Cigar and pipe smoking and myocardial infarction in young men.

The effect of cigar and pipe smoking on the risk of myocardial infarction was evaluated in an interview study of 572 men with non-fatal first myocardial infarctions and 934 hospital controls. The study was conducted in the north eastern United States from 1980 to 1983. All subjects were 40-54 years of age, and none had smoked cigarettes for at least two years. Among men who had never smoked cigarettes the relative risk of myocardial infarction for those who smoked at least five cigars a day, compared with not smoking cigars and pipes and allowing for other risk factors, was estimated to be 1.7 (95% confidence interval 0.6 to 4.8). Among ex-smokers of cigarettes the corresponding estimate for those who smoked at least five cigars a day was 4.5 (2.2 to 9.2). The estimates for men who smoked fewer cigars, or pipes, were closer to 1.0 and not significant. Men who stop smoking cigarettes and switch to at least five cigars a day apparently continue to have an increased risk of myocardial infarction, possibly because they continue to inhale the smoke.     

Does stopping smoking delay onset of angina after infarction?

This study was designed to determine the relation between stopping smoking and angina after infarction in survivors of an acute coronary attack. The study population comprised 408 men aged under 60 who survived a first attack of unstable angina or myocardial infarction by 28 days and were smoking cigarettes at the time of their attack. These patients were followed up for an average of nine years. Three hundred and eighty four were alive at the one year follow up examination, when the presence or absence of angina together with habits of smoking were recorded. The prevalence of angina at one year was 19.5% in the 241 who had stopped smoking cigarettes compared with 32.2% in those who had continued (p less than 0.01). Six years later, however, the prevalence of angina after infarction was the same in the two groups. It is concluded that the onset of angina after infarction can be delayed by stopping smoking cigarettes but that this effect is not maintained in the long term.     

Long term effect on mortality of stopping smoking after unstable angina and myocardial infarction.

Subjects who stop smoking cigarettes after myocardial infarction have an improved rate of survival compared with those who continue, but to date it was not known whether the benefit persisted for more than six years. A total of 498 men aged under 60 years who had survived a first episode of unstable angina or myocardial infarction by two years were followed up by life table methods for a further 13 years. Mortality in those who continued to smoke was significantly higher (82.1%) than in those who stopped smoking (36.9%). These differences increased with time. Mortality in those who were non-smokers initially and who continued not to smoke was intermediate (62.1%). The adverse effect of continued smoking was most pronounced in those with unstable angina. Continuing to smoke increased the rate of sudden death to a greater degree in those with less severe initial attacks, while the effect of smoking on fatal reinfarctions was most apparent in those with a more complicated presentation. These findings suggest that stopping cigarette smoking is the most effective single action in the management of patients with coronary heart disease.     

Vitamin C deficiency and risk of myocardial infarction: prospective population study of men from eastern Finland.

OBJECTIVE: To examine the association between plasma vitamin C concentrations and the risk of acute myocardial infarction. DESIGN: Prospective population study. SETTING: Eastern Finland. SUBJECTS: 1605 randomly selected men aged 42, 48, 54, or 60 who did not have either symptomatic coronary heart disease or ischaemia on exercise testing at entry to the Kuopio ischaemic heart disease risk factor study in between 1984 and 1989. MAIN OUTCOME MEASURES: Number of acute myocardial infarctions; fasting plasma vitamin C concentrations at baseline. RESULTS: 70 of the men had a fatal or non-fatal myocardial infarction between March 1984 and December 1992.91 men had vitamin C deficiency (plasma ascorbate < 11.4 mumol/l, or 2.0 mg/l), of whom 12 (13.2%) had a myocardial infarction; 1514 men were not deficient in vitamin C, of whom 58 (3.8%) had a myocardial infarction. In a Cox proportional hazards model adjusted for age, year of examination, and season of the year examined (August to October v rest of the year) men who had vitamin C deficiency had a relative risk of acute myocardial infarction of 3.5 (95% confidence interval 1.8 to 6.7, P = 0.0002) compared with those who were not deficient. In another model adjusted additionally for the strongest risk factors for myocardial infarction and for dietary intakes of tea fibre, carotene, and saturated fats men with a plasma ascorbate concentration < 11.4 mumol/l had a relative risk of 2.5 (1.3 to 5.2, P = 0.0095) compared with men with higher plasma vitamin C concentrations. CONCLUSIONS: Vitamin C deficiency, as assessed by low plasma ascorbate concentration, is a risk factor for coronary heart disease.     

