Sven Punsar

The Seven Countries Study : 2,289 deaths in 15 years

Among 11,579 men ages 40-59 without evidence of cardiovascular disease, 2,289 died in 15 years, 618 from coronary heart disease. The 15 cohorts in seven countries (four regions) differed in all-causes death rate, mainly reflecting great differences in coronary mortality. Among characteristics of entry, only mean blood pressure helped to explain cohort differences in all-causes death rate. Three-quarters of the variance in coronary death rate was accounted for by differences in mean serum cholesterol and blood pressure of the cohorts. The mortality risk for individuals was examined in each of the regions. For coronary death, age, serum cholesterol, blood pressure, and smoking were highly significant in all regions except Japan, where coronary deaths were too few for evaluation. Relative weight was not significant anywhere. Physical activity was significant only in southern Europe, where differences are associated with socioeconomic status. For all-causes death, age and blood pressure were highly significant risk factors in all regions as was smoking habit, except in Japan. Relative body weight tended to be a negative risk factor everywhere, significantly so in southern Europe. Expectations for coronary death from the experience in the United States and northern Europe greatly exceeded observed deaths in southern Europe for men of their age, serum cholesterol, blood pressure, smoking habits, physical activity, and relative weight. The reverse, prediction of coronary deaths in America and in northern Europe from the southern European experience, greatly underestimated the deaths observed. Similar cross-predictions between the United States and northern Europe were good for all-causes deaths, excellent for coronary deaths. Analysis of time trends in relationships of mortality to entry characteristics showed continued importance of age, blood pressure, and smoking and a tendency for the importance of cholesterol to fall in the last 5 years of follow-up.

REDUCTION OF PREMATURE MORTALITY BY HIGH PHYSICAL ACTIVITY: A 20-YEAR FOLLOW-UP OF MIDDLE-AGED FINNISH MEN

The association of physical activity level with the risk of death was analysed for a cohort of 636 healthy Finnish men aged 45-64 years followed up for 20 years. 39% of the cohort were classed as highly active physically at baseline in 1964. Up to 1984 there were 287 deaths, 106 of them due to coronary heart disease (CHD). During the first-two thirds of the follow-up, men with high physical activity had a lower risk of death than did men with low physical activity. During the last third, the survival curves of the men with high and low physical activity gradually converged. Of the men who died, those with high physical activity lived 2.1 years longer (p = 0.002) than those with low physical activity, after adjustment for age, smoking, blood pressure, serum cholesterol, and body mass index. This difference was due mainly to fewer CHD deaths among the highly active group. Low physical activity was clearly weaker than smoking as a predictor of risk of death. High physical activity may thus independently prevent premature death among middle-aged men, but it probably does not prolong the maximum achievable life-span.

Glucose tolerance and coronary heart disease: Helsinki Policemen Study

Abstract The relationship of glucose tolerance to the prevalence of symptoms and ECG signs of coronary heart disease (CHD), and to the 10-yr mortality from all causes, cardiovascular diseases and CHD was investigated in 867 Helsinki policemen aged 40–59 on whom an oral glucose tolerance test was carried out in 1966–1967. An oral glucose load of 75 or 90 g according to body surface area was used and blood glucose was determined fasting, 1 and 2 hr after the glucose load. Fasting and post-load blood glucose levels did not show any definite relationship to the prevalence of CHD symptoms (angina pectoris, history of verified myocardial infarction, non-verified severe chest pain attack) at the time of the initial examination, but these blood glucose variables showed a trend to a positive association to the prevalence of ischaemic ECG abnormalities. In multivariate analyses including age, systolic blood pressure, plasma cholesterol, body mass index and smoking, the blood glucose variables, however, failed to show a significant independent relationship to the prevalence of ECG abnormalities. In univariate analyses, a positive non-linear relationship was found between the blood glucose variables and the 10-yr mortality from all causes, cardiovascular diseases and CHD. The mortality rates were significantly higher in the top quintiles or deciles of 1-hr and 2-hr post-load blood glucose levels than in the corresponding combined lower quantiles. Fasting blood glucose showed similar trends, though these were not statistically significant. In multivariate analyses including age, systolic blood pressure, plasma cholesterol, body mass index and smoking, the blood glucose variables, however, did not show a significant independent contribution in the prediction of the 10-yr mortality from all causes, cardiovascular diseases or CHD.

