for details and available documents.
Aged↗
Biomedical subjects
N O Borhani
Publications and source records attributed to N O Borhani.
Cardiac arrhythmias on 24-h ambulatory electrocardiography in older women and men: the Cardiovascular Health Study.
OBJECTIVES: This study describes the prevalence and correlates of cardiac arrhythmias in older persons. BACKGROUND: Cardiac arrhythmias are frequent in selected samples of elderly persons, but their prevalence and association with cardiovascular disease and its risk factors have not been examined in a large population-based sample. METHODS: In 1,372 participants in the Cardiovascular Health Study, a population-based study of cardiovascular disease risk factors, 24-h ambulatory electrocardiography was performed. RESULTS: Serious arrhythmias, such as sustained ventricular tachycardia and complete atrioventricular block, were uncommon, but brief episodes of ventricular tachycardia (> or = 3 consecutive ventricular depolarizations) were detected in 4.3% of women and 10.3% of men. Ventricular arrhythmias as a group (excluding ectopic beats < 15/h) were more common in men than in women but were not significantly associated with age. The same patterns were true for bradycardia/conduction blocks. Supraventricular arrhythmias as a group (excluding ectopic beats < 15/h), in contrast, did not differ by gender but were strongly associated with increased age. Multivariate analyses showed associations with arrhythmias to differ by gender, with only one association (increased age and supraventricular arrhythmias) present in both women and men. Ventricular arrhythmias, particularly in men, were associated with a higher prevalence of cardiovascular disease and its risk factors and with subclinical disease, as measured by increased left ventricular mass and impaired left ventricular function. CONCLUSIONS: Arrhythmias are common in the elderly, and their association with cardiovascular disease differs by gender. Although risk related to arrhythmias can only be determined by prospective study, such studies should have adequate power to examine potential gender differences in associations.
Aged↗
Correlates of blood pressure in community-dwelling older adults. The Cardiovascular Health Study. Cardiovascular Health Study (CHS) Collaborative Research Group.
Although elevated blood pressure is an important predictor of cardiovascular disease and stroke in the elderly, little information exists on the distribution and risk factor correlates of blood pressure in this group. As part of the Cardiovascular Health Study, a population-based cohort study of 5201 men and women aged 65 to 101 years, we investigated correlates of systolic and diastolic blood pressure. Multiple regression analyses were conducted for all participants and a subgroup of 2482 without coronary heart disease and not on antihypertensive therapy (the "healthier" subgroup). In the total group, independent predictors of diastolic blood pressure included heart rate, aortic root dimension, creatinine, hematocrit, alcohol use, and black race (positive associations) and internal carotid artery wall thickness, mitral early/late peak flow velocity, white blood cell count, cigarette smoking, and age (negative associations). Positive predictors of systolic blood pressure included mitral late peak flow velocity, left ventricular mass, common carotid artery wall thickness, serum albumin, factor VII, diabetes, alcohol use, and age; negative predictors were coronary heart disease, uric acid, height, and smoking. In the healthier subgroup, positive predictors of diastolic blood pressure included heart rate, hematocrit, serum albumin, creatinine, and body weight, whereas mitral early/late peak flow velocity, serum potassium, smoking, and age inversely related to diastolic pressure. For the same group, common carotid artery wall thickness, left ventricular mass, serum albumin, factor VII, high-density lipoprotein cholesterol, and age were directly related to systolic blood pressure, whereas serum potassium was inversely related. Both systolic and diastolic pressures varied considerably by geographic site.(ABSTRACT TRUNCATED AT 250 WORDS)
Aged↗
The effect of fish oil on blood pressure and high-density lipoprotein-cholesterol levels in phase I of the Trials of Hypertension Prevention. Trials of Hypertension Prevention Collaborative Research Group.