High mean platelet volume after myocardial infarction: is it due to consumption of small platelets?

Seventy nine men surviving after sustaining a myocardial infarction in 1982, and who had at that time had raised mean platelet volumes compared with controls, were followed up after 18 months. The shape of each man''s platelet distribution curve was calculated from the mean platelet volume, platelet count, and platelet distribution width. The calculated curves were in close agreement with the curves plotted by the Coulter counter from the raw data. These curves did not differ significantly from those of a current control group, but the curves plotted from the variables measured at the time of myocardial infarction in 1982 showed a deficit of platelets in the volume range 5-12 fl amounting at maximum to 30% (p less than 0.0001); there were no significant differences above 12 fl. The deficit of small platelets became more appreciable during initial admission, was less at one month''s follow up, and had disappeared at one year. The deficit of small platelets is probably an effect rather than a cause of infarction.     

Myocardial infarction: a comparison between home and hospital care for patients.

To compare the results of home and hospital treatment in men aged under 70 years who had suffered acute myocardial infarction within 48 hours 1895 patients were considered for study in four centres in south-west England. Four-hundred-and-fifty patients were randomly allocated to receive care either at home by their family doctor or in hospital, initially in an intensive care unit. The randomised treatment groups were similar in age, history of cardiovascular disease, and incidence of hypotension when first examined. They were followed up for up to a year after onset. The mortality rate at 28 days was 12% for the random home group and 14% for the random hospital group; the corresponding figures at 330 days were 20% and 27%. On average, older patients and those without initial hypotension fared rather better under home care. The patients who underwent randomisation were similar to those whose place of care was not randomised, except that the non-randomised group contained a higher proportion of initially hypotensive patients, whose prognosis was poor wherever treated. These results confirm and extend our preliminary findings. Home care is a proper form of treatment for many patients with acute myocardial infarction, particularly those over 60 years and those with an uncomplicated attack seen by general practitioners.     

Sexual activity after myocardial infarction.

Questionnaires on sexual activity were completed by 161 patients attending an exercise-centred rehabilitation program an average of some 3 years after a myocardial infarction. In almost half the group, sexual activity was unchanged or increased compared with the period before the infarction. In the remainder it was reduced; this group included 29 men who had adopted a more passive sexual role and 26 who were now having angina or ventricular premature beats during intercourse. Although the patients with diminished activity could not be distinguished by means of formal personality test, questionnaires completed by their wives suggested that they were less willing to assume responsibility, had increased difficulty in adjusting to life at home and at work and were more neurotic and depressed than those with normal or increased activity. Furthermore, those with decreased sexual activity had a poorer response to training in terms of attendance, final average jogging distance and gains in physiologic status. Since the frequency of angina and ventricular premature beats was less during intercourse than during standard laboratory exercise, it was concluded that normal sexual relations carry no special risk for the average postcoronary patient; indeed, by enhancing self-esteem and encouraging effective participation in an exercise programm, acceptance of normal sexual activity may improve the prognosis.     

Tobacco and myocardial infarction: is snuff less dangerous than cigarettes?

