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C Furberg

Publications and source records attributed to C Furberg.

At least 19 recordsLinked to original sources

Postmenopausal hormone therapy increases risk for venous thromboembolic disease. The Heart and Estrogen/progestin Replacement Study.

BACKGROUND: Oral contraceptive use increases risk for venous thromboembolism, but data on the effect of postmenopausal hormone therapy are limited. OBJECTIVE: To determine the effect of therapy with estrogen plus progestin on risk for venous thromboembolic events in postmenopausal women. DESIGN: Randomized, double-blind, placebo-controlled trial. SETTING: 20 clinical centers in the United States. PARTICIPANTS: 2763 postmenopausal women younger than 80 years of age (mean age, 67 years) who had coronary heart disease but no previous venous thromboembolism and had not had a hysterectomy. INTERVENTION: Conjugated equine estrogens, 0.625 mg, plus medroxyprogesterone acetate, 2.5 mg, in one tablet (n = 1380) or placebo that was identical in appearance (n = 1383). MEASUREMENTS: Documented deep venous thrombosis or pulmonary embolism. RESULTS: During an average of 4.1 years of follow-up, 34 women in the hormone therapy group and 13 in the placebo group experienced venous thromboembolic events (relative hazard, 2.7 [95% CI, 1.4 to 5.0] [P = 0.003]; excess risk, 3.9 per 1000 woman-years [CI, 1.4 to 6.4 per 1000 woman-years]; number needed to treat for harm, 256 [CI, 157 to 692]). In multivariate analysis, the risk for venous thromboembolism was increased among women who had lower-extremity fractures (relative hazard, 18.1 [CI, 5.4 to 60.4]) or cancer (relative hazard, 3.9 [CI, 1.6 to 9.4]) and for 90 days after inpatient surgery (relative hazard, 4.9 [CI, 2.4 to 9.8]) or nonsurgical hospitalization (relative hazard, 5.7 [CI, 3.0 to 10.8]). Risk was decreased with aspirin (relative hazard, 0.5 [CI, 0.2 to 0.8]) or statin use (relative hazard, 0.5 [CI, 0.2 to 0.9]). CONCLUSIONS: Postmenopausal therapy with estrogen plus progestin increases risk for venous thromboembolism in women with coronary heart disease. This risk should be considered when the risks and benefits of therapy are being weighed.

Aged↗

Estrogen replacement therapy and MRI-demonstrated cerebral infarcts, white matter changes, and brain atrophy in older women: the Cardiovascular Health Study.

OBJECTIVE: We studied the relationship between the use of estrogen replacement therapy (ERT) and cerebral magnetic resonance imaging (MRI) abnormalities among older women. DESIGN: A population-based prospective study (Cardiovascular Health Study). SETTING: Four regions in the United States. PARTICIPANTS: A total of 2133 (62.9% of the eligible) women aged 65 to 95 years (mean age 74.8), on whom MRI was performed in 1992-1994. MEASUREMENTS: Presence of global brain atrophy, white matter changes, small infarct-like lesion (ILL) (<3 mm), MRI infarcts (> or =3 mm, mostly small and asymptomatic), and cognitive function as measured by Mini-Mental State Exam (MMSE), and by ERT use (current/past/never), adjusted for a number of socioeconomic, lifestyle, and reproductive covariates. RESULTS: Current use of ERT was reported by 15% and past use by another 23% of participants; 35% of all women had MRI infarcts. The prevalence of MRI infarcts did not differ in current or past users from those who had never used ERT (nonusers). Bifrontal distance, the largest distance between frontal horns, and the size of ventricles were larger among current ERT users compared to past users or nonusers (P (trend) = .01), adjusted for all other covariates, but no dose-response relationship to current or past ERT use was found. Duration of estrogen use was not associated with any atrophy measure. Cortical atrophy measure, sulcal widening, or white matter disease did not differ significantly by ERT use or duration of use. Central measures of atrophy, bifrontal distance, and ventricular size were significantly associated with cognition as measured by MMSE. CONCLUSIONS: Current ERT users had much more clinically significant central atrophy than nonusers, but the implications remained unclear.

Aged↗

Randomized trial of estrogen plus progestin for secondary prevention of coronary heart disease in postmenopausal women. Heart and Estrogen/progestin Replacement Study (HERS) Research Group.

