White blood cell count and incidence of coronary heart disease and ischemic stroke and mortality from cardiovascular disease in African-American and White men and women: atherosclerosis risk in communities study

The authors examined the association between white blood cell (WBC) count and incidence of coronary heart disease and ischemic stroke and mortality from cardiovascular disease in 13,555 African-American and White men and women from the Atherosclerosis Risk in Communities (ARIC) Study. Blood was drawn at the ARIC baseline examination, beginning in 1987-1989. During an average of 8 years of follow-up (through December 1996), there were 488 incident coronary heart disease events, 220 incident strokes, and 258 deaths from cardiovascular disease. After adjustment for age, sex, ARIC field center, and multiple risk factors, there was a direct association between WBC count and incidence of coronary heart disease (p < 0.001 for trend) and stroke (p for trend < 0.001) and mortality from cardiovascular disease (p for trend < 0.001) in African Americans. The African Americans in the highest quartile of WBC count (> or =7,000 cells/mm(3)) had 1.9 times the risk of incident coronary heart disease (95% confidence interval (CI): 1.19, 3.09), 1.9 times the risk of incident ischemic stroke (95% CI: 1.03, 3.34), and 2.3 times the risk of cardiovascular disease mortality (95% CI: 1.38, 3.72) as their counterparts in the lowest quartile of WBC count (<4,800 cells/mm(3)). These associations were similar in Whites and in never smokers. An elevated WBC count is directly associated with increased incidence of coronary heart disease and ischemic stroke and mortality from cardiovascular disease in African-American and White men and women.     

Pulmonary function as a predictor of coronary heart disease

The role of pulmonary function as an independent predictor of coronary heart disease was examined in 1965-1983 in a cohort of Japanese-American men. As part of the Honolulu Heart Program, the authors measured pulmonary function in 5,924 men aged 45-68 years who were free of coronary heart disease at baseline examination and followed them for 15-18 years for the development of nonfatal myocardial infarction and fatal coronary heart disease. Per cent predicted forced expiratory volume in one second (%PFEV1) was significantly inversely related to coronary heart disease incidence in the total cohort after adjusting for age (p less than 0.0001) and then for all known coronary heart disease risk factors (p = 0.0004). However, when examined by smoking status, %PFEV1 was a predictor of coronary heart disease only among past and current smokers, and not for men who had never smoked cigarettes (p = 0.36). The association between pulmonary function and coronary heart disease can be explained by cigarette smoking, which leads to both lung impairment and coronary heart disease incidence.     

The relationship of white blood cell count to other cardiovascular risk factors

Baseline data for the 12,866 men from the Multiple Risk Factor Intervention Trial was used to study factors related to white blood cell (WBC) count. White blood cell count was significantly higher in smokers (7853 cells/mm3) and ex-smokers (7091 cells/mm3) who stopped smoking less than one year before than in ex-smokers who stopped more than one year before (6255 cells/mm3) and those who never smoked (6094 cells/mm3). In current cigarette smokers, white blood cell count was significantly related to number of cigarettes smoked, degree of inhalation, and duration of smoking (p less than 0.001 for each). In addition, white blood cell count was higher in non-cigarette smokers who smoked pipes, cigars, or cigarillos than among men who did not smoke tobacco (p less than 0.001). White blood cell count was lower in blacks (by 877 cells/mm3) and Orientals (by 634 cells/mm3) than in whites. Leukocyte count also showed a strong inverse association with high density lipoprotein (HDL)-cholesterol, a positive association with triglycerides independent of cigarette use, and a positive association with low density lipoprotein (LDL)-cholesterol in smokers only. Leukocyte counts were inversely related to total family income and alcohol consumption. We conclude that elevated leukocyte count is independently associated with other risk factors for coronary heart disease (CHD) such as amount and duration of smoking as well as an atherogenic profile, and these relationships should be considered when using white blood cell count as a predictor of coronary heart disease.     

