Risk factors in middle age that predict early and late onset of coronary heart disease

Risk Factors for Early-Onset Versus Late-Onset Coronary Heart Disease (CHD): Systematic Review and Meta-Analysis

AIM

We aimed to systematically compare literature on prevalence of modifiable and non-modifiable risk factors for early compared to late-onset coronary heart disease (CHD).

METHODS

PubMed, CINAHL, Embase, and Web of Science databases were searched (review protocol registered in PROSPERO CRD42020173216). Study quality was assessed using the National Heart, Lung and Blood Institute tool for observational and case-control studies. Review Manager 5.3 was used for meta-analysis. Effect sizes were expressed as odds ratio (OR) and mean differences (MD)/standardised MD (SMD) with 95% confidence intervals (CI) for categorical and continuous variables.

RESULTS

Individuals presenting with early-onset CHD (age <65 years) compared to late-onset CHD had higher mean body mass index (MD 1.07 kg/m2; 95% CI 0.31-1.83), total cholesterol (SMD 0.43; 95% CI 0.23-0.62), low-density lipoprotein (SMD 0.26; 95% CI 0.15-0.36) and triglycerides (SMD 0.50; 95% CI 0.22-0.68) with lower high-density lipoprotein-cholesterol (SMD 0.26; 95% CI -0.42--0.11). They were more likely to be smokers (OR 1.76, 95% CI 1.39-2.22) and have a positive family history of CHD (OR 2.08, 95% CI 1.74-2.48). They had lower mean systolic blood pressure (MD 4.07 mmHg; 95% CI -7.36--0.78) and were less likely to have hypertension (OR 0.47, 95% CI 0.39-0.57), diabetes mellitus (OR 0.56, 95% CI 0.51-0.61) or stroke (OR 0.31, 95% CI 0.24-0.42).

CONCLUSION

A focus on weight management and smoking cessation and aggressive management of dyslipidaemia in young adults may reduce the risk of early-onset CHD.

Association of serum cholesterol with coronary heart disease mortality during 50-year follow-up in ten cohorts of the seven countries study

BACKGROUND AND AIM

The association of serum cholesterol levels with the occurrence of coronary heart disease (CHD) mortality during a follow-up of 50 years was rarely investigated previously. Thus, we took advantage of results at hand in 10 pooled cohorts of men aged 40-59 years from the Seven Countries Study (9063 individuals and 2057 CHD fatal events) and we assessed this.

METHODS AND RESULTS

Cox proportional hazards models were run with CHD fatal events (as dependent variable) and cholesterol levels (as independent variables) at years 0, 10, and 25 (in 5 cohorts). Cumulative events during subsequent decades (cumulative approach: CA) and separately in each subsequent decade (partitioned approach: PA) were analyzed. The ecological correlation of average baseline serum cholesterol levels with CHD mortality was very high (R = 0.97). Serum cholesterol and CHD mortality for 50 years were associated at the individual level, and the association estimated by the Cox's coefficients (and related hazards ratios) was initially strong in both CA and PA, but slightly declined during later decades. Hazards ratios (for a difference of 40 mg/dl) ranged from 1.39 to 1.20 for CA and from 1.39 to 0.80 for PA. Coefficients were larger for CA than for PA and the decline was more evident for the latter. Partitioned coefficient became negative and significant in the last decade (from year 40-50). Coefficients derived from cholesterol levels measured at year 10 of follow-up showed similar trends but their magnitude was smaller.

CONCLUSION

Thus, the relationship of serum cholesterol levels with CHD mortality remained relatively stable during at least 40 years after a single cholesterol measurement at baseline in middle-aged men.

The triglyceride paradox in the mortality of coronary artery disease

Background

The role of triglyceride (TG) in secondary prevention of patients with coronary artery disease (CAD) was debated. In the present study, we assessed the association between admission TG levels and long-term mortality risk in CAD patients.

Methods

A retrospective analysis was conducted from a single registered database. 3061 consecutive patients with CAD confirmed by coronary angiography were enrolled and were grouped into 3 categories by the tertiles of admission serum TG levels. The primary end point in this study was all-cause mortality and the secondary end point was cardiovascular mortality.

Results

The mean follow-up time was 26.9 ± 13.6 months and death events occurred in 258 cases and cardiovascular death events occurred in 146 cases. Cumulative survival curves indicated that the risk of all-cause death decreased with increasing TG level (Tertile 1 vs. Tertile 2 vs. Tertile 3 = 10.3% vs. 8.6% vs. 6.3%, log rank test for overall p = 0.001). Cox regression analysis showed an independent correlation between TG level and risk of all-cause mortality [hazard ratio (HR) 0.71, 95% confidence interval (CI) 0.58–0.86] and cardiovascular mortality (HR 0.67, 95% CI 0.51–0.89) in total patients with CAD. Subgroup analysis found the similar results in patients with acute coronary syndrome and acute myocardial infarction.

Conclusions

This study found an inverse association between TG levels and mortality risk in CAD patients, which suggests that the “TG paradox” may exist in CAD patients.

Trial registration

ChiCTR, ChiCTR-OOC-17010433. Registered 17 February 2017 - Retrospectively registered.

Association of hypertension with coronary artery disease onset in the Lebanese population

The onset of coronary artery disease (CAD) is influenced by cardiovascular risk factors that often occur in clusters and may build on one another. The objective of this study is to examine the relationship between hypertension and CAD age of onset in the Lebanese population. This retrospective analysis was performed on data extracted from Lebanese patients (n = 3,753). Logistic regression examined the association of hypertension with the age at CAD diagnosis after controlling for other traditional risk factors. The effect of antihypertensive drugs and lifestyle changes on the onset of CAD was also investigated. Results showed that hypertension is associated with late onset CAD (OR=0.656, 95% CI=0.504-0.853, p=0.001). Use of antihypertensive drugs showed a similar association with delayed CAD onset. When comparing age of onset in CAD patients with traditional risk factors such as hypertension, diabetes, hyperlipidemia, obesity, smoking and family history of CAD, the age of onset was significantly higher for patients with hypertension compared to those with any of the other risk factors studied (p < 0.001). In conclusion, hypertension and its treatment are associated with late coronary atherosclerotic manifestations in Lebanese population. This observation is currently under investigation to clarify its genetic and/or environmental mechanisms.

Increased predictive ability of BMI but not other risk factors with time in men: 39-year follow-up of total mortality in the Oslo Study

OBJECTIVE

Risk factor associations to mortality may change, in part due to removal of high-risk persons. We compared strengths of association and ability of risk factors to predict total mortality across short (<15 years), medium (15-29 years) and long (30-39 years) follow-up.

METHODS

Cardiovascular risk factors were measured in 1972-1973 in the Oslo Study among 14,846 men born in 1923-1932. Relationships of risk factors to mortality (to 2011) were analyzed using Cox regression models, and receiver operating characteristics (ROC) were estimated.

RESULTS

BMI was the only factor that increased strength of association with elapsed time (hazard ratio for ≥35 kg/m(2) vs. 22.5-24.9 kg/m(2): 1.25 (95% CI 0.73-2.17), 1.51 (95% CI 1.06-2.16) and 3.73 (95% CI 2.33-5.98) for <15, 15-29 and 30-39 years, respectively). Other factors lost predictive ability with time. Cigarette smoking was the strongest predictor in all periods. Serum lipids and systolic blood pressure increased risk in most periods, and moderate physical activity was protective to 29 years, but these factors and BMI contributed minimally to ROC.

DISCUSSION

Risk factors differed in association strengths and ability to predict mortality over four decades. BMI strengthened its association with time, while cigarette smoking was strongest in all periods.

