Job strain and risk of acute recurrent coronary heart disease events

Context  There is evidence that job strain increases the risk of a first coronary heart disease (CHD) event. However, little is known about its association with the risk of recurrent CHD events after a first myocardial infarction (MI). Objective  To determine whether job strain increases the risk of recurrent CHD events. Design, Setting, and Patients  Prospective cohort study of 972 men and women aged 35 to 59 years who returned to work after a first MI and were then followed up between February 10, 1996, and June 22, 2005. Patients were interviewed at baseline (on average, 6 weeks after their return to work), then after 2 and 6 years subsequently. Job strain, a combination of high psychological demands and low decision latitude, was evaluated in 4 quadrants: high strain (high demands and low latitude), active (high demands and high latitude), passive (low demands and low latitude), and low strain. A chronic job strain variable was constructed based on the first 2 interviews, and patients were divided into those exposed to high strain at both interviews and those unexposed to high strain at 1 or both interviews. The survival analyses were presented separately for 2 periods: before 2.2 years and at 2.2 years and beyond. Main Outcome Measure  The outcome was a composite of fatal CHD, nonfatal MI, and unstable angina. Results  The outcome was documented in 206 patients. In the unadjusted analysis, chronic job strain was associated with recurrent CHD in the second period after 2.2 years of follow-up (hazard ratio [HR], 2.20; 95% CI, 1.32-3.66; respective event rates for patients exposed and unexposed to chronic job strain, 6.18 and 2.81 per 100 person-years). Chronic job strain remained an independent predictor of recurrent CHD in a multivariate model adjusted for 26 potentially confounding factors (HR, 2.00; 95% CI, 1.08-3.72). Conclusion  Chronic job strain after a first MI was associated with an increased risk of recurrent CHD.      

Major risk factors as antecedents of fatal and nonfatal coronary heart disease events

Context  A frequently cited concept is that individual major risk factors for coronary heart disease (CHD) are absent in many patients (perhaps >50%) with CHD. However, prior studies have not systematically evaluated the extent to which CHD patients have previous exposure to at least 1 risk factor, including diabetes, cigarette smoking, or clinically elevated levels of cholesterol or blood pressure. Objective  To determine the frequency of exposure to major CHD risk factors. Design, Setting, and Participants  Three prospective cohort studies were included: the Chicago Heart Association Detection Project in Industry, with a population sample of 35 642 employed men and women aged 18 to 59 years; screenees for the Multiple Risk Factor Intervention Trial, including 347 978 men aged 35 to 57 years; and a population-based sample of 3295 men and women aged 34 to 59 years from the Framingham Heart Study (FHS). Follow-up lasted 21 to 30 years across the studies. Main Outcome Measures  Fatal CHD in all cohorts and nonfatal myocardial infarction (MI) in the FHS, compared by exposure to major CHD risk factors, defined as total cholesterol of at least 240 mg/dL (=" BORDER="0">6.22 mmol/L), systolic blood pressure of at least 140 mm Hg, diastolic blood pressure of at least 90 mm Hg, cigarette smoking, and diabetes. Participants were stratified by sex and age (18-39 vs 40-59 years). Results  For fatal CHD (n = 20 995), exposure to at least 1 clinically elevated major risk factor ranged from 87% to 100%. Among those aged 40 to 59 years at baseline with fatal CHD (n = 19 263), exposure to at least 1 major risk factor ranged from 87% to 94%. For nonfatal MI, prior exposure was documented in 92% (95% CI, 87%-96%) (n = 167) of men aged 40 to 59 years at baseline and in 87% (95% CI, 80%-94%) (n = 94) of women in this age group. Conclusions  Antecedent major CHD risk factor exposures were very common among those who developed CHD, emphasizing the importance of considering all major risk factors in determining CHD risk estimation and in attempting to prevent clinical CHD. These results challenge claims that CHD events commonly occur in persons without exposure to at least 1 major CHD risk factor.      

Favorable cardiovascular risk profile in young women and long-term risk of cardiovascular and all-cause mortality

Context  For women, impact of cardiovascular risk factors measured in young adulthood, particularly favorable (low-risk) profile, on mortality has been difficult to assess due to low short-term death rates. Objective  To assess the relationship of baseline coronary risk factor status to mortality from coronary heart disease (CHD), cardiovascular diseases (CVDs), and all causes in young women. Design  Prospective cohort study. Setting and Participants  A total of 7302 women aged 18 to 39 years without prior CHD or major electrocardiographic abnormalities screened between 1967 and 1973 for the Chicago Heart Association Detection Project in Industry. Risk groups were defined using national guidelines for values of systolic and diastolic blood pressure, serum cholesterol level, body mass index, presence of diabetes, and smoking status. Participants were divided into 4 groups: low risk, 0 risk factors high but 1 or more unfavorable, 1 only risk factor high, and 2 or more risk factors high. Main Outcome Measures  All-cause mortality, CHD mortality, and CVD mortality; hazard ratio of outcome measures comparing low-risk group with other groups. Results  Only 20% met low-risk criteria; 59% had high levels of 1 or more risk factors. During an average follow-up of 31 years, there were 47 CHD deaths, 94 CVD deaths, and 469 deaths from all causes. The age-adjusted CVD death rate per 10 000 person-years was lowest for low-risk women and increased with the number of risk factors, ie, 1.5, 1.7, 5.0, and 9.1 for low-risk; 0, 1, and 2 or more risk factors high, respectively. Multivariate-adjusted CVD mortality hazard ratio for low-risk women was 0.19 (95% confidence interval, 0.08-0.45) compared with women with 2 or more risk factors high. Similar patterns were observed for CHD and all-cause mortality and for both blacks and whites. Conclusion  For women with favorable levels for all 5 major risk factors at younger ages, CHD and CVD are rare; long-term and all-cause mortality are much lower compared with others.      

