Influence of high-density lipoprotein cholesterol and rheological factors on the sex difference in cardiovascular disease.

BACKGROUND: It is well established that the incidence of cardiovascular disease among men is higher than that among women. OBJECTIVE: To determine whether differences between men and women in terms of a range of conventional and rheological risk factors could explain this sex difference. DESIGN: This was a population-based cohort study (the Edinburgh Artery Study). METHODS: Men and women aged 55-74 years (n = 1592) were selected at random from the general population of Edinburgh and followed up for 5 years. Baseline cardiovascular risk factors were measured and related to incidence of disease among men and women. RESULTS: Men had higher levels of cigarette smoking, haematocrit and blood viscosity and lower levels of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol and plasma fibrinogen than did women. The incidences of cardiovascular events among men and women were 48.3 and 26.1 per 1000 person-years, respectively. Adjustment for level of HDL cholesterol reduced the male:female ratio for sex-specific incidence rates of cardiovascular events from 1.80 [95% confidence interval (CI) 1.43-2.27] to 1.34 (95% CI 1.04-1.73). This reduction was partially reversed after further adjustment for the other cardiovascular risk factors. The impact of blood viscosity, plasma viscosity and plasma level of fibrinogen on the risk of cardiovascular disease was higher for men than it was for women (multivariate relative risk for blood viscosity were 1.24, 95% CI 1.08-1.43, for men and 0.81, 95% CI 0.61-1.06, for women). CONCLUSIONS: Levels of HDL cholesterol levels in women being higher than those in men may explain some, but not all, of the sex difference in incidence of cardiovascular disease. Greater susceptibility of men to rheological factors might also be important.

Is intermittent claudication improved by percutaneous transluminal angioplasty? A randomized controlled trial.

PURPOSE: Percutaneous transluminal angioplasty (PTA) is an increasingly popular invasive treatment for peripheral arterial disease, but there have been very few controlled trials to justify its use. This randomized controlled clinical trial was performed to determine in patients with mild and moderate intermittent claudication differences in outcome between PTA and conventional medical treatment after 2 years. METHODS: Six hundred patients with claudication were screened at the Peripheral Vascular Clinic, Royal Infirmary of Edinburgh. Sixty-two patients with short femoral artery stenoses or occlusions (47 patients) and iliac stenoses (15 patients) were randomized to either PTA plus medical treatment (PTA group, 30 patients) or to medical treatment alone (control group, 32 patients). Medical treatment consisted of daily low-dose aspirin and advice on smoking and exercise. Outcome measures studied were patient-reported maximum walking distance, exercise treadmill distance until onset of claudication, treadmill maximum walking distance, ankle-brachial pressure index (ABPI), quality of life (Nottingham Health Profile), and duplex ultrasound-measured extent of occlusive disease. RESULTS: At 2 years of follow-up, the PTA group and control subjects did not differ significantly in patient-reported maximum walking, treadmill onset to claudication, treadmill maximum walking distances, or ABPI (p > 0.05). However, the PTA group had significantly fewer occluded arteries (p = 0.003) and a lesser degree of stenosis (expressed in terms of the velocity ratio; p = 0.004) in patent arteries. Quality of life was not demonstrably different between the two groups (p > 0.05). CONCLUSIONS: Two years after PTA, patients had less extensive disease than medically treated patients, but this did not translate into a significant advantage in terms of improved walking or quality of life. There are important implications for patient management and future clinical research.

Use of ankle brachial pressure index to predict cardiovascular events and death: a cohort study.

OBJECTIVE: To determine whether a low ankle brachial pressure index is associated with an increased risk of cardiovascular events and death, and whether the prediction of such events could be improved by including this index. DESIGN: Cohort study. SETTING: 11 practices in Edinburgh, Scotland. SUBJECTS: 1592 men and women aged 55-74 years selected at random from the age-sex registers of 11 general practices and followed up for 5 years. MAIN OUTCOME MEASURES: Incidence of fatal and non-fatal cardiovascular events and all cause mortality. RESULTS: At baseline 90 (5.7%) of subjects had an ankle brachial pressure index < or = 0.7, 288 (18.2%) had an index < or = 0.9, and 566 (35.6%) < or = 1.0. After five years subjects with an index < or = 0.9 at baseline had an increased risk of non-fatal myocardial infarction (relative risk 1.38, 95% confidence interval 0.88 to 2.16), stroke (1.98, 1.05 to 3.77), cardiovascular death (1.85, 1.15 to 2.97), and all cause mortality (1.58, 1.14 to 2.18) after adjustment for age, sex, coronary disease, and diabetes at baseline. The ability to predict subsequent events was greatly increased by combining the index with other risk factors--for example, hypertensive smokers with normal cholesterol concentrations had a positive predictive value of 25.0%, increasing to 43.8% in subjects with a low index and decreasing to 15.6% in those with a normal index. CONCLUSION: The ankle brachial pressure index is a good predictor of subsequent cardiovascular events, and improves on predictions by conventional risk factors alone. It is simple and accurate and could be included in routine screening of cardiovascular status.