OBJECTIVE--To estimate the risk of myocardial infarction in snuff users, cigarette smokers, and non-tobacco users in northern Sweden, where using snuff is traditional. DESIGN--Case-control study. SETTING--Northern Sweden. SUBJECTS--All 35-64 year old men who had had a first myocardial infarction and a population based sample of 35-64 year old men who had not had an infarction in the same geographical area. MAIN OUTCOME MEASURE--Tobacco consumption (regular snuff dipping, regular cigarette smoking, non-tobacco use) and risk of acute myocardial infarction. RESULTS--59 of 585 (10%) patients who had a first myocardial infarction and 87 of 589 (15%) randomly selected men without myocardial infarction were non-smokers who used snuff daily. The age adjusted odds ratio for myocardial infarction was 0.89 (95% confidence interval 0.62 to 1.29) for exposure to snuff and 1.87 (1.40 to 2.48) for cigarette smoking compared with non-tobacco users, showing an increased risk in smokers but not in snuff dippers. Regular cigarette smokers had a significantly higher risk of myocardial infarction than regular snuff dippers (age adjusted odds ratio 2.09; 1.39 to 3.15). Smoking, but not snuff dipping, predicted myocardial infarction in a multiple logistic regression model that included age and level of education. CONCLUSIONS--In middle aged men snuff dipping is associated with a lower risk of myocardial infarction than cigarette smoking.     

Psychological rehabilitation after myocardial infarction.

The value of psychological counselling in rehabilitating patients after myocardial infarction was assessed. A total of 143 men who had recently had a myocardial infarction were randomly allocated to either a group receiving intensive rehabilitation or a control group, their outcome being examined after six months. Patients with neurotic, introverted personalities had a poor outcome in the control group but a satisfactory outcome when rehabilitated. Neurotic personalities responded to help, and rehabilitative measures did not increase neurosis. In addition all patients with a negative attitude towards their illness and future had a poor outcome but those with a positive attitude did well. Selection by simple methods of patients who would benefit from psychological rehabilitation seems desirable.     

Lipoprotein (a) and coronary heart disease: a prospective case-control study in a general population sample of middle aged men.

OBJECTIVE--To examine the association between the serum lipoprotein (a) concentration and subsequent coronary heart disease. DESIGN--Prospective case-control study based on a six year follow up of a general population sample of men aged 50 at baseline in 1983-4. Serum samples were frozen at the time of the baseline examination and kept at -70 degrees C for six years, after which the lipoprotein (a) concentrations in the samples were measured in cases and controls. SETTING--City of Gothenburg, Sweden. SUBJECTS--26 Men, from a general population sample of 776 men, who had sustained a myocardial infarction or died of coronary heart disease during the six years and 109 randomly selected controls from the same sample who had remained free of myocardial infarction. In neither cases nor controls was there a history of myocardial infarction at baseline. MAIN OUTCOME MEASURES--Proportion of myocardial infarction or deaths from coronary heart disease, or both, in relation to the serum lipoprotein (a) concentration. RESULTS--Men who suffered coronary heart disease had significantly higher serum lipoprotein (a) concentrations than controls (mean difference 105 mg/l; 95% confidence interval 18 to 192 mg/l). Men with the highest fifth of serum lipoprotein (a) concentrations (cut off point 365 mg/l) suffered a coronary heart disease rate which was more than twice that of men with the lowest four fifths of concentrations. Logistic regression analysis showed the serum lipoprotein (a) concentration to be significantly associated with coronary heart disease independently of other risk factors. CONCLUSION--The serum lipoprotein (a) concentration in middle aged men is an independent risk factor for subsequent myocardial infarction or death from coronary heart disease.     

How well can we predict coronary heart disease? Findings in the United Kingdom Heart Disease Prevention Project.

The probability of myocardial infarction developing over five years in a group of middle aged men was predicted with knowledge of their ages, blood pressures, cholesterol concentrations, and smoking habits as recorded in an initial screening examination. Although the top 15% of the risk distribution predicted 115 (32%) of the subsequent cases of myocardial infarction, there was a considerable overlap in predicted risk between those subjects who did and those who did not go on to develop a myocardial infarction. Of the subjects in the top 15% of risk, only 72 (7%) of those initially free of coronary heart disease and 43 (22%) of those initially with coronary heart disease actually developed a myocardial infarction over the subsequent five years. Thus, although a group of subjects at high risk can be identified, among whom will be a high proportion of potential victims of heart attack, many subjects will be wrongly classified. These findings may explain part of the difficulty in persuading patients of the potential benefits of reducing risks and highlight the need for research to improve the prediction of the development of coronary heart disease.     