Association of coronary heart disease mortality with risk factors according to length of follow-up and serum cholesterol level in men: the Oslo Study cohort

AIM

We aimed to clarify the strength of the association between conventional and metabolic risk factors to coronary heart disease (CHD) mortality across short, intermediate, and long periods of follow-up and whether the effects of risk factors are heterogeneous across serum cholesterol levels.

METHODS

The Oslo Study prospective cohort of 14,846 men aged 40-49 years was followed from screening in 1972-73 until 2006, during which time 1655 subjects died of CHD. Multivariate-adjusted Cox proportional models compared hazard ratios (HRs) and 95% confidence intervals (CIs) for CHD mortality across 0-12, 12-24, and 24-33 years of follow-up. Interactions between risk factors and quartile level of total serum cholesterol were assessed.

RESULTS

Total cholesterol, blood pressure, and cigarette smoking were associated with CHD mortality in multivariate analyses across all follow-up periods. Nonfasting triglyceride levels were associated with CHD in multivariate analyses (0-12 years, HR 1.12, 95% CI 1.00-1.25; 12-24 years, HR 1.13, 95% CI 1.04-1.23; 24-33 years, HR 1.09, 95% CI 1.00-1.19; 0-33 years, HR 1.10, 95% CI 1.05-1.16). A metabolic risk factor score (based on blood pressure, triglycerides, body mass index, and glucose) retained predictivity across all periods. The relations between systolic blood pressure, triglycerides, and metabolic risk factor score to CHD were stronger in the lower than the upper quartiles of serum cholesterol (p < 0.001).

CONCLUSIONS

Conventional risk factors and nonfasting triglycerides increased CHD mortality across all periods of follow-up. The association with metabolic variables was strongest in men with low total cholesterol levels supporting the idea that lowering cholesterol should be the primary target of primary prevention.

The atherogenic and metabolic impact of non-HDL cholesterol versus other lipid sub-components among non-diabetic and diabetic Saudis

Background

Several trials from different populations have reported that non-high density lipoprotein cholesterol (non-HDL-C) has more predictive power than low-density lipoprotein cholesterol (LDL-C) in detecting coronary heart disease (CHD) and none in any Arab community whose propensity to develop CHD is higher compared to other ethnicities. This study aims to determine and compare the impact of non-HDL-C versus other lipid parameters, in predicting coronary heart disease among diabetic versus non-diabetic adult Saudis and identify the lipid parameters which make a significant contribution in the development of coronary heart disease, diabetes mellitus, and metabolic syndrome. 733 adult Saudis were recruited and divided into groups of diabetics and non-diabetics. Each participant completed a questionnaire, underwent physical exam including 12-L ECG, and submitted a fasting blood sample where glucose and lipid parameters were analyzed using routine procedures.

Results

462 subjects (age 45.03 ± 11.52; BMI 28.91 ± 6.07) were classified non-diabetics while the remaining 271 (age 52.73 ± 11.45, BMI 30.15 ± 6.62) were diabetics. 99 out of 465 (21.3%) of non-diabetics had CHD and 114 out of 271 (52.5%) in the diabetics. Non-HDL cholesterol was the best predictor among the non-diabetics (odds-ratio 2.89, CI 1.10–7.58, p-0.03). Total cholesterol was the highest single predictor for the development of CHD among the lipids (odds-ratio 1.36, CI 0.68–2.71, p-0.39) but HDL-cholesterol although small was significant (odds-ratio 0.52, CI 0.27–0.99, p-0.05).

Conclusion

This study supports the use of non-HDL cholesterol as the more practical and reliable target for lipid lowering therapy among the Saudi population.

Predictiveness of body mass index for fatal coronary heart disease in men according to length of follow-up: a 21-year prospective cohort study

AIMS

To test the association between body mass index (BMI) and other coronary risk factors and the risk of a fatal coronary heart disease (CHD) event in different time periods during follow-up.

METHODS

Prospective cohort study with a 21 year follow-up period. A screened sample of 14,403 men aged 40-49 years initially free of CHD. Risk of fatal CHD was calculated for 21 years' cumulative follow-up and for four consecutive 5-year periods.

RESULTS

After adjustment for age and the other risk factors, total cholesterol and systolic blood pressure retained their predictive strength for CHD mortality throughout follow-up. Though cigarette smoking remained a significant predictor, the relative risk decreased with time (test of trend: p=0.01). Intermediate to vigorous physical activity at leisure was protective for 10 years of follow-up and a question on mental stress for 5 years. The test of trend indicated that the risk associated with BMI increased with the duration of follow-up (p=0.002).

CONCLUSIONS

Our data show that coronary risk factors predicted CHD mortality differently according to the length of follow-up, and suggest that the harm associated with obesity may take more than a decade to become evident, in contrast to the classical CHD risk factors.

Short and long term association of a single serum cholesterol measurement in middle-aged men in prediction of fatal coronary and other cardiovascular events: a cross-cultural comparison through Europe

AIMS

The purpose was to study the association of a single serum cholesterol measurement with early and late coronary and other cardiovascular deaths during 35 years of follow-up in samples of men aged 40-59 years in five European countries.

METHODS AND RESULTS

A single serum total cholesterol measurement was considered in samples from Finland (N = 1563), the Netherlands (N = 811), Italy (N = 1642), Serbia (N = 1537) and Greece (N = 1158) (total = 6711). Seven partitioned proportional hazards models were solved, one for each of seven independent 5-year blocks, to predict coronary, stroke, cardiovascular disease and all-cause mortality risk. Partitioned hazard scores were cumulated. The resulting curves showed a relatively constant strength in risk for coronary deaths as a function of baseline serum cholesterol levels, although a strong relationship during the first 10-year period was followed by a weaker relationship later on. The pooled estimates for the five countries gave a relative risk for 1 mmol/l of serum cholesterol (95% confidence intervals) of 1.44 (1.23-1.68) for the first period; 1.52 (1.31-1.76) for the second period; and 1.16 (1.02-1.32) for the third period; 1.18 (1.05-1.32) for the forth period; 1.17 (1.05-1.31) for the fifth period; 1.22 (1.10-1.35) for the sixth period; 1.18 (1.05-1.32) for the seventh 5-year period of follow-up. No significant relationship were found between serum cholesterol and stroke and all-cause mortality, while intermediate findings were obtained for cardiovascular diseases.

CONCLUSION

A single serum cholesterol measurement in middle aged-men maintains a strong relationship with the occurrence of coronary heart disease (CHD) deaths during 35 years of follow-up.

The role of a baseline casual blood pressure measurement and of blood pressure changes in middle age in prediction of cardiovascular and all-cause mortality occurring late in life

OBJECTIVE

The first objective was to study the long-term association of a casual measurement of systolic blood pressure (SBP) with cardiovascular deaths (CVD) and all causes of death (ALL) occurring during 35 years of follow-up in different population samples of men aged 40-59 years in five European countries. The second objective was to study the predictive power of early change in SBP levels (years 0-10) in relation to late fatal events (years 10-35).

DESIGN, SETTING AND PARTICIPANTS

A single measurement of SBP was considered in cohorts in Finland, The Netherlands, Italy, Serbia and Greece for a total of 6507 men. Three partitioned proportional hazards models were solved, one for each independent and subsequent time block of 10 years, after excluding data from the first 5 years, to predict the risk of cardiovascular disease deaths of atherosclerotic origin (CVD) and all cause mortality (ALL). Independently, the predictive power of SBP changes (Delta-SBP) occurred during the first 10 years of follow-up was explored as a possible additional risk factor in relation to CVD and ALL deaths occurring between year 10 and year 35 of follow-up.