Pipe and cigar smoking and major cardiovascular events, cancer incidence and all-cause mortality in middle-aged British men

BACKGROUND: Pipe and cigar smoking are still regarded by many as less hazardous to health than cigarette smoking. METHODS: Prospective study of 7735 men aged 40-59 years drawn from general practices in 24 British towns with mean follow-up of 21.8 years. The outcome measures include major coronary heart disease (CHD) and stroke events, cancer incidence, and deaths from all causes. RESULTS: There were 1133 major CHD events and 440 stroke events, 919 new cancers and 1994 deaths from all causes in the 7121 men with no diagnosed CHD, stroke, diabetes, or cancer at screening. Compared with never smokers, pipe/cigar smokers (primary and secondary combined) showed significantly higher risk of major CHD events (relative risk [RR] = 1.69, 95% CI: 1.32, 2.14) and stroke events (RR = 1.62, 95% CI: 1.08, 2.41) and of cardiovascular, non-cardiovascular, and total mortality (RR = 1.49, 95% CI: 1.13, 1.96, RR = 1.40, 95% CI: 1.08, 1.83 and RR = 1.44, 95% CI: 1.19, 1.74, respectively), after adjustment for lifestyle and biological characteristics. They also showed a significantly higher incidence of smoking-related cancers (RR = 2.67, 95% CI: 1.70, 4.26), largely due to lung cancer (RR = 4.35, 95% CI: 2.05, 8.94). Overall, the effects in pipe/cigar smokers were intermediate between never-smokers and light cigarette smokers, although risks for lung cancer were similar to light cigarette smokers. CONCLUSION: Pipe and cigar smoking, whether primary or secondary, carries significant risk of smoking-related ill health.     

Coronary artery calcium score and coronary heart disease events in a large cohort of asymptomatic men and women

Coronary artery calcium (CAC), a measure of subclinical coronary heart disease (CHD), may be useful in identifying asymptomatic persons at risk of CHD events. The current study included 10,746 adults who were 22-96 years of age, were free of known CHD, and had their CAC quantified by electron-beam tomography at baseline as part of a preventive medical examination at the Cooper Clinic (Dallas, Texas) during 1995-2000. During a mean follow-up of 3.5 years, 81 hard events (CHD death, nonfatal myocardial infarction) and 287 total events (hard events plus coronary revascularization) occurred. Age-adjusted rates (per 1,000 person-years) of hard events were computed according to four CAC categories: no detectable CAC and incremental sex-specific thirds of detectable CAC; these rates were, respectively, 0.4, 1.5, 4.8, and 8.7 (trend p<0.0001) for men and 0.7, 2.3, 3.1, and 6.3 (trend p=0.02) for women. CAC levels also were positively associated with rates of total CHD events for women and men (trend p<0.0001 each). The association between CAC and CHD events remained significant after adjustment for CHD risk factors. CAC was associated with CHD events in persons with no baseline CHD risk factors and in younger (aged <40 years) and older (aged >65 years) study participants. These findings show that CAC is associated with an increased risk of CHD events in asymptomatic women and men.     

Serum enterolactone concentration and the risk of coronary heart disease in a case-cohort study of Finnish male smokers

The lignan enterolactone produced by the intestinal microflora from dietary precursors has been hypothesized to protect against coronary heart disease. The present study examined the association between serum enterolactone concentration and the risk of coronary heart disease. A prospective case-cohort study was conducted among male smokers randomized to receive a placebo supplement in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (1986-1999). Serum enterolactone concentrations were measured by the gas chromatography-mass spectrometry method in serum collected at trial baseline from 340 men diagnosed with nonfatal myocardial infarction (n = 205) or coronary death (n = 135) during follow-up and from the randomly selected subcohort of 420 subjects. The classic risk factors-adjusted rate ratios for all coronary heart disease events in increasing quintiles of enterolactone were 1.00 (referent), 0.85 (95% confidence interval (CI): 0.51, 1.43), 0.59 (95% CI: 0.35, 1.00), 0.69 (95% CI: 0.40, 1.16), and 0.63 (95% CI: 0.33, 1.11), and the p(trend) was 0.07. For the highest versus the lowest quintile of enterolactone, the rate ratios for nonfatal myocardial infarction and coronary death were 0.67 (95% CI: 0.37, 1.23; p(trend) = 0.10) and 0.57 (95% CI: 0.26, 1.25; p(trend) = 0.18), respectively. In conclusion, only weak support for the association between serum enterolactone concentration and coronary heart disease was found.     

