27th Bethesda Conference: matching the intensity of risk factor management with the hazard for coronary disease events. Task Force 4. Efficacy of risk factor management

Utility of the Framingham Risk Score in predicting secondary events in patients following percutaneous coronary intervention: A time-trend analysis

BACKGROUND

The Framingham Risk Score (FRS) effectively predicts the risk of cardiovascular events in the primary prevention setting. However, its use in identifying the risk of cardiovascular events among patients with established coronary heart disease is unknown. This study aimed to evaluate the utility of the FRS in predicting long-term secondary events in patients following percutaneous coronary intervention (PCI) across a 17-year period.

METHODS

Consecutive patients (N=25,519, male=71%, mean age=66.5±12.1years) undergoing PCI at Mayo Clinic between January 1, 1994, and December 31, 2010, were screened for cardiovascular risk factors to determine their FRS at baseline (mean score 7.0±3.3). Patients were divided into 4 groups according to their FRS 10-year predicted risk of cardiovascular disease (CVD) and were followed up for a median duration of 109months (Q1-Q3, 63-155) for the primary composite end point of cardiac death and myocardial infarction (MI) and the secondary end points of all-cause death, noncardiac death, and revascularization (surgical and percutaneous). Patients were separately divided into 5 equal temporal subsets depending on the date of PCI and were fit to a Cox model with an interaction between the FRS 10-year predicted risk and time.

RESULTS

The FRS was significantly associated with the 10-year actual risk of cardiac death and MI (both combined and separately, P<.001 respectively), noncardiac death (P<.001), all-cause death (P<.001), and revascularization (P=.018). However, the FRS discriminated risk poorly for all end points (C-statistic: cardiac death and MI, 56.8; all-cause death, 58.7; noncardiac death, 51.8; and revascularization, 51.3) even among patients presenting with acute coronary syndrome or stable angina. Over the 17-year period of time, the association between the FRS 10-year predicted risk and the 10-year actual risk of events did not change (P=.72).

CONCLUSIONS

The FRS discriminates the risk of long-term secondary events, including cardiac death, MI, and revascularization, in patients following PCI poorly, even among those presenting with acute coronary syndrome. The current study supports the development of novel secondary prevention risk models.

Impact of smoking on cardiovascular events in patients with coronary disease receiving contemporary medical therapy (from the Treating to New Targets [TNT] and the Incremental Decrease in End Points Through Aggressive Lipid Lowering [IDEAL] trials)

To define the incremental risk of cigarette smoking in patients with coronary disease receiving contemporary medical therapy, we performed a post hoc analysis of 18,885 patients by combining data from the Treating to New Targets (TNT) and the Incremental Decrease in End Points through Aggressive Lipid Lowering (IDEAL) trials. These studies compared high-dose treatment (atorvastatin 80 mg/day) to moderate-dose treatment (atorvastatin 10 mg/day in TNT and simvastatin 20 to 40 mg/day in IDEAL) in patients with established coronary heart disease. The primary end point of this pooled analysis was major cardiovascular events, a composite of cardiac death, myocardial infarction, stroke, or resuscitated cardiac arrest. At baseline 4,196 patients had never smoked, 11,513 were ex-smokers, and 3,176 were current smokers. The adjusted hazard ratio for current smokers compared to never smokers was 1.68 (95% confidence interval 1.46 to 1.94) and that for current smokers compared to ex-smokers was 1.57 (95% confidence interval 1.41 to 1.76). Event rates for current smokers compared to ex-smokers were similarly increased in each treatment group. The difference in absolute event rates between current and ex-smokers in this pooled analysis was 4.5%, which is >2 times as large as the decrease in absolute event rates between high-dose and moderate-dose statin therapy found in the IDEAL (1.7%) and TNT (2.2%) trials, respectively. In conclusion, in patients with coronary disease receiving modern medical therapy, smoking cessation is of substantial benefit with a number needed to treat of 22 to prevent a major cardiovascular event over 5 years. Smoking cessation deserves greater emphasis in secondary prevention.

