Identifying men at high risk of heart attacks: strategy for use in general practice.

A strategy was devised for identifying men at high risk of acute myocardial infarction or sudden ischaemic death. A risk score was devised using cigarette smoking, mean blood pressure, recall of ischaemic heart disease or diabetes mellitus diagnosed by a doctor, history of parental death from "heart trouble," and the presence of angina reported on a questionnaire. The top fifth of the score distribution identified 53% of ischaemic heart disease cases--that is, men who subsequently experienced major ischaemic heart disease over the next five years. The addition of serum total cholesterol concentration and electrocardiographic evidence only slightly improved prediction (to 59%) and would have considerably increased the cost and effort of screening. Using this risk score on an opportunistic basis could be particularly valuable in general practice. Management of this high risk group is regarded as appropriate medical care and is complementary to the population approach to preventing ischaemic heart disease. Such a strategy for reducing the incidence of and mortality from ischaemic heart disease in men at high risk would also increase professional and public awareness of the need for preventive action.     

Environmental tobacco smoke exposure and ischaemic heart disease: an evaluation of the evidence.

OBJECTIVES: To estimate the risk of ischaemic heart disease caused by exposure to environmental tobacco smoke and to explain why the associated excess risk is almost half that of smoking 20 cigarettes per day when the exposure is only about 1% that of smoking. DESIGN: Meta-analysis of all 19 acceptable published studies of risk of ischaemic heart disease in lifelong non-smokers who live with a smoker and in those who live with a non-smoker, five large prospective studies of smoking and ischaemic heart disease, and studies of platelet aggregation and studies of diet according to exposure to tobacco smoke. RESULTS: The relative risk of ischaemic heart disease associated with exposure to environmental tobacco smoke was 1.30 (95% confidence interval 1.22 to 1.38) at age 65. At the same age the estimated relative risk associated with smoking one cigarette per day was similar (1.39 (1.18 to 1.64)), while for 20 per day it was 1.78 (1.31 to 2.44). Two separate analyses indicated that non-smokers who live with smokers eat a diet that places them at a 6% higher risk of ischaemic heart disease, so the direct effect of environmental tobacco smoke is to increase risk by 23% (14% to 33%), since 1.30/1.06 = 1.23. Platelet aggregation provides a plausible and quantitatively consistent mechanism for the low dose effect. The increase in platelet aggregation produced experimentally by exposure to environmental tobacco smoke would be expected to have acute effects increasing the risk of ischaemic heart disease by 34%. CONCLUSION: Breathing other people''s smoke is an important and avoidable cause of ischaemic heart disease, increasing a person''s risk by a quarter.     

Hemorheologic findings in patients with ischemic heart disease

The paper deals with the rheological properties of the blood of 38 male patients affected by ischaemic heart diseases (age: 40-75 years) and 19 healthy test persons of comparable age. The following haemorheological properties were measured. 1. Relative plasma viscosity 2. Erythrocyte aggregation 3. Erythrocyte deformability 4. Thrombocyte aggregation and 5. Whole blood viscosity. For the purpose of representing and assessing the results of measurement obtained a division was made into different groups according to the appearances of ischaemic heart disease (chronic ischaemic heart disease, unstable angina pectoris, acute heart infarct) and risk factors (smoking, diabetes mellitus, blood high pressure and hyperlipidaemia). The methods 1-3 proved to be especially suitable for representing gradual differences in the examined rheological parameters. The results obtained are discussed and evaluated.     

Decline in ischaemic heart disease in Iceland and change in risk factor levels.