The Troms? heart study: coronary risk factors and their association with living conditions during childhood.

We examined the relation between questionnaire answers concerning living conditions during childhood and coronary risk factors in 7405 men and 7247 women. Poverty during childhood was positively associated with age-adjusted levels (p less than 0.05) of total cholesterol and percentage of current smokers (men only) and negatively associated with body height. When cholesterol was adjusted for age, body mass index, leisure time physical activity, coffee and alcohol consumption, and cigarette smoking there was a significant linear trend in women (p less than or equal to 0.0001) but not in men (p = 0.224). Analysing only subjects born in Troms county, giving a more homogeneous population, the linear trend became significant (p = 0.011) for men also. We conclude that childhood poverty followed by a high standard of living operates, at least partly, as a risk factor for coronary heart disease through conventional risk factors.     

Relationship of neck circumference to cardiovascular risk factors

OBJECTIVE: To determine a relationship between neck circumference (NC) and risk factors for coronary heart disease by evaluating the components of the metabolic syndrome. RESEARCH METHODS AND PROCEDURES: The study group included 561 subjects (231 men and 330 women) who had no known major medical conditions and were not receiving any medication therapy. The subjects were those who attended a family health clinic for any reason between 1998 and December 2001. Main indicators studied included NC, waist circumference, waist-to-hip ratio, body mass index, blood pressure, and lipoprotein, glucose, and uric acid levels. RESULTS: Pearson's correlation coefficients indicated a significant association between NC and body mass index (men, r = 0.71; women, r = 0.81; each, p < 0.0001), waist circumference (men, r = 0.75; women, r = 0.79; each, p < 0.0001), waist-to-hip ratio (men, r = 0.56; women, r = 0.63; each, p < 0.0001), total cholesterol (men, r = 0.50; women, r = 0.66; each, p < 0.0001), low-density lipoprotein-cholesterol (men, r = 0.42; women, r = 0.60; each, p < 0.0001), triglycerides (men, r = 0.48; women, r = 0.49; each, p < 0.0001), glucose (men, r = 0.21, p < 0.001; women, r = 0.44; p < 0.0001), uric acid (men, r = 0.50, p < 0.0001; women, r = 0.60, p < 0.001), and systolic (men, r = 0.53; women, r = 0.69; each, p < 0.0001), and diastolic (men, r = 0.55; women, r = 0.65; each, p < 0.0001) blood pressure. DISCUSSION: Higher NC is correlated positively with the factors of the metabolic syndrome; therefore, it is likely to increase the risk of coronary heart disease.     

Serum triglycerides and risk of coronary heart disease among Japanese men and women

To examine the relation of triglycerides with coronary heart disease among populations with low mean total cholesterol, the authors conducted a 15.5-year prospective study ending in 1997 of 11,068 Japanese aged 40-69 years (4,452 men and 6,616 women with mean total cholesterol = 4.73 mmol/liter and 5.03 mmol/liter, respectively), initially free of coronary heart disease or stroke. There were 236 coronary heart disease events comprising 133 myocardial infarctions, 68 angina pectoris events, and 44 sudden cardiac deaths. The coronary heart disease incidence was greater in a dose-response manner across increasing quartiles of nonfasting triglycerides for both sexes. The multivariate relative risk of coronary heart disease adjusting for coronary risk factors and time since last meal associated with a 1-mmol/liter increase in triglycerides was 1.29 (95% confidence interval (CI): 1.09, 1.53; p = 0.004) for men and 1.42 (95% CI: 1.15, 1.75; p = 0.001) for women. The trend was similar for myocardial infarction, angina pectoris, and sudden cardiac death. The relation of triglycerides with coronary heart disease was not influenced materially by total cholesterol levels or, in a subsample analysis (51% of total sample), by high density lipoprotein cholesterol levels. Nonfasting serum triglycerides predict the incidence of coronary heart disease among Japanese men and women who possess low mean values of total cholesterol. Further adjustment for high density lipoprotein cholesterol suggests an independent role of triglycerides on the coronary heart disease risk.     

