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The authors investigated the association of serum copper concentration with the risk of acute myocardial infarction in 1,666 randomly selected men aged 42, 48, 54, or 60 years who had no symptomatic ischemic heart disease at entry. Baseline examinations in the Kuopio Ischaemic Heart Disease Risk Factor Study in Eastern Finland were done during 1984 to 1988. In Cox multivariate survival models adjusting for age, examination year, ischemic electrocardiogram in exercise, maximal oxygen uptake, diabetes, family history of ischemic heart disease, cigarette-years, mean systolic blood pressure, serum high density lipoprotein (HDL) cholesterol subfraction HDL2 and low density lipoprotein (LDL) cholesterol concentrations and blood leukocyte count, serum copper concentration in the two highest tertiles (1.02-1.16 mg/liter and 1.17 mg/liter or more) associated with 3.5-fold (95% confidence interval (Cl) 1.3-9.4, p less than 0.05) and 4.0-fold (95 percent Cl 1.5-10.8, p less than 0.01) risk of acute myocardial infarction. These data indicate that high copper status, reflected by elevated serum copper concentration, is an independent risk factor for ischemic heart disease.

The association of past changes in serum cholesterol level with cause-specific mortality between 1974 and 1989 was examined in a cohort of 784 Finnish men aged 55-74 years who were free of symptomatic coronary heart disease in 1974. Changes in serum cholesterol level were computed based on measurements made in 1959, 1964, 1969, and 1974. Of the 405 deaths, 202 were due to cardiovascular diseases and 107 due to cancer. Men with a decline in serum cholesterol level between 1959 and 1974 also experienced greater than average declines in body mass index and tended to be more often current smokers in 1974. Among 339 men aged 65-74 years in 1974, men in the lowest tertile of serum cholesterol change, i.e., with greatest declines, had increased cardiovascular (hazard ratio, 1.58; 95% confidence interval 1.00-2.50) and all-cause (hazard ratio, 1.46; 95% confidence interval 1.06-2.02) mortality compared with men in the middle tertile of change, i.e., with least change, in multivariate analysis. Among 445 men aged 55-64 years in 1974, there was a significant U-shaped association between change in serum cholesterol level and coronary and all-cause mortality risk. The authors suggest that both the decline in serum cholesterol level and the associated high mortality may be caused by a third factor, such as increased prevalence of chronic diseases or other changes associated with aging. This would help to explain why several studies have not found an association of serum cholesterol with coronary risk among the elderly.

The development of hypertension care over the 10-year period 1972-1982 in North Karelia and a reference area was assessed using three separate random samples of the population aged 30-59 years. The results show a clear improvement in the blood pressure levels of the population and in the hypertension care in North Karelia between 1972 and 1977 when the activities of the hypertension program of the North Karelia Project were gradually implemented. Awareness of elevated blood pressure increased from 39% to 71% among men and from 60% to 87% among women. The proportion of men under antihypertensive drug treatment increased from 4% to 10% and that of women increased from 10% to 15%. After 1977, the hypertension care was maintained but no further improvements were observed in general blood pressure levels. An improvement in hypertension care started in the reference area later than in North Karelia. In spite of favorable changes, the blood pressure level of the population was still high in 1982, the mean casual value among men being 145/87 mmHg and that among women being 141/84 mmHg. It is obvious that further progress in hypertension care is needed.

The relation of leisure time and occupational physical activity to the risk of death from ischemic heart disease was investigated in a cohort of 15,088 persons aged 30-59 years who had no history of cardiovascular disease or other condition which hindered physical activity. Two population samples were randomly chosen from eastern Finland. During a six-year follow-up, persons who were sedentary in leisure time (relative risk = 1.3, 95% confidence interval (CI) = 1.1-1.6) or at work (relative risk = 1.3, 95% CI = 1.1-1.6) had an excess risk of ischemic heart disease death when adjusted for age, health status, family history, and body mass index in multivariate logistic models. Adjustment for years of education, social network participation, cigarette consumption, serum cholesterol level, and blood pressure level weakened the residual association of low leisure time physical activity with the risk of ischemic heart disease death (relative risk = 1.2, 95% CI = 1.0-1.5), whereas the association for low occupational physical activity remained unchanged. The lack of leisure time physical activity and a sedentary occupation are associated with an increased risk of ischemic heart disease death, and the excess risk due to lack of leisure time physical activity is, in part, accounted for by other ischemic heart disease risk factors.