OBJECTIVE--To monitor trends in mortality and morbidity due to ischaemic heart disease and compare these with observed levels of risk factors from population surveys. DESIGN--Analysis of trends in death rates from ischaemic heart disease in Iceland compared with expected rates computed from population surveys. Risk factor levels together with beta factors obtained from Cox''s regression analysis were used to compute expected death rates. Trends in morbidity due to acute myocardial infarction were assessed and secular trends in dietary consumption compared with trends in cholesterol concentrations. SETTING--Reykjavik, Iceland (total population 250,000; over half the population live in Reykjavik). SUBJECTS--12,814 randomly selected residents in the Reykjavik area aged 45-64 (6623 men, 6191 women; 72% and 80% of those invited). MAIN OUTCOME MEASURES--Age adjusted rates of myocardial infarction and deaths from ischaemic heart disease. Expected risk from risk factor levels (smoking, total serum cholesterol concentration, systolic blood pressure) at each unique survey visit. RESULTS--Mortality from ischaemic heart disease has decreased by 17-18% since 1970. During 1981-6 the myocardial infarction attack rate in men under 75 decreased by 23%. A decrease occurred in the level of all three major risk factors after 1968. The fall in the serum cholesterol concentration coincided with a reduction in consumption of dairy fat and margarine. The calculated reduction in risk for the age group 45-64 was about 35%, which was closely similar to the observed decrease in mortality due to ischaemic heart disease in that age group. CONCLUSION--The reduction in mortality from ischaemic heart disease was substantially due to a decreased incidence of myocardial infarction and could be attributed largely to the reduction in risk factors.     

Depression as a risk factor for ischaemic heart disease in men: population based case-control study

Objective: To determine the relation between depression, anxiety, and use of antidepressants and the onset of ischaemic heart disease. Design: Population based case-control study. Setting: All 5623 patients registered with one general practice. Subjects: 188 male cases with ischaemic heart disease matched by age to 485 male controls without ischaemic heart disease; 139 female cases with ischaemic heart disease matched by age to 412 female controls. Main outcome measure: Adjusted odds ratios calculated by conditional logistic regression. Results: The risk of ischaemic heart disease was three times higher among men with a recorded diagnosis of depression than among controls of the same age (odds ratio 3.09; 95% confidence interval 1.33 to 7.21; P=0.009). This association persisted when smoking status, diabetes, hypertension, and underprivileged area (UPA(8)) score were included in a multivariate model (adjusted 2.75; 1.13 to 6.69; P=0.03). Men with depression within the preceding 10 years were three times more likely to develop ischaemic heart disease than were the controls (3.13; 1.27 to 7.70; P=0.01). Men with ischaemic heart disease had a higher risk of subsequent ischaemic heart disease than men without ischaemic heart disease (adjusted 2.34; 1.34 to 4.10; P=0.003). Depression was not a risk factor for ischaemic heart disease in women on multivariate analysis (adjusted 1.34; 0.70 to 2.56; P=0.38). Anxiety and subsequent ischaemic heart disease were not significantly associated in men or women. Conclusion: Depression may be an independent risk factor for ischaemic heart disease in men, but not in women.

Key messages

• So far, research into whether depression precedes myocardial infarction has been limited
• This case-control study examined the relation between ischaemic heart disease and depression and the differences in this relation between men and women
• Depression may be a risk factor for ischaemic heart disease in men but not women
• This is independent of diabetes, hypertension, deprivation score, and smoking status

     

Snoring as a risk factor for ischaemic heart disease and stroke in men.

The association of snoring with ischaemic heart disease and stroke was studied prospectively in 4388 men aged 40-69. The men were asked, in a questionnaire sent to them, whether they snored habitually, frequently, occasionally, or never. Hospital records and death certificates were checked for the next three years to establish how many of the men developed ischaemic heart disease or stroke: the numbers were 149 and 42, respectively. Three categories of snoring were used for analysis: habitual and frequent snorers (n = 1294), occasional snorers (n = 2614), and non-snorers (n = 480). The age adjusted relative risk of ischaemic heart disease between habitual plus frequent snorers and non-snorers was 1.91 (p less than 0.01) and for ischaemic heart disease or stroke, or both, 2.38 (p less than 0.001). There were no cases of stroke among the non-snorers. Adjustment for age, body mass index, history of hypertension, smoking, and alcohol use did not significantly decrease the relative risks, which were 1.71 (p greater than 0.05) for ischaemic heart disease and 2.08 (p less than 0.01) for ischaemic heart disease and stroke combined. At the beginning of follow up in 1981, 462 men reported a history of angina pectoris or myocardial infarction. For them the relative risk of ischaemic heart disease between habitual plus frequent snorers and non-snorers was 1.30 (NS); for men without previous ischaemic heart disease 2.72 (p less than 0.05). Snoring seems to be a potential determinant of risk of ischaemic heart disease and stroke.     