OBJECTIVE: To study the effects of moderate doses of fish oil on blood pressure and high-density lipoprotein (HDL)-cholesterol. METHODS: The participants were 350 normotensive men and women aged 30-54 years who were enrolled from seven academic medical centers in phase I of the Trials of Hypertension Prevention. They were randomly assigned to receive placebo or 6 g purified fish oil once a day, which supplied 3 g n-3 polyunsaturated fatty acids for 6 months. RESULTS: Baseline blood pressure was (mean +/- SD) 123 +/- 9/81 +/- 5 mmHg. The mean differences in the blood pressure changes between the fish oil and placebo groups were not statistically significant. There was no tendency for fish oil to reduce blood pressure more in subjects with baseline blood pressures in the upper versus the lower quartile (132/87 versus 114/75 mmHg), low habitual fish consumption (0.4 versus 2.9 times a week) or low baseline plasma levels of n-3 fatty acids. Fish oil increased HDL2-cholesterol significantly compared with the placebo group. Subgroup analysis showed this effect to be significant in the women but not in the men. Increases in serum phospholipid n-3 fatty acids were significantly correlated with increases in HDL2-cholesterol and decreases in systolic blood pressure. CONCLUSION: Moderate amounts of fish oil (6 g/day) are unlikely to lower blood pressure in normotensive persons, but may increase HDL2-cholesterol, particularly in women.
Adult↗
Hypertension and atherosclerosis. Therapeutic perspectives.
Explore the source record for details and available documents.
Arteriosclerosis↗
Risk management in stroke prevention: major clinical trials in hypertension.
Results of all major clinical trials on the efficacy of treatment of hypertension provide convincing evidence that judicious treatment of hypertension in a clinical setting and effective control of hypertension in a community setting significantly reduce the rate of morbidity and mortality from stroke. It is especially noteworthy to review the results of some of the trials on prevention of stroke mortality in the elderly. HDFP: Antihypertensive drug treatment reduced the incidence of stroke among the HDFP cohort in the age group 60-69 years as significantly as it did in the younger age group. SHEP: Treatment of isolated systolic hypertension (ISH) reduced the incidence of stroke in the SHEP cohort by 36% in five years. MRC Trial: Similar results were reported by the follow-up of the cohort enrolled in the MRC Trial. The Swedish Study: Antihypertensive treatment reduced significantly the incidence of stroke in this cohort as well.
Aged↗
Short report: the effect of fish oil on blood pressure and high-density lipoprotein-cholesterol levels in phase I of the Trials of Hypertension Prevention.
OBJECTIVE: To study the effects of moderate doses of fish oil on blood pressure and high-density lipoprotein (HDL)-cholesterol. METHODS: The participants were 350 normotensive men and women aged 30-54 years who were enrolled from seven academic medical centers in phase I of the Trials of Hypertension Prevention. They were randomly assigned to receive placebo or 6 g purified fish oil once a day, which supplied 3 g n-3 polyunsaturated fatty acids for 6 months. RESULTS: Baseline blood pressure was (mean +/- SD) 123 +/- 9/81 +/- 5 mmHg. The mean differences in the blood pressure changes between the fish oil and placebo groups were not statistically significant. There was no tendency for fish oil to reduce blood pressure more in subjects with baseline blood pressure in the upper versus the lower quartile (132/87 versus 114/75 mmHg), low habitual fish consumption (0.4 versus 2.9 times a week) or low baseline plasma levels of n-3 fatty acids. Fish oil increased HDL2-cholesterol significantly compared with the placebo group. Subgroup analysis showed this effect to be significant in the women but not in the men. Increases in serum phospholipid n-3 fatty acids were significantly correlated with increases in HDL2-cholesterol and decreases in systolic blood pressure. CONCLUSION: Moderate amounts of fish oil (6 g/day) are unlikely to lower blood pressure in normotensive persons, but may increase HDL2-cholesterol, particularly in women.
Adult↗
MIDAS: rationale, design and descriptive data of trial patients. The MIDAS Research Group.