RESULTS

Partitioned hazard scores derived from the three partitioned functions were cumulated. The resulting curves showed a continuous and significant association of baseline SBP with CVD and ALL deaths during three decades, although the strength of association declined significantly from the first to the third decade. The relative risk for 20 mmHg of SBP (and its 95% confidence intervals) in predicting CVD deaths was 1.65 (1.54-1.77) for the first 10-year block; 1.33 (1.24-1.42) for the second block; and 1.22 (1.13-1.31) for the last 10-year block. The corresponding levels of ALL deaths were 1.41 (1.34-1.49), 1.26 (1.19-1.32) and 1.11 (1.05-1.17). Changes in SBP during 10 years (Delta-SBP) added predictive power to baseline measurements in a direct and significant way, with a relative risk for a change of 10 mmHg of 1.14 (1.10-1.17) for CVD deaths and 1.11 (1.09-1.13) for ALL deaths.

CONCLUSION

A single measurement of systolic blood pressure in middle-aged men maintains a strong relationship with fatal CVD and ALL deaths during the next 35 years, although for late events the strength of the association definitely declines. Changes in systolic blood pressure levels during the first 10 years of follow-up add predictive power, while baseline measurements retain their predictive power.

Coronary risk factors predicting early and late coronary deaths

OBJECTIVE

To study the time related association of a single measurement of coronary risk factors with coronary heart disease (CHD) deaths occurring during a very long follow up period in a population sample of middle aged men.

DESIGN, SETTING, AND METHODS

Age, systolic blood pressure, serum total cholesterol, physical activity at work, body mass index, and cigarette smoking were measured once in 1622 CHD-free men aged 40-59 belonging to the Italian rural cohorts of the seven countries study. During 35 years of follow up 214 men died from CHD (sudden death and definite myocardial infarction). Seven partitioned proportional hazards models were solved, one for each independent five year block of follow up, to predict the risk of CHD death.

RESULTS

The seven, five year partitioned hazard functions were cumulated and smoothed for each risk factor. The resulting curves showed a regularly increasing time trend in risk for coronary deaths as a function of age, serum cholesterol, systolic blood pressure, and cigarette smoking and a regularly decreasing risk for physical activity. The curves fit straight lines, with large squared correlation coefficients ranging from 0.92-0.97. This suggests a relatively constant strength in the association of risk factor levels with events, which are predicted whatever the length of time after risk factors were measured. These findings were not altered by adding to the models risk factor changes preceding the quinquennium of death.

CONCLUSION

A single measurement of some coronary risk factors in middle aged men maintains a regular and almost monotonic relation with the occurrence of CHD deaths during 35 years of follow up.

Serum albumin and risk of myocardial infarction and all-cause mortality in the Framingham Offspring Study

BACKGROUND

Coronary disease remains the leading cause of death in the United States. The association between serum albumin and cardiovascular disease remains controversial. We used data collected prospectively from participants of the Framingham Offspring Study to assess whether a lower concentration of serum albumin was associated with an increased risk of myocardial infarction (MI) and all-cause mortality.

METHODS AND RESULTS

During 21.9 years of mean follow-up, 280 cases of MI occurred. From the highest to the lowest tertile of serum albumin, crude incidence rates of MI were 26.7, 46.7, and 67.8 cases per 10 000 person-years, respectively, for men and 5.9, 15.0, and 16.8 cases per 10 000 person-years, respectively, for women. In a Mantel-Haenszel method adjusting for age, total cholesterol, and hypertension, lower serum albumin was associated with an increased risk of MI in both sexes. From the highest to the lowest tertile of albumin, the adjusted hazard ratios (95% CI) of MI were 1.0 (reference), 1.25 (0.84 to 1.84), and 1.49 (1.01 to 2.21), respectively, for men and 1.0, 1.79 (0.88 to 3.65), and 2.12 (1.06 to 4.27), respectively, for women. The albumin-MI association was stronger among hypertensive subjects in both sexes. In addition, low albumin was associated with an increased rate of all-cause mortality in women.

CONCLUSIONS

Lower serum albumin concentrations appear to be associated with an increased risk of coronary disease in both sexes and with all-cause mortality in women and could help along with traditional risk factors in identifying people at risk of MI.

Coronary artery calcification in older adults with minimal clinical or subclinical cardiovascular disease

BACKGROUND

Coronary artery calcification (CAC) reflects the extent of coronary artery atherosclerosis. The extent of coronary artery calcification is not well described in older adults.

OBJECTIVE

To determine the extent of CAC in older adults participating in a large population study of cardiovascular disease (CVD), especially those characterized as having minimal clinical or subclinical cardiovascular disease.

DESIGN

An observational epidemiologic study.

POPULATION

Participants in the Cardiovascular Health Study Cohort, mean age 78 years, who had electron beam computed tomography (EBT) scan of the heart (n = 133); included were 106 persons with no prior evidence of clinical or subclinical CVD.

MEASUREMENTS

Total CAC score was measured using cardiac EBT. Cardiovascular disease and risk factors, as well as carotid ultrasound, electrocardiogram, echocardiogram, and ankle-arm index, had been measured previously to define subclinical disease. Previous cerebral magnetic resonance imaging was also evaluated.

RESULTS

Overall, the CAC scores were higher in those with clinical cardiovascular disease or evidence of subclinical cardiovascular disease than in those with no evidence of disease. For the 106 participants without evidence of clinical or subclinical disease, the median score was 176, compared with 367 in those with subclinical disease and 923 in those with clinical CVD. Seventeen persons had scores of zero. There was little difference in risk factors across quartiles of CAC in the subgroup of 106 with prior characterization of minimal CVD despite the broad range of CAC scores. There was a higher proportion of those with white matter grade > or = 2 by magnetic resonance imaging among those with higher CAC scores (P = .025). Infarct-like lesions prevalence ranged from 12.5% in the lowest group to 47.1% in the highest CAC group (P = .019).

CONCLUSIONS

Older adults with evidence of clinical or subclinical CVD have higher total CAC scores. Though the extent of coronary artery calcification was lower in those with minimal evidence of CVD, the range was broad and not explained by CVD risk factors.

Smoking and mortality in an older Chinese cohort

OBJECTIVES

Only limited data are available regarding smoking and health in later life and, in particular, in the older Chinese population. This paper reports the relationship between smoking and mortality in a Chinese cohort aged 70 years and older.

SETTING

A population-based study conducted in Hong Kong.

PARTICIPANTS

A cohort comprising 2030 subjects aged 70 and older were assembled in 1991-1992 and followed for 36 months.

DESIGN

A prospective cohort study.

MEASUREMENTS

Baseline information regarding smoking status as well as several social and health variables were obtained through face-to-face interview at the respondent's place of residence. The outcome variables were mortality from all causes as well as from cancer and cardiovascular and respiratory diseases. Causes of death were ascertained from death certificates.

RESULTS

The prevalence rates of smoking at baseline were 24.9% in men and 8.2% in women. A total of 534 deaths occurred during the 36-month follow-up period. Of these, 447 were attributable to three main causes: cancer, cardiovascular disease, and respiratory disease. Elevated mortality risks from all causes were observed among both male (RR = 1.4; 95% CI, 0.9-1.9) and female (RR = 1.6; 95% CI, 1.0-2.5) current smokers, but the 95% confidence intervals overlapped. Significant association between current smoking and combined mortality from these three major causes was found in men; it was also found in women after excluding those with these diseases at baseline. More than a 3-fold increased risk of cancer mortality was found in current smokers of both sexes. Although nonsignificant associations were found between former smokers and mortality risks in men, women who were former smokers had increased mortality risks from all causes as well as from cancer and respiratory diseases.