ABO blood group and ischaemic heart disease in British men.

OBJECTIVE--To establish whether ABO blood group is related to ischaemic heart disease on an individual and geographic basis in Britain. DESIGN--Prospective study of 7662 men with known ABO blood group selected from age-sex registers in general practices in 24 British towns. MEASUREMENTS--ABO blood group, standard cardiovascular risk factors, social class, and presence or absence of ischaemic heart disease determined at entry to study. END POINTS--Eight year follow up of fatal and nonfatal ischaemic heart disease events achieved for 99% of study population. RESULTS--Towns with a higher prevalence of blood group O had higher incidences of ischaemic heart disease. In individual subjects, however, the incidence of ischaemic heart disease was higher in those with group A than in those with other blood groups (relative risk 1.21, 95% confidence limits 1.01 to 1.46). Total serum cholesterol concentration was slightly higher in subjects of blood group A. No other cardiovascular risk factor (including social class) was related to blood group. CONCLUSIONS--Blood group A is related to the incidence of ischaemic heart disease in individual subjects. Geographic differences in the distribution of ABO blood groups do not explain geographic variation in rates of ischaemic heart disease in Britain. The findings do not support the view that ABO blood group and social class are related.     

Change in alcohol consumption and risk of death from all causes and from ischaemic heart disease.

OBJECTIVE--To examine the association between alcohol consumption and mortality from all causes and from ischaemic heart disease with a focus on differentiating between long term abstainers and more recent non-drinkers. DESIGN--Cohort study of changes in alcohol consumption from 1965 to 1974 and mortality from all causes and ischaemic heart disease during 1974-84. SETTING--Population based study of adult residents of Alameda County, California. SUBJECTS--2225 women and 1845 men aged 35 and over in 1965. MAIN OUTCOME MEASURES--Alcohol consumption in 1964 and 1974 and mortality from all causes and from ischaemic heart disease during 1974-84. RESULTS--There was a significantly higher risk of death from all causes and from ischaemic heart disease in women who gave up drinking between 1965 and 1974 than in women who continued to drink (relative risk 1.72, 95% confidence interval 1.11 to 2.66, and 2.75, 1.44 to 5.23, for all causes and ischaemic heart disease respectively). A significant increase in risk was not seen in men who gave up drinking (1.32, 0.87 to 2.01, and 0.95, 0.41 to 2.20, respectively). Among men, long term abstainers compared with drinkers were at increased risk of death from all causes and from ischaemic heart disease, though the associations were not significant (1.40, 0.98 to 2.00, and 1.40, 0.76 to 2.58, for all causes and ischaemic heart disease respectively). CONCLUSION--Some of the increased risk of death from all causes and from ischaemic heart disease associated with not drinking in women seems to be accounted for by higher risks among those who gave up drinking. Men who are long term abstainers may also be at an increased risk of death. The heterogeneity of the non-drinking group should be considered when comparisons are made with drinkers.     

Mortality from ischaemic heart disease among patients using anticonvulsive drugs: a case-control study.

Patients who use phenytoin and some other anticonvulsive drugs have been shown to have raised concentrations of plasma high density lipoprotein. As this lipoprotein is known to be inversely associated with the incidence of ischaemic heart disease the causes of death of all patients with epilepsy known to be taking anticonvulsive drugs who died during 1978-80 were studied. Of 1399 deaths of anticonvulsant users, 258 (18.4%) were caused by ischaemic heart disease. This was significantly less (p less than 0.001) than the 382 deaths from ischaemic heart disease (27.3%) observed among paired controls matched for sex, age, and date of death. The total cardiovascular mortality was also lower among patients with epilepsy than among controls (p less than 0.02) despite there being more deaths due to cerebrovascular disease among patients. The difference in mortality from ischaemic heart disease was significant for both sexes and was not accounted for by excess deaths due to any other single cause. Users of phenytoin, carbamazepine, and barbiturates (alone or in combination) showed 29% less mortality due to ischaemic heart disease than respective controls (p less than 0.001).     