The role of smoking cessation in the prevention of coronary artery disease

Smoking (tobacco addiction) is the most significant of the modifiable cardiovascular risk factors. Mistakenly described as a "habit" or "behavioral choice," the onset of tobacco addiction quickly follows the acquisition of an ability to inhale cigarette smoke and is reflected in a transformation of neurophysiologic function and nicotine-receptor density. Thereafter, comfort and a degree of neurophysiologic "equanimity" require the regular administration of nicotine. Smokers inhale thousands of other chemicals, many of which play critical roles in the initiation and accentuation of atherosclerosis by influencing vasomotor activity, vascular dysfunction, oxidation of lipids, atheroma development, and thrombosis. Smoking cessation is a priority in the management of any patient with cardiovascular disease. The benefits of cessation accrue rapidly in such patients and have a pronounced effect on the likelihood of disease progression, hospital readmission, and mortality. All physicians must be familiar with the principles of cessation practice and be able to initiate smoking cessation attempts.

Efficacy and safety of varenicline for smoking cessation in patients with cardiovascular disease: a randomized trial

BACKGROUND

Smoking cessation is a key component of secondary cardiovascular disease prevention. Varenicline, a partial alpha4beta2 nicotinic acetylcholine receptor agonist, is effective for smoking cessation in healthy smokers, but its efficacy and safety in smokers with cardiovascular disease are unknown.

METHODS AND RESULTS

A multicenter, randomized, double-blind, placebo-controlled trial compared the efficacy and safety of varenicline with placebo for smoking cessation in 714 smokers with stable cardiovascular disease. Participants received varenicline (1 mg twice daily) or placebo, along with smoking-cessation counseling, for 12 weeks. Follow-up lasted 52 weeks. The primary end point was carbon monoxide-confirmed continuous abstinence rate for weeks 9 through 12 (last 4 weeks of treatment). The continuous abstinence rate was higher for varenicline than placebo during weeks 9 through 12 (47.0% versus 13.9%; odds ratio, 6.11; 95% confidence interval [CI], 4.18 to 8.93) and weeks 9 through 52 (19.2% versus 7.2%; odds ratio, 3.14; 95% CI, 1.93 to 5.11). The varenicline and placebo groups did not differ significantly in cardiovascular mortality (0.3% versus 0.6%; difference, -0.3%; 95% CI, -1.3 to 0.7), all-cause mortality (0.6% versus 1.4%; difference, -0.8%; 95% CI, -2.3 to 0.6), cardiovascular events (7.1% versus 5.7%; difference, 1.4%; 95% CI, -2.3 to 5.0), or serious adverse events (6.5% and 6.0%; difference, 0.5%; 95% CI, -3.1 to 4.1). As a result of adverse events, 9.6% of varenicline and 4.3% of placebo participants discontinued study drug.

CONCLUSIONS

Varenicline is effective for smoking cessation in smokers with cardiovascular disease. It was well tolerated and did not increase cardiovascular events or mortality; however, trial size and duration limit definitive conclusions about safety. Clinical Trial Registration Information- URL: http://www.clinicaltrials.gov/ct2/show/NCT00282984. Unique identifier: NCT00282984.

Effect of an educational program (PEGASE) on cardiovascular risk in hypercholesterolaemic patients

BACKGROUND

Many studies have demonstrated a gap between guidelines for the prevention of cardiovascular disease (CVD) and their implementation in clinical practice.

AIM

The PEGASE education program has been devised with an aim to improve the management of patients at high risk of CVD.

METHODS

In a multicentre study carried out from 2001-2004 in France, 96 participating physicians were randomized into a "trained" group, which included 398 "educated" patients, and a "non-trained" group, which included 242 "non-educated" patients. Educated patients received six hospital-based educational sessions, four collective and two individual. Framingham score, smoking, lipid levels, glycaemia, blood pressure, dietary intake and drug compliance, as well as quality of life, were evaluated at baseline (M0) and 6 months (M6). The primary endpoint of the study was the efficacy of the PEGASE program in reducing global CVD risk in high-risk patients.