CONCLUSIONS

This 3-year prospective study of an older Chinese cohort reveals the impact of smoking on health during later life, especially in women. Smoking cessation, particularly in older men, should be beneficial in reducing mortality. Smoking cessation should begin as early as possible for women.

The effect of age on risk factors for ischemic heart disease: the Manitoba Follow-Up Study, 1948-1993

PURPOSE

The purpose of this paper is to determine the age-specific relationships between risk factors at age 40 through 75 years and ischemic heart disease (IHD), and to determine the effects of aging on these relationships in a cohort of 3983 Canadian males.

METHODS

The Manitoba Follow-Up Study is the prospective investigation of cardiovascular disease as it develops in a cohort of 3983 young men. Over a period of 45 years, from 1948 to 1993, 1094 study members (27%) developed clinical evidence of IHD. Blood pressure, body weight, smoking, and presence of diabetes mellitus have been recorded at regular intervals throughout the follow-up period. Using measurements from examinations every 5 years between ages 40 and 75 years, age-specific Cox proportional hazard models were fit to relate these risk factors to IHD.

RESULTS

The adjusted relative risk of IHD for systolic blood pressure, diastolic blood pressure and smoking were found to significantly (p < 0.001) decline with advancing age. The adjusted relative risk for body mass index and presence of diabetes mellitus for ischemic heart disease did not vary with age (p > 0.05). After age 65 years, these risk factors were of little value for the prediction of IHD.

CONCLUSIONS

The relative risk and statistical significance of blood pressure and smoking, as risk factors for IHD, decline with age.

Plasminogen activator inhibitor-1 (PAI-1) antigen plasma levels in subjects attending a metabolic ward: relation to polymorphisms of PAI-1 and angiontensin converting enzyme (ACE) genes

Plasminogen activator inhibitor 1 (PAI-1) is a determinant of vascular events. Subjects in metabolic wards are at high risk for these events. The renin-angiotensin system modulates plasma PAI-1 levels. An insertion (4G)/deletion (5G) polymorphism is involved in the regulation of the circulating levels of PAI-1. We have evaluated the levels of plasma PAI-1 in 208 individuals from our metabolic ward and correlated these levels with the 4G/5G genotype as well as with a genotype (homozygosity for a deletion polymorphism, DD genotype) of the angiotensin-converting enzyme (ACE) gene. Homozygosity for the insertion genotype (5G/5G) was associated with PAI-1 levels lower than those associated with the deletion genotype (4G/4G) (26.2x/:1.6 versus 33.7x/:1.7 ng/mL, P = .036). Plasma PAI-1 levels appeared to depend on the genotype (P = .014) as much as on age (P = .044), t-PA (P = .0001), or triglyceride levels (P = .005). The association between triglycerides and PAI-1 was significant in subjects carrying the 4G/4G and the 4G/5G genotypes (P = .013 and .036, respectively) but not in those with the 5G/5G genotype. When stratified according to PAI-1 and ACE genotypes, individuals homozygous for both deletions (4G/4G-DD genotypes) exhibited higher plasma PAI-1 levels compared with those of individuals without such homozygosities. However, this difference did not reach statistical significance. We conclude that in a group of subjects from a metabolic ward, a 4G/5G polymorphism of the PAI-1 gene exerts effects on plasma PAI-1 antigen levels comparable to those of established determinants. The association between triglycerides and plasma PAI-1 levels is genotype dependent. A trend to a positive interaction between ACE DD and PAI-1 4G/4G in the regulation of circulating plasma PAI-1 levels is present in this setting.

The role of the apolipoprotein E polymorphism in the prediction of coronary artery disease age of onset

We investigated the role of the apolipoprotein (Apo) E polymorphism in the prediction of CAD age of onset in a sample of unrelated living male (n = 65) and female (n = 54) Caucasian subjects diagnosed with CAD. Cumulative distributions of age at the first diagnosis of CAD were estimated for each Apo E genotype and tested for homogeneity using the log-rank test. The Apo epsilon 33 genotype was used as a reference group for all hypothesis tests. Analyses were performed separately in males and females. We found evidence suggesting that the presence of the Apo epsilon 32 genotype in males is associated with a significantly earlier CAD age of onset. These results suggest that the Apo E polymorphism may be a gender-specific predictor of CAD age of onset.

Long-term Treatment With Pravastatin Alone and in Combination With Gemfibrozil in Familial Type IIB Hyperlipoproteinemia or Combined Hyperlipidemia

BACKGROUND: Pravastatin inhibits 3-hydroxy-3-methylglutaryl-coenzyme A reductase. It prevents mevalonate synthesis, reducing endogenous cholesterol production, and reduces cholesterol content in the liver, thus resulting in a down-regulation of low-density lipoprotein receptor production. Gemfibrozil reduces very low-density lipoprotein production and low-density lipoprotein-cholesterol level and increases very low-density lipoprotein catabolism. Therefore, it was suggested that combination therapy with both drugs could effect greater reduction of cholesterol levels as compared to pravastatin alone. The present study was carried out to evaluate the efficacy and safety of pravastatin as a monotherapy or in combination with gemfibrozil in the treatment of patients with familial type IIb hyperlipoproteinemia or familial combined hyperlipidemia. METHODS AND RESULTS: Forty-one patients were included in the study. All patients initially followed 6 weeks of hypolipidemic diet; subsequently they were randomized and received either 20 mg once daily of pravastatin alone (n = 13) or 20 mg of pravastatin together with 600 mg of gemfibrozil twice daily (n = 14). As a control, 14 patients were treated with diet only. The treatment lasted 24 months and clinical evaluation and laboratory tests were done at given time points. Both groups of treated patients showed an early reduction (3 months) of total (about 30% P <.01 vs controls), low-density lipoprotein (about 35%, P <.01 vs controls) and very low-density lipoprotein cholesterol levels (about 18%, P = NS). In contrast, high-density lipoprotein cholesterol levels increased significantly in patients treated with pravastatin and gemfibrozil (about 20%, P <.05 vs controls). Pravastatin treatment alone reduced the level of serum triglycerides as efficiently as in combination with gemfibrozil. Data showed a sustained normalization of lipid profile until 24 months. However, this effect was achieved in patients that had rather low levels of triglycerides. During the treatment we did not observe any difference in the incidence of possible drug-related side effects. Severe myopathy or rhabdomyolysis was not observed at the doses of the drugs used in our study. CONCLUSIONS: Therapy with pravastatin and in combination with gemfibrozil resulted in significant and sustained normalization of lipid profile in high-risk patients with familial type IIb hyperlipoproteinemia or familial combined hyperlipidemia.

Hypertriglyceridemia and elevated lipoprotein(a) are risk factors for major coronary events in middle-aged men

Cardiovascular risk factors were analyzed in 4,849 male participants, aged 40 to 65 years, in an 8-year follow-up of the Münster Heart Study (Prospective Cardiovascular Münster Study; PROCAM). One hundred eighty-one definite nonfatal myocardial infarctions, 49 fatal myocardial infarctions, and 28 sudden cardiac deaths were observed. Multiple logistic function analysis confirmed that age, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, systolic blood pressure, cigarette smoking, diabetes mellitus, angina pectoris, and family history of myocardial infarction were important cardiovascular risk factors. Interestingly, this analysis revealed a significant and independent association between serum levels of triglycerides and the incidence of major coronary events. The relation between lipoprotein(a) [Lp(a)] levels and the occurrence of major coronary events was analyzed in a subgroup of 878 men. Thirty-three probands with major coronary events had significantly higher geometric mean levels of Lp(a) than 828 men who did not experience major coronary events (0.09 vs 0.05 g/L; p <0.011). Thus, in addition to established risk for factors, serum levels of triglycerides and Lp(a) are sensitive indicators of increased risk major coronary events.