Incidence, natural history and cardiovascular events in symptomatic and asymptomatic peripheral arterial disease in the general population.

BACKGROUND: Intermittent claudication is associated with a poor prognosis, but less is known of the risks associated with asymptomatic peripheral arterial disease. The aims of this study were to determine the incidence and natural history of claudication, and the incidence of cardiovascular events in symptomatic and asymptomatic peripheral arterial disease. METHODS: In 1988, 1592 subjects aged 55-74 years were selected randomly from the age-sex register of 10 general practices in Edinburgh, Scotland. The presence of peripheral arterial disease was determined by the World Health Organization questionnaire on intermittent claudication, the ankle brachial pressure index and a reactive hyperaemia test. This cohort was followed prospectively over 5 years for subsequent cardiovascular events and death. RESULTS: One hundred and sixteen new cases of claudication were identified (incidence density 15.5 per 1000 person-years). Of those with claudication at baseline, 28.8% and still had pain after 5 years, 8.2% underwent vascular surgery or amputation, and 1.4% developed leg ulceration. Claudicants had a significantly increased risk of developing angina compared with normals (RR: 2.31, 95% CI: 1.04-5.10), and asymptomatic subjects had a slightly increased risk of myocardial infarction and stroke. Deaths from cardiovascular disease were more likely in both claudicants (RR: 2.67, 95% CI: 1.34-5.29) and subjects with major (RR: 2.08, 95% CI: 1.13-3.83) or minor asymptomatic disease (RR: 1.74, 95% CI: 1.09-2.76). Subjects with major asymptomatic disease also had an increased risk of non-cardiovascular death (RR: 2.19, 95% CI: 1.33-3.59), and therefore had the highest overall risk of death (RR: 2.44, 95% CI: 1.59-3.74). CONCLUSIONS: Subjects with asymptomatic peripheral arterial disease appear to have the same increased risk of cardiovascular events and death found in claudicants.

Randomised controlled trial of percutaneous transluminal angioplasty for intermittent claudication.

OBJECTIVES: To determine differences between PTA and conventional medical treatment in treadmill distance until onset of claudication, treadmill maximum walking distance, patient reported maximum walking distance, ankle brachial pressure index (ABPI), quality of life (Nottingham Health Profile, NHP) and Duplex measured extent of occlusive disease. DESIGN: Randomised controlled clinical trial. METHODS: Six hundred claudicants were screened. Fifty-one men and 11 women with intermittent claudication due to short femoral stenoses or occlusions (n = 47) and iliac stenoses (n = 15) were randomised to either PTA plus medical treatment (PTA group, n = 30) or to medical treatment alone (control group, n = 32). Medical treatment consisted of daily low dose aspirin and advice on smoking and exercise. RESULTS: At 6 month follow up: In the PTA group more patients reported no claudication (p < or = 0.05) and were asymptomatic on the treadmill (p < or = 0.01) compared to the control group. The ABPI was significantly higher in the PTA group. More of the PTA group reported lower NHP pain scores (p < or = 0.05). In the control group there were more occluded arteries (p < or = 0.001), and the stenosis velocity ratio of patient arteries was significantly higher (p < or = 0.001). CONCLUSIONS: Only 10% of claudicants had discrete lesions suitable for PTA. Treatment of these patients with PTA produces a greater short-term improvement in walking and quality of life than medical treatment alone and is associated with less progression of disease.

Inter-relationships of plasma fibrinogen, low-density lipoprotein cholesterol, cigarette smoking and the prevalence of cardiovascular disease.