Certain classes of antihypertensive drugs, such as calcium antagonists, appear to have antiatherogenic properties, as shown in animal models. In these experimental models, only isradipine, a potent new dihydropyridine calcium antagonist, has shown an antiatherogenic effect in doses compatible with that recommended for antihypertensive treatment in humans. The Multicenter Isradipine/Diuretic Atherosclerosis Study (MIDAS) was designed to assess the efficacy of isradipine (2.5 or 5.0 mg twice daily) compared with hydrochlorothiazide (HCTZ) in reducing the rate of progression of atherosclerotic plaque in carotid arteries, as measured by B-mode ultrasonography. MIDAS is the first clinical trial of hypertension designed to test the hypothesis that antihypertensive drug treatment may have a favourable effect on the progression of atherosclerosis in humans. MIDAS is a double-blind, randomized, controlled clinical trial involving 883 patients. The primary endpoint is the observed change in the rate of progression of the intimal-medial wall thickness of the carotid arteries, as measured quantitatively by B-mode ultrasonography over time. Changes in the mean maximum intimal-medial thickness (IMT) at 12 points in the carotid arteries (near and far walls of the common carotid, the carotid bifurcation, and internal carotid segments on both right and left sides of the neck) were measured over a 3-year period. At baseline, the mean age of the participants was 58.5 years. The mean systolic and diastolic blood pressures were, respectively, 149.8 and 96.5 mmHg. The mean duration of hypertension was 10 years.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Prevalence of cardiovascular diseases among older adults. The Cardiovascular Health Study.
The Cardiovascular Health Study is a population-based longitudinal study of 5,201 adults aged 65 years and older. Prevalences of myocardial infarction, angina pectoris, congestive heart failure, peripheral artery disease, stroke, and transient ischemic attack were ascertained between June 1989 and May 1990 in participants recruited from Forsyth County, North Carolina; Washington County, Maryland; Sacramento County, California; and Pittsburgh, Pennsylvania. A medical history was taken to obtain self-reports of prevalent disease. For all participants, use of nitrates was ascertained to document angina, electrocardiograms were used to document prevalent myocardial infarction, and ankle-arm blood pressure studies were used to document peripheral artery disease. Self-reports of disease that were not confirmed by examination findings were further investigated by examination of medical records. Reported disease that was confirmed by examination findings or by medical records was classified as "definite." Disease that was documented by examination, but not reported by the participant, was classified as "unreported." The prevalence rates of definite myocardial infarction and angina were 11% and 15%, respectively, among men aged 65-69 years, 18% and 17% among men aged 80-84 years, 4% and 8% among women aged 65-69 years, and 3% and 13% among women aged 80-84 years. Twenty-three percent of men and 38% of women with electrocardiographic evidence of myocardial infarction did not report it. These results suggest that prevalent disease estimates based only on self-report may underestimate the prevalence of cardiovascular diseases in older Americans.
Age Factors↗
Recruitment of adults 65 years and older as participants in the Cardiovascular Health Study.
Few large-scale epidemiologic studies have enrolled older adults; hence, little is known about the feasibility of recruiting this group for long-term population-based studies. In this article we present the recruitment experience of the Cardiovascular Health Study (CHS), a population-based, longitudinal study of cardiovascular diseases in adults 65 years and older. Participants were sampled from the Health Care Financing Administration's (HCFA) Medicare eligibility lists in four US communities. Letters were mailed to 11,955 sampled individuals. Persons recruited were required to complete an extensive home interview and then a 4-hour in-clinic examination. Excluded were persons who were expected to be able to complete the baseline examination and who were not expected to return for the 3-year follow-up. Some 3654 participants were recruited from those randomly selected from the Medicare sampling frame. In addition, 1547 other age-eligible persons living in the household with the sampled individuals also participated, yielding a total of 5201 participants. Of those who were contacted, 9.6% were ineligible and 34.9% refused participation. Among those eligible, 38.6% refused and 57.3% were enrolled (the remaining did not refuse but were not enrolled before the recruitment ended). Data from a subsample indicate that compared to those who were ineligible or who refused, enrolled participants were younger, more highly educated, more likely to be married, and less likely to report limitations in activity. Compared to those who were eligible but refused, enrolled participants were less likely to have high blood pressure and stroke and more likely to have quit smoking and to perceive their health status as very good or excellent.(ABSTRACT TRUNCATED AT 250 WORDS)
Aged↗
Calcium antagonists and atherosclerosis. The Multicenter Isradipine/Diuretic Atherosclerosis Study.