Serum albumin and physical function as predictors of coronary heart disease mortality and incidence in older persons

The role of traditional risk factors in predicting coronary heart disease (CHD) among men and women aged 65 years and over has been extensively debated, but the search for risk factors that are distinctive in the elderly is still ongoing. The relation of serum albumin levels and physical disability to risk of CHD morality and incidence was prospectively assessed in a cohort of 4116 men and women, aged 71 years and over, who were evaluated in 1987-1989 and followed for a mean of 4.0 years. Outcome events were based on death certificates and Medicare hospitalization records. Analyses were adjusted for major CHD risk factors. There were 275 CHD deaths (16.8/1000 person-years) among all participants and 503 incident (fatal and nonfatal) CHD events (39.4 per 1000 person-years) among participants free of prevalent CHD during the observation period. The relative risk (RR) of CHD morality for women with an albumin concentration < 38 g/liter was 2.5 times higher than for women with albumin > 43 g/liter (RR 2.5; 95% confidence interval [CI], 1.4-4.6). There was a significant and graded increase in CHD incidence with decreasing albumin concentration in women but not in men. The presence of physical disability doubled the risk of CHD mortality among both men and women, an increase in risk that was comparable to that imposed by a previous myocardial infarction and was independent of other coronary risk factors. Disability had a lesser impact on CHD incidence, which was significant only in women. Low albumin concentration (< 38 g/liter) identifies a group of women at higher risk of CHD mortality and incidence. Physical disability is an independent predictor of CHD mortality in both men and women and for CHD incidence only in women.

Coronary heart disease risk factors in older persons

In most Western nations, coronary heart disease (CHD) is the leading cause of death and one of the most important causes of physical disability in persons over 65 years of age. The importance of traditional CHD risk factors has been well documented in middle-aged populations, whereas their role in older populations is still under debate. This paper reviews the epidemiologic evidence from observational studies and randomized clinical trials that established risk factors for CHD predict level of risk of CHD, and identify high risk individuals among older men and women. Hypertension and cigarette smoking have been clearly associated with an increased risk of CHD events, and their modification has been proven to be highly effective in the primary and secondary prevention of CHD in older persons. For other highly prevalent risk factors, such as lipid abnormalities, obesity and physical inactivity, evidence of an independent association with CHD risk has been demonstrated by the majority of observational studies. However, definitive proof from controlled clinical trials of the beneficial effects of their modification is still lacking in the older population. The role of estrogen replacement therapy in the primary and secondary prevention of CHD in old women is still an open question. In evaluating the impact of these risk factors in older persons, elements such as comorbidity, frailty, and age-related changes in risk profile should also be taken into consideration. Given the complexity of the relationship between risk factors and multiple disease statuses, other important outcomes, such as osteoporosis, cancer, falls and physical disability, should be considered when evaluating the risks and benefits of risk factor modifications in older persons.

Triglycerides and HDL-cholesterol as risk factors for ischemic heart disease. Results from the Québec cardiovascular study

The relative importance of reduced plasma high density lipoprotein-cholesterol (HDL-C) levels and elevated plasma triglyceride (TG) concentrations as risk factors for ischemic heart disease (IHD) was examined in a sample of 2177 men from the Québec City suburbs. The sample included 202 men with known IHD. The relationship between HDL-C and TG levels, although significant (r = -0.49, P < 0.0001), was not linear, as most of the variation in HDL-C levels was observed within TG levels below 2.5 mmol/l. Reduced HDL-C (< 0.9 mmol/l) was a prevalent condition in men with IHD (50%) compared to those without IHD (30%). On the other hand 26% and 20% of men with and without IHD, respectively, had elevated TG levels (TG > 2.3 mmol/l). A 2-fold increase in prevalence odds ratio (OR) was observed in men with TG levels > 2.3 mmol/l (95% confidence intervals (CI) [1.2;3.3]). No residual association between elevated TG levels and IHD was found, however, after adjustment for HDL-C concentrations (OR 1.2, 95% CI 0.7;2.1). On the other hand, HDL-C remained a significant predictor of IHD after adjustment for other risk factors (OR 0.3, 95%, CI 0.2;0.6). Men with reduced HDL-C levels were also characterized by a cluster of risk factors such as obesity, diabetes mellitus and hypertension, which may contribute to increase the risk of IHD. Finally, the independent interpretation of cholesterol, TG or LDL-C levels may lead to an inadequate prediction of risk, as a large number of IHD patients showed a cluster of risk factors which included low HDL-C concentrations.

Fibrinogen and silent atherosclerosis in subjects with cardiovascular risk factors

Fibrinogen may play an active role in the development and progression of atherosclerotic plaques. We assessed the association between fibrinogen levels and atherosclerotic plaques over three different arterial sites in an asymptomatic never-treated male population with increased cardiovascular risk. We included 652 men aged 40 to 60 years old with at least one of the following cardiovascular risk factors: cholesterol > 6.2 mmol/L and/or systolic blood pressure > or = 160 mm Hg and/or diastolic blood pressure > or = 95 mm Hg, and/or because they smoked. Carotid and femoral arteries and the abdominal aorta were assessed by using ultrasonographic methods for the presence of plaque, and subjects were categorized according to the presence (or absence) and extent (one versus two or three sites) of plaque. Plasma fibrinogen was measured according to the thrombin-time method of Clauss. While the presence of atherosclerosis was significantly related to age, current smoking, systolic pressure, LDL cholesterol, and fibrinogen levels, the extent of atherosclerosis was related to age and triglyceride and fibrinogen levels. Multiple regression analysis indicated independent associations between fibrinogen and the presence and extent of atherosclerosis. Plaque prevalence was significantly more pronounced with increasing tertile of fibrinogen levels. The odds ratio of the upper to lower fibrinogen tertiles for the presence of plaque was 1.6 (95% confidence interval, 1.4 to 1.8) and 1.4 (95% confidence interval, 1.2 to 1.7) for its extent. Adjustment for other risk factors slightly reduced the association between fibrinogen and atherosclerosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical factors and angiographic features associated with premature coronary artery disease

BACKGROUND

Clinical, angiographic, and biochemical features may differ in young patients with coronary heart disease compared with older patients.

METHODS

We compared clinical and angiographic characteristics in 100 male patients with clinical onset of disease at age < or = 45 years (group 1) with those of 100 older male patients (clinical onset of disease at > or = 60 years) (group 2). All patients had documented coronary artery disease. The two patient groups were compared in terms of the pattern of angina at disease onset, angiographic features, and coronary risk factors.

RESULTS

Seventy-six patients in group 1 and 49 patients in group 2 presented with acute coronary syndromes (unstable angina or myocardial infarction) at clinical disease onset (p < 0.001). Compared with patients in group 2, younger patients (group 1) showed a preponderance of single-vessel disease (54 vs 36%; p < 0.001) and complex stenosis morphologic features (59 vs 36%; p < 0.01). Family history of coronary artery disease (39 vs 11%; p < 0.001) and smoking (73 vs 46%; p < 0.001) were also more prevalent in younger patients. Mean plasma total cholesterol level was 6.4 +/- 1.3 mmol/L in group 1 and 6.1 +/- 1.2 mmol/L in group 2 (p = NS). Younger patients, however, had lower high-density lipoprotein (HDL) cholesterol (0.9 +/- 0.2 mmol/L and 1.1 +/- 0.4 mmol/L; p < 0.01) and higher plasma triglyceride levels compared with patients of group 2 (2.7 +/- 1.3 mmol/L vs 2.1 +/- 1.1 mmol/L; p < 0.001).