CONTEXT: Observational studies have found lower rates of coronary heart disease (CHD) in postmenopausal women who take estrogen than in women who do not, but this potential benefit has not been confirmed in clinical trials. OBJECTIVE: To determine if estrogen plus progestin therapy alters the risk for CHD events in postmenopausal women with established coronary disease. DESIGN: Randomized, blinded, placebo-controlled secondary prevention trial. SETTING: Outpatient and community settings at 20 US clinical centers. PARTICIPANTS: A total of 2763 women with coronary disease, younger than 80 years, and postmenopausal with an intact uterus. Mean age was 66.7 years. INTERVENTION: Either 0.625 mg of conjugated equine estrogens plus 2.5 mg of medroxyprogesterone acetate in 1 tablet daily (n = 1380) or a placebo of identical appearance (n = 1383). Follow-up averaged 4.1 years; 82% of those assigned to hormone treatment were taking it at the end of 1 year, and 75% at the end of 3 years. MAIN OUTCOME MEASURES: The primary outcome was the occurrence of nonfatal myocardial infarction (MI) or CHD death. Secondary cardiovascular outcomes included coronary revascularization, unstable angina, congestive heart failure, resuscitated cardiac arrest, stroke or transient ischemic attack, and peripheral arterial disease. All-cause mortality was also considered. RESULTS: Overall, there were no significant differences between groups in the primary outcome or in any of the secondary cardiovascular outcomes: 172 women in the hormone group and 176 women in the placebo group had MI or CHD death (relative hazard [RH], 0.99; 95% confidence interval [CI], 0.80-1.22). The lack of an overall effect occurred despite a net 11% lower low-density lipoprotein cholesterol level and 10% higher high-density lipoprotein cholesterol level in the hormone group compared with the placebo group (each P<.001). Within the overall null effect, there was a statistically significant time trend, with more CHD events in the hormone group than in the placebo group in year 1 and fewer in years 4 and 5. More women in the hormone group than in the placebo group experienced venous thromboembolic events (34 vs 12; RH, 2.89; 95% CI, 1.50-5.58) and gallbladder disease (84 vs 62; RH, 1.38; 95% CI, 1.00-1.92). There were no significant differences in several other end points for which power was limited, including fracture, cancer, and total mortality (131 vs 123 deaths; RH, 1.08; 95% CI, 0.84-1.38). CONCLUSIONS: During an average follow-up of 4.1 years, treatment with oral conjugated equine estrogen plus medroxyprogesterone acetate did not reduce the overall rate of CHD events in postmenopausal women with established coronary disease. The treatment did increase the rate of thromboembolic events and gallbladder disease. Based on the finding of no overall cardiovascular benefit and a pattern of early increase in risk of CHD events, we do not recommend starting this treatment for the purpose of secondary prevention of CHD. However, given the favorable pattern of CHD events after several years of therapy, it could be appropriate for women already receiving this treatment to continue.

Aged↗

Heart and Estrogen/progestin Replacement Study (HERS): design, methods, and baseline characteristics.

The Heart and Estrogen/progestin Replacement Study (HERS) is a randomized, double-blind, placebo-controlled trial designed to test the efficacy and safety of estrogen plus progestin therapy for prevention of recurrent coronary heart disease (CHD) events in women. The participants are postmenopausal women with a uterus and with CHD as evidenced by prior myocardial infarction, coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, or other mechanical revascularization or at least 50% occlusion of a major coronary artery. Between February 1993 and September 1994, 20 HERS centers recruited and randomized 2763 women. Participants ranged in age from 44 to 79 years, with a mean age of 66.7 (SD 6.7) years. Most participants were white (89%), married (57%), and had completed high school or some college (80%). As expected, the prevalence of coronary risk factors was high: 62% were past or current smokers, 59% had hypertension, 90% had serum LDL-cholesterol of 100 mg/dL or higher, and 23% had diabetes. Each woman was randomly assigned to receive one tablet containing 0.625 mg conjugated estrogens plus 2.5 mg medroxyprogesterone acetate daily or an identical placebo. Participants will be evaluated every 4 months for an average of 4.2 years for the occurrence of CHD events (CHD death and nonfatal myocardial infarction). We will also assess other major CHD endpoints, including revascularization and hospitalization for unstable angina. The primary analysis will compare the rate of CHD events in women assigned to active treatment with the rate in those assigned to placebo. The trial was designed to have power greater than 90% to detect a 35% reduction in the incidence of CHD events, assuming a 50% lag in effect for 2 years and a 5% annual event rate in the placebo group. The design, analysis, and conduct of the study are controlled by the Steering Committee of Principal Investigators and coordinated at the University of California, San Francisco. HERS is the largest trial of any intervention to reduce the risk of recurrent CHD events in women with heart disease and is the first controlled trial to seek evidence of the efficacy and safety of postmenopausal hormone therapy to prevent recurrent CHD events.