Prevalence of conventional risk factors in patients with coronary heart disease

Context  It is commonly suggested that more than 50% of patients with coronary heart disease (CHD) lack any of the conventional risk factors (cigarette smoking, diabetes, hyperlipidemia, and hypertension). This claim implies that other factors play a significant role in CHD and has led to considerable interest in nontraditional risk factors and genetic causes of CHD. Objective  To determine the prevalence of the 4 conventional risk factors among patients with CHD. Design, Setting, and Patients  In 2002-2003, we analyzed data for 122 458 patients enrolled in 14 international randomized clinical trials of CHD conducted during the prior decade. Patients included 76 716 with ST-elevation myocardial infarction, 35 527 with unstable angina/non–ST-elevation myocardial infarction, and 10 215 undergoing percutaneous coronary intervention. Main Outcome Measures  Prevalence of each conventional risk factor and number of conventional risk factors present among patients with CHD, compared between men and women and by age at trial entry. Results  Among patients with CHD, at least 1 of the 4 conventional risk factors was present in 84.6% of women and 80.6% of men. In younger patients (men 55 years and women 65 years) and most patients presenting either with unstable angina or for percutaneous coronary intervention, only 10% to 15% of patients lacked any of the 4 conventional risk factors. This pattern was largely independent of sex, geographic region, trial entry criteria, or prior CHD. Premature CHD was related to cigarette smoking in men and cigarette smoking and diabetes in women. Smoking decreased the age at the time of CHD event (at trial entry) by nearly 1 decade in all risk factor combinations. Conclusions  In direct contrast with conventional thinking, 80% to 90% of patients with CHD have conventional risk factors. Although research on nontraditional risk factors and genetic causes of heart disease is important, clinical medicine, public health policies, and research efforts should place significant emphasis on the 4 conventional risk factors and the lifestyle behaviors causing them to reduce the epidemic of CHD.      

Cardiovascular disease outcomes during 6.8 years of hormone therapy: Heart and Estrogen/progestin Replacement Study follow-up (HERS II)

Context  The Heart and Estrogen/progestin Replacement Study (HERS) found no overall reduction in risk of coronary heart disease (CHD) events among postmenopausal women with CHD. However, in the hormone group, findings did suggest a higher risk of CHD events during the first year, and a decreased risk during years 3 to 5. Objective  To determine if the risk reduction observed in the later years of HERS persisted and resulted in an overall reduced risk of CHD events with additional years of follow-up. Design and Setting  Randomized, blinded, placebo-controlled trial of 4.1 years' duration (HERS) and subsequent unblinded follow-up for 2.7 years (HERS II) conducted at outpatient and community settings at 20 US clinical centers. Participants  A total of 2763 postmenopausal women with CHD and average age of 67 years at enrollment in HERS; 2321 women (93% of those surviving) consented to follow-up in HERS II. Intervention  Participants were randomly assigned to receive 0.625 mg/d of conjugated estrogens and 2.5 mg of medroxyprogesterone acetate (n = 1380), or placebo (n = 1383) during HERS; open-label hormone therapy was prescribed at personal physicians' discretion during HERS II. The proportions with at least 80% adherence to hormones declined from 81% (year 1) to 45% (year 6) in the hormone group, and increased from 0% (year 1) to 8% (year 6) in the placebo group. Main Outcome Measures  The primary outcome was nonfatal myocardial infarction and CHD death. Secondary cardiovascular events were coronary revascularization, hospitalization for unstable angina or congestive heart failure, nonfatal ventricular arrhythmia, sudden death, stroke or transient ischemic attack, and peripheral arterial disease. Results  There were no significant decreases in rates of primary CHD events or secondary cardiovascular events among women assigned to the hormone group compared with the placebo group in HERS, HERS II, or overall. The unadjusted relative hazard (RH) for CHD events in HERS was 0.99 (95% confidence interval [CI], 0.81-1.22); HERS II, 1.00 (95% CI, 0.77-1.29); and overall, 0.99 (0.84-1.17). The overall RHs were similar after adjustment for potential confounders and differential use of statins between treatment groups (RH, 0.97; 95% CI, 0.82-1.14), and in analyses restricted to women who were adherent to randomized treatment assignment (RH, 0.96; 95% CI, 0.77-1.19). Conclusions  Lower rates of CHD events among women in the hormone group in the final years of HERS did not persist during additional years of follow-up. After 6.8 years, hormone therapy did not reduce risk of cardiovascular events in women with CHD. Postmenopausal hormone therapy should not be used to reduce risk for CHD events in women with CHD.      