BACKGROUND: The magnitude of the cardiovascular risk associated with plasma fibrinogen concentration is influenced separately by cigarette smoking and by low-density lipoprotein (LDL) cholesterol levels. The effects of combinations of these factors on risk and the extent to which inclusion of the plasma fibrinogen level further refines the risks associated with smoking and high LDL cholesterol levels are not known. OBJECTIVE: To determine the inter-relationships among all of the three factors smoking, LDL cholesterol level and fibrinogen level with respect to the occurrence of cardiovascular disease. METHODS: The study was part of the Edinburgh Artery Study, which was a cross-sectional random sample survey of 1592 men and women aged 55-74 years. The assessment of cardiovascular disease included recall of diagnosis by a doctor of angina or myocardial infarction, intermittent claudication determined by a questionnaire and measurement of ankle systolic blood pressure. RESULTS: The odds ratio for disease in smokers in the top tertiles of plasma fibrinogen and LDL cholesterol levels was 7.7 (95% confidence interval 3.0-19.8; P < or = 0.001). Neither a multiplicative nor a synergistic effect of the three factors on the odds of disease was observed but the level of each contributed to the risk. For example, in current smokers in the bottom tertile of LDL cholesterol level, the odds of disease were 6.1 (95% confidence interval 2.2-17.0; P < or = 0.001) in the top tertile, 2.9 (95% confidence interval 1.0-8.6; P < or = 0.05) in the middle tertile and 1.6 (95% confidence interval 0.5-4.8; P > 0.05) in the bottom tertile of plasma fibrinogen level. Subjects in the bottom tertile of plasma fibrinogen level did not have significantly elevated (P < 0.05) risks irrespective of LDL cholesterol levels and smoking status. CONCLUSION: The incorporation of plasma fibrinogen level permitted more precise delineation of the odds of disease within categories of smoking and LDL cholesterol concentration. These relationships need to be investigated further in prospective studies.

The relationship between cigarette smoking and cardiovascular risk factors in peripheral arterial disease compared with ischaemic heart disease. The Edinburgh Artery Study.

Cigarette smoking is probably the most important risk factor for the development of peripheral arterial disease, but it may be less important in the aetiology of ischaemic heart disease. The objectives of this study were to determine whether any other cardiovascular risk factors showed a significant interaction with cigarette smoking which would explain the greater association between smoking and peripheral atherosclerosis. One thousand five hundred and ninety-two subjects aged 55-74 years were selected randomly from the age-sex registers of 10 general practices in Edinburgh, Scotland. The presence of peripheral arterial disease was determined by the World Health Organisation questionnaire on intermittent claudication, the ankle brachial pressure index and a reactive hyperaemia test. Heart disease was identified by the patients' recall of a doctor diagnosis of angina or myocardial infarction. There were 131 subjects with peripheral arterial disease but no ischaemic heart disease, and 169 with heart disease without peripheral disease. Significantly more smokers occurred in the peripheral than the heart disease group (P <0.01), and in current smokers the age and sex adjusted odds ratio were highly significant for peripheral arterial disease (odds ratio 5.09, 95% confidence interval 2.97-8.72, P<0.001), but not for heart disease (odds ratio 1.72, 95% confidence interval 0.98-2.33, P>0.05). Subjects with lower limb disease also had higher systolic pressures (P<0.001), serum high density lipoprotein cholesterol (P<0.01) and plasma fibrinogen (P<0.05). On logistic regression, adjusting for a range of individual risk factors had no significant impact on the effect of smoking. Plasma fibrinogen produced the biggest reduction in odds ratio (4.23, 95% confidence interval 2.44-7.35, in current smokers with peripheral arterial disease). Therefore the stronger association between smoking and peripheral arterial disease than ischaemic heart disease does not appear to be influenced by the other risk factors examined here, and must be explained by some other mechanism.

Alcohol intake as a risk factor for peripheral arterial disease in the general population in the Edinburgh Artery Study.

The aim of this study was to determine the relationship between alcohol consumption and occurrence of peripheral arterial disease in the general population. During 1988 in a cross sectional survey, the Edinburgh Artery Study, 1,592 men and women aged 55-74 years were selected at random from the age-sex registers of ten general practices distributed geographically and socio-economically across the city. participants were asked to recall the number of units of wine, beer and spirits consumed in the previous week and whether or not this was typical. Peripheral arterial disease was measured using the ankle brachial pressure index (ABPI). Men and women were analysed separately because of large differences in alcohol consumption. There was no association between ABPI and alcohol consumption in women but, in men, increasing alcohol consumption was associated with a higher ABPI (test for trend, p = 0.03) indicating less severe disease. This relationship was linear rather than U-shaped. In multiple regression analysis, after age-adjustment the ABPI was related to wine consumption but not beer or spirits in men (p < or = 0.01). On adjusting for age and cumulative lifetime cigarette smoking, the association of wine consumption with the ABPI was diminished but remained statistically significant (p < 0.05). On adjusting for age and social class, the relationship of total alcohol intake and wine consumption with the ABPI became non significant (p > 0.05). We conclude that in males, greater alcohol consumption is related to a higher ABPI and that any protective 'effect' of alcohol relates to wine consumption rather than beer or spirits.(ABSTRACT TRUNCATED AT 250 WORDS)

Sex differences in susceptibility to etiologic factors for peripheral atherosclerosis. Importance of plasma fibrinogen and blood viscosity.