Effects of passive smoking in the Multiple Risk Factor Intervention Trial

The Multiple Risk Factor Intervention Trial (MRFIT), conducted in 1973-1982, provided a unique opportunity to study the effect of passive smoking on men whose wives smoke. MRFIT participants who reported at entry that they had never smoked tobacco products were classified according to the smoking status of their wives. Men with wives who smoked had similar mean levels of serum thiocyanate (54.3 vs. 53.9 mumol/liter, p = 0.83) but higher mean levels of expired carbon monoxide (7.7 vs. 7.1 ppm, p = 0.001). Lower levels of pulmonary function (by maximum forced expiratory volume in one second) were also observed in these men (3,493.1 vs. 3,591.9 ml, p = 0.04). The relative risks, for men whose wives smoked compared with men whose wives did not smoke, for the endpoints coronary heart disease death, fatal or nonfatal coronary heart disease event, and death from any cause were 2.11 (p = 0.19, 95% confidence interval (CI) 0.69-6.46), 1.48 (p = 0.13, 95% CI 0.89-2.47), and 1.96 (p = 0.08, 95% CI 0.93-4.11), respectively. When smokers who quit prior to entry were included in the analyses, the relative risks, for men whose wives smoked compared with men whose wives did not smoke, for the above endpoints were 1.45 (p = 0.25, 95% CI 0.77-2.73), 1.19 (p = 0.29, 95% CI 0.85-1.65), and 1.72 (p = 0.01, 95% CI 1.12-2.64), respectively. These relative risk estimates did not change appreciably after adjusting for other baseline risk factors. The results suggest that passive exposure to cigarette smoke may have a deleterious impact on the health of nonsmokers and that nonsmokers may be at an increased risk of death through passive exposure to cigarette smoke.     

Postmenopausal estrogen use and mortality. Results from a prospective study in a defined, homogeneous community

The authors studied the association between postmenopausal estrogen use and mortality from cardiovascular disease, coronary heart disease, cancer, and all causes in a cohort of 1,868 women aged 50-79 years residing in a planned community. After 12 years, the age-adjusted all-cause mortality rate was lower in the 734 postmenopausal estrogen users (14.9/100 women) compared with the 1,134 nonusers (21.5/100 women) (relative risk (RR) = 0.69, 95% confidence interval (Cl) 0.55-0.87). After adjustment for age, systolic blood pressure, social class, fasting plasma cholesterol, fasting plasma glucose, Quetelet index (weight (lbs)/height (in)2 x 100), and cigarette smoking by the Cox model, the relative risk increased to 0.79 (95% Cl 0.62-1.01). Because a postmenopausal estrogen-smoking interaction term was significant (p = 0.025), separate Cox models were run for never, past, and current smokers. In never and current smokers, estrogen was protective for all-cause mortality, with relative risks of 0.67 (95% Cl 0.45-0.99) and 0.62 (95% Cl 0.39-0.98), respectively. However, past smokers were not protected by postmenopausal estrogen use (RR = 1.32, 95% Cl 0.84-2.08). Cause-specific models revealed differences in the association of postmenopausal estrogen use with cardiovascular disease mortality and coronary heart disease mortality that were dependent on smoking status. Postmenopausal estrogen use was strongly protective in current smokers but was associated with increased risk in past smokers. As expected, cancer mortality was increased in smokers. The confidence intervals for the relative risk estimate of postmenopausal estrogen use for cancer mortality in each smoking category included one. Finally, a separate analysis of subsequent three-year mortality in women surviving the first nine years of follow-up revealed reduced death rates only for women using estrogen at both baseline and nine years of follow-up, suggesting both a conservative bias in our data introduced by the large reduction in postmenopausal estrogen use during the study period and the possibility of a stronger protective effect for recent postmenopausal estrogen use.     