Major and minor ECG abnormalities in asymptomatic women and risk of cardiovascular events and mortality

Context  Data are sparse regarding the prevalence, incidence, and independent prognostic value of minor and/or major electrocardiographic (ECG) abnormalities in asymptomatic postmenopausal women. There is no information on the effect, if any, of hormonal treatment on the prognostic value of the ECG. Objective  To examine association of minor and major baseline and incident ECG abnormalities with long-term cardiovascular morbidity and mortality. Design, Setting, and Participants  Post-hoc analysis of the estrogen plus progestin component of the Women's Health Initiative study, a randomized controlled primary prevention trial of 14 749 postmenopausal asymptomatic women with intact uterus who received 1 daily tablet containing 0.625 mg of oral conjugated equine estrogen and 2.5 mg of medroxyprogesterone acetate or a matching placebo. Participants were enrolled from 1993 to 1998, and the estrogen plus progestin trial was stopped on July 7, 2002. Main Outcome Measures  The Novacode criteria were used to define minor, major, and incident ECG abnormalities. Cardiovascular end points included incident coronary heart disease (CHD) and cardiovascular disease (CVD) events. Results  Among women with absent (n = 9744), minor (n = 4095), and major (n = 910) ECG abnormalities, there were 118, 91, and 37 incident CHD events, respectively. The incident annual CHD event rates per 10 000 women with absent, minor, or major ECG abnormalities were 21 (95% confidence interval [CI], 18-26), 40 (95% CI, 32-49), and 75 (95% CI, 54-104), respectively. After 3 years of follow-up, 5% of women who had normal ECG at baseline developed new ECG abnormalities with an annual CHD event rate of 85 (95% CI, 44-164) per 10 000 women. The adjusted hazard ratios for CHD events were 1.55 (95% CI, 1.14-2.11) for minor baseline, 3.01 (95% CI, 2.03-4.46) for major baseline, and 2.60 (95% CI, 1.08-6.27) for incident ECG abnormalities. There were no significant interactions between hormone treatment assignment and ECG abnormalities for risk prediction of cardiovascular end points. For prediction of CHD events, the addition of ECG findings to the Framingham risk score increased from 0.69 to 0.74 the area under the receiver operating characteristic curve. Similar findings were found for incident CVD events. Conclusions  Among asymptomatic postmenopausal women, clinically relevant baseline and incident ECG abnormalities are independently associated with increased risk of cardiovascular events and mortality, and the information is incremental to the established method of risk stratification. Trial Registration  clinicaltrials.gov Identifier: NCT00000611      

Retinal arteriolar narrowing and risk of coronary heart disease in men and women. The Atherosclerosis Risk in Communities Study

Context  Microvascular processes have been hypothesized to play a greater role in the development of coronary heart disease (CHD) in women than in men; however, prospective clinical data are limited. Objective  To examine the association between retinal arteriolar narrowing, a marker of microvascular damage from hypertension and inflammation, and incident CHD in healthy middle-aged women and men. Design, Setting, and Participants  The Atherosclerosis Risk in Communities Study, an ongoing prospective, population-based cohort study in 4 US communities initiated in 1987-1989. Retinal photographs were taken in 9648 women and men aged 51 to 72 years without CHD at the third examination (1993-1995). To quantify retinal arteriolar narrowing, the photographs were digitized, individual arteriolar and venular diameters were measured, and a summary arteriole-to-venule ratio (AVR) was calculated. Main Outcome Measure  Risk of CHD associated with retinal arteriolar narrowing. Results  During an average 3.5 years of follow-up, 84 women and 187 men experienced incident CHD events. In women, after controlling for mean arterial blood pressure averaged over the previous 6 years, diabetes, cigarette smoking, plasma lipid levels, and other risk factors, each SD decrease in the AVR was associated with an increased risk of any incident CHD (relative risk [RR], 1.37; 95% confidence interval [CI], 1.08-1.72) and of acute myocardial infarction (RR, 1.50; 95% CI, 1.10-2.04). In contrast, AVR was unrelated to any incident CHD in men (RR, 1.00; 95% CI, 0.84-1.18) or to acute myocardial infarction (RR, 1.08; 95% CI, 0.85-1.38). Conclusion  Retinal arteriolar narrowing is related to risk of CHD in women but not in men, supporting a more prominent microvascular role in the development of CHD in women than in men. Future work is needed to confirm these findings.      

Estrogen and progestin, lipoprotein(a), and the risk of recurrent coronary heart disease events after menopause

Context  Lipoprotein(a) [Lp(a)] has been identified as an independent risk factor for coronary heart disease (CHD) events. However, few data exist on the clinical importance of Lp(a) lowering for CHD prevention. Hormone therapy with estrogen has been found to lower Lp(a) levels in women. Objective  To determine the relationships among treatment with estrogen and progestin, serum Lp(a) levels, and subsequent CHD events in postmenopausal women. Design and Setting  The Heart and Estrogen/progestin Replacement Study (HERS), a randomized, blinded, placebo-controlled secondary prevention trial conducted from January 1993 through July 1998 with a mean follow-up of 4.1 years at 20 centers. Participants  A total of 2763 postmenopausal women younger than 80 years with coronary artery disease and an intact uterus. Mean age was 66.7 years. Intervention  Participants were randomly assigned to receive either conjugated equine estrogens, 0.625 mg, plus medroxyprogesterone acetate, 2.5 mg, in 1 tablet daily (n = 1380), or identical placebo (n = 1383). Main Outcome Measures  Lipoprotein(a) levels and CHD events (nonfatal myocardial infarction and CHD death). Results  Increased baseline Lp(a) levels were associated with subsequent CHD events among women in the placebo arm. After multivariate adjustment, women in the second, third, and fourth quartiles of baseline Lp(a) level had relative hazards (RHs) (compared with the first quartile) of 1.01 (95% confidence interval [CI], 0.64-1.59), 1.31 (95% CI, 0.85-2.04), and 1.54 (95% CI, 0.99-2.39), respectively, compared with women in the lowest quartile (P for trend = .03). Treatment with estrogen and progestin reduced mean (SD) Lp(a) levels significantly (–5.8 [15] mg/dL) (-0.20 [0.53] µmol/L)compared with placebo (0.3 [17] mg/dL) (0.01 [0.60] µmol/L) (P<.001). In a randomized subgroup comparison, women with low baseline Lp(a) levels had less benefit from estrogen and progestin than women with high Lp(a) levels; the RH for women assigned to estrogen and progestin compared with placebo were 1.49 (95% CI, 0.97-2.26) in the lowest quartile and 1.05 (95% CI, 0.67-1.65), 0.78 (0.52-1.18), and 0.85 (0.58-1.25) in the second, third, and fourth quartiles, respectively (P for interaction trend = .03). Conclusions  Our data suggest that Lp(a) is an independent risk factor for recurrent CHD in postmenopausal women and that treatment with estrogen and progestin lowers Lp(a) levels. Estrogen and progestin therapy appears to have a more favorable effect (relative to placebo) in women with high initial Lp(a) levels than in women with low levels. This apparent interaction needs confirmation in other trials.      