Cardiovascular risk factors in men, such as cigarette smoking, hypercholesterolemia, and hypertension, also increase risk in women, but the relative susceptibility to risk factors between the sexes is not established. Our aim was to investigate a wide range of possible etiologic factors in a single population study and identify those that were more strongly related to peripheral atherosclerosis in men or women. We studied personal factors (age and social class), lifestyle factors (smoking, exercise, alcohol intake, and dietary nutrients), and intermediary factors (obesity, diabetes, serum lipids, coagulation, and rheological factors). In the Edinburgh Artery Study in 1988 we measured cardiovascular risk factors in a random population sample of 1592 men and women aged 55 to 74 years. The ankle-brachial pressure index (ABPI), which is inversely related to the degree of peripheral atherosclerosis, was assessed in each subject. Lifetime cigarette smoking was correlated with a lower ABPI equally in men and women (r = -.27, P < .001). Dietary nutrients and alcohol intake were not related differently between the sexes with ABPI. However, recall of strenuous and moderate leisure time exercise during the age range of 35 to 45 years was related more strongly to a higher ABPI in men than in women (P < .05). Plasma fibrinogen, plasma viscosity, and blood viscosity were the only intermediary factors that had stronger univariate correlations with lower ABPI in men than in women. On multivariate analysis, the sex differences persisted for plasma fibrinogen (P < .05) and blood viscosity (P < .001); high-density lipoprotein cholesterol was related to ABPI in men only (sex difference, P < .1).(ABSTRACT TRUNCATED AT 250 WORDS)

Hostile personality and risks of peripheral arterial disease in the general population.

The relationships between personality and risks of coronary heart disease have been studied widely, but little attention has been paid to other forms of atherosclerotic disease. The objective of this study was to determine relationships in the general population between hostile personality and Type A behavior pattern with asymptomatic and symptomatic chronic peripheral arterial disease. The Edinburgh Artery Study comprises a cross-sectional random sample survey of 1592 men and women aged 55 to 74 years sampled from age-sex registers of 10 general practices throughout the city. Peripheral arterial disease was measured using the WHO questionnaire on intermittent claudication, the ankle brachial pressure index, and a reactive hyperemia test. The Bedford Foulds personality deviance questionnaire was used to elicit extrapunitiveness, intropunitiveness, and dominance (including hostile acts); and the Bortner self-administered questionnaire was used to determine Type A/B personality. Hostile acts increased with severity of peripheral arterial disease; there was a mean score of 13.9 in normals and 14.6 in claudicants (p < .05). An increased risk of claudication associated with a one SD increase in hostile acts was significant (p < .05) only in males, odds ratio, 1.41 (95% confidence interval 1.01, 1.96) and was independent of cigarette smoking, alcohol consumption, obesity, and diabetes mellitus. Dominance was also related to asymptomatic peripheral arterial disease in subjects who had neither intermittent claudication nor angina. Contrary to expectations, Type A personality behaviour scores decreased with the severity of peripheral arterial disease. We conclude that hostile personality may be an independent risk factor for chronic peripheral arterial disease in the general population, particularly among men.

Physical activity and risk of peripheral arterial disease in the general population: Edinburgh Artery Study.