海南省成年人吸烟与心血管疾病发病风险的前瞻性研究

目的 探讨海南省成年人吸烟与各类心血管疾病发病风险的关联。方法 利用中英合作项目“中国慢性病前瞻性研究”项目海南省人群数据,剔除基线调查时自报患有冠心病、脑卒中和恶性肿瘤的个体后,纳入基线年龄为30～79岁的研究对象共28 940人,利用Cox回归分析计算非吸烟者、戒烟者和当前吸烟者的心血管疾病发病风险HR值和95%CI。结果 研究人群平均随访6.2年,累积随访177 279人年。随访期间男性1 310人,女性2 200人发病。男性吸烟率（47.0%）远高于女性吸烟率（0.3%）。多因素调整后,与非吸烟者相比,吸烟人群心血管疾病的发病风险有所增加,HR值(95%CI)分别为急性冠心病1.63(1.12～2.38)和缺血性心脏病1.53(1.22～1.91)。在当前吸烟者中,每天吸烟量多于30支的人群急性冠心病、缺血性脑卒中和出血性脑卒中的发病风险最高。结论 吸烟能够增加心血管疾病的发病风险,应基于不同心血管疾病风险制定吸烟者戒烟目标和全人群控烟措施。     

老年人吸烟及戒烟与相关死亡的前瞻性研究

目的：前瞻性探讨男性老年人吸烟及戒烟与烟草有关疾病死亡的相互关系。方法：研究对象为1987年西安市22个军队干休所的全部男性离体干部,共计1268人,基线调查时,388人为不吸烟者,419人为吸烟者,461人为戒烟者。终点指标为全死因和与烟草有关疾病死亡。结果：截止1999年,共观察14163人年,平均随访11年。共死亡299人,943人存活,26人失访。在调整了年龄,血压、体重指数,总胆固醇,甘油三酯、饮酒,体育锻炼和既往病史等因素后,多元Cox生存分析模型显示：既往吸烟与该人群相关死亡的对危险度（95％CI）分别为总死亡1．34（1．02－1．76）、慢性阻塞性肺病（COPD）3．23（0．95－10．91）,肺癌、2．31（0．95－5．61）、冠心病1．60（0．81－3．19）。其死亡危险性随既吸烟量的增多和吸烟年限的延长而升高,存在明确的剂量反应关系。与继续吸烟者相比,戒烟总死亡和冠心病死亡和危险性分别下降56％和93％,但COPD的死亡危险却升高了174％。结论：（1）吸烟是中国男性老年人的主要死因之一,而戒烟降低总死亡和心血管病死亡;（2）戒烟者COPD死亡危险高于继续吸烟者的原因可能与“无病吸烟者作用”和“因病戒烟作用有关。     

Short- and long-term association of serum cholesterol with mortality. The 25-year follow-up of the Finnish cohorts of the seven countries study.

The association of serum cholesterol with cause-specific and all-cause mortality was assessed in a cohort of 1,426 men aged 40-59 years who were free of clinically evident heart disease at baseline (1959). A total of 748 deaths (53 percent of the participants) occurred during the 25-year follow-up period. Men with high serum cholesterol levels at baseline had high mortality due to coronary heart disease during both the early and later parts of the follow-up period. In contrast, the association of serum cholesterol with mortality due to causes other than coronary heart disease changed during follow-up (interaction of cholesterol with follow-up period: p = 0.004). During the first 10 years of follow-up, despite their high coronary mortality, men with high cholesterol levels had lower all-cause mortality (age-adjusted relative risk = 0.71 for serum cholesterol above 5.79 mmol/liter vs. below 5.80 mmol/liter; p = 0.03) because of their low cancer mortality (relative risk = 0.55, p = 0.03) and residual mortality (relative risk = 0.49, p less than 0.01). During the last 15 years of follow-up, cholesterol at baseline was no longer associated with mortality due to causes other than coronary heart disease, and consequently, because of their high coronary mortality, men with high cholesterol levels also had higher all-cause mortality (relative risk = 1.22, p = 0.05). The results suggest that to fully analyze the association of serum cholesterol with all-cause mortality, the follow-up period should be sufficiently long--possibly more than 10 years--and the possibility of a change in the direction of the association studied should always be considered.     