Alcohol consumption,serum low density lipoprotein cholesterol concentration,and risk of ischaemic heart disease: six year follow up in the Copenhagen male study.

OBJECTIVES: To investigate the interplay between use of alcohol, concentration of low density lipoprotein cholesterol, and risk of ischaemic heart disease. DESIGN: Prospective study with controlling for several relevant confounders, including concentrations of other lipid fractions. SETTING: Copenhagen male study, Denmark. SUBJECTS: 2826 men aged 53-74 years without overt ischaemic heart disease. MAIN OUTCOME MEASURE: Incidence of ischaemic heart disease during a six year follow up period. RESULTS: 172 men (6.1%) had a first ischaemic heart disease event. There was an overall inverse association between alcohol intake and risk of ischaemic heart disease. The association was highly dependent on concentration of low density lipoprotein cholesterol. In men with a high concentration (> or = 5.25 mmol/l) cumulative incidence rates of ischaemic heart disease were 16.4% for abstainers, 8.7% for those who drank 1-21 beverages a week, and 4.4% for those who drank 22 or more beverages a week. With abstainers as reference and after adjustment for confounders, corresponding relative risks (95% confidence interval) were 0.4 (0.2 to 1.0; P<0.05) and 0.2 (0.1 to 0.8; P<0.01). In men with a concentration <3.63 mmol/l use of alcohol was not associated with risk. The attributable risk (95% confidence interval) of ischaemic heart disease among men with concentrations > or = 3.63 mmol/l who abstained from drinking alcohol was 43% (10% to 64%). CONCLUSIONS: In middle aged and elderly men the inverse association between alcohol consumption and risk of ischaemic heart disease is highly dependent on the concentration of low density lipoprotein cholesterol. These results support the suggestion that use of alcohol may in part explain the French paradox.     

Changes in risk factors explain changes in mortality from ischaemic heart disease in Finland.

OBJECTIVES--To estimate the extent to which changes in the main coronary risk factors (serum cholesterol concentration, blood pressure, and smoking) explain the decline in mortality from ischaemic heart disease and to evaluate the relative importance of change in each of these risk factors. DESIGN--Predicted changes in ischaemic heart disease mortality were calculated by a logistic regression model using the risk factor levels assessed by cross sectional population surveys, in 1972, 1977, 1982, 1987, and 1992. These predicted changes were compared with observed changes in mortality statistics. SETTING--North Karelia and Kuopio provinces, Finland. SUBJECTS--14,257 men and 14,786 women aged 30-59 randomly selected from the national population register. MAIN OUTCOME MEASURES--Levels of the risk factors and predicted and observed changes in mortality from ischaemic heart disease. RESULTS--The observed changes in the risk factors in the population from 1972 to 1992 predicted a decline in mortality from ischaemic heart disease of 44% (95% confidence interval 37% to 50%) in men and 49% (37% to 59%) in women. The observed decline was 55% (51% to 58%) and 68% (61 to 74) respectively. CONCLUSION--An assessment of the data on the risk factors for ischaemic heart disease and mortality suggests that most of the decline in mortality from ischaemic heart disease can be explained by changes in the three main coronary risk factors.     

Type A behaviour and ischaemic heart disease in middle aged British men.

The Bortner questionnaire, which measures aspects of type A (coronary prone) behaviour was completed by 5936 men aged 40-59 selected at random from one general practice in each of 19 British towns. The presence of ischaemic heart disease was determined at initial examination and the men were followed up for an average of 6.2 years for morbidity and mortality from myocardial infarction and for sudden cardiac death. Non-manual workers had significantly higher scores (more type A) than manual workers and the score decreased (less type A) with increasing age. After adjustment for social class and age men with higher scores had higher prevalences of ischaemic heart disease less marked for electrocardiographic evidence and more marked for response to a chest pain questionnaire (angina or possible myocardial infarction). A man''s recall of a doctor''s diagnosis of ischaemic heart disease, however, did not relate to his Bortner score. There was no significant relation between the Bortner score and the attack rate or incidence of major ischaemic heart disease events. In this study type A behaviour, as measured by the Bortner questionnaire, did not predict major ischaemic heart disease events in British middle aged men.     