As a part of the long-term prospective follow-up study conducted for women with genital human papillomavirus (HPV) infections in Kuopio University Hospital, Finland, since 1981, a case-control study was designed to assess risk factors for genital HPV infections. The cases (n = 691) were women who had been invited to attend the follow-up program on the basis of an abnormal cervical smear consistent with HPV-induced cytopathic changes, i.e., had a clinical HPV infection. The controls (n = 706) were a randomly selected group of women who had normal smears in the screening. Both groups were asked to fill in an extensive questionnaire focusing on detailed epidemiologic data on previous gynecologic and obstetric history, sexual practices, sexual partners, and smoking habits. In the multivariate analysis, eight variables emerged as independent risk factors for prevalent HPV infection. These variables could explain over 80% of the risk for infection. The risk for the infection varied with age, being highest in the age group 20-29 years, thereafter declining in the following 10-year age groups. The strongest independent risk factor was the number of sexual partners during the past 2 years (adjusted odds ratio = 12.1; 95% confidence interval 4.3-33.8 for five or more vs. one or no partners). Among the independent risk factors that increased the risk were also current smoking (adjusted odds ratio = 2.7; 95% confidence interval 1.7-4.3), warts in sexual partner(s) (adjusted odds ratio = 3.2; 95% confidence interval 1.6-6.5), and increasing frequency of sexual intercourse per week. Independent risk factors with a protective effect included a normal result in the last Papanicolaou smear, regular use of an intrauterine device as a contraceptive method, and good personal hygiene. No significant association between oral contraceptive use and risk for HPV infection was found. Condom use did not result in protection from the infection. The results of this study support the concepts that sexual intercourse is the main form of transmission among adults and that sexual promiscuity is the most important determinant for genital HPV infections.

The association between five socioeconomic indices (lifetime occupation, education, income, ownership of material possessions, and childhood socioeconomic status) and plasma fibrinogen levels was investigated in middle-aged Finnish men who were part of the Kuopio Ischemic Heart Disease Risk Factor Study. The Kuopio Ischemic Heart Disease Risk Factor Study is based on a representative age-stratified sample of 2,682 men aged 42, 48, 54, and 60 years. The data were collected between 1984 and 1989. The present analysis is restricted to the 2,011 men for whom information on fibrinogen and all covariates was available. The covariates were alcohol consumption, body mass index, physical fitness, smoking, coffee consumption, high density lipoprotein cholesterol, low density lipoprotein cholesterol, blood leukocyte count, and prevalent disease (at least one sign of ischemic heart disease, hypertension, diabetes, or previous stroke). An age-adjusted inverse association was found between levels of plasma fibrinogen and four of the five socioeconomic indices: current income, education, lifetime occupation status, and current material possessions. After adjustment for the covariates, the association persisted for education, current income, and lifetime occupation. Analysis of the joint effect of childhood and adult socioeconomic status indicated that those who were economically disadvantaged at both times had the highest fibrinogen levels, but the fibrinogen levels of those who were not poor as adults had no variation by childhood socioeconomic status.

The association between an a priori measure of social connections and five-year mortality from all causes, cardiovascular diseases (International Classification of Diseases, Eighth Revision (ICD-8) codes 390-458), and ischemic heart disease (ICD-8 codes 410-414) was studied in 13,301 men and women from eastern Finland who were first interviewed in 1972 or 1977. For men, there was a graded association between extent of social connections and mortality. In multivariate models with adjustment for age, smoking, serum cholesterol, mean weighted blood pressure, measures of prevalent illness, and other possible confounders, men who were in the two lowest quintiles of the social connections scale were at increased risk compared with those in the highest quintile (odds ratio (OR)all cause = 1.54, 95% confidence interval (CI) = 1.21-1.95; ORcardiovascular disease = 1.54, 95% CI = 1.11-2.13; ORischemic heart disease = 1.34, 95% CI = 0.94-1.90). No strong or consistent association was found for women. The association for men was modified by levels of blood pressure with the effect of low social connections greater at higher levels of blood pressure. In three separate analyses, there was no evidence for confounding or effect modification due to prevalent illness at baseline.