Comparison of Multivariate Predictive Power of Major Risk Factors for Coronary Heart Diseases in Different Countries: Results from Eight Nations of the Seven Countries Study, 25-Year Follow-up

BACKGROUND It was hypothesized that among eight national groups of men aged 40-59 years enrolled in the Seven Countries Study, the multivariate coefficients of major risk factors predicting coronary heart disease mortality over 25 years would be relatively similar. MATERIALS AND METHODS Sixteen cohorts were located in eight nations and pooled, comprising one cohort in the USA, two in Finland, one in the Netherlands, three in Italy, two in Croatia (former Yugoslavia), three in Serbia (Yugoslavia), two in Greece and two in Japan, for a total of over 12000 subjects at entry. Coronary heart disease (CHD) mortality was defined as fatal myocardial infarction or sudden coronary death, and proportional hazard models were solved, for each country, with age, serum cholesterol level, systolic blood pressure and cigarette consumption as covariates. RESULTS The relationships between risk factors and CHD mortality were statistically significant for all risk factors and for all countries, except for age in Croatia and Japan, cholesterol in Croatia and Japan, systolic blood pressure in Serbia and Greece, and cigarette-smoking in the Netherlands, Croatia, Serbia and Greece. When comparing all pairs of coefficients (28 comparisons for each factor) significant differences were found on four occasions for age, on six occasions for cholesterol, on no occasion for blood pressure and on four occasions for cigarette-smoking. Other tests suggested a substantial homogeneity among multivariate coefficients. Estimates for pooled coefficients were: age, in years, 0.0570 (95% confidence limits 0.0465 and 0.0673); relative risk for 5 years 1.33 (95% confidence limits 1.26 and 1.40); serum cholesterol level in mg/dl, 0.0057 (95% confidence limits 0.0045 and 0.0069); relative risk for 40 mg/dl 1.31 (95% confidence limits 1.20 and 1.31); systolic blood pressure in mmHg, 0.0160, (95% confidence limits 0.0134 and 0.0185), relative risk for 20 mmHg 1.38 (95% confidence limits 1.31 and 1.45); cigarettes per day, 0.0220 (95% confidence limits 0.0170 and 0.0272); relative risk for 10 cigarettes per day 1.25 (95% confidence limits 1.18 and 1.31). CONCLUSIONS Great similarities were found in the multivariate coefficients of major coronary risk factors to CHD risk derived from population samples varying in CHD frequency.

Subendocardial Haemorrhage and E.C.G. Changes in Intracranial Bleeding

E.C.G. changes in connexion with intracranial (especially subarachnoidal) bleeding resembling those in myocardial infarction were first described by Burch et al. in 1954. The most typical change is a deep and broad T-U fusion wave in several leads. The explanation of the changes observed remains obscure (Effert et al., 1961). The purpose of this paper is to discuss the genesis of these E.C.G. changes on the basis of three cases in which both the typical E.C.G. changes and subendocardial haemorrhages

Seven Countries Study. First 20-Year Mortality Data in 12 Cohorts of Six Countries

Out of the original 16 cohorts in the Seven Countries Study on Cardiovascular Diseases, 12 population samples in six countries have reached the 20 year follow-up deadline. Data on mortality became fully available for a total of 8287 men aged 40-59 at entry examination (two cohorts in Finland, one in the Netherlands, three in Italy, two in Yugoslavia, two in Greece, and two in Japan). Death rates from CHD as well as from all causes follow the traditional falling north to south trend (18 fold between the extremes for CHD; 2.7 fold for total mortality). The differences in all causes mortality are, however, largely accounted for by the variation in CHD mortality. The mean entry levels of serum cholesterol and representative levels of the consumption of saturated fats, mono-unsaturated fats, poly-unsaturated fats and carbohydrates explain a large proportion of inter-cohort difference in CHD mortality (81% for saturated fats). By applying the proportional hazards model to the pools of national cohorts, with CHD deaths as end-point and five risk factors as covariates, only age and mean blood pressure are universally significant predictors of fatal events. Cholesterol, smoking habits, body mass index and physical activity play some part but not in all the pools. Age and mean blood pressure are also the only universal risk factors for all causes of death.