STUDY OBJECTIVE: To determine associations between physical activity at age 35-45 years with peripheral arterial disease and cardiovascular risk factors at age 55-74 years. DESIGN: Cross sectional survey of the general population--Edinburgh Artery Study. The presence of peripheral arterial disease was determined using the WHO/Rose questionnaire on intermittent claudication, and the ankle brachial pressure index at rest and during reactive hyperaemia. Levels of physical activity undertaken at the time of the survey and at the times the subjects were aged 35-45 years were measured by self administered recall questionnaire. SETTING: City of Edinburgh, Scotland. PARTICIPANTS: Altogether 1592 men and women aged 55 to 74 years, selected from the age-sex registers of 10 general practices spread geographically and socioeconomically throughout the city. MAIN RESULTS: Participation in moderate or strenuous activity when aged 35-45 years was reported by 66% of men and 40% of women. In men, but not in women, less peripheral arterial disease (measured by an increasing trend in the ankle brachial pressure index) was found with increasing amounts of exercise at age 35-45 years (p < 0.001). Higher levels of exercise at age 35-45 years were associated with lower blood viscosity (p < 0.05) and plasma fibrinogen levels (p < 0.05) in men and women aged 55-74 years, and also with higher current alcohol intake (p < 0.001) and high density lipoprotein cholesterol concentrations (p < 0.01) in women aged 55-74 years. After adjustment for age, sex, life-time smoking, social class, body mass index, and alcohol intake, the association between leisure activity aged 35-45 years and the ankle brachial pressure index aged 55-74 years remained highly significant in men who had at some time smoked (p < 0.001) but not in men or women who had never smoked (p > 0.05). CONCLUSION: The risk of peripheral arterial disease, particularly among male smokers, is inversely related to previous physical activity in early middle age, suggesting a protective effect of exercise.

Smoking, haemostatic factors and lipid peroxides in a population case control study of peripheral arterial disease.

The aim of this study was to determine differences between cases of peripheral arterial disease and healthy controls in levels of haemostatic factors and lipid peroxides and the influence of cigarette smoking. The study groups were selected from the Edinburgh Artery Study which is a random sample survey of men and women aged 55-74 years. Mean levels of plasma fibrinogen, von Willebrand factor, beta-thromboglobulin, plasminogen activator inhibitor (type I), cross-linked fibrin degradation products and lipid peroxides were markedly elevated in 121 study cases compared with 126 age- and sex-matched controls. For example, cross-linked fibrin degradation products had a geometric mean of 106.8 ng/ml (95% confidence interval (CI) 95.3, 119.8) in study cases and 74.7 ng/ml (95% CI 67.0, 83.4) in controls (P < 0.001). Inclusion of smoking in logistic regressions of each factor on peripheral arterial disease significantly reduced the odds of disease for von Willebrand factor and for cross-linked fibrin degradation products, but had little effect on the increased odds associated with fibrinogen, beta-thromboglobulin, plasminogen activator inhibitor and lipid peroxides. We conclude that, in men and women in Edinburgh, peripheral atherosclerosis is associated with lipid peroxidation, endothelial disturbance, platelet activation, elevated fibrinogen, fibrin formation and increased inhibition of fibrinolysis. The most important effects of cigarette smoking in promoting atherosclerosis may be endothelial disturbance and fibrin formation.

Cross-linked fibrin degradation products, progression of peripheral arterial disease, and risk of coronary heart disease.

Haemostatic and rheological factors may predict cardiovascular disease. We studied patients with intermittent claudication to see if the progression of peripheral arterial disease and the risks of coronary events could be predicted by baseline packed cell volume, plasma fibrinogen, blood and plasma viscosites, von Willebrand factor antigen, cross-linked fibrin degradation products (XLFDP), urinary fibrinopeptide A, and plasma leucocyte elastase. In 617 patients with claudication followed up for one year, baseline XLFDP was related most strongly to coronary events, relative risk 4.4 (95% CI 1.3-19.0) between top and bottom quintiles. Plasma fibrinogen was the strongest independent predictor of death from coronary disease. XLFDP was the only factor, in addition to age and cigarette smoking, that was independently associated (p = 0.008) with deterioration in peripheral arterial disease. We conclude that, in patients with peripheral arterial disease, plasma concentration of XLFDP, a measure of ongoing fibrin formation and degradation, is a strong predictor of both disease progression and future coronary risk. These results accord with the hypothesis that fibrin formation contributes to progression of coronary and peripheral atherosclerosis.

Blood viscosity, fibrinogen, and activation of coagulation and leukocytes in peripheral arterial disease and the normal population in the Edinburgh Artery Study.