Major outcomes in moderately hypercholesterolemic,hypertensive patients randomized to pravastatin vs usual care: The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT-LLT)

Context  Studies have demonstrated that statins administered to individuals with risk factors for coronary heart disease (CHD) reduce CHD events. However, many of these studies were too small to assess all-cause mortality or outcomes in important subgroups. Objective  To determine whether pravastatin compared with usual care reduces all-cause mortality in older, moderately hypercholesterolemic, hypertensive participants with at least 1 additional CHD risk factor. Design and Setting  Multicenter (513 primarily community-based North American clinical centers), randomized, nonblinded trial conducted from 1994 through March 2002 in a subset of participants from the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). Participants  Ambulatory persons (n = 10 355), aged 55 years or older, with low-density lipoprotein cholesterol (LDL-C) of 120 to 189 mg/dL (100 to 129 mg/dL if known CHD) and triglycerides lower than 350 mg/dL, were randomized to pravastatin (n = 5170) or to usual care (n = 5185). Baseline mean total cholesterol was 224 mg/dL; LDL-C, 146 mg/dL; high-density lipoprotein cholesterol, 48 mg/dL; and triglycerides, 152 mg/dL. Mean age was 66 years, 49% were women, 38% black and 23% Hispanic, 14% had a history of CHD, and 35% had type 2 diabetes. Intervention  Pravastatin, 40 mg/d, vs usual care. Main Outcome Measures  The primary outcome was all-cause mortality, with follow-up for up to 8 years. Secondary outcomes included nonfatal myocardial infarction or fatal CHD (CHD events) combined, cause-specific mortality, and cancer. Results  Mean follow-up was 4.8 years. During the trial, 32% of usual care participants with and 29% without CHD started taking lipid-lowering drugs. At year 4, total cholesterol levels were reduced by 17% with pravastatin vs 8% with usual care; among the random sample who had LDL-C levels assessed, levels were reduced by 28% with pravastatin vs 11% with usual care. All-cause mortality was similar for the 2 groups (relative risk [RR], 0.99; 95% confidence interval [CI], 0.89-1.11; P = .88), with 6-year mortality rates of 14.9% for pravastatin vs 15.3% with usual care. CHD event rates were not significantly different between the groups (RR, 0.91; 95% CI, 0.79-1.04; P = .16), with 6-year CHD event rates of 9.3% for pravastatin and 10.4% for usual care. Conclusions  Pravastatin did not reduce either all-cause mortality or CHD significantly when compared with usual care in older participants with well-controlled hypertension and moderately elevated LDL-C. The results may be due to the modest differential in total cholesterol (9.6%) and LDL-C (16.7%) between pravastatin and usual care compared with prior statin trials supporting cardiovascular disease prevention.      

Fish and omega-3 fatty acid intake and risk of coronary heart disease in women

Context  Higher consumption of fish and omega-3 fatty acids has been associated with a lower risk of coronary heart disease (CHD) in men, but limited data are available regarding women. Objective  To examine the association between fish and long-chain omega-3 fatty acid consumption and risk of CHD in women. Design, Setting, and Participants  Dietary consumption and follow-up data from 84 688 female nurses enrolled in the Nurses' Health Study, aged 34 to 59 years and free from cardiovascular disease and cancer at baseline in 1980, were compared from validated questionnaires completed in 1980, 1984, 1986, 1990, and 1994. Main Outcome Measures  Incident nonfatal myocardial infarction and CHD deaths. Results  During 16 years of follow-up, there were 1513 incident cases of CHD (484 CHD deaths and 1029 nonfatal myocardial infarctions). Compared with women who rarely ate fish (<1 per month), those with a higher intake of fish had a lower risk of CHD. After adjustment for age, smoking, and other cardiovascular risk factors, the multivariable relative risks (RRs) of CHD were 0.79 (95% confidence interval [CI], 0.64-0.97) for fish consumption 1 to 3 times per month, 0.71 (95% CI, 0.58-0.87) for once per week, 0.69 (95% CI, 0.55-0.88) for 2 to 4 times per week, and 0.66 (95% CI, 0.50-0.89) for 5 or more times per week (P for trend = .001). Similarly, women with a higher intake of omega-3 fatty acids had a lower risk of CHD, with multivariable RRs of 1.0, 0.93, 0.78, 0.68, and 0.67 (P<.001 for trend) across quintiles of intake. For fish intake and omega-3 fatty acids, the inverse association appeared to be stronger for CHD deaths (multivariate RR for fish consumption 5 times per week, 0.55 [95% CI, 0.33-0.90] for CHD deaths vs 0.73 [0.51-1.04]) than for nonfatal myocardial infarction. Conclusion  Among women, higher consumption of fish and omega-3 fatty acids is associated with a lower risk of CHD, particularly CHD deaths.      