The Multicenter Isradipine/Diuretic Atherosclerosis Study (MIDAS) is a double-blind, randomized, controlled clinical trial comparing the effects of isradipine and hydrochlorothiazide on the progression or regression of early carotid atherosclerosis in 883 hypertensive patients. Assessment of the outcome is by B-mode ultrasonographic measurement of early lesions (as reflected by intimal-medial wall thickening) at baseline and semiannually over 36 months. At baseline, the participants' mean age was 58.5 years. The study population was 78.6% male and 72.4% white. The average resting systolic and diastolic blood pressures were 149.8 and 96.5 mm Hg, respectively. Mean total serum cholesterol and low-density lipoprotein (LDL)-cholesterol levels were 216.2 mg/dL and 146.6 mg/dL, respectively. Risk factors for coronary artery disease were balanced at baseline between the two study groups. The mean maximum intimal-medial thickness at baseline (measured in the near and far walls of three segments for both carotid arteries) was 1.17 +/- 0.20 mm; the mean intimal-medial thickness of the single thickest lesion was 2.11 +/- 0.51 mm. Cross-sectional analyses show that intimal-medial thickness correlates independently with male gender, age, number of cigarettes smoked per day, levels of LDL cholesterol, systolic blood pressure, and white blood cell count. The MIDAS endpoint results will be available in 1993.
Adult↗
Epidemiology of low cholesterol levels in older adults. The Cardiovascular Health Study.
BACKGROUND: Low cholesterol levels have been associated with increased mortality from stroke, cancer, and other noncardiovascular diseases, but the reasons for this association remain unclear. One explanation is that persons with low cholesterol levels have early or occult disease that eventually leads to their deaths. METHODS AND RESULTS: This possibility was explored in 2,091 men and 2,714 women 65-100 years old in the Cardiovascular Health Study, a multicenter observational study of risk factors for heart disease and stroke in older adults. Cholesterol levels < or = 160 mg/dL were present in 11.6% of men and 3.7% of women and increased in prevalence with age. After adjustment for age, total cholesterol levels in this range were associated with a twofold increased prevalence of treated diabetes in men and women and with a twofold increased prevalence of cancer diagnosed in the preceding 5 years in women only. Low cholesterol was also associated with lower levels of hemoglobin, albumin, and factor VII, suggesting a link with hepatic synthetic function. On multivariate analysis, factors most strongly associated with low cholesterol levels in men and women were decreased factor VII levels, decreased albumin, and diabetes. CONCLUSIONS: Cross-sectional associations with low cholesterol levels differ by sex and suggest poorer health by some measures. The observed relations with treated diabetes and impaired hepatic synthetic function should be examined for risk of mortality in longitudinal data from this and other observational studies.
Aged↗
Ankle-arm index as a marker of atherosclerosis in the Cardiovascular Health Study. Cardiovascular Heart Study (CHS) Collaborative Research Group.