Serum selenium and risk of cancer: a prospective follow-up of nine years

The association between serum selenium concentration and the risk of cancer was studied in 1110 men aged 55 to 74 years in two rural areas of Finland. The men were followed‐up prospectively for 9 years and there were 109 new cases of cancer, with the cases of the first follow‐up year excluded. The serum selenium concentrations were adjusted for age, area, smoking, serum cholesterol, and alcohol intake. The patients had a slightly lower adjusted mean serum selenium than the subjects without cancer at the end of the follow‐up (±standard error of mean) 53.9 ± 1.5 and 55.3 ± 0.5 μg/1, respectively. The relative risks of cancer were essentially the same when these were calculated in the tertiles of the serum selenium distribution. Thirty‐seven men had a history of cancer at baseline or had cancer diagnosed during the first follow‐up year and their adjusted mean serum selenium was 49.4 ± 2.6 μg/1, which was significantly lower (P<0.05) than that of the subjects without cancer during the follow‐up.

Coronary heart disease and drinking water: A search in two Finnish male cohorts for epidemiologic evidence of a water factor☆

A search for the hypothetical factor in drinking water that might influence the mortality from C.H.D. was made in two rural areas in western and eastern Finland. A 10-yr follow-up of the resident males had shown a higher death rate from C.H.D. in the eastern area. The difference is only partly explained by the currently known risk factors of C.H.D. The levels of 22 water characteristics were investigated in 327 wells and six tap-water samples. In both areas the water used for drinking is soft but the mean concentrations of several components differ. In general, the concentrations are lower in the eastern area. The difference is significant for pH, F, Ca, Mg, Na, and Cr. The concentrations of NO3, K, Cu, Co, Ni, and Ba are significantly higher in the eastern area. In both populations there were indications that death from, or the development of, C.H.D. was connected with the quality of the water, particularly with low concentrations of constituents. Assuming that a single water constituent is responsible for the difference in mortality from C.H.D. between the cohorts, the elements most suspect were chromium and, to a lesser degree, copper. C.H.D. was associated with low concentrations of chromium and high concentrations of copper in drinking water. Findings on magnesium were equivocal, and no association was observed with calcium. The relationships of the components of drinking water to the following risk factors of death from C.H.D. were also investigated: systolic blood pressure, serum cholesterol, extrasystoles in ECG, and cigarette smoking. In the eastern area the concentration of serum cholesterol correlated negatively with the concentration of chromium in drinking water.

Smoking, carbon monoxide, and atherosclerotic diseases.

Smoking habits and random measurements of the proportion of haemoglobin bound to carbon monoxide (COHb%) were examined for their association with atherosclerotic diseases in 1068 men aged 55 to 74 years from rural areas of Finland. COHb% and smoking history were similarly associated with claudication and coronary heart disease. Random measurements of COHb% did not show a better overall relation to the prevalence of atherosclerotic diseases than smoking history, though COHb% showed a stronger association with a probable previous myocardial infarction. Further studies are needed to clarify the role of carbon monoxide in atherosclerosis.

Asymptomatic autoimmune thyroiditis and coronary heart disease. Cross sectional and prospective studies

Cross sectional and prospective surveys of thyroid autoimmunity have been performed in two cohorts of men, 280 living in west Finland and 269 in east Finland. In both populations, aged 50 to 69 years at the first survey, risk factors for coronary heart-disease (C.H.D.) were common. The incidence of C.H.D. was shown to be related to the presence of thyroid antibodies. The results of the cross-sectional studies were not conclusive. The five-year follow-up study emphasised that in both areas asymptomatic thyroid autoimmunity, independently of other known risk factors, was a predictor of subsequent development of C.H.D. The importance of asymptomatic autoimmune thyroid-itis as a risk factor for C.H.D. increases with age.