Atherosclerosis, formerly considered a bland lipid storage disease, actually involves an ongoing inflammatory response. Recent advances in basic science have established a fundamental role for inflammation in mediating all stages of this disease from initiation through progression and, ultimately, the thrombotic complications of atherosclerosis. These new findings provide important links between risk factors and the mechanisms of atherogenesis. Clinical studies have shown that this emerging biology of inflammation in atherosclerosis applies directly to human patients. Elevation in markers of inflammation predicts outcomes of patients with acute coronary syndromes, independently of myocardial damage. In addition, low-grade chronic inflammation, as indicated by levels of the inflammatory marker C-reactive protein, prospectively defines risk of atherosclerotic complications, thus adding to prognostic information provided by traditional risk factors. Moreover, certain treatments that reduce coronary risk also limit inflammation. In the case of lipid lowering with statins, this anti-inflammatory effect does not appear to correlate with reduction in low-density lipoprotein levels. These new insights into inflammation in atherosclerosis not only increase our understanding of this disease, but also have practical clinical applications in risk stratification and targeting of therapy for this scourge of growing worldwide importance.

/pdf/inflammation-and-atherosclerosis-1q9qkglell.pdf

Inflammation and Atherosclerosis

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.

https://jamanetwork.com/journals/jama/articlepdf/187879/JOC80678.pdf

Randomized Trial of Estrogen Plus Progestin for Secondary Prevention of Coronary Heart Disease in Postmenopausal Women

Background Since inflammation is believed to have a role in the pathogenesis of cardiovascular events, measurement of markers of inflammation has been proposed as a method to improve the prediction of the risk of these events. Methods We conducted a prospective, nested case–control study among 28,263 apparently healthy postmenopausal women over a mean follow-up period of three years to assess the risk of cardiovascular events associated with base-line levels of markers of inflammation. The markers included high-sensitivity C-reactive protein (hs-CRP), serum amyloid A, interleukin-6, and soluble intercellular adhesion molecule type 1 (slCAM-1). We also studied homocysteine and several lipid and lipoprotein measurements. Cardiovascular events were defined as death from coronary heart disease, nonfatal myocardial infarction or stroke, or the need for coronay-revascularization procedures. Results Of the 12 markers measured, hs-CRP was the strongest univariate predictor of the risk of cardiovascular events; the relative risk of events for women in the highest as compared with the lowest quartile for this marker was 4.4 (95 percent confidence interval, 2.2 to 8.9). Other markers significantly associated with the risk of cardiovascular events were serum amyloid A (relative risk for the highest as compared with the lowest quartile, 3.0), slCAM-1 (2.6), interleukin-6 (2.2), homocysteine (2.0), total cholesterol (2.4), low-density lipoprotein (LDL) cholesterol (2.4), apolipoprotein B-100 (3.4), high-density lipoprotein (HDL) cholesterol (0.3), and the ratio of total cholesterol to HDL cholesterol (3.4). Prediction models that incorporated markers of inflammation in addition to lipids were significantly better at predicting risk than models based on lipid levels alone (P<0.001). The levels of hs-CRP and serum amyloid A were significant predictors of risk even in the subgroup of women with LDL cholesterol levels below 130 mg per deciliter (3.4 mmol per liter), the target for primary prevention established by the National Cholesterol Education Program. In multivariate analyses, the only plasma markers that independently predicted risk were hs-CRP (relative risk for the highest as compared with the lowest quartile, 1.5; 95 percent confidence interval, 1.1 to 2.1) and the ratio of total cholesterol to HDL cholesterol (relative risk, 1.4; 95 percent confidence interval, 1.1 to 1.9). Conclusions The addition of the measurement of C-reactive protein to screening based on lipid levels may provide an improved method of identifying women at risk for cardiovascular events.

https://www.nejm.org/doi/pdf/10.1056/NEJM200003233421202

C-Reactive Protein and Other Markers of Inflammation in the Prediction of Cardiovascular Disease in Women

In 1998, the American Heart Association convened Prevention Conference V to examine strategies for the identification of high-risk patients who need primary prevention. Among the strategies discussed was the measurement of markers of inflammation.1 The Conference concluded that “many of these markers (including inflammatory markers) are not yet considered applicable for routine risk assessment because of: (1) lack of measurement standardization, (2) lack of consistency in epidemiological findings from prospective studies with endpoints, and (3) lack of evidence that the novel marker adds to risk prediction over and above that already achievable through the use of established risk factors.” The National Cholesterol Education Program Adult Treatment Panel III Guidelines identified these markers as emerging risk factors,1a which could be used as an optional risk factor measurement to adjust estimates of absolute risk obtained using standard risk factors. Since these publications, a large number of peer-reviewed scientific reports have been published relating inflammatory markers to cardiovascular disease (CVD). Several commercial assays for inflammatory markers have become available. As a consequence of the expanding research base and availability of assays, the number of inflammatory marker tests ordered by clinicians for CVD risk prediction has grown rapidly. Despite this, there has been no consensus from professional societies or governmental agencies as to how these assays of markers of inflammation should be used in clinical practice.