BACKGROUND: Peripheral arterial disease measured noninvasively by the ankle-arm index (AAI) is common in older adults, largely asymptomatic, and associated with clinically manifest cardiovascular disease (CVD). The criteria for an abnormal AAI have varied in previous studies. To determine whether there is an inverse dose-response relation between the AAI and clinical CVD, subclinical disease, and risk factors, we examined the relation of the AAI to cardiovascular risk factors, other noninvasive measures of subclinical atherosclerosis using carotid ultrasound, echocardiography and electrocardiography, and clinical CVD. METHODS AND RESULTS: The AAI was measured in 5084 participants > or = 65 years old at the baseline examination of the Cardiovascular Health Study. All subjects had detailed assessment of prevalent CVD, measures of cardiovascular risk factors, and noninvasive measures of disease. Participants were stratified by baseline clinical CVD status and AAI (< 0.8, > or = 0.8 to < 0.9, > or = 0.9 to < 1.0, > or = 1.0 to < 1.5). Analyses tested for a dose-response relation of the AAI with clinical CVD, risk factors, and subclinical disease. The cumulative frequency of a low AAI was 7.4% of participants < 0.8, 12.4% < 0.9, and 23.6% < 1.0. participants with an AAI < 0.8 were more than twice as likely as those with an AAI of 1.0 to 1.5 to have a history of myocardial infarction, angina, congestive heart failure, stroke, or transient ischemic attack (all P < .01). In participants free of clinical CVD at baseline, the AAI was inversely related to history of hypertension, history of diabetes, and smoking, as well as systolic blood pressure, serum creatinine, fasting glucose, fasting insulin, measures of pulmonary function, and fibrinogen level (all P < .01). Risk factor associations with the AAI were similar in men and women free of CVD except for serum total and low-density lipoprotein cholesterol, which were inversely associated with AAI level only in women. Risk factors associated with an AAI of < 1.0 in multivariate analysis included smoking (odds ratio [OR], 2.55), history of diabetes (OR, 3.84), increasing age (OR, 1.54), and nonwhite race (OR, 2.36). In the 3372 participants free of clinical CVD, other noninvasive measures of subclinical CVD, including carotid stenosis by duplex scanning, segmental wall motion abnormalities by echocardiogram, and major ECG abnormalities were inversely related to the AAI (all P < .01). CONCLUSIONS: There was an inverse dose-response relation of the AAI with CVD risk factors and subclinical and clinical CVD among older adults. The lower the AAI, the greater the increase in CVD risk; however, even those with modest, asymptomatic reductions in the AAI (0.8 to 1.0) appear to be at increased risk of CVD.
Aged↗
Properties of the random zero sphygmomanometer.
The random zero sphygmomanometer is widely used in studies involving blood pressure measurement because it is believed to eliminate digit preference and reduce measurement error. We performed blood pressure measurements sequentially using random zero and standard sphygmomanometers in random order in 1,356 participants in the Cardiovascular Health Study. Despite adherence to the manufacturer's instructions, we observed a substantially nonuniform distribution of zero levels generated by the random zero sphygmomanometer and a disturbing correlation between the zero level and blood pressures taken with the standard sphygmomanometer. With the random zero device, the pooled estimated slopes for the regression of standard systolic and diastolic pressures on the zero level were -0.71 and -0.17, respectively (both p < 0.0001). The only plausible explanation for this relation between the random zero device and the standard device is that by some unknown mechanism the subject's blood pressure is influencing the zero level. Systolic and diastolic blood pressures measured with the random zero device were, respectively, 1.65 and 1.84 mm Hg lower (both p < 0.0001) than standard blood pressures. Digit preference was detectable in the uncorrected blood pressure and zero level measured with the random zero device but was eliminated after calculation of the corrected blood pressure. For most epidemiological studies, the random zero sphygmomanometer offers no significant advantage over the standard sphygmomanometer. It may still be useful in those epidemiological studies and clinical trials where blinding is important.
Aged↗
Isolated systolic hypertension and subclinical cardiovascular disease in the elderly. Initial findings from the Cardiovascular Health Study.
OBJECTIVE: To assess the association between isolated systolic hypertension (ISH) and subclinical disease in adults aged 65 years and above. DESIGN: Medicare eligibility lists were used to obtain a representative sample of 5201 community-dwelling elderly persons for the Cardiovascular Health Study, a National Heart, Lung, and Blood Institute--sponsored cohort study of risk factors for coronary heart disease and stroke. In this cross-sectional analysis of baseline data, we excluded 3012 participants who were receiving antihypertensive medications, had clinical cardiovascular disease, or had a diastolic blood pressure of at least 90 mm Hg. MAIN OUTCOME MEASURES: For electrocardiogram: myocardial infarction, left ventricular hypertrophy, and left ventricular mass as measures of myocardial damage and strain; for echocardiography: left ventricular mass, fractional shortening, and Doppler flow velocities as measures of cardiac systolic and diastolic function; and for carotid sonography: carotid arterial intima-media thickness as a measure of atherosclerosis. RESULTS: Among the 2189 men and women in this analysis, 195 (9%) had ISH (systolic blood pressure, greater than or equal to 160 mm Hg) and 596 (23%) had borderline ISH (systolic blood pressure, 140 to 159 mm Hg). Systolic blood pressure was associated with myocardial infarction by electrocardiogram (P = .02). Borderline and definite ISH were strongly associated with left ventricular mass (P less than .001). While there was little association with cardiac systolic function, borderline and definite ISH were associated with cardiac diastolic function (P less than .001). Isolated systolic hypertension was also strongly associated with increased intima-media thickness of the carotid artery (P less than .001). CONCLUSIONS: While cohort analyses of future repeated measures will provide a better assessment of risk, both borderline and definite ISH were strongly related to a variety of measures of subclinical disease in elderly men and women.