中国成年人吸烟与心血管疾病发病风险的关联及其性别差异分析

目的 分析中国成年人吸烟与不同心血管疾病发病风险的关联及其性别差异。方法 研究对象来自中国慢性病前瞻性研究,基线调查开展于2004年6月至2008年7月,剔除基线自报患有恶性肿瘤、冠心病、脑卒中的个体,最终纳入487 373名研究对象。随访人年数的计算从研究对象完成基线调查时开始,至最早出现以下任一事件的时间为止：心血管疾病（CVD）发病、死亡、失访或2015年12月31日。使用Cox比例风险模型计算吸烟行为特征和心血管疾病发病风险的关联。结果 研究对象平均随访8.9年。随访期间新发缺血性心脏病33 947人,急性冠心病事件6 048人,脑内出血7 794人,脑梗死31 722人。男性吸烟率（67.9%）远高于女性（2.7%）。与非吸烟者相比,吸烟能增加各类CVD结局的发病风险,风险效应值HR值 （95%CI）由大到小依次为急性冠心病事件1.54 （1.43～1.66）、缺血性心脏病1.28 （1.24～1.32）、脑梗死1.18 （1.14～1.22）、脑内出血1.07 （1.00～1.15）。当前吸烟者中,每天吸烟量和开始吸烟年龄与急性冠心病事件风险间的关联存在性别差异（性别交互作用P值分别为0.006、0.011）,主要表现为女性吸烟者风险高于男性。每天吸烟量和开始吸烟年龄与缺血性心脏病、脑内出血和脑梗死之间的关联均未见性别差异（性别交互作用P>0.05）。结论 吸烟能够增加各类CVD的发病风险,而女性吸烟者发生急性冠心病事件的风险远高于男性。     

Rapid reduction in coronary risk for those who quit cigarette smoking

The objective of this study was to determine the rate of the decline in risk of a major coronary event after quitting cigarette smoking. It was a population-based case-control study of men and women aged 35 to 69 years in Newcastle, Australia, and men and women aged 35 to 64 years in Auckland, New Zealand, between 1986 and 1994. Cases were 5,572 people identified in population registers of coronary events and controls were 6,268 participants in independent community-based risk factor prevalence surveys from the same study populations. There was a rapid reduction in risk after quitting cigarette smoking. The risk of suffering a major coronary event for men who were current cigarette smokers was 3.5 (95% CI 3.0–4.0) times higher than the risk for never smokers but this fell to 1.5 (95% CI 1.1–1.9) for men who had quit for 1–3 years. Women who were current cigarette smokers were 4.8 (95% CI 4.0–5.9) times more likely to suffer a major coronary event than never smokers and this fell to 1.6 (95% CI 1.0–2.5) for women who had quit for 1–3 years. Those who had quit cigarette smoking for 4–6 years or more had a similar risk to never smokers. These results reinforce the importance of smoking cessation. The public health message is that the benefit of giving up smoking occurs rapidly.     

Smoking cessation and mortality from cardiovascular disease among Japanese men and women: the JACC Study

To examine the effect of smoking cessation on cardiovascular disease mortality in Asians, the authors conducted a 10-year prospective cohort study of 94,683 Japanese (41,782 men and 52,901 women) aged 40-79 years who were part of the Japan Collaborative Cohort Study for Evaluation of Cancer Risk (JACC Study). During 941,043 person-years of follow-up between 1989-1990 and 1999, 698 deaths from stroke, 348 from coronary heart disease, and 1,555 from total cardiovascular disease occurred in men and 550, 199, and 1,155, respectively, in women. For men, the multivariate relative risks for current smokers compared with never smokers were 1.39 (95% confidence interval (CI): 1.13, 1.70) for stroke, 2.51 (95% CI: 1.79, 3.51) for coronary heart disease, and 1.60 (95% CI: 1.39, 1.84) for total cardiovascular disease. The respective relative risks for women were 1.65 (95% CI: 1.21, 2.25), 3.35 (95% CI: 2.23, 5.02), and 2.06 (95% CI: 1.69, 2.51), with larger excess risks for persons aged 40-64 years than for older persons. The risk decline after smoking cessation occurred for coronary heart disease and total cardiovascular disease within 2 years and for total stroke after 2-4 years. For each endpoint and in both age subgroups of 40-64 and 65-79 years, most of the benefit of cessation occurred after 10-14 years following cessation. Findings imply the importance of smoking cessation at any age to prevent cardiovascular disease in Japanese.     