RESULTS

The Framingham score was calculated for 473 patients. The Framingham score improved significantly at M6 vs M0 in the educated group (13.0 +/- 8.21 vs 13.6 +/- 8.48, d = -0.658, p = 0.016), but not in the non-educated group (12.5 +/- 8.19 vs 12.4 +/- 7.81, d = +0.064, p = 0.836); the mean change between the two groups did not reach significance. Quality of life, LDL-c level and diet scores improved in the "educated" group only.

CONCLUSIONS

The PEGASE education program improved risk factors for CVD, although global assessment by Framingham score was not significantly different between groups. This program, aimed at meeting needs and expectations of patients and physicians, was easily implemented in all hospital centres.

General cardiovascular risk profile for use in primary care: the Framingham Heart Study

BACKGROUND

Separate multivariable risk algorithms are commonly used to assess risk of specific atherosclerotic cardiovascular disease (CVD) events, ie, coronary heart disease, cerebrovascular disease, peripheral vascular disease, and heart failure. The present report presents a single multivariable risk function that predicts risk of developing all CVD and of its constituents.

METHODS AND RESULTS

We used Cox proportional-hazards regression to evaluate the risk of developing a first CVD event in 8491 Framingham study participants (mean age, 49 years; 4522 women) who attended a routine examination between 30 and 74 years of age and were free of CVD. Sex-specific multivariable risk functions ("general CVD" algorithms) were derived that incorporated age, total and high-density lipoprotein cholesterol, systolic blood pressure, treatment for hypertension, smoking, and diabetes status. We assessed the performance of the general CVD algorithms for predicting individual CVD events (coronary heart disease, stroke, peripheral artery disease, or heart failure). Over 12 years of follow-up, 1174 participants (456 women) developed a first CVD event. All traditional risk factors evaluated predicted CVD risk (multivariable-adjusted P<0.0001). The general CVD algorithm demonstrated good discrimination (C statistic, 0.763 [men] and 0.793 [women]) and calibration. Simple adjustments to the general CVD risk algorithms allowed estimation of the risks of each CVD component. Two simple risk scores are presented, 1 based on all traditional risk factors and the other based on non-laboratory-based predictors.

CONCLUSIONS

A sex-specific multivariable risk factor algorithm can be conveniently used to assess general CVD risk and risk of individual CVD events (coronary, cerebrovascular, and peripheral arterial disease and heart failure). The estimated absolute CVD event rates can be used to quantify risk and to guide preventive care.

Effects of a Problem-based Learning Rehabilitation Program on Physical Activity in Patients With Coronary Artery Disease

PURPOSE

To evaluate the effects of a problem-based learning (PBL) rehabilitation program on physical activity.

METHODS

We randomized 207 consecutive patients younger than 70 years, with a recent event of coronary artery disease (CAD), to a PBL group (n = 104) or a control group (n = 103). In addition to standard treatment, the PBL patients participated in a 1-year program with 13 sessions in small groups, where learning needs and behavior change were focused upon. Physical activity was assessed by means of interviews with all patients and by an activity monitor in 69 patients at pretest and in 175 after 1 year.

RESULTS

Only small differences between groups were found at posttest. Interview data revealed significantly less activity at low-intensity level in the control group, whereas the activity monitor showed no significant differences. No changes were found in total physical activity during the year within the 2 groups. The self-reported physical activity indicating a level of brisk walking was markedly higher than that measured by the activity monitor, the latter indicating that only 35% of the patients achieved a 10-minute period of continued physical activity per day on an adequate level.

CONCLUSIONS

Our PBL program had no important impact on the physical activity pattern of patients with CAD. The activity monitor is a feasible way of measuring physical activity in these patients, indicating a lower level of physical activity than interview data.

Identification of Women's Coronary Heart Disease and Risk Factors Prior to First Myocardial Infarction

PURPOSE

To understand when women's coronary heart disease (CHD) and CHD risk factors are recognized prior to first myocardial infarction (MI).