CONCLUSIONS

Patients with premature coronary disease referred to coronary angiography commonly have unheralded acute onset of symptoms, angiographically complex stenosis morphologic features, and less extensive coronary artery disease. In addition to previously identified risk factors such as family history and smoking, we observed that high plasma triglyceride and low HDL cholesterol levels are associated with premature coronary artery disease.

Smoking and mortality among residents of a California retirement community

Smoking cessation decreases mortality among the elderly. Participants in the Leisure World Cohort Study initiated in 1981 were followed until death or January 1, 1991. The 8869 women and 4999 men (median age = 73 years at initial survey) contributed 105,952 person-years of follow-up; 4002 had died. All-cause mortality rates were highest among current smokers; compared with never smokers the age-adjusted relative risks (and 95% confidence intervals) were 1.67 (1.46, 1.92) for women and 1.95 (1.66, 2.30) for men. Current smokers had increased risks of coronary heart disease, other cardiovascular disease, and cancer. Risk of death from smoking-related cancers continued to be high among former smokers, although lower than the risk among current smokers. Relative risks of mortality from cancer and cardiovascular disease increased with the number of cigarettes smoked per day and with a decreasing number of years since cessation of smoking.

Serum cholesterol and acute myocardial infarction: a case-control study from the GISSI-2 trial. Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto-Epidemiologia dei Fattori di Rischio dell'Infarto Miocardico Investigators

OBJECTIVE

To examine the role of serum cholesterol in acute myocardial infarction in a population of patients with no history of coronary heart disease and to establish the nature of this association, the degree of risk, and the possible interaction between serum cholesterol and other major risk factors for acute myocardial infarction.

DESIGN

Case-control study.

SETTING

90 hospitals in northern, central, and southern Italy.

PATIENTS

916 consecutive cases of newly diagnosed acute myocardial infarction and 1106 hospital controls admitted to hospital with acute conditions not related to known or suspected risk factors for coronary heart disease.

DATA COLLECTION

Data were collected with a structured questionnaire and blood samples were taken by venepuncture as soon as possible after admission to hospital from cases and controls. Blood cholesterol concentrations were available for 614 cases and 792 controls.

RESULTS

After adjustment by logistic regression for sex, age, education, geographical area, smoking status, body mass index, history of diabetes and hypertension, and family history of coronary heart disease the estimated relative risks of acute myocardial infarction for quintiles of serum cholesterol (from lowest to highest) were 2.3 (95% confidence interval (CI) 1.6 to 3.4), 3.1 (95% CI 2.1 to 4.6), 4.1 (95% CI 2.8 to 6.0), and 5.2 (95% CI 3.5 to 7.7). The estimated relative risk across selected covariates increased from the lowest to the highest quintile of serum cholesterol particularly for men, patients under 55 years of age, and smokers. When the possible interaction of known risk factors with serum cholesterol was examined, smoking habits, diabetes, and hypertension had approximately multiplicative effects on relative risk.

CONCLUSIONS

This study indicates that serum cholesterol was an independent risk factor for acute myocardial infarction. This association was linear, with no threshold level. Moreover, there was a multiplicative effect between cholesterol and other major risk factors on the relative risk of acute myocardial infarction.

Elevated serum cholesterol is a risk factor for both coronary heart disease and thromboembolic stroke in Hawaiian Japanese men. Implications of shared risk

BACKGROUND AND PURPOSE

The relation between total serum cholesterol level and thromboembolic or nonhemorrhagic stroke is controversial. The Honolulu Heart Program cohort of Japanese-American men provides data which show that elevated serum cholesterol is an independent predictor of thromboembolic stroke as well as coronary heart disease (CHD). The data are presented to suggest that the association of elevated cholesterol with stroke is sometimes underestimated or underreported partly because of competing or shared risk with CHD, the other major atherosclerotic end point.

METHODS

The data are based on 6352 men (aged 51 to 74 years) at baseline examination (1971 to 1974) who were free of clinical CHD and stroke and were followed an average of 15 years for new cases of both end points. Relative risks of serum cholesterol for CHD and thromboembolic stroke were calculated, controlling for other major cardiovascular covariates.

RESULTS

There was a continuous and progressive increase in both CHD and thromboembolic stroke rates with increasing levels of serum cholesterol. The relative risk between the highest and lowest quartiles of serum cholesterol was 1.7 (95% confidence interval, 1.4 to 2.0) for CHD and 1.4 (95% confidence interval, 1.1 to 1.9) for thromboembolic stroke. There was a decline in the difference in relative risks between CHD and thromboembolic stroke in older men (aged 60 years and older) compared with younger men (aged younger than 60 years).

CONCLUSIONS

These data provide additional evidence that elevated serum cholesterol should be considered a primary risk factor for thromboembolic stroke, presumably through its effect on both coronary and cerebrovascular atherosclerosis. It is suggested that this association is sometimes underestimated or underreported partly because of shared or competing risk with CHD, the clinical manifestation of atherosclerosis that generally occurs earlier in life and with greater frequency than thromboembolic stroke.

Serum triglycerides in the prediction of coronary artery disease (an Italian experience)

An occupational group living in Rome and composed of 3,007 men aged 46 to 65 years who were free from previous major coronary events was screened for a number of coronary risk factors and then followed up for 10 years. In all, 107 coronary deaths occurred in 10 years. There was a positive relation between coronary death rate and increasing levels of triglycerides, but the difference between the extreme quintile classes was not any more significant after adjustment for cholesterol levels. A cross-classification involving low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol and triglyceride levels showed a higher coronary artery disease (CAD) mortality in subjects with a higher LDL cholesterol/HDL cholesterol ratio and higher triglycerides. However, the excess risk in this subgroup was largely explained by the mean levels of total cholesterol. The multivariate proportional-hazards Cox model with coronary deaths as the end point, and age and triglycerides as predictors, produced a significant coefficient for triglycerides that became nonsignificant when other lipids alone or in combination (total, HDL and LDL cholesterol and some of their ratio) were fed into the model as further covariates. It is concluded that there is no evidence of an independent role of triglycerides in the prediction of coronary deaths.

Smoking and the incidence of coronary heart disease in an Australian population

OBJECTIVE

To estimate the impact of smoking on the incidence of coronary heart disease in Australia. Data collected for the WHO MONICA Project were used.

DESIGN

Combined data from a community-based register of all suspected coronary events and a survey of risk factor prevalence in a random sample of the same population.

SETTING AND PARTICIPANTS

All residents of the Hunter Region of New South Wales aged 35-69 years who had a first acute myocardial infarction or fatal heart attack (without a history of coronary heart disease) between 1 January 1986 and 31 December 1990.

MAIN OUTCOME MEASURES

Acute myocardial infarction or coronary death, as defined by the WHO MONICA Project.

RESULTS

Men who are current smokers are 2.9 times (95% CI, 2.7-3.1) more likely than non-smokers to have a first myocardial infarction or fatal heart attack, and for women the equivalent figure is 3.5 times (95% CI, 3.2-3.8), after adjusting for age. Current male smokers with a history of hypertension are 4.5 times more likely to have a coronary event (7.9 times in women) than are non-smokers without a history of hypertension. The age-adjusted excess rate was 566 per 100,000 per year in men and 373 per 100,000 per year in women. Smoking is a stronger predictor of coronary heart disease incidence than a history of hypertension (relative risk [RR] = 1.6 for men and 1.9 for women) or a known history of hypercholesterolaemia (RR not significantly different from 1).

CONCLUSIONS

Cigarette smoking plays a more important role in the causation of a first myocardial infarction or fatal heart attack and appears to have more influence on the incidence of coronary heart disease in Australia than hypertension.