Aged↗

Prevalence of subclinical atherosclerosis and cardiovascular disease and association with risk factors in the Cardiovascular Health Study.

The prevalence of subclinical atherosclerosis and cardiovascular disease was evaluated among the 5,201 adults aged > or = 65 years in four communities participating in the Cardiovascular Health Study from June 1989 through May 1990. A combined index based on electrocardiogram and echocardiogram abnormalities, carotid artery wall thickness and stenosis based on carotid ultrasound, decreased ankle-brachial blood pressure, and positive response to a Rose Questionnaire for angina or intermittent claudication defined subclinical disease. The prevalence of subclinical disease was 36% in women and 38.7% in men and increased with age. Among women, low-density lipoprotein cholesterol, systolic blood pressure, blood glucose, and cigarette smoking were positively associated, and high-density lipoprotein cholesterol negatively associated, with subclinical disease. In men, systolic blood pressure, blood glucose, and cigarette smoking were independent risk factors in multiple logistic regression analyses. The risk factors for subclinical disease are, therefore, similar to those for clinical disease at younger ages, especially among women. It is possible that older individuals with subclinical disease are at very high risk of developing clinical disease and that more aggressive interventions to prevent clinical disease should be oriented to individuals with subclinical disease.

Aged↗

Improved ECG models for estimation of left ventricular hypertrophy progression and regression incidence by redefinition of the criteria for a significant change in left ventricular hypertrophy status. The MRFIT Research Group. Multiple Risk Factor Intervention Trial.

Three sets of left ventricular hypertrophy (LVH) criteria were evaluated in terms of their utility for LVH progression and regression incidence estimation. Incidence comparisons were performed with and without taking short-term variability into consideration using electrocardiographic records taken at the baseline and the first annual follow-up examination of 11,969 men, aged 37 to 55 years, at the baseline of the Multiple Risk Factor Intervention Trial. Short-term total technical and biologic variability (95% range) was determined from the records of 104 men invited for a repeat electrocardiographic recording at 2-week or shorter intervals from the first recording. The results indicated that after elimination of the false fraction due to normal variability, the residual incidence estimates are so low that their utility and statistical power in monitoring changes in LVH status is very limited. It is concluded that a redefinition of LVH progression and regression criteria is needed to enhance their utility in clinical trials.

Adult↗

Prognostic significance of ventricular ectopic activity in survivors of acute myocardial infarction.

Twenty-four hour ambulatory electrocardiography was performed on 3,290 survivors of acute myocardial infarction participating in the Beta-Blocker Heart Attack Trial (BHAT). History of myocardial infarction before the qualifying event, congestive heart failure and age were independently associated with the frequency and complexity of ventricular premature beats. Of the 1,640 patients randomized to placebo therapy, 163 died (76 suffered sudden death) during a 25 month average follow-up period. Ventricular ectopic activity was an independent predictor of total mortality after taking into consideration 16 other prognostic factors describing past history, risk factors, physical examination and laboratory investigations. Seven categoric definitions of ventricular ectopic activity predicted mortality, with similar odds ratios ranging from 2.27 to 2.69. A reciprocal relation of the sensitivity and specificity of each definition in predicting mortality was observed. Three clinical criteria (ST depression, cardiomegaly and prior infarction) allowed stratification of patients into four subsets with respective mortality rates of 35.5% (three criteria present), 19.0% (two criteria), 11.5% (one criterion) and 4.7% (none). Presence of ventricular ectopic activity (greater than or equal to 10 ventricular premature beats/h or pairs, ventricular tachycardia or multiform complexes) was associated with higher mortality rates in all four risk strata. The relative risk was higher (3.86) in the lowest risk stratum (mortality 2.4% without and 9.1% with ventricular ectopic activity). Thus, in survivors of acute myocardial infarction, ventricular ectopic activity was more pronounced in patients with prior myocardial infarction and congestive heart failure. It predicted mortality independently of other factors. Although mortality ratios were similar for all seven arrhythmia definitions, a reciprocal relation between sensitivity and specificity of the definitions in predicting mortality existed; ventricular ectopic activity was associated with increased mortality in all risk strata, but with a higher risk ratio in the numerically larger, low risk subset.