Increase in blood glucose concentration during antihypertensive treatment as a predictor of myocardial infarction: population based cohort study

ObjectiveTo investigate the impact of an increase in blood glucose on the risk of developing myocardial infarction, with particular emphasis on people taking antihypertensive drugs.DesignProspective population based cohort study.SettingUppsala, Sweden.Participants1860 men who had participated in 1970-3 at age 50 in a health survey aimed at identifying risk factors for cardiovascular disease and were re-examined at age 60 and then followed for 17.4 years.ResultsThe incidence of myocardial infarction was significantly higher in men treated for hypertension than in those without such treatment (23% v 13.5%, P<0.0001). Participants who developed myocardial infarction after the age of 60 (n=253) showed a significantly larger increase in blood glucose between age 50 and 60 than did those without myocardial infarction. In multivariate Cox proportional hazard models increase in blood glucose was an independent risk factor for myocardial infarction (P=0.0001) in men receiving antihypertensive treatment at age 60 (n=291, mainly β blockers and thiazide diuretics) but not in those without such treatment. The impact of increase in blood glucose declined after inclusion of serum proinsulin concentrations at baseline but was still significant. A significant interaction existed between proinsulin concentration (a marker of insulin resistance) at baseline and antihypertensive treatment on increase in blood glucose.ConclusionsIncrease in blood glucose between the ages of 50 and 60 and baseline proinsulin concentration were important risk factors for myocardial infarction in men receiving antihypertensive treatment, indicating that both an insulin resistant state and the metabolic impact of β blockers and diuretics increase the risk of myocardial infarction.

What is already known on this topic

Patients with hypertension are resistant to insulin stimulated glucose uptake and are hyperinsulinaemic compared with normotensive controlsTreatment with β blockers and thiazide diuretics further increases insulin resistance, thereby increasing the risk of developing type 2 diabetes mellitus or impaired glucose toleranceThe influence of metabolic changes induced by antihypertensive treatment on the risk of myocardial infarction has been questioned

What this study adds

Men who received antihypertensive treatment showed a larger increase in blood glucose during a 10 year period than those without such treatmentIncrease in blood glucose during antihypertensive treatment was a significant, independent risk factor for myocardial infarction in men with an insulin resistant state at baseline     

Ischaemic Heart Disease in Young Women

The mortality rate from ischaemic heart disease (I.H.D.) has increased in young women by about 50% in 12 years, and it is now possible to report the findings in 150 women who developed symptoms and signs of I.H.D. under the age of 45. Data obtained from 145 of these women form the basis of this report: 81 presented with myocardial infarction and 64 with angina. In the remaining five there was a definite nonatherosclerotic cause for the premature onset of I.H.D.Hypercholesterolaemia, hypertension, or excessive cigarette smoking each occurred in a large minority, and more than one of these major risk factors was present in most patients. Hypercholesterolaemia was the commonest factor. In women in whom lipoprotein typing was undertaken the type II pattern was more frequent than type IV. The prevalence of hypercholesterolaemia and hypertension was the same in those with myocardial infarction and in those with angina.Excessive cigarette smoking was more common in women with myocardial infarction than in those with angina. The latter did not differ in their cigarette smoking habits from the normal population.A premature menopause had occurred in 20% of these women, but there was no relation between the early onset of I.H.D. with age at menarche, parity, or the incidence of abortion. Oral contraceptives did not increase the risk of myocardial infarction unless one of the major risk factors was also present.Altogether 75% of patients with angina or myocardial infarction survived 12 years. Coexisting hypertension worsened the prognosis. The prognosis after myocardial infarction was similar in these women to that previously described for men under the age of 40.     

Reduced risk of death at 28 days in patients taking a beta blocker before admission to hospital with myocardial infarction.