METHODS

Medical record review of the 10 years prior to incident MI among women with a confirmed incident MI between January 1, 1996, and December 31, 2001, to determine the timing of CHD diagnosis as well as assessment and treatment for risk factors.

RESULTS

One hundred fifty women had incident MIs during the study period. They made 8732 ambulatory visits and had 457 hospitalizations during the period of review (mean 9.1 years, range 6.2-10 years). Average age at incident MI was 74.7 years (SD 12.6, range 38.9-99.8 years). A CHD diagnosis prior to first MI was present in 52% (n = 78) of the women but was less common in those <70 years (p = 0.001). All but 3 women had one or more modifiable risk factors identified prior to their first MI. Treatment of recognized risk factors varied from 81% (antihypertension medications) to only 28% (drug therapy for abnormal lipid levels). Having a diagnosis of CHD was associated with an increased likelihood of having identified risk factors and receiving drug treatment for identified risk factors.

CONCLUSIONS

Women with undiagnosed CHD (48%) and those with unrecognized or untreated risk factors for CHD, especially younger women, represent missed opportunities for prevention of cardiac events.

Impact of a home communication intervention for coronary artery bypass graft patients with ischemic heart failure on self-efficacy, coronary disease risk factor modification, and functioning

OBJECTIVE

The purpose of this study is to determine the impact of a home communication intervention (HCI) for ischemic heart failure Coronary Artery Bypass Graft (CABG) patients >/= 65 years of age on self-efficacy, coronary artery disease risk factor modification and functioning posthospitalization.

DESIGN

A randomized clinical trial with repeated measures was used.

SAMPLE

A subsample of ischemic heart failure CABG surgery patients (n = 35) was drawn from the parent study of 180 CABG patients.

RESULTS

HCI participants (n = 18) had significantly higher adjusted mean self-efficacy scores [F(1, 29) = 6.40, P <.05] and adjusted mean levels of functioning (physical, general health, mental, and vitality functioning) compared with the routine care group (n = 17), using repeated measures analysis of covariance with baseline scores as covariates. There were also significant effects of time on bodily pain and role emotional functioning. Significantly higher exercise adherence (t = 3.09, P <.01) and lower reported stress (t = 3.77, P <.01) at 3 months after surgery was reported by HCI subjects.

CONCLUSIONS

Data from this pilot study can be used to strengthen the HCI intervention with more tailored strategies for vulnerable subgroups of CABG patients.

Cardiovascular risk factors in patients discharged from departments of internal medicine---the Italian FADOI-2 study

Background: The goal of this study was to describe mean levels, distribution, and treatment of cardiovascular risk factors among patients admitted to departments of internal medicine. Methods: Clinical records were obtained from patients discharged during the last week of October 1999 in 345 departments of internal medicine in Italy. A number of cardiovascular risk factors, diagnoses, and personal characteristics were analyzed in a total of 7476 patients aged 35 years or older. Not all of these personal characteristics were available for each patient. Results: In general, the levels of cardiovascular risk factors present in patients were high, with hypertension and diabetes the most frequently encountered. The risk of coronary heart disease (CHD) over 10 years was estimated using an Italian algorithm that provided high probability levels, mainly among cardiovascular patients (410 per 1000 in 10 years on average in both genders). Overall, 55% of the men and 50% of the women had levels above 200 per 1000 in 10 years, corresponding to the conventional threshold for intensive individual intervention on risk factors. At discharge, about 70% of hypertensive patients were being treated for their condition, while the same was true of only 25% of dyslipidemic patients. Conclusions: Although data are incomplete, the coronary risk profile of patients admitted to departments of internal medicine suggests a high probability of future events. Treatment of risk factors amenable to effective action is still far from optimal, especially in the area of elevated blood lipids.