Arrhythmias, Cardiac↗

Risk factors, exercise fitness and electrocardiographic response to exercise in 12,866 men at high risk of symptomatic coronary heart disease.

The association between coronary heart disease (CAD) risk factors with submaximal exercise performance was examined among 12,866 men at high risk in the Multiple Risk Factor Intervention Trial (MRFIT). Men were selected from a risk score based on serum cholesterol level, diastolic blood pressure and number of cigarettes smoked per day. Multivariate analysis using exercise ST depression as the dependent variable showed age, diastolic blood pressure and serum cholesterol level were significant positive predictors of ST depression and cigarettes per day, body mass index and heart rate at rest were significant negative predictors of ST depression. Similarly, multivariate analysis, using exercise duration as the dependent variable, revealed that age, cholesterol level, body mass index and heart rate at rest were significant negative predictors of exercise duration, whereas cigarettes per day and leisure-time physical activity were significant positive predictors. Some of these relationships with exercise performance are consistent with established epidemiologic CAD risk factor associations and others are not. The MRFIT selection process, which resulted in smokers who were significantly younger and who had significantly lower levels of other CAD risk factors than nonsmokers, was partially responsible.

Adult↗

Use of beta-adrenergic blocking agents after myocardial infarction.

Long-term clinical trials have been carried out to evaluate the effectiveness of beta-adrenergic blocking agents in modifying the natural history of myocardial infarction (MI). In most of these studies, a lower mortality rate was documented in patients receiving a beta-blocker than in those receiving placebo. The drugs may have both antiarrhythmic and antiischemic effects. In patients without contraindications to beta-blocker treatment, a relative reduction in mortality of 25% can be expected for at least one to two years, with the reduction higher in older patients or patients having complications at infarction. Study results indicate benefit from starting beta-blocker therapy early after infarction, and some benefit from starting late seems a reasonable assumption. Evidence also points to a benefit from prolonged therapy. Beta-blockers are well tolerated in most patients; those major side effects that do occur are often cardiovascular.

Adrenergic beta-Antagonists↗

Intravenous and intracoronary fibrinolytic therapy in acute myocardial infarction: overview of results on mortality, reinfarction and side-effects from 33 randomized controlled trials.

During the past 25 years, 24 randomized trials of intravenous (IV) fibrinolytic treatment have been reported, involving a total of some 6000 patients in the acute phase of myocardial infarction. Most tested IV streptokinase (SK), but a few tested IV urokinase (UK). In the past 2 or 3 years numerous small randomized trials of intracoronary (IC) SK have been started, 9 of which, involving a total of about 1000 such patients, have been reported. Because all of these IV and IC trials were small (the largest including only 747 patients), their separate results appear contradictory and unreliable. But, an overview of the data from these trials indicates that IV treatment produces a highly significant (22% +/- 5%, P less than 0.001) reduction in the odds of death, an even larger reduction in the odds of reinfarction, and an absolute frequency of serious adverse effects to set against this that is much smaller than the absolute mortality reduction. The apparent size of the mortality reduction in the IV trials was similar whether anticoagulants were compulsory or optional, whether treatment was in a coronary care unit or an ordinary ward and, surprisingly, whether treatment began early (less than 6 h from onset of symptoms) or late (generally 12-24 h). In addition, there was no evidence that UK was more effective than the less expensive SK, or that, despite their technical complexity, the new IC regimes were more effective than the old IV regimes. Even the IV schedules that have been studied in randomized trials were, however, quite complex, and the IC schedules were far more so. Perhaps partly because of this, none of them is widely used. If so, then some much simpler, and hence more widely practicable, IV SK regimes should be developed and tested. For example, a simple one hour high-dose IV SK infusion, without anticoagulation, will successfully convert virtually all of the available plasminogen into plasmin. But, it may be several years before the net effects on mortality of any more widely practicable IV SK regimes can be agreed unless many of the hospitals that do not wish routinely to use IC regimes or the complex previous IV regimes will collaborate in multicentre randomized trials that can, if necessary, continue rapid intake until some tens of thousands of patients have been randomized, and some thousands of deaths have been observed among the control and treated patients. The same, of course, may be true for any other fibrinolytic regimes (e.g. infusion of tissue plasminogen activator) if their net effects on mortality are comparable to those of IV SK.

Anticoagulants↗