OBJECTIVE--To see whether patients taking an oral beta blocker at the time of admission to hospital with myocardial infarction have a reduced risk of death at 28 days. DESIGN--Retrospective analysis of data collected on patients admitted over four years. SETTING--Community based study. PATIENTS--2430 Consecutive patients living in the Perth statistical division admitted to hospital with myocardial infarction during 1984-7. MAIN OUTCOME MEASURE--Survival at 28 days among patients taking a beta blocker at onset of myocardial infarction. RESULTS--Patients were grouped into those who were and were not taking a beta blocker at the time of admission. Though patients taking a beta blocker were older and more likely to have a history of myocardial infarction, angina, or hypertension, the overall mortality at 28 days was similar in the two groups. A logistic regression model used to adjust for factors predictive of cardiac death at 28 days confirmed that patients taking a beta blocker at the time of admission had a significantly reduced risk of death (relative risk 0.50; 95% confidence interval 0.34 to 0.76). Though the incidence of fatal ventricular fibrillation was similar in the two groups, mean peak creatine kinase activity was significantly lower in the beta blocker group. CONCLUSIONS--These data support the value of long term use of beta blockers in patients at risk of myocardial infarction. They suggest that patients taking these agents before admission to hospital with myocardial infarction have a significant survival advantage at 28 days, which may be due to a reduction in infarct size.     

MYOCARDIAL INFARCTION FOLLOWING CAROTID ENDARTERECTOMY

Myocardial infarction has been the major cause of mortality following operation for cerebrovascular insufficiency. In our institution, a clinical diagnosis of coronary artery disease was made in 37 of 125 (29.6%) consecutive male patients having carotid endarterectomy. Six of these 37 patients developed postoperative myocardial infarction. In contrast, none of the 88 patients without coronary artery disease developed myocardial infarction. A more recently treated group of 20 patients who had undergone carotid artery surgery and had previously undergone coronary artery bypass for angina did not develop postoperative myocardial infarction. These data suggest that in patients with both coronary artery and carotid artery disease, prior or concomitant coronary artery bypass should be considered. Myocardial infarction has been the leading cause of early and late death following operation for cerebrovascular insufficiency.(1) DeBakey(2) found operative mortality in patients having surgery for cerebrovascular insufficiency directly related to the incidence of coronary artery disease. An increased operative mortality due to reinfarction has been found in patients recovering from recent myocardial infarction.(3) Cooley(4) found that in patients having aortocoronary bypass there was no increased operative mortality 30 days after myocardial infarction and this may apply to patients having carotid endarterectomy. Subendocardial postoperative infarction associated with minor T wave changes and slight enzyme elevation had a better prognosis than did transmural infarction causing significant Q waves, sequential ST and T wave changes and marked enzyme elevations.(5) The purpose of this study was to document our experience with myocardial infarction in patients undergoing carotid artery operation for clinical coronary artery disease. Consideration of the role of saphenous vein bypass in those patients with coronary artery disease was the background for this review even though the evidence that myocardial infarction can be prevented with saphenous vein bypass operation is only preliminary at the present time.(6)     

Unsuspected exposure to asbestos and bronchogenic carcinoma.

Two hundred and fifty men admitted to a thoracic surgical centre and matched controls were questioned in detail about their occupations after leaving school and their smoking habits. Of 201 men with confirmed bronchial carcinoma 58 gave a history of occupational exposure to asbestos, whereas only 29 out of 201 men matched for age and residential area who were admitted with other diseases gave such a history. This difference was statistically highly significant. The usual association of bronchial carcinoma with heavy smoking was observed, but asbestos exposure increased the risk of carcinoma whatever the level of smoking. These results are consistent with the hypothesis that asbestos exposure and the level of smoking act independently in causing bronchial carcinoma. The patients with carcinoma who had been exposed to asbestos presented on average three years earlier than those who had not been exposed. Asbestos regulations have eliminated the risk of exposure to workers in scheduled industries, so asbestos-induced diseases will probably be increasingly found among the many workers who have had incidental exposure to asbestos. It is therefore important to take a full occupational history.     

Alcohol intemperance and sudden death.