Helicobacter pylori infection and mortality from ischaemic heart disease: negative result from a large,prospective study.

OBJECTIVE: To determine whether there is an independent association between Helicobacter pylori infection of the stomach and ischaemic heart disease. DESIGN: Prospective study with measurement of IgG antibody titres specific to H pylori on stored serum samples from 648 men who died from ischaemic heart disease and 1296 age matched controls who did not (nested case-control design). SUBJECTS: 21,520 professional men aged 35-64 who attended the British United Provident Association (BUPA) medical centre in London between 1975 and 1982 for routine medical examination. MAIN OUTCOME MEASURE: Death from ischaemic heart disease. RESULTS: The odds of death from ischaemic heart disease in men with H pylori infection relative to that in men without infection was 1.06 (95% confidence interval 0.86 to 1.31). In a separate group of 206 people attending the centre, plasma fibrinogen was virtually the same in those who were positive for H pylori (2.62 g/l) and those who were negative (2.64 g/l). CONCLUSIONS: A study that by its size and design minimised both random error and socioeconomic bias found no relation between H pylori infection and ischaemic heart disease. The validity of the study was shown by its confirmation of the recognised association between H pylori infection and stomach cancer (odds ratio 4.0 (1.9 to 8.2); P < 0.001). Eradication of H pylori infection may greatly reduce the incidence of stomach cancer, one of the most common causes of death from cancer worldwide, but it cannot be expected to have any effect in preventing ischaemic heart disease.     

Alcohol and ischaemic heart disease in middle aged British men.

The relation between alcohol intake and ischaemic heart disease was examined in a large scale prospective study of middle aged men drawn from general practices in 24 British towns. After an average follow up of 6.2 years 335 of the 7729 men had experienced a myocardial infarction (fatal or non-fatal) or sudden cardiac death. No significant relation was found between reported alcohol intake and the incidence of such events. Though the group of light daily drinkers had the lowest incidence of ischaemic heart disease events, it also contained the lowest proportion of current smokers, had the lowest mean blood pressure, had the lowest mean body mass index, and contained the lowest proportion of manual workers. These characteristics are more likely to account for the apparent protective effect of alcohol against ischaemic heart disease than a direct effect of alcohol. Compared with the effects of established risk factors alcohol seems to be quite unimportant in the development of ischaemic heart disease.     

By how much and how quickly does reduction in serum cholesterol concentration lower risk of ischaemic heart disease?

OBJECTIVE--To estimate by how much and how quickly a given reduction in serum cholesterol concentration will reduce the risk of ischaemic heart disease. DESIGN--Data on the incidence of ischaemic heart disease and serum cholesterol concentration were analysed from 10 prospective (cohort) studies, three international studies in different communities, and 28 randomised controlled trials (with mortality data analysed according to allocated treatment to ensure the avoidance of bias). MAIN OUTCOME MEASURE--Decrease in incidence of ischaemic heart disease or mortality for a 0.6 mmol/l (about 10%) decrease in serum cholesterol concentration. RESULTS--For men results from the cohort studies showed that a decrease of serum cholesterol concentration of 0.6 mmol/l (about 10%) was associated with a decrease in incidence of ischaemic heart disease of 54% at age 40 years, 39% at age 50, 27% at 60, 20% at 70, and 19% at 80. The combined estimate from the three international studies (for ages 55-64 years) was 38% (95% confidence interval 33% to 42%), somewhat greater than the cohort study estimate of 27%. The reductions in incidence of ischaemic heart disease in the randomised trials (for ages 55-64 years) were 7% (0 to 14%) in the first two years, 22% (15% to 28%) from 2.1-5 years, and 25% (15% to 35%) after five years, the last estimate being close to the estimate of 27% for the long term reduction from the cohort studies. The data for women are limited but indicate a similar effect. CONCLUSIONS--The results from the cohort studies, international comparisons, and clinical trials are remarkably consistent. The cohort studies, based on half a million men and 18,000 ischaemic heart disease events, estimate that a long term reduction in serum cholesterol concentration of 0.6 mmol/l (10%), which can be achieved by moderate dietary change, lowers the risk of ischaemic heart disease by 50% at age 40, falling to 20% at age 70. The randomised trials, based on 45,000 men and 4000 ischaemic heart disease events show that the full effect of the reduction in risk is achieved by five years.     