On March 14 and 15, 2002, a workshop titled “CDC/AHA Workshop on Inflammatory Markers and Cardiovascular Disease: Applications to Clinical and Public Health Practice” was convened in Atlanta, Ga, to address these issues. The goals of this workshop were to determine which of the currently available tests should be used; what results should be used to define high risk; which patients should be tested; and the indications for which the tests would be most useful. These …

Markers of Inflammation and Cardiovascular Disease Application to Clinical and Public Health Practice: A Statement for Healthcare Professionals From the Centers for Disease Control and Prevention and the American Heart Association

Population-based epidemiologic studies have uncovered the high prevalence and wide severity spectrum of undiagnosed obstructive sleep apnea, and have consistently found that even mild obstructive sleep apnea is associated with significant morbidity. Evidence from methodologically strong cohort studies indicates that undiagnosed obstructive sleep apnea, with or without symptoms, is independently associated with increased likelihood of hypertension, cardiovascular disease, stroke, daytime sleepiness, motor vehicle accidents, and diminished quality of life. Strategies to decrease the high prevalence and associated morbidity of obstructive sleep apnea are critically needed. The reduction or elimination of risk factors through public health initiatives with clinical support holds promise. Potentially modifiable risk factors considered in this review include overweight and obesity, alcohol, smoking, nasal congestion, and estrogen depletion in menopause. Data suggest that obstructive sleep apnea is associated with all these factors, but at present the only intervention strategy supported with adequate evidence is weight loss. A focus on weight control is especially important given the expanding epidemic of overweight and obesity in the United States. Primary care providers will be central to clinical approaches for addressing the burden and the development of cost-effective case-finding strategies and feasible treatment for mild obstructive sleep apnea warrants high priority.

Epidemiology of obstructive sleep apnea: a population health perspective.

The authors ascertained cardiovascular events (myocardial infarction and angina pectoris) in 498 women with systemic lupus erythematosus seen at the University of Pittsburgh Medical Center from 1980 to 1993 (3,522 person-years). Subjects were stratified by age, and cardiovascular event incidence rates were determined. The authors compared these rates with cardiovascular event rates were determined. The authors compared these rates with cardiovascular event rates occurring over the same time period in 2,208 women of similar age participating in the Framingham Offspring Study (17,519 person-years). Age-specific rate ratios were computed to determine whether the cardiovascular events in the lupus cohort were greater than expected. The risk factors associated with cardiovascular events in women with lupus were determined. There were 33 first events (11 myocardial infarction, 10 angina pectoris, and 12 both angina pectoris and myocardial infarction) after the diagnosis of lupus: two thirds were under the age of 55 years at the time of event. Women with lupus in the 35- to 44-year age group were over 50 times more likely to have a myocardial infarction than were women of similar age in the Framingham Offspring Study (rate ratio = 52.43, 95% confidence interval 21.6-98.5). Older age at lupus diagnosis, longer lupus disease duration, longer duration of corticosteroid use, hypercholesterolemia, and postmenopausal status were more common in the women with lupus who had a cardiovascular event than in those who did not have an event. Premature cardiovascular disease is much more common in young premenopausal women with lupus than in a population sample. With the increased life expectancy of lupus patients due to improved therapy, cardiovascular disease has emerged as a significant threat to the health of these women. The impact of this problem has been underrecognized, with little focus placed on aggressive management of hypercholesterolemia and other possible risk factors.

/pdf/age-specific-incidence-rates-of-myocardial-infarction-and-29vhg1go88.pdf

Age-specific Incidence Rates of Myocardial Infarction and Angina in Women With Systemic Lupus Erythematosus: Comparison With the Framingham Study

Postmenopausal women are believed to have a higher risk of coronary artery disease than premenopausal women. In this study, we prospectively determined changes in coronary risk factors that were attributable to natural menopause in 541 healthy, initially premenopausal women 42 to 50 years of age. After approximately 2 1/2 years, 69 women had spontaneously stopped menstruating for at least 12 months, and 32 women had stopped natural menstruation and received hormone-replacement therapy for a period of at least 12 months. An equal number of age-matched premenopausal women in the study group served as controls. In women who had a natural menopause and did not receive hormone-replacement therapy, serum levels of high-density lipoprotein (HDL) cholesterol declined as compared with those of premenopausal controls (-0.09 vs. 0.00 mmol per liter; P = 0.01), and levels of low-density lipoprotein (LDL) cholesterol increased (+0.31 vs. +0.14 mmol per liter; P = 0.04). In menopausal women who received hormone-replacement therapy, HDL and LDL cholesterol levels did not change, but the levels of triglycerides (+0.42 vs. -0.04 mmol per liter; P less than 0.001), apolipoprotein A-I (+0.18 vs. +0.03 g per liter; P less than 0.01), and apolipoprotein A-II (+0.05 vs. -0.03 g per liter; P less than 0.05) increased as compared with premenopausal controls. Natural menopause did not affect blood pressure, plasma glucose or insulin levels, body weight, the total number of kilojoules consumed in the diet, or the total number of kilojoules expended in physical activity. These results suggest that a natural menopause has an unfavorable effect on lipid metabolism, which may contribute to an increase in the risk of coronary disease. Hormone-replacement therapy may prevent some of these changes.