Aged↗
Major electrocardiographic abnormalities in persons aged 65 years and older (the Cardiovascular Health Study). Cardiovascular Health Study Collaborative Research Group.
Electrocardiographic abnormalities are often found in older patients, but their prevalence in free-living elderly populations is not well-defined. In addition, the clinical significance of many of these abnormalities is uncertain. The prevalence of major electrocardiographic abnormalities was determined in 5,150 adults aged greater than or equal to 65 years from the Cardiovascular Health Study--a study of risk factors for stroke and coronary heart disease in the elderly. Ventricular conduction defects, major Q/QS waves, left ventricular hypertrophy, isolated major ST-T-wave abnormalities, atrial fibrillation and first-degree atrioventricular block were collectively categorized as major electrocardiographic abnormalities. Prevalence of any major electrocardiographic abnormality was 29% in the entire cohort, 19% among 2,413 participants who reported no history of coronary artery disease or systemic hypertension, and 37% among 2,737 participants with a history of coronary artery disease or hypertension. Prevalence of major electrocardiographic abnormalities was higher in men than in women regardless of history, and tended to increase with age. Major Q/QS waves were found in 5.2%, and more than half were in those who did not report a previous myocardial infarction. Major electrocardiographic abnormalities are common in elderly men and women irrespective of the history of heart disease.
Age Factors↗
Eligibility for cholesterol referral in community-dwelling older adults. The Cardiovascular Health Study.
OBJECTIVES: To assess the proportion of community-dwelling adults aged 65 years or older who are eligible for referral for lipoprotein analysis and intervention according to the National Cholesterol Education Program (NCEP) guidelines. DESIGN: Cross-sectional study based on examinations and questionnaires collected in 1989 and 1990. SETTING: Four communities in the U.S. in the Cardiovascular Health Study (CHS), a study of risk factors for heart disease and stroke in older adults. PARTICIPANTS: A sample of 4810 men and women ages 65 to 100 randomly selected and recruited from Health Care Financing Administration Medicare eligibility lists for the four communities; not institutionalized, not wheelchair-bound, not currently receiving therapy for cancer, not currently taking lipid-lowering medications, and not having eaten in the preceding 9 hours. MEASUREMENTS: Total cholesterol and lipoprotein analysis measured in all participants. RESULTS: Total cholesterol levels were less than 5.17 mmol/L (200 mg/dL) in 37% of participants, 5.17 to 6.19 mmol/L (200 to 239 mg/dL) in 39%, and 6.20 mmol/L (240 mg/dL) or greater in 24%. Compared with their counterparts, older participants, especially those over 80 years of age, were more likely to have levels below 5.17 mmol/L, as were men, nonwhites, and those with coronary heart disease or two or more coronary heart disease risk factors (P less than 0.008 for all values). Based on this screening measurement, 2174 participants were eligible for lipoprotein analysis, 80% were eligible for dietary or drug therapy using NCEP guidelines. Overall, 46% of CHS participants were eligible for lipoprotein analysis and 36% for intervention by NCEP guidelines, based on a single cholesterol measurement. CONCLUSION: A substantial proportion of older adults in this community sample were eligible for lipoprotein analysis and intervention. Prospective studies of elderly persons are needed to determine the risk for incident coronary heart disease according to NCEP classifications and the benefits of lipid-lowering treatments in persons in this age group so that intervention strategies may best be targeted to an appropriately high-risk group.
Age Factors↗
Frequency of ventricular ectopic activity in isolated systolic systemic hypertension.
Explore the source record for details and available documents.
Aged↗