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Objective: To examine relationships of normal blood pressure (BP), hypertension and degree of BP control with cardiovascular disease (CVD) risk factors and predicted 10-year risks for coronary heart disease (CHD) and stroke., Design: Cross-sectional survey., Setting: 107 Marks and Spencer retail stores in the UK., Participants: 14,077 women, aged 30-64 years, screened for CVD risk factors between 1988 and 1991., Main Outcome Measures: Systolic (SBP) and diastolic (DBP) BP; total, high-(HDL) and low-density lipoprotein (LDL) cholesterol, ratio of total to HDL cholesterol (TC/HDL-C); triglycerides, apolipoprotein A1, apolipoprotein B, lipoprotein (a), glucose, body mass index, antihypertensive medication and predicted risks for CHD and stroke. Hypertension was defined as SBP > or = 140 mmHg and/or DBP > or = 90 mmHg and/or taking anti-hypertensive medication. Subjects were divided into normotensives with optimal (n = 6,599), normal (n = 3,170) and high normal (n = 2,184) BP levels, and hypertensives with adequate BP control (n = 228), untreated (n = 1,729) and inadequate BP control (n = 291)., Results: BP level was associated with other CVD risk factors among both normotensives and hypertensives. Women with inadequately controlled BP had the worst risk profile, followed by untreated hypertensives, those with adequately controlled BP and normotensives. Odds ratios for being in the top quintile of predicted 10-year CHD and stroke risks were 1, 2.7, 4.2, 8.5, 13.0, 18.9 for CHD; 1, 1.1, 5.8, 18.7, 20.6, 756 for stroke, for optimal, normal, high normal, adequate BP control, untreated and inadequate BP control groups respectively., Conclusions: Untreated hypertensives and women taking anti-hypertensive medication but with BP > or = 140/90 mmHg have the most atherogenic risk factor profiles. Effective management of BP and the associated CVD risk requires a multi-factorial approach, rather than addressing BP control in isolation.

Plasma viscosity, molecular markers of activated coagulation and fibrinolysis (fibrinopeptides A and B beta 15-42), coagulation factors (fibrinogen and factor VII) and antiplasmins were measured in 529 men aged 35-54 years and related to new angina pectoris (n = 117) and to coronary risk factors in controls without angina (n = 412). Five major risk factors (cigarette-smoking, blood pressure, cholesterol, triglyceride and body mass index) were each associated with increases in plasma viscosity, coagulation factors, and imbalance of coagulation over fibrinolysis (increased ratio of fibrinopeptide A/fibrinopeptide B beta 15-42). Increased viscosity and fibrinogen in smokers were partly reversed in ex-smokers, but the imbalance of coagulation and fibrinolysis persisted. Cholesterol and triglyceride were also associated with increased antiplasmin activity. In men with angina, only fibrinogen was elevated compared to controls. We suggest that increased plasma viscosity and an imbalance of coagulation over fibrinolysis may be mechanisms by which known risk factors promote arterial thrombosis, but are not present in stable angina.

The relation between coronary heart disease (CHD) and fatty acid composition of adipose tissue and platelets was examined in a random sample of 448 middle-aged Scottish men. The linoleic acid (18:2n6) content in adipose tissue of 28 men with previously unidentified CHD was significantly lower than that in the rest of the group. Platelet linoleic and other fatty acids were not significantly different in men with new CHD. Fatty acid content of adipose tissue reflects long-term dietary intake, and a 7-day weighed dietary record in a random sub-sample of 164 men confirmed that intake of linoleic acid in 10 of the 28 new CHD cases was significantly lower than in the healthy men. In a multiple logistic analysis adipose tissue linoleic acid, age, high density lipoprotein cholesterol, and weight/height index each made an independent contribution to the explanation of new CHD. When all fatty acids were included in a second regression analysis, low concentrations of dihomo-gamma-linolenic (20:3n6) acid in adipose tissue showed a more significant relation with new CHD than did linoleic acid.

The relation between alcohol consumption and dietary intake was examined in 164 middle-aged Scottish men taking part in a study of risk factors for coronary heart disease (CHD). A 7-d weighed dietary record was used to assess alcohol and nutrient intake. The mean daily intake of alcohol was 26 g (SD 31 g). Energy derived from alcohol tended to replace energy derived from other nutrients and increasing intake of alcohol was associated with a decrease in the amounts of carbohydrate, total fat, and saturated and monounsaturated fatty acids in the diet. Those with a low alcohol intake (0.1-9 g alcohol/d) had a higher intake of total fiber, cereal fiber, polyunsaturated fatty acids, and linoleic acid and a smaller proportion smoked cigarettes. The differences are small but may contribute to the lower mortality from CHD reported by other studies in those with a low alcohol intake.