Long-term Intake of Dietary Fiber and Decreased Risk of Coronary Heart Disease Among Women

Context  Epidemiological studies of men suggest that dietary fiber intake protects against coronary heart disease (CHD), but data on this association in women are sparse. Objective  To examine the association between long-term intake of total dietary fiber as well as fiber from different sources and risk of CHD in women. Design and Setting  The Nurses' Health Study, a large, prospective cohort study of US women followed up for 10 years from 1984. Dietary data were collected in 1984, 1986, and 1990, using a validated semiquantitative food frequency questionnaire. Participants  A total of 68,782 women aged 37 to 64 years without previously diagnosed angina, myocardial infarction (MI), stroke, cancer, hypercholesterolemia, or diabetes at baseline. Main Outcome Measure  Incidence of acute MI or death due to CHD by amount of fiber intake. Results  Response rate averaged 80% to 90% during the 10-year follow-up. We documented 591 major CHD events (429 nonfatal MIs and 162 CHD deaths). The age-adjusted relative risk (RR) for major CHD events was 0.53 (95% confidence interval [CI], 0.40-0.69) for women in the highest quintile of total dietary fiber intake (median, 22.9 g/d) compared with women in the lowest quintile (median, 11.5 g/d). After controlling for age, cardiovascular risk factors, dietary factors, and multivitamin supplement use, the RR was 0.77 (95% CI, 0.57-1.04). For a 10-g/d increase in total fiber intake (the difference between the lowest and highest quintiles), the multivariate RR of total CHD events was 0.81 (95% CI, 0.66-0.99). Among different sources of dietary fiber (eg, cereal, vegetables, fruit), only cereal fiber was strongly associated with a reduced risk of CHD (multivariate RR, 0.63; 95% CI, 0.49-0.81 for each 5-g/d increase in cereal fiber). Conclusions  Our findings in women support the hypothesis that higher fiber intake, particularly from cereal sources, reduces the risk of CHD.      

Predictive value for the Chinese population of the Framingham CHD risk assessment tool compared with the Chinese Multi-Provincial Cohort Study

Context  The Framingham Heart Study helped to establish tools to assess coronary heart disease (CHD) risk, but the homogeneous nature of the Framingham population prevents simple extrapolation to other populations. Recalibration of Framingham functions could permit various regions of the world to adapt Framingham tools to local populations. Objective  To evaluate the performance of the Framingham CHD risk functions, directly and after recalibration, in a large Chinese population, compared with the performance of the functions derived from the Chinese Multi-provincial Cohort Study (CMCS). Design, Setting, and Participants  The CMCS cohort included 30 121 Chinese adults aged 35 to 64 years at baseline. Participants were recruited from 11 provinces and were followed up for new CHD events from 1992 to 2002. Participants in the Framingham Heart Study were 5251 white US residents of Framingham, Mass, who were 30 to 74 years old at baseline in 1971 to 1974 and followed up for 12 years. Main Outcome Measures  "Hard" CHD (coronary death and myocardial infarction) was used as the end point in comparisons of risk factors (age, blood pressure, smoking, diabetes, total cholesterol, and high-density lipoprotein cholesterol [HDL-C]) as evaluated by the CMCS functions, original Framingham functions, and recalibrated Framingham functions. Results  The CMCS cohort had 191 hard CHD events and 625 total deaths vs 273 CHD events and 293 deaths, respectively, for Framingham. For most risk factor categories, the relative risks for CHD were similar for Chinese and Framingham participants, with a few exceptions (ie, age, total cholesterol of 200-239 mg/dL [5.18-6.19 mmol/L], and HDL-C less than 35 mg/dL [0.91 mmol/L] in men; smoking in women). The discrimination using the Framingham functions in the CMCS cohort was similar to the CMCS functions: the area under the receiver operating characteristic curve was 0.705 for men and 0.742 for women using the Framingham functions vs 0.736 for men and 0.759 for women using the CMCS functions. However, the original Framingham functions systematically overestimated the absolute CHD risk in the CMCS cohort. For example, in the 10th risk decile in men, the predicted rate of CHD death was 20% vs an actual rate of 3%. Recalibration of the Framingham functions using the mean values of risk factors and mean CHD incidence rates of the CMCS cohort substantially improved the performance of the Framingham functions in the CMCS cohort. Conclusions  The original Framingham functions overestimated the risk of CHD for CMCS participants. Recalibration of the Framingham functions improved the estimates and demonstrated that the Framingham model is useful in the Chinese population. For regions that have no established cohort, recalibration using CHD rates and risk factors may be an effective method to develop CHD risk prediction algorithms suited for local practice.      