Serum folate and homocysteine and the incidence of acute coronary events: the Kuopio Ischaemic Heart Disease Risk Factor Study

BACKGROUND: Several, but not all, prospective studies have shown that low folate intakes, low circulating folate concentrations, or high plasma total homocysteine (tHcy) concentrations are associated with an increased risk of coronary artery disease (CAD). OBJECTIVE: We examined the relations of both serum folate and serum tHcy concentrations with acute coronary events in middle-aged men from eastern Finland who had no CAD at baseline. DESIGN: In a population-based prospective cohort study, 1027 men aged 46-64 y were examined in 1991-1993 as part of the Kuopio Ischaemic Heart Disease Risk Factor Study. During an average follow-up of 7.7 y (7900 person-years of follow-up), 114 acute coronary events were observed in 61 men who had no previous history of CAD (n = 810). RESULTS: In a Cox model, compared with men whose serum folate concentrations were in the lowest tertile, those whose concentrations were in the highest tertile had a risk factor-adjusted relative risk of acute coronary events of 0.35 (95% CI: 0.17, 0.73; P = 0.005). Serum tHcy concentrations were not significantly associated with the risk of acute coronary events (for the highest tertile compared with the lowest, adjusted relative risk = 1.03; 95% CI: 0.57, 1.87; P = 0.932). CONCLUSIONS: The results of this prospective cohort study do not support the hypothesis that a high circulating tHcy concentration is a risk factor for acute coronary events in a male population free of prior heart disease. However, they do suggest that moderate-to-high serum folate concentrations are associated with a greatly reduced incidence of acute coronary events.     

Risk factors for long-term coronary prognosis after initial myocardial infarction: the Framingham Study

The role of standard coronary heart disease risk factors in predicting the long-term risk of recurrent coronary events in survivors of myocardial infarction is examined. Of 697 subjects (464 males and 233 females) who experienced an initial myocardial infarction during 30 years of follow-up in the Framingham Study, 459 returned for a baseline examination and were followed for up to 32 years (mean = 9.7 years) for incident reinfarction or coronary death. The Cox proportional hazards model was used to evaluate the relation of postinfarction risk factors with reinfarction and coronary death. Age-adjusted analyses showed the risk of reinfarction to be positively associated with blood pressure and serum cholesterol. Risk of coronary death was strongly associated with blood sugar level, systolic blood pressure, serum cholesterol, heart rate, diabetes, and interim reinfarction. In multivariable analyses, systolic pressure, serum cholesterol, and diabetes were predictive of reinfarction; relative weight was inversely associated with reinfarction. Systolic pressure, serum cholesterol, and the prevalence of diabetes persisted as independent predictors of coronary death. When adjustments were made for the effects of these variables, women were at only half the risk of coronary death compared with men. Higher baseline risk factors in women compared with men may obscure an important survival advantage in women. In persons recovered from an initial myocardial infarction, standard risk factors, particularly systolic pressure, serum cholesterol, and diabetes, remain important determinants of coronary prognosis over many years and warrant attention in preventing subsequent events.     

The relationship of smoking cessation to coronary heart disease and lung cancer in the Multiple Risk Factor Intervention Trial (MRFIT).

The impact of smoking cessation on coronary heart disease (CHD) and lung cancer was assessed after 10.5 years of follow-up in the 12,866 men in the Multiple Risk Factor Intervention Trial (MRFIT). Those men who died of lung cancer (n = 119) were either cigarette smokers at entry or ex-smokers; no lung cancer deaths occurred among the 1,859 men who reported never smoking cigarettes. The risk of lung cancer for smokers, adjusted for selected baseline variables using a Cox proportional hazards model, increased as the number of cigarettes smoked increased (B = 0.0203, SE = 0.0076). There was not the same graded response for CHD among smokers at entry. The risk of CHD death was greater among smokers than nonsmokers (RR = 1.57) (B = -0.0034, S.E. = 0.0048). After one year of cessation, the relative risk of dying of CHD for the quitters as compared to non-quitters (RR = 0.63) was significantly lower even after adjusting for baseline differences and changes in other risk factors. The relative risk for smokers who quit for at least the first three years of the trial was even lower compared to non-quitters (RR = 0.38). However, the relative risk for lung cancer for quitters versus non-quitters was close to 1 both for quitters at 12 months and at three years. These data support the benefits of cessation in relation to CHD and are consistent with other epidemiologic studies which suggest that the lag time for a beneficial effect of smoking cessation on lung cancer may be as long as 20 years.