BACKGROUND: Increased blood and plasma viscosity, hematocrit, fibrinogen, and activation of coagulation and leukocytes have been reported in patients with claudication; however, their associations with symptomatic and asymptomatic peripheral arterial disease have not been reported in an epidemiological study. METHODS AND RESULTS: Blood and plasma viscosity, hematocrit, fibrinogen, urinary fibrinopeptide A, plasma leukocyte elastase, and uric acid were measured in a random sample of 1,581 men and women aged 55-74 years in Edinburgh, Scotland, and related to peripheral arterial stenosis (ankle-brachial systolic pressure index, ABPI) and to lower limb ischemia (intermittent claudication and reactive hyperemia test). Each variable (except fibrinopeptide A) was significantly related to prevalent symptomatic and asymptomatic peripheral arterial disease. On multivariate analysis, blood viscosity (p < 0.05) and fibrinogen (p < 0.01) were independently associated with peripheral arterial narrowing (ABPI); a positive interaction was found between fibrinogen and smoking in the association with ABPI. Plasma viscosity was associated with claudication in the presence of a given degree of arterial narrowing (odds ratio of claudication in top quintile compared with bottom quintile of plasma viscosity, 3.35; 95% CI, 1.32, 8.51). Leukocyte elastase and uric acid were each associated with reactive hyperemia independently of arterial narrowing (p < 0.01). CONCLUSIONS: Blood rheological factors and leukocyte activation as well as arterial narrowing are associated with lower limb ischemia in the general population and may be implicated in its pathogenesis.

Diet as a risk factor for peripheral arterial disease in the general population: the Edinburgh Artery Study.

The Edinburgh Artery Study included a cross-sectional survey of 1592 men and women (aged 55-74 y). One aim was to examine relationships between an indicator of peripheral arterial disease, the ankle brachial pressure index (ABPI), and dietary factors. Nutrient intake was derived from a food-frequency questionnaire. Higher frequency of consumption of fiber-containing foods was associated with greater mean ABPI in males and higher consumption of meat and meat products were significantly associated with low mean ABPI in males and females. In a multiple linear regression with ABPI as outcome and energy-adjusted nutrients as predictors, cereal fiber (P = 0.02) and alcohol (P = 0.04) were positively associated with the ABPI in males but not in females. Dietary vitamin E(alpha-tocopherol) intake was positively associated with ABPI (P = 0.04) independently of smoking and other nutrients. Dietary vitamin C intake was significantly related to ABPI (P = 0.006) only among those who had ever smoked.

Reactive hyperemia test in a random sample of the general population.

PURPOSE: The purpose of this article is to determine the performance of a reactive hyperemia test in the general population in terms of validity, increase in case identification, and test refusal; and to identify differences between the two major ways of expressing the results (the postocclusive ankle index and the percentage change in ankle systolic pressure). METHODS: Changes in ankle pressures were measured during reactive hyperemia in 1460 men and women aged 55 to 74 years, who were randomly sampled in the Edinburgh Artery Study. The validity of the test was determined in 91 cases identified by the presence of intermittent claudication and a low resting ankle pressure and in 91 controls matched by age and sex. RESULTS: The mean postocclusive ankle index was 0.98 (SD 0.20), and the mean drop in ankle pressure was 9.89% (SD 12.79%). In examining the validity of the test, differences occurred in the two ways of expressing the results: the postocclusive ankle index was 90% sensitive and 97% specific and the percentage drop in ankle pressure was 52% sensitive and 86% specific in detecting disease. The postocclusive ankle index increased the overall identification of cases in the Edinburgh Artery Study from 6.5% to 11.5%, but the percentage drop in ankle pressure increased identification to only 9.5%. Eight percent of subjects refused the test because of discomfort; this group contained more women, more elderly, and more obese subjects. CONCLUSIONS: The reactive hyperemia test is an appropriate test to use in the general population. The results are more accurate when expressed as the postocclusive ankle index rather than the percentage drop in ankle pressure.

Serum cholesterol, triglycerides, and aggression in the general population.

A higher than expected number of violent deaths and suicides in coronary prevention trials has provoked interest in the possibility that low serum cholesterol concentrations are associated in the general population with personality characteristics predisposing to aggressive and suicidal behaviour. We have investigated this possibility in the Edinburgh Artery Study. We measured serum lipid concentrations in blood samples taken from fasting subjects and assessed personality characteristics on the Bedford Foulds Personality Deviance Scales in a random sample of 1592 men and women aged 55-74 years, selected from age-sex registers of ten general practices in Edinburgh. Serum cholesterol concentration was not significantly associated with aggression in men, but it was associated in multivariate analysis (though not univariate analysis) with denigratory attitudes towards others among women. However, serum triglyceride concentration was related, especially in men, to hostile acts (r = 0.13, p < 0.001) and domineering attitude (r = 0.12, p < 0.001) independently of age, total and HDL cholesterol, cigarette smoking, and alcohol consumption. Subjects taking part in prevention trials have higher triglyceride concentrations than the general population and the relation between serum triglyceride concentration and aggression merits further investigation.