Coronary artery calcium score combined with Framingham score for risk prediction in asymptomatic individuals

Context  Guidelines advise that all adults undergo coronary heart disease (CHD) risk assessment to guide preventive treatment intensity. Although the Framingham Risk Score (FRS) is often recommended for this, it has been suggested that risk assessment may be improved by additional tests such as coronary artery calcium scoring (CACS). Objectives  To determine whether CACS assessment combined with FRS in asymptomatic adults provides prognostic information superior to either method alone and whether the combined approach can more accurately guide primary preventive strategies in patients with CHD risk factors. Design, Setting, and Participants  Prospective observational population-based study, of 1461 asymptomatic adults with coronary risk factors. Participants with at least 1 coronary risk factor (>45 years) underwent computed tomography (CT) examination, were screened between 1990-1992, were contacted yearly for up to 8.5 years after CT scan, and were assessed for CHD. This analysis included 1312 participants with CACS results; excluded were 269 participants with diabetes and 14 participants with either missing data or had a coronary event before CACS was performed. Main Outcome Measure  Nonfatal myocardial infarction (MI) or CHD death. Results  During a median of 7.0 years of follow-up, 84 patients experienced MI or CHD death; 70 patients died of any cause. There were 291 (28%) participants with an FRS of more than 20% and 221 (21%) with a CACS of more than 300. Compared with an FRS of less than 10%, an FRS of more than 20% predicted the risk of MI or CHD death (hazard ratio [HR], 14.3; 95% confidence interval [CI]; 2.0-104; P = .009). Compared with a CACS of zero, a CACS of more than 300 was predictive (HR, 3.9; 95% CI, 2.1-7.3; P<.001). Across categories of FRS, CACS was predictive of risk among patients with an FRS higher than 10% (P<.001) but not with an FRS less than 10%. Conclusion  These data support the hypothesis that high CACS can modify predicted risk obtained from FRS alone, especially among patients in the intermediate-risk category in whom clinical decision making is most uncertain.      

Calcification of the aortic arch: risk factors and association with coronary heart disease, stroke, and peripheral vascular disease

Context  Calcium deposits in coronary and extracoronary arterial beds may indicate the extent of atherosclerosis. However, the incremental predictive value of vascular calcification, beyond traditional coronary risk factors, is not clearly established. Objective  To evaluate risk factors for aortic arch calcification and its long-term association with cardiovascular diseases in a population-based sample. Design and Setting  Cohort study conducted at a health maintenance organization in northern California. Participants  A total of 60,393 women and 55,916 men, aged 30 to 89 years at baseline who attended multiphasic health checkups between 1964 and 1973 and for whom incidence of hospitalizations and/or mortality data were ascertained using discharge diagnosis codes and death records through December 31, 1997 (median follow-up, 28 years). Main Outcome Measure  Hospitalization for or death due to coronary heart disease, ischemic stroke, hemorrhagic stroke, or peripheral vascular disease, as associated with aortic arch calcification found on chest radiograph at checkup from 1964-1973. Results  Aortic arch calcification was present in 1.9% of men and 2.6% of women. It was independently associated with older age, no college education, current smoking, and hypertension in both sexes, but it was inversely related to body mass index and family history of myocardial infarction. In women, aortic arch calcification was also associated with black race and elevated serum cholesterol level. After adjustment for age, educational attainment, race/ethnicity, cigarette smoking, alcohol consumption, body mass index, serum cholesterol level, hypertension, diabetes, and family history of myocardial infarction, aortic arch calcification was associated with an increased risk of coronary heart disease (in men, relative risk [RR], 1.27; 95% confidence interval [CI], 1.11-1.45; in women, RR, 1.22; 95% CI, 1.07-1.38). Among women, it was also independently associated with a 1.46-fold increased risk of ischemic stroke (95% CI, 1.28-1.67). Conclusion  In our population-based cohort, aortic arch calcification was independently related to coronary heart disease risk in both sexes as well as to ischemic stroke risk in women.      

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

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.      

Drug treatment of hyperlipidemia in women

Context  Several clinical trials have evaluated the effects of lipid-lowering medications on coronary heart disease (CHD). Many of the trials have not included enough women to allow sex-specific analyses or have not reported results in women separately. Objectives  To assess and synthesize the evidence regarding drug treatment of hyperlipidemia for the prevention of CHD events in women and to conduct a meta-analysis of the effect of drug treatment on mortality. Data Sources  We searched MEDLINE, the Cochrane Database, and the Database of Abstracts of Reviews of Effectiveness for articles published from 1966 through December 2003. We reviewed reference lists of articles and consulted content experts. Study Selection and Data Extraction  Studies of outpatients that had a treatment duration of at least 1 year, assessed the impact of lipid lowering on clinical outcomes, and reported results by sex were included. Outcomes evaluated were total mortality, CHD mortality, nonfatal myocardial infarction, revascularization, and total CHD events. Summary estimates of the relative risks (RRs) with therapy were calculated using a random-effects model for patients with and without a previous history of cardiovascular disease. Data Synthesis  Thirteen studies were included. Six trials included a total of 11 435 women without cardiovascular disease and assessed the effects of lipid-lowering medications. Lipid lowering did not reduce total mortality (RR, 0.95; 95% confidence interval [CI], 0.62-1.46), CHD mortality (RR, 1.07; 95% CI, 0.47-2.40), nonfatal myocardial infarction (RR, 0.61; 95% CI, 0.22-1.68), revascularization (RR, 0.87; 95% CI, 0.33-2.31), or CHD events (RR, 0.87; 95% CI, 0.69-1.09). However, some analyses were limited by too few CHD events in the available trials. Eight trials included 8272 women with cardiovascular disease and assessed the effects of lipid-lowering medications. Lipid lowering did not reduce total mortality in women with cardiovascular disease (RR, 1.00; 95% CI, 0.77-1.29). However, lipid lowering reduced CHD mortality (RR, 0.74; 95% CI, 0.55-1.00), nonfatal myocardial infarction (RR, 0.71; 95% CI, 0.58-0.87), revascularization (RR, 0.70; 95% CI, 0.55-0.89), and total CHD events (RR, 0.80; CI, 0.71-0.91). Conclusions  For women without cardiovascular disease, lipid lowering does not affect total or CHD mortality. Lipid lowering may reduce CHD events, but current evidence is insufficient to determine this conclusively. For women with known cardiovascular disease, treatment of hyperlipidemia is effective in reducing CHD events, CHD mortality, nonfatal myocardial infarction, and revascularization, but it does not affect total mortality.      