Psychosocial stress and cardiovascular disease: pathophysiological links

The remarkable decline in cardiovascular disease (CVD) experienced in developed countries over the last 40 years appears to have abated. Currently, many CVD patients continue to show cardiac events despite optimal treatment of traditional risk factors. This evidence suggests that additional interventions, particularly those aimed at nontraditional factors, might be useful for continuing the decline. Psychosocial stress is a newly recognized (nontraditional) risk factor that appears to contribute to all recognized mechanisms underlying cardiac events, specifically, (a) clustering of traditional cardiovascular risk factors, (b) endothelial dysfunction, (c) myocardial ischemia, (d) plaque rupture, (e) thrombosis, and (f) malignant arrhythmias. A better understanding of the behavioral and physiologic associations between psychosocial stress and CVD will assist researchers in identifying effective approaches for reducing or reversing the damaging effects of stress and may lead to further reductions of CVD morbidity and mortality.

Evidence against a role of physiological concentrations of estrogen in post-myocardial infarction remodeling

OBJECTIVES

The purpose of this study was to examine whether endogenous estrogen deficiency induced by ovariectomy affects chronic left ventricular dysfunction post-myocardial infarction (MI).

BACKGROUND

Epidemiologic findings suggest that mortality of postmenopausal women is increased after MI, but the underlying mechanisms are unknown.

METHODS

Rats were either not ovariectomized (non-OVX), ovariectomized (OVX) or ovariectomized and treated with subcutaneous 17-beta-estradiol (E2) pellets (OVX + E2). Two weeks later, animals were sham-operated (Sham) or left coronary artery ligated (MI). Eight weeks later, in vivo echocardiographic and hemodynamic measurements were performed. Thereafter, hearts were isolated and perfused isovolumically.

RESULTS

Mean infarct size was similar among the three MI groups. Ovariectomy decreased serum E2 levels (11 +/- 4 vs. 49 +/- 11 pg/ml in non-OVX, p < 0.01) and increased body weight. These changes were reversed by E2 replacement. The degree of cardiac hypertrophy was similar for all groups post-MI. Left ventricular diameters were increased post-MI (8.9 +/- 0.4 in non-OVX + MI vs. 6.7 +/- 0.2 mm in non-OVX + Sham hearts, p < 0.0001), but OVX or OVX + E2 replacement did not alter left ventricular diameters in post-MI and Sham hearts. Left ventricular fractional shortening was severely impaired post-MI (19 +/- 2% vs. 50 +/- 3 in non-OVX + Sham hearts, p < 0.0001) with no influence of hormonal status. Left ventricular end-diastolic pressure, measured in vivo, was increased in all MI groups without significant differences between groups. Pressure-volume curves, obtained in perfused hearts, demonstrated a right and downward shift with reduced maximum left ventricular developed pressure post-MI (75 +/- 6 vs. 108 +/- 3 mm Hg in non-OVX + Sham hearts, p < 0.001) and were also unaffected by either OVX or E2 replacement.

CONCLUSIONS

Chronic endogenous estrogen deficiency does not have major effects on the development of cardiac hypertrophy, dysfunction and dilation post-MI.

Hypertriglyceridemia: changes in the plasma lipoproteins associated with an increased risk of cardiovascular disease

There is a growing body of evidence from epidemiologic, clinical, and laboratory data that indicates that elevated triglyceride levels are an independent risk factor for cardiovascular disease. Identification and quantification of atherogenic lipoproteins in patients with hypertriglyceridemia are important steps in the prevention of cardiovascular disease. Increased levels of apoC-III, apoC-I, or apoA-II on the apoB-containing lipoproteins may alter lipoprotein metabolism and result in the accumulation of atherogenic remnants. Hypertriglyceridemic patients at risk for cardiovascular disease often develop a lipoprotein profile characterized by elevated triglyceride, dense LDL, and low HDL cholesterol. Understanding that each of these factors contributes separately to the patient's risk of cardiovascular disease can help physicians provide patients with more effective risk-reduction programs for cardiovascular disease.