https://www.nejm.org/doi/pdf/10.1056/NEJM198909073211004

Menopause and Risk Factors for Coronary Heart Disease

Markers of inflammation, such as C-reactive protein (CRP), are related to risk of cardiovascular disease (CVD) events in those with angina, but little is known about individuals without prevalent clinical CVD. We performed a prospective, nested case-control study in the Cardiovascular Health Study (CHS; 5201 healthy elderly men and women). Case subjects (n = 146 men and women with incident CVD events including angina, myocardial infarction, and death) and control subjects (n = 146) were matched on the basis of sex and the presence or absence of significant subclinical CVD at baseline (average follow-up, 2.4 years). In women but not men, the mean CRP level was higher for case subjects than for control subjects (P < or = .05). In general, CRP was higher in those with subclinical disease. Most of the association of CRP with female case subjects versus control subjects was in the subgroup with subclinical disease; 3.33 versus 1.90 mg/L, P < .05, adjusted for age and time of follow-up. Case-control differences were greatest when the time between baseline and the CVD event was shortest. The strongest associations were with myocardial infarction, and there was an overall odds ratio for incident myocardial infarction for men and women with subclinical disease (upper quartile versus lower three quartiles) of 2.67 (confidence interval [CI] = 1.04 to 6.81), with the relationship being stronger in women (4.50 [CI = 0.97 to 20.8]) than in men (1.75 [CI = 0.51 to 5.98]). We performed a similar study in the Rural Health Promotion Project, in which mean values of CRP were higher for female case subjects than for female control subjects, but no differences were apparent for men. Comparing the upper quintile with the lower four, the odds ratio for CVD case subjects was 2.7 (CI = 1.10 to 6.60). In conclusion, CRP was associated with incident events in the elderly, especially in those with subclinical disease at baseline.

Relationship of C-Reactive Protein to Risk of Cardiovascular Disease in the Elderly Results From the Cardiovascular Health Study and the Rural Health Promotion Project

Menopause and risk factors for coronary heart disease

Observational studies have demonstrated that women who have used postmenopausal estrogen replacement therapy (ERT) are at reduced risk of coronary heart disease. The authors examined whether premenopausal women who subsequently elected to use ERT during menopause had a better cardiovascular risk factor profile prior to use than did nonusers. A total of 541 premenopausal women had their cardiovascular risk factors and psychosocial characteristics evaluated at study entry. After approximately 8 years, 355 women had become postmenopausal, and 157 women reported ERT use during the follow-up period (mean = 93.4 months). The authors compared the premenopausal characteristics of users with those of nonusers. Relative to nonusers, ERT users were better educated (63 vs. 81% with at least some college), and prior to the use of ERT had higher levels of high density lipoprotein (HDL) cholesterol (1.49 vs. 1.59 mmol/liter), HDL2 (0.50 vs. 0.57 mmol/liter), HDL3 (0.98 vs. 1.02 mmol/liter), leisure physical activity (5,122 vs. 7,158 Kjoules), and alcohol intake (7.5 vs. 9.7 g/day), and lower levels of apolipoprotein B (0.97 vs. 0.90 g/liter), systolic blood pressure (112.1 vs. 107.1 mmHg) and diastolic blood pressure (73.8 vs. 71.4 mmHg), weight (68.5 vs. 64.2 kg), and fasting insulin (9.10 vs. 7.66 μU/liter). Prior to use of ERT, in comparison with nonusers, subsequent users reported on standardized questionnaires that they more often exhibited Type A behavior, were more aware of their feelings, motives, and symptoms, and had more symptoms of stress. Women who elect to use ERT have a better cardiovascular risk factor profile prior to the use of ERT than do women who subsequently do not use this treatment during the menopause, which supports the hypothesis that part of the apparent benefit associated with use of ERT is due to preexisting characteristics of women who use ERT. This study underscores the widely recognized importance of randomized clinical trials to estimate the direct benefit of postmenopausal ERT for protecting women from cardiovascular disease.

/pdf/prior-to-use-of-estrogen-replacement-therapy-are-users-23ygrg5vox.pdf

Elaine N. Meilahn

Papers

Age-specific Incidence Rates of Myocardial Infarction and Angina in Women With Systemic Lupus Erythematosus: Comparison With the Framingham Study

Menopause and Risk Factors for Coronary Heart Disease

Relationship of C-Reactive Protein to Risk of Cardiovascular Disease in the Elderly Results From the Cardiovascular Health Study and the Rural Health Promotion Project

Menopause and risk factors for coronary heart disease

Prior to Use of Estrogen Replacement Therapy, Are Users Healthier than Nonusers?