Glucose tolerance and mortality from ischemic heart disease in an elderly population. Impact of repeated glucose measurements

The impact of glucose tolerance, measured repeatedly, on the mortality from ischemic heart disease (IHD) was assessed in a cohort of 202 elderly patients, aged 64 to 84 years in 1971, from a general practice. During the period from 1971 to 1975 the participants were examined annually. The area under the glucose tolerance curve (AUC) was used as a summary index, and for every subject the mean AUC over the 5-year period was calculated. This index was most strongly correlated with the mean 60-minute glucose level (r = 0.96). Between 1975 and 1987, 125 participants died, 28.8% of whom died from IHD. No association between a single measurement of glucose tolerance and IHD mortality was observed. However, using the mean AUC over the 5-year period, a positive association was observed, independent of age, sex, and other potential confounders (P = 0.04). These results indicate that glucose tolerance independently predicts mortality from coronary heart disease in an elderly cohort, provided that information on repeated measurements is taken into account. A continuous risk gradient is suggested.

Plasma triglyceride level and mortality from coronary heart disease

BACKGROUND

Whether the plasma triglyceride level is a risk factor for coronary heart disease has been controversial, and evaluation of the triglyceride level as a risk factor is fraught with methodologic difficulties.

METHODS

We studied the association between plasma triglyceride levels and the 12-year incidence of death from coronary heart disease in 10 North American populations participating in the Lipid Research Clinics Follow-up Study, while adjusting for the potential confounding effects of other risk factors for cardiovascular disease, including the level of high-density lipoprotein (HDL) cholesterol. All analyses were sex-specific, and separate analyses were performed in high and low strata of HDL cholesterol, low-density lipoprotein (LDL) cholesterol, fasting plasma glucose, and age.

RESULTS

The rates of coronary death in both men and women increased with the triglyceride level. In Cox proportional-hazards models adjusted for age, in which the natural log of the triglyceride levels was used to give a normal distribution, the relative risk per natural-log unit of triglyceride (e.g., a triglyceride level of 150 mg per deciliter vs. a level of 55 mg per deciliter) was 1.54 (95 percent confidence interval, 1.19 to 1.98; P < 0.001) in men and 1.88 (95 percent confidence interval, 1.19 to 2.98; P < 0.007) in women. After an adjustment for potential covariates, however, these relative risks were not statistically significant. Analyses based on lipoprotein cholesterol levels revealed a positive association between the triglyceride level and coronary mortality in the lower stratum of both HDL and LDL cholesterol, but not in the higher stratum. Conversely, the HDL cholesterol level was unrelated to coronary mortality in the lower stratum of LDL cholesterol, but was strongly inversely associated with coronary death in the higher stratum of LDL cholesterol. The relative risk of coronary death associated with triglyceride level was higher at younger ages. The associations between the triglyceride level and coronary mortality in the lower HDL cholesterol, LDL cholesterol, and age strata were small and were further reduced by an adjustment for the fasting plasma glucose level.

CONCLUSIONS

Overall, the plasma triglyceride level showed no independent association with coronary mortality. However, in subgroups of subjects with lower HDL and LDL cholesterol levels and in younger subjects, defined a priori, an association between the triglyceride level and coronary mortality was observed, although this association was small and was not statistically significant after an adjustment for the plasma glucose level.

The association of changes in physical-activity level and other lifestyle characteristics with mortality among men

BACKGROUND

Recent trends toward increasing physical exercise, stopping cigarette smoking, and avoiding obesity may increase longevity. We analyzed changes in the lifestyles of Harvard College alumni and the associations of these changes with mortality.

METHODS

Men who were 45 to 84 years of age in 1977 and who had reported no life-threatening disease on questionnaires completed in 1962 or 1966 and again in 1977 were classified according to changes in lifestyle characteristics between the first and second questionnaires. We analyzed changes in their level of physical activity, cigarette smoking, blood pressure, and body weight, and the relation of these factors to mortality between 1977 and 1985.

RESULTS

Of the 10,269 men, 476 died during this period (which totaled 90,650 man-years of observation). Beginning moderately vigorous sports activity (at an intensity of 4.5 or more metabolic equivalents) was associated with a 23 percent lower risk of death (95 percent confidence interval, 4 to 42 percent; P = 0.015) than not taking up moderately vigorous sports. Quitting cigarette smoking was associated with a 41 percent lower risk (95 percent confidence interval, 20 to 57 percent; P = 0.001) than continuing smoking, but with a 23 percent higher risk than constant nonsmoking. Men with recently diagnosed hypertension had a lower risk of death than those with long-term hypertension (relative risk, 0.75; 95 percent confidence interval, 0.55 to 1.02; P = 0.057), as did men with consistently normal blood pressure (relative risk, 0.52; 95 percent confidence interval, 0.40 to 0.68; P < 0.001). Maintenance of lean body mass was associated with a lower mortality rate than long-term, recent, or previous obesity. The associations between changes in lifestyle and mortality were independent and were largely undiminished by age. Our findings on death from coronary heart disease mirrored those on death from all causes.

CONCLUSIONS

Beginning moderately vigorous sports activity, quitting cigarette smoking, maintaining normal blood pressure, and avoiding obesity were separately associated with lower rates of death from all causes and from coronary heart disease among middle-aged and older men.

Metabolic heterogeneity associated with high plasma triglyceride or low HDL cholesterol levels in men

To further understand the factors involved in the regulation of high plasma triglyceride (TG) or low plasma high density lipoprotein cholesterol (HDL-C) levels, three groups of male subjects (normal TG with low HDL-C levels, high TG with normal HDL-C levels, and high TG with low HDL-C levels) were compared with a sample of normolipemic men with normal TG and HDL-C plasma levels. Mean age was 34 years (range, 20-42 years), and none of the subjects had plasma TG levels > 4.0 mmol/l or familial hypercholesterolemia. Both groups of subjects with high TG levels had a higher body mass index, waist circumference, waist-to-hip circumferences ratio, and a higher ratio of abdominal to femoral adipose tissue areas as measured by computed tomography when compared with normolipemic control subjects. However, during an oral glucose tolerance test only high TG-low HDL-C men had fasting hyperinsulinemia and higher plasma insulin levels compared with normolipemic subjects. In addition, the high TG-low HDL-C group showed reduced HDL apoprotein (apo) A-I levels and a low HDL2-C/HDL3-C ratio. These changes were observed along with a nonsignificant trend for a lower plasma postheparin lipoprotein lipase activity. However, among subjects with high TG and normal HDL-C levels, no evidence of insulin resistance or of a reduction in postheparin lipoprotein lipase activity was observed, suggesting that the high plasma TG levels could be attributed to an increased production of apo B-containing lipoproteins, as high plasma apo B and low density lipoprotein (LDL)-apo B levels were observed in this group.(ABSTRACT TRUNCATED AT 250 WORDS)

The importance of triglycerides: results from the Prospective Cardiovascular Münster (PROCAM) Study

In the PROCAM study hypertriglyceridaemia was much more common among men (18.6%) than women (4.2%). Prevalence increased with age in women, but remained nearly constant at about 20% in men aged 35 years or more. In a multiple regression analysis a strong negative correlation between triglycerides and HDL cholesterol was found. A positive relationship was observed with cholesterol, blood glucose, factor VIIc, and PAI-1 in both sexes. Only in men, triglycerides are positively correlated with Apo A-I, body mass index, cigarette smoking, and alcohol consumption. Postmenopausal women showed higher triglyceride levels than premenopausal women. No independent relationships were observed to age, blood pressure, Lp(a), Apo A-II, Apo B, AT-III, protein C, fibrinogen, and oral contraceptives. A longitudinal analysis of data from 4474 male PROCAM participants aged 40-64 years with a follow-up of 4 years did not identify triglycerides as an independent risk factor, but the data suggest hypertriglyceridaemia is an additional risk factor for CHD, when excessive triglycerides coincide with a high ratio of plasma cholesterol to HDL-cholesterol and with low HDL-cholesterol values.