The relation between the fatty-acid composition of adipose tissue and platelet membranes and the estimated relative risk of coronary heart disease (CHD) was examined in a case-control study of new angina pectoris (AP) and first acute myocardial infarction (AMI). There were progressive inverse relations between adipose linoleic acid and platelet-membrane eicosapentaenoic acid and the estimated relative risk of AP. These relations were statistically independent of each other and traditional CHD risk factors. For AMI there was a progressive inverse relation between adipose linoleic acid and the estimated relative risk, but it was confounded by smoking habit. Smokers consume less linoleic acid than non-smokers. Although eicosapentaenoic acid in platelet membranes was lower in AMI patients than in controls, this difference was not significant. The estimated proportionate increase in risk of AP, independent of other CHD risk factors, was 1.2 (1.1-1.3) for a 1% decrease in linoleic acid or a 0.1% decrease in eicosapentaenoic acid.

Cross-cultural studies suggest that low plasma antioxidant levels contribute to the high incidence of coronary heart disease (CHD) in Scotland. One hundred twenty-five cases of angina without reported history were identified by a postal WHO chest pain questionnaire from a systemic population sample of 6000 Edinburgh men (35-54 years). Classical CHD risk factors (lipids, blood pressure, smoking, and relative weight), plasma vitamins, and a new independent CHD risk factor, adipose tissue linoleate, were measured in angina (n = 125) and healthy controls (n = 430). Cigarette smoking was common in angina (46% vs. 29%, p less than 0.01), and adipose tissue linoleate was lower (8.77 +/- 0.18% vs. 9.81 +/- 0.14% (p less than 0.01). Classical CHD risk factors were not different. Vitamin E/cholesterol molar ratio (micron/mM) was lower in angina than in controls: 1.58 +/- 0.03 vs. 1.66 +/- 0.02 (p less than 0.01). Plasma vitamin C was also lower in angina than in controls: 23.6 +/- 1.7 vs. 30.5 +/- 1.1 microM (p less than 0.001). The relative risk of angina for those in the lowest versus those in the highest quintile of the vitamin E/cholesterol ratio distribution was 2.2:1, irrespective of other risk factors (p less than 0.009). Adipose tissue linoleate removed the association between vitamin E and angina. The relative risk of angina for those in the lowest versus those in the highest quintile of plasma vitamin C was 2.6:1 (p less than 0.01), and the increased risk was also independent of classical risk factors, but closely related to a smoking habit. Low plasma vitamin E or adipose linoleate predisposes to angina, and smoking may increase the risk of angina by lowering plasma vitamin C levels in Scottish men.

The possibility of an inverse relation between essential fatty acids in adipose tissue, in particular linoleic acid, and mortality from coronary heart disease was studied by a cross sectional survey of random population samples of apparently healthy men aged 40-49 from four European regions with differing mortality from coronary heart disease. The proportion of linoleic acid in adipose tissue was lowest in men from north Karelia, Finland, where mortality from coronary heart disease is highest, and highest in men from Italy, where mortality is lowest, with intermediate proportions in men from Scotland and south west Finland. Similar gradients were observed for the desaturation and elongation products dihomo-gamma-linolenic and arachidonic acid. The proportion of saturated fatty acids in adipose tissue was highest in Finland, intermediate in Scotland, and lowest in Italy. Italian men also had the highest proportion of oleate in their adipose tissue and the lowest proportion of myristoleate and palmitoleate. Finnish men were more obese and had a higher blood pressure. Serum cholesterol concentration was higher in north Karelia and south west Finland than in Scotland or Italy. High density lipoprotein (HDL) cholesterol concentrations reflected the regional differences in serum cholesterol, being higher in Finland and lower in Italy. The ratios of HDL cholesterol to total cholesterol, however, did not differ. The regional differences in linoleic acid in adipose tissue remained highly significant when the observed differences in other known risk factors for coronary heart disease among the four areas were taken into account by multivariate analysis. The gradients in proportions of polyunsaturated fatty acids probably reflect differences in dietary intake of linoleic acid.