Phobic anxiety and ischaemic heart disease.

A prospective study of the relation between scores on the six subscales of the Crown-Crisp experiential index and subsequent incidence of ischaemic heart disease was undertaken among participants in the Northwick Park heart study. Results from 1457 white men aged 40-64 at recruitment showed that phobic anxiety was strongly related to subsequent major ischaemic heart disease (fatal and non-fatal events combined) when other associated variables were taken into account. The phobic anxiety score alone remained significantly associated with ischaemic heart disease when scores on all the subscales were included in the analysis. Phobic anxiety seemed to be particularly associated with fatal ischaemic heart disease but was not associated with deaths from other causes and was no higher in those with a pre-existing myocardial infarction at recruitment than in those without. There was a consistent increase in risk of fatal ischaemic heart disease with score on the phobic anxiety subscale. The relative risk for those whose score was 5 and above was 3.77 (95% confidence interval 1.64 to 8.64) compared with those whose score was 0 or 1. The 49 participants with evidence of myocardial infarction at recruitment had higher scores on the subscales for free floating anxiety and functional somatic complaint. The Crown-Crisp experiential index is simple to fill out and acceptable to patients. When the results are combined with other known risk factors it may be of use in defining high risk subjects and in planning strategies for prevention.     

Travel and ischaemic heart disease.

The hypothesis that travel precipitates acute ischaemic heart disease (IHD) was tested in a case-control study of holidaymakers admitted to hospital in Great Yarmouth. The distance that patients with IHD had travelled to reach Great Yarmouth was on average greater than that travelled by patients with other diseases. I conclude that the greater distances travelled by patients with IHD may have helped to precipitate the attack.     

Mortality in two radom samples of women aged 55-64 followed up for 20 years.

Two random samples of women aged 55-64 living in the Vale of Glamorgan and the Rhondda Fach were followed up for 20 years. In each sample heights, weights, serum cholesterol concentrations, and specific causes of death were noted and the Quetelet index (weight/height2) calculated. The two samples were combined for analysis of total mortality. In the combined sample there was a strong positive association between Quetlet index and both total mortality and mortality from ischaemic heart disease. Multiple logistic regression analysis showed that both of these associations were significant, as was the strong positive association between Quetelet index and mortailty from ischaemic heart disease in the samples considered separately. There was no significant association between cholesterol concentration and mortality from ischaemic heart disease in each sample. There was a small negative association between cholesterol concentration and both total mortaility in the combined sample and ischaemic heart disease in the Rhondda Fach sample. These results suggest that the Quetelet index is important for prognosis, whereas the serum cholesterol concentration is not.     

Cardiovascular State of Newly Discovered Diabetic Women

A cardiovascular study of a group of 90 newly diagnosed diabetic women aged 35 to 75 years was begun in 1965 and a repeat examination was carried out on the same patients in 1968. A high prevalence of ischaemic heart disease was found in these patients at the time of diagnosis, and this finding had some predictive value as regards prognosis over the three-year period.A comparative study with general medical outpatients and long-established diabetics (greater than 10 years'' duration of disease) confirmed the high prevalence of ischaemic heart disease in late-onset mild diabetics controlled by diet or oral drugs. It is suggested that this type of milder diabetic patient contributes in undue proportion to the high prevalence of ischaemic heart disease in diabetes.