Determinants of atherosclerosis in the young. Pathobiological Determinants of Atherosclerosis in Youth (PDAY) Research Group

A multicenter cooperative study, Pathobiological Determinants of Atherosclerosis in Youth, examined the relation of the risk factors for adult coronary artery disease to atherosclerosis in nearly 3,000 persons, aged 15-34 years, who died from accidents, homicides, and suicides and were autopsied in forensic laboratories. Very-low-density lipoprotein (VLDL) plus low-density lipoprotein (LDL) cholesterol levels were positively, and high-density lipoprotein (HDL) cholesterol levels were negatively, associated with both fatty streaks and raised lesions in the aorta and right coronary artery, particularly after age 25. Elevated glycohemoglobin levels were associated with raised lesions throughout the 15-34-year age span. Body mass index was associated with both fatty streaks and raised lesions of the right coronary artery in men but not in women. Smoking was associated with a 3-fold increase in raised lesions of the abdominal aorta in the 25-34-year age group. Women lagged after men in the extent of raised lesions in the right coronary artery by about 5 years, but the effects of risk factors in women, except for adiposity, were similar to those in men. The risk factors for adult coronary artery disease accelerate atherogenesis in the teenage years and their effects are amplified in young adulthood, 20-30 years before coronary artery disease becomes clinically manifest. Long-range prevention of adult coronary artery disease will require control of the risk factors early in life.

Behavioral issues in the efficacy versus effectiveness of pharmacologic agents in the prevention of cardiovascular disease

A number of pharmacologic interventions are now recommended for the prevention of cardiovascular disease, based on the results of randomized controlled trials. These include antihypertensive drugs, lipid-lowering agents, antiplatelet and anticoagulant drugs, estrogen replacement therapy, beta-blockers, and angiotensin converting enzyme (ACE) inhibitors. It is likely that additional pharmacologic interactions will soon be proven efficacious. Despite the strength of this evidence and the development of clinical guidelines incorporating their use, a surprisingly low proportion of patients are actively treated with these agents. There may be a variety of explanations for this, including barriers at the level of the patient, health care provider, and health care institution. Finally, a number of questions remain as to the optimal combination of interventions, both behavioral and pharmacologic, which will yield maximal reduction in risk. The description of factors which reduce the effectiveness of pharmacologic interventions below the efficacy demonstrated in randomized clinical trials should be a fertile area for epidemiologic and behavioral research.

Lipid lowering in a multidisciplinary clinic compared with primary physician management

A multidisciplinary lipid reduction clinic achieved greater reduction of serum cholesterol when compared with primary physicians among patients with coronary heart disease. The lipid clinic was more likely than the primary physicians to prescribe lipid-lowering medication, to prescribe multiple medications, and to use drug doses in excess of the "starting dose."

A new model for risk stratification and delivery of cardiovascular rehabilitation services in the long-term clinical management of patients with coronary artery disease

This model for risk stratification includes variables that classify patients for Risk of Event similar to current models of risk stratification, as well as variables that stratify patients for Risk of Progression of Atherosclerosis by established risk factors. Categories of risk are established using accepted data from the literature for each risk factor that targets regression or plaque stabilization as the goal for Low Risk. A case-rate charging system and the proposed removal of time restrictions for length of cardiovascular rehabilitation fit neatly into the present climate for health care. Health maintenance organizations will be seeking programs that use similar models to address cost issues inherent in cardiovascular rehabilitation programs under current fee-for-service models. Improved outcomes will also be targets for these programs and case-management lends itself to disease management, thus, improved outcomes. Tracking outcomes becomes even more important to both the provider and the insurer because results drive referrals. Likewise, removal of the time restriction for cardiovascular rehabilitation allows programs to individualize care and to target risk factors that are not only most deleterious, but also where patients show readiness for change. The changing environment of health care virtually mandates change in cardiovascular rehabilitation. It is imperative that programs manage the disease process, are effective in achieving outcomes that affect both patient function and the disease process, and are cost effective. This model for risk stratification and delivery of services addresses these requirements and provides a beginning for implementing these changes in cardiovascular rehabilitation.

Effectiveness of atorvastatin for reducing low-density lipoprotein cholesterol to National Cholesterol Education Program treatment goals

Atorvastatin is a highly efficacious hydroxymethylglutaryl-coenzyme A reductase inhibitor that has been shown to reduce low-density lipoprotein cholesterol by 40% to 60%. Monotherapy with atorvastatin (10 to 80 mg/day) is well-tolerated, convenient, and appears to be effective for achieving National Cholesterol Education Program treatment goals in most patients, regardless of risk status.