Postmenopausal hormone therapy and risk of cardiovascular disease by age and years since menopause

Context  The timing of initiation of hormone therapy may influence its effect on cardiovascular disease. Objective  To explore whether the effects of hormone therapy on risk of cardiovascular disease vary by age or years since menopause began. Design, Setting, and Participants  Secondary analysis of the Women's Health Initiative (WHI) randomized controlled trials of hormone therapy in which 10 739 postmenopausal women who had undergone a hysterectomy were randomized to conjugated equine estrogens (CEE) or placebo and 16 608 postmenopausal women who had not had a hysterectomy were randomized to CEE plus medroxyprogesterone acetate (CEE + MPA) or placebo. Women aged 50 to 79 years were recruited to the study from 40 US clinical centers between September 1993 and October 1998. Main Outcome Measures  Statistical test for trend of the effect of hormone therapy on coronary heart disease (CHD) and stroke across categories of age and years since menopause in the combined trials. Results  In the combined trials, there were 396 cases of CHD and 327 cases of stroke in the hormone therapy group vs 379 cases of CHD and 239 cases of stroke in the placebo group. For women with less than 10 years since menopause began, the hazard ratio (HR) for CHD was 0.76 (95% confidence interval [CI], 0.50-1.16); 10 to 19 years, 1.10 (95% CI, 0.84-1.45); and 20 or more years, 1.28 (95% CI, 1.03-1.58) (P for trend = .02). The estimated absolute excess risk for CHD for women within 10 years of menopause was –6 per 10 000 person-years; for women 10 to 19 years since menopause began, 4 per 10 000 person-years; and for women 20 or more years from menopause onset, 17 per 10 000 person-years. For the age group of 50 to 59 years, the HR for CHD was 0.93 (95% CI, 0.65-1.33) and the absolute excess risk was –2 per 10 000 person-years; 60 to 69 years, 0.98 (95% CI, 0.79-1.21) and –1 per 10 000 person-years; and 70 to 79 years, 1.26 (95% CI, 1.00-1.59) and 19 per 10 000 person-years (P for trend = .16). Hormone therapy increased the risk of stroke (HR, 1.32; 95% CI, 1.12-1.56). Risk did not vary significantly by age or time since menopause. There was a nonsignificant tendency for the effects of hormone therapy on total mortality to be more favorable in younger than older women (HR of 0.70 for 50-59 years; 1.05 for 60-69 years, and 1.14 for 70-79 years; P for trend = .06). Conclusions  Women who initiated hormone therapy closer to menopause tended to have reduced CHD risk compared with the increase in CHD risk among women more distant from menopause, but this trend test did not meet our criterion for statistical significance. A similar nonsignificant trend was observed for total mortality but the risk of stroke was elevated regardless of years since menopause. These data should be considered in regard to the short-term treatment of menopausal symptoms. Trial Registration  clinicaltrials.gov Identifier: NCT00000611      

Exercise type and intensity in relation to coronary heart disease in men

Context  Studies have shown an inverse relationship between exercise and risk of coronary heart disease (CHD), but data on type and intensity are sparse. Objective  To assess the amount, type, and intensity of physical activity in relation to risk of CHD among men. Design, Setting, and Participants  A cohort of 44 452 US men enrolled in the Health Professionals' Follow-up Study, followed up at 2-year intervals from 1986 through January 31, 1998, to assess potential CHD risk factors, identify newly diagnosed cases of CHD, and assess levels of leisure-time physical activity. Main Outcome Measure  Incident nonfatal myocardial infarction or fatal CHD occurring during the follow-up period. Results  During 475 755 person-years, we documented 1700 new cases of CHD. Total physical activity, running, weight training, and rowing were each inversely associated with risk of CHD. The RRs (95% confidence intervals [CIs]) corresponding to quintiles of metabolic equivalent tasks (METs) for total physical activity adjusted for age, smoking, and other cardiovascular risk factors were 1.0, 0.90 (0.78-1.04), 0.87 (0.75-1.00), 0.83 (0.71-0.96), and 0.70 (0.59-0.82) (P<.001 for trend). Men who ran for an hour or more per week had a 42% risk reduction (RR, 0.58; 95% CI, 0.44-0.77) compared with men who did not run (P<.001 for trend). Men who trained with weights for 30 minutes or more per week had a 23% risk reduction (RR, 0.77; 95% CI, 0.61-0.98) compared with men who did not train with weights (P = .03 for trend). Rowing for 1 hour or more per week was associated with an 18% risk reduction (RR, 0.82; 05% CI, 0.68-0.99). Average exercise intensity was associated with reduced CHD risk independent of the total volume of physical activity. The RRs (95% CIs) corresponding to moderate (4-6 METs) and high (6-12 METs) activity intensities were 0.94 (0.83-1.04) and 0.83 (0.72-0.97) compared with low activity intensity (<4 METs) (P = .02 for trend). A half-hour per day or more of brisk walking was associated with an 18% risk reduction (RR, 0.82; 95% CI, 0.67-1.00). Walking pace was associated with reduced CHD risk independent of the number of walking hours. Conclusions  Total physical activity, running, weight training, and walking were each associated with reduced CHD risk. Average exercise intensity was associated with reduced risk independent of the number of MET-hours spent in physical activity.      