Ten years after a health screening examination was offered to 50 year old men 32 of the 2322 participants and 12 of the 454 nonparticipants had died of ischaemic heart disease. Of these, 26 and 11 respectively had suffered sudden death, for which necropsy was performed. Half of the men who had died suddenly had been registered for alcohol intemperance up to 1973, which was four times the prevalence of such registrations in the general population. Registration at both the Swedish Temperance Board and the Bureau of Social Services was associated with an odds ratio of 3.74 for sudden death as compared with not being registered at either. Logistic analysis including the classical risk factors for ischaemic heart disease together with registration for alcohol intemperance and at the Bureau of Social Services showed only the two types of registration and systolic blood pressure to be independent risk factors. On the other hand, there was no overrepresentation of subjects entered in the registers among those surviving a myocardial infarction. For non-fatal myocardial infarction blood pressure and serum triglyceride concentration were significant risk factors and serum cholesterol concentration, smoking, and body mass index probable risk factors; the two types of registration were not independent risk factors. Alcohol intemperance is strongly associated with an increased risk of sudden death after myocardial infarction.     

Course of angina pectoris after an acute coronary event.

The course of postcoronary angina pectoris was examined in 555 men who had survived a first attack of myocardial infarction or unstable angina. Patients were aged less than 60 and were followed up yearly for up to 17 years. Only 25 (4.5%) had coronary artery bypass surgery. Most patients with angina were treated by nitrates alone. One year after infarction 24.1% of survivors (124/515) reported the presence of angina pectoris, and the proportions at five, 10, and 15 years were 29.9%, 30.4%, and 43.5% respectively. Seventeen years after the initial event 35.3% of the survivors had never reported postcoronary anginal symptoms. The patients who experienced anginal symptoms in the year after their coronary attack had a poorer long term survival than the group who were symptom free over the first year. These patients also had longer subsequent periods with angina, though in 41.7% angina resolved before death after a median of 2.9 years. Throughout follow up mortality during periods in which patients experienced angina was higher than in the symptom free periods. This long term follow up study of patients after a coronary event confirms that the presence or absence of angina may vary considerably over time in patients treated medically and that the presence of angina is associated with a poorer prognosis. These findings have important implications when assessing the effects of various treatment modalities on postcoronary angina, including coronary artery bypass surgery.     

Early identification of patients at low risk of death after myocardial infarction and potentially suitable for early hospital discharge.

OBJECTIVES--To find (a) whether data available shortly after admission for acute myocardial infarction can provide a reliable prognostic indicator of survival at 28 days, and (b) whether such an indicator might be used to identify patients at low risk of death and suitable for early discharge. DESIGN--Retrospective analysis of data collected on patients admitted to a coronary care unit for acute myocardial infarction. A validation sample was selected at random from these patients. SETTING--Coronary care units in Perth, Western Australia. SUBJECTS--6746 patients aged under 65 and resident in the Perth Statistical Division who during 1984-92 were admitted to a coronary care unit with symptoms of myocardial infarction. MAIN OUTCOME MEASURES--Sensitivity and specificity of several models for predicting survival at 28 days after myocardial infarction, and detailed performance characteristics of a particular model. RESULTS--Patients with a pulse rate of 100 beats/min or less, aged 60 or under, and with symptoms typical of myocardial infarction, no past history of myocardial infarction or diabetes, and no significant Q wave in the admission electrocardiogram had a very high chance of survival at 28 days (99.2%). These patients made up one third of all patients studied. CONCLUSION--The prognostic index identifies patients very soon after admission who are at low risk of death and potentially eligible for early discharge from hospital or the coronary care unit. Computing the index does not need complex cardiac investigations.     

Low dietary intake of linoleic acid predisposes to myocardial infarction

Thirty-two men who had recently had a myocardial infarction were matched individually for age with controls who had no evidence of heart disease. The patients had a significantly lower proportion of linoleic acid and a higher proportion of palmitic acid in their plasma triglyceride fatty acids. Analysis of the composition of red-cell membrane phosphatidyl choline, which reflects long-term dietary fat intake, showed a significantly lower proportion of linoleic acid in the patients.These differences suggest that the type of dietary fat consumed might be an important factor in the genesis of ischaemic heart disease.