The secondary prevention of coronary artery disease

Randomized clinical trials demonstrate the efficacy of medical secondary prevention in coronary disease patients. The magnitude of risk reduction with exercise, diet, lipid modification, and smoking cessation is similar to other medical therapies for coronary disease such as aspirin, beta blockers, as well as coronary bypass surgery, (Table VI) In contrast to these therapies, however, secondary prevention stabilizes angiographic progression in about 50% of patients and induces regression in about 25% of patients. Both symptoms and perceived quality of life also are beneficially altered by secondary prevention programs, although possibly not by the magnitude reported for bypass surgery. These clinical trial results have led the American Heart Association, and the American College of Cardiology to strongly endorse secondary prevention. A reasonable projection based on these clinical trial data is that widespread use of these recommendations in the 12 million established coronary disease patients would significantly reduce coronary mortality and morbidity.

Estrogen replacement therapy after coronary angioplasty in women

OBJECTIVES

The purpose of this study was to assess the effects of estrogen replacement therapy on long-term outcome, including restenosis, myocardial infarction, stroke and death after a first percutaneous transluminal coronary angioplasty (PTCA) procedure, in postmenopausal women.

BACKGROUND

Observational and epidemiologic studies, basic laboratory research and clinical trials consistently suggest that estrogen replacement therapy is associated with beneficial cardiovascular effects in women. These cardioprotective actions may be particularly relevant to women with coronary artery disease, such as those who have undergone PTCA.

METHODS

This was a retrospective study that included 337 women who underwent elective PTCA between 1982 and 1994. The treatment group consisted of 137 consecutive women receiving long-term estrogen therapy at the time of elective PTCA and during follow-up. The control group comprised 200 women who were computer-matched with the estrogen group. The mean follow-up period was 65 +/- 35 months.

RESULTS

Actuarial survival was superior in the estrogen group; the 7-year survival rate was 93% for the estrogen group versus 75% for the control group (p = 0.001). The cardiovascular event rate (death, nonfatal myocardial infarction or nonfatal stroke) was significantly lower in the estrogen group at 7 years (12% vs. 35% in the control group, p = 0.001). The need for subsequent revascularization during follow-up was similar in the two groups. Multivariable analysis identified diabetes, estrogen therapy (adjusted risk ratio 0.38, 95% confidence interval 0.19 to 0.79) and left ventricular ejection fraction < 40% as independent correlates of cardiovascular death or myocardial infarction during follow-up.

CONCLUSIONS

Estrogen replacement therapy was associated with an improved long-term outcome after PTCA in postmenopausal women.

Generation of a polyclonal antibody against lipid peroxide-modified proteins

A specific polyclonal antibody against the lipid peroxide (LOOH)-modified rabbit serum albumin (RSA) was generated in rabbits. The antibody selectively recognized the modified protein in a concentration-dependent manner and did not cross react with aldehyde-modified proteins or proteins directly oxidized with the free radical generator 2,2'-azobis (2-amidinopropane) hydrochloride (AAPH). Oxidized low-density lipoprotein (Ox-LDL), but not native LDL, was also recognized by the antibody in a concentration-dependent manner. The antibody also cross reacted with several other proteins modified by LOOH suggesting that the antibody is directed towards a common epitope and not towards the protein sequence. Western blot analysis of normal human plasma showed that at least three different proteins are recognized by the antibody. RAW cells, preincubated with LOOH, were immunostained with the antibody and the antigenic epitopes were present intracellularly, while controls lacking in the primary antibodies failed to show immunoreactivity. Atherosclerotic arteries from cholesterol-fed monkeys and human atherosclerotic lesions were also immunostained by the antibody. The immunoreactivity was co-localized in areas rich in foam cell macrophages. These results suggest that LOOH-modified proteins present an unique antigenic epitope that may represent a primary product of interaction of LOOH with proteins.