A matched-pair analysis was conducted with data based on a prospective six-year follow-up of a random population sample to study the association between serum selenium and the risk of cancer. Case-control pairs were from a population, after exclusions, of 8,113 persons examined in 1972 from two counties in eastern Finland. Cases were 31- to 59-year-old men and women initially free of cancer. One control was matched to each case according to age, gender, daily tobacco consumption, and serum cholesterol concentration. The mean serum selenium of the 128 cases was 50.5 micrograms/liter and that of the controls was 54.3 micrograms/liter (p = 0.012 for difference). When the residual variation in tobacco consumption and serum cholesterol as well as that in four other possible confounders was allowed for in a multiple logistic model, serum selenium of less than 45 micrograms/liter was associated with a relative risk of cancer of 3.1 (95% confidence interval, 1.5-6.7, p less than 0.01). These data support the hypothesis that selenium deficiency increases the risk of certain cancers in middle-aged persons.

The relationship of the risk of cancer and death to total serum cholesterol was studied in a random population sample from two counties of Eastern Finland. Data on total serum cholesterol were recorded between February and April 1972 for 3745 men and 4221 women aged 30 to 59 years who had no history of cancer, diabetes, or cardiovascular or cerebrovascular disease in the preceding 12 months. The participating rate in the survey was 92% in men and 94% in women. During six years from January 1, 1973 to December 31, 1978, cancer occurred in 65 men and 78 women at risk and 130 men and 52 women died of any disease. The risk of cancer bore no relationship to serum cholesterol either in men or in women. In men, the risk of death due to any disease and coronary heart disease rose steadily with increasing serum cholesterol from the level of 270 mg/dl (7.0 mmol/liter), whereas in women there was no association between serum cholesterol and the risk of death.

The potential benefits of a high-risk and a population strategy to prevent cardiovascular disease deaths by lowering total serum cholesterol and diastolic blood pressure were estimated. The first strategy concentrates on the top 10% of the risk distribution, and the second strategy changes risk factor distributions of the entire population. With the high-risk strategy, lowering total serum cholesterol 20% and diastolic blood pressure to 90 mmHg would result in a 28% reduction in death from cardiovascular disease. Lowering total serum cholesterol to 190 mg/dl and diastolic blood pressure to 80 mmHg with this strategy would result in a 33 per cent reduction in death from cardiovascular disease. These expected changes approximate those expected by lowering total serum cholesterol by 10% and diastolic blood pressure by 5% with the population strategy. Changes in total serum cholesterol (20% lowering) and diastolic blood pressure (10% lowering) that have been achieved in nutrition intervention trials would result in a 50% decline in cardiovascular disease death rates if applied to the whole population. If population mean total serum cholesterol could be lowered to 190 mg/dl and population mean diastolic blood pressure could be lowered to 80 mmHg, a 70% reduction in cardiovascular disease death rates would be expected. This suggests that only a population approach can prevent the majority of deaths from cardiovascular disease in a community.

A comprehensive community-based program to control cardiovascular disease was carried out in North Karelia, Finland, in 1972--1977. Reductions in smoking, serum cholesterol and blood pressure (BP) levels were among the central intermediate objectives. The effect was evaluated by examining independent population samples at the outset and at the end, both in the program area and in a matched reference area. More than 10,000 subjects were studied each time (participation rate about 90%). This paper presents the analyses of the estimated effect of the program on the risk factor means by comparing the baseline and terminal situations among the population aged 30--59 years. The effect of the program among men was estimated to be a reduction of 13% in smoking, 4% in serum cholesterol and 3% in systolic and diastolic BP means. Among women, there was a net reduction of 5% in systolic BP and 4% in diastolic BP means. The net reductions in smoking (8%) and serum cholesterol (1%) among women were within sampling variation. It is concluded that the population means of the major coronary heart disease risk factors were reduced during the program more in the intervention area than in the reference area, and it seems likely that most of this difference was due to the program.

Physical activity at work and in leisure time was studied by using a questionnaire in a random population sample from two counties of Eastern Finland in 1972. Data on age, serum cholesterol, diastolic blood pressure, height, weight and smoking were recorded in a field examination. The study population consisted of 3978 men aged 30-59 years and 3688 women aged 35-59 years. The participation rate was 92% in men and 94% in women in these age groups. During the approximately seven-year follow-up until December 31, 1978, 210 men and 63 women had an acute myocardial infarction (AMI), 89 