Coronary calcification and its relation to extracoronary atherosclerosis in asymptomatic hypercholesterolemic men. The PCV METRA Group

BACKGROUND

The prevalence of coronary calcifications and extracoronary plaques was studied in patients with asymptomatic hypercholesterolemia.

METHODS AND RESULTS

Ultrafast computed tomography for coronary calcification (presence or absence: calcium score) and echographic assessment of carotid, aortic, and femoral plaques were performed in 111 hypercholesterolemic men: 65% had coronary calcification, 72% had extracoronary plaque. The two lesions were associated as: 1) compared with subjects without coronary calcification, those with calcification had a higher prevalence of aortic (p less than 0.05) and femoral (p less than 0.01) plaque and of two diseased sites (p less than 0.05); 2) the prevalence of coronary calcification was higher in the presence than in the absence of aortic (p less than 0.05) or femoral (p less than 0.01) plaque and higher in two (p less than 0.01) and three diseased (p less than 0.05) sites than in no diseased site; 3) the calcium score was higher in the presence than in the absence of carotid (p less than 0.05), aortic (p less than 0.05), or femoral (p less than 0.001) plaque, higher in two (p less than 0.001) and three diseased (p less than 0.05) sites than in no diseased sites, and higher in two (p less than 0.01) than in one diseased site; and 4) the calcium score correlated with femoral plaque (p less than 0.001). Overall, the presence of two or three diseased extracoronary sites versus no or one diseased site showed a power of 78% for predicting coronary calcification. Coronary calcium score correlated with age (p less than 0.01) and triglycerides (p less than 0.05).

CONCLUSIONS

The close relation between coronary calcium and extracoronary plaques suggests that echography of extracoronary vessels could aid in the screening of coronary atherosclerosis in high-risk, asymptomatic individuals.

Will lowering population levels of serum cholesterol affect total mortality? Expectations from the Honolulu Heart Program

Major campaigns now underway to reduce the serum cholesterol levels of entire national populations have not given serious consideration to the high rates of noncardiovascular disease and death associated with low cholesterol levels (less than 190 mg/dl). To explore this problem, the relationships between serum cholesterol levels, measured in 1965-1968 in 7478 Japanese American men in Hawaii, and subsequent total and cause-specific mortality through 1985, were analyzed by multivariate Cox regression to control for potential confounders. Total mortality rates for 1648 deaths showed a U-shaped curve by baseline cholesterol level, with significant inverse trends (p less than 0.03) for deaths due to hemorrhagic stroke, all cancer, benign liver disease, chronic obstructive lung disease and "unknown cause". Only the inverse trends for cancer and benign liver disease showed flattening when 227 deaths in the first 5 years of follow-up were deleted from the analysis. Simulation models using three different strategies of cholesterol reduction in this cohort revealed that none of these approaches had any substantial impact on predicted total mortality over 15 years. However, the population-based approach might theoretically increase mortality for 60% of the cohort with baseline cholesterol levels less than 225 mg/dl.

Smoking and mortality among older men and women in three communities

BACKGROUND

Although cigarette smoking is the leading avoidable cause of premature death in middle age, some have claimed that no association is present among older persons.

METHODS

We prospectively examined the relation of cigarette-smoking habits with mortality from all causes, cardiovascular causes, and cancer among 7178 persons 65 years of age or older without a history of myocardial infarction, stroke, or cancer who lived in one of three communities: East Boston, Massachusetts; Iowa and Washington counties, Iowa; and New Haven, Connecticut. At the time of the initial interview, prevalence rates of smoking in the three communities ranged from 5.2 to 17.8 percent among women and from 14.2 to 25.8 percent among men. During five years of follow-up there were 1442 deaths, 729 due to cardiovascular disease and 316 due to cancer.

RESULTS

In both sexes, rates of total mortality among current smokers were twice what they were among participants who had never smoked. Relative risks, as adjusted for age and community, were 2.1 among the men (95 percent confidence interval, 1.7 to 2.7) and 1.8 among the women (95 percent confidence interval, 1.4 to 2.4). Current smokers had higher rates of cardiovascular mortality than those who had never smoked (as adjusted for age and community, the relative risk was 2.0 [95 percent confidence interval, 1.4 to 2.9] among the men and 1.6 [95 percent confidence interval, 1.1 to 2.3] among the women), as well as increased rates of cancer mortality (relative risk, 2.4 [95 percent confidence interval, 1.4 to 4.1] among the men and 2.4 [95 percent confidence interval, 1.4 to 3.9] among the women). In both sexes, former smokers had rates of cardiovascular mortality similar to those of the participants who had never smoked, regardless of age at cessation, whereas the rates for all cancers, as well as smoking-related cancers, remained elevated among men who had once smoked.

CONCLUSIONS

Our prospective findings indicate that the mortality hazards of smoking extend well into later life, and suggest that cessation will continue to improve life expectancy in older people.

Self-report of physical activity and patterns of mortality in Seventh-Day Adventist men

The Adventist Mortality Study provides 26-year follow-up through 1985 for 9484 males who completed a lifestyle questionnaire in 1960. The relationship of self-reported physical activity and all cause and disease-specific mortality was examined by survival analysis and with the Cox proportional hazards model, controlling for demographic and lifestyle characteristics. Moderate activity was associated with a protective effect on cardiovascular and all cause mortality in both analyses. In the Cox model, age-specific estimates of relative risk (RR) were obtained for several endpoints due to a significant interaction between level of physical activity and attained age (age at death or end of follow-up). This model permits calculation of the age at which the RR = 1.0, or the age at crossover of risk. For moderate activity, this age was 95.6 years (95% confidence intervals, 81.7-109.4 years) for all cause mortality and 91.5 years (95% confidence intervals, 79.0-104.0 years) for cardiovascular mortality. While the protective effect on mortality associated with moderate activity decreased with increasing age, it remained significant to the verge of the present life span.

Plasma triglyceride and coronary heart disease

Although the literature on epidemiological associations between plasma triglyceride and CHD is not completely consistent, trends do emerge from the studies described here. First, the majority of observational studies demonstrate a significant univariate relation, although the results of case-control and cross-sectional studies are more uniform than those from prospective study designs. In many but not all studies, triglyceride remains a significant predictor of CHD in multivariate statistical analyses after controlling for TC or LDL-C. Perhaps the least consistent result is that the triglyceride association does not persist in some analyses controlling for HDL-C, while in other studies, the association remains significant. Although most studies have been conducted in men, the studies providing data on women, normocholesterolemic subjects, and diabetic subjects have generally found triglyceride to be, at the very least, a univariate risk factor. The results of intervention trials differ considerably, but no such study to date has been specifically designed to evaluate triglyceride-lowering effects on primary prevention of CHD. Important statistical properties must be taken into consideration in evaluating triglyceride as a risk factor for CHD. The large variability of triglyceride measurements and the correlation of triglyceride values with other lipid measures appears to result in the underestimation of the association between triglyceride and disease in multivariate analyses. Finally, individual genetic susceptibility may play an important role in the relation between plasma triglyceride levels and CHD. For example, risk of CHD clearly varies among the well-established familial forms of hypertriglyceridemia. A predominance of small, dense, LDL particles (LDL subclass pattern B) also appears to be a genetic trait associated with both increased risk of MI and increases in plasma triglyceride levels.