Cost-effectiveness of vitamin therapy to lower plasma homocysteine levels for the prevention of coronary heart disease: effect of grain fortification and beyond

Context  A high homocysteine level has been identified as an independent modifiable risk factor for coronary heart disease (CHD) events and death. Since January 1998, the US Food and Drug Administration has required that all enriched grain products contain 140 µg of folic acid per 100 g, a level considered to decrease homocysteine levels. Objectives  To examine the potential effect of grain fortification with folic acid on CHD events and to estimate the cost-effectiveness of additional vitamin supplementation (folic acid and cyanocobalamin) for CHD prevention. Design and Setting  Cost-effectiveness analysis using the Coronary Heart Disease Policy Model, a validated, state-transition model of CHD events in adults aged 35 through 84 years. Data from the third National Health and Nutrition Examination Survey (NHANES III) were used to estimate age- and sex-specific differences in homocysteine levels. Intervention  Hypothetical comparison between a diet that includes enriched grain products projected to increase folic acid intake by 100 µg/d with the same diet without folic acid fortification; and a comparison between vitamin therapy that consists of 1 mg of folic acid and 0.5 mg of cyanocobalamin and the diet that includes grains fortified with folic acid. Main Outcome Measures  Incidence of myocardial infarction and death from CHD, quality-adjusted life-years (QALYs) saved, and medical costs. Results  Grain fortification with folic acid was predicted to decrease CHD events by 8% in women and 13% in men, with comparable reductions in CHD mortality. The model projected that, compared with grain fortification alone, treating all patients with known CHD with folic acid and cyanocobalamin over a 10-year period would result in 310 000 fewer deaths and lower costs. Over the same 10-year period, providing vitamin supplementation in addition to grain fortification to all men aged 45 years or older without known CHD was projected to save more than 300 000 QALYs, to save more than US $2 billion, and to be the preferred strategy. For women without CHD, the preferred vitamin supplementation strategy would be to treat all women older than 55 years, a strategy projected to save more than 140 000 QALYs over 10 years. Conclusions  Folic acid and cyanocobalamin supplementation may be cost-effective among many population subgroups and could have a major epidemiologic benefit for primary and secondary prevention of CHD if ongoing clinical trials confirm that homocysteine-lowering therapy decreases CHD event rates.      

Inflammatory biomarkers,hormone replacement therapy,and incident coronary heart disease: prospective analysis from the Women's Health Initiative observational study

Context  Postmenopausal hormone replacement therapy (HRT) has been shown to elevate C-reactive protein (CRP) levels. Several inflammatory biomarkers, including CRP, are associated with increased cardiovascular risk. However, whether the effect of HRT on CRP represents a clinical hazard is unknown. Objectives  To assess the association between baseline levels of CRP and interleukin 6 (IL-6) and incident coronary heart disease (CHD) and to examine the relationship between baseline use of HRT, CRP, and IL-6 levels as they relate to subsequent vascular risk. Design, Setting, and Participants  Prospective, nested case-control study of postmenopausal women, forming part of the Women's Health Initiative, a large, nationwide, observational study. Among 75 343 women with no history of cardiovascular disease or cancer, 304 women who developed incident CHD were defined as cases and matched by age, smoking status, ethnicity, and follow-up time with 304 study participants who remained event free during a median observation period of 2.9 years. Main Outcome Measure  Incidence of first myocardial infarction or death from CHD. Results  Median baseline levels of CRP (0.33 vs 0.25 mg/dL; interquartile range [IQR], 0.14-0.71 vs 0.10-0.47; P<.001) and IL-6 (1.81 vs 1.47 pg/mL; IQR, 1.30-2.75 vs 1.05-2.15; P<.001) were significantly higher among cases compared with controls. In matched analyses, the odds ratio (OR) for incident CHD in the highest vs lowest quartile was 2.3 for CRP (95% confidence interval [CI], 1.4-3.7; P for trend = .002) and 3.3 for IL-6 (95% CI, 2.0-5.5; P for trend <.001). After additional adjustment for lipid and nonlipid risk factors, both inflammatory markers were significantly associated with a 2-fold increase in odds for CHD events. As anticipated, current use of HRT was associated with significantly elevated median CRP levels. However, there was no association between HRT and IL-6. In analyses comparing individuals with comparable baseline levels of either CRP or IL-6, those taking or not taking HRT had similar CHD ORs. In analyses stratified by HRT, we observed a positively graded relationship between plasma CRP levels and the OR for CHD among both users and nonusers of HRT across the full spectrum of baseline CRP. Conclusions  These prospective findings indicate that CRP and IL-6 independently predict vascular events among apparently healthy postmenopausal women and that HRT increases CRP. However, use or nonuse of HRT had less importance as a predictor of cardiovascular risk than did baseline levels of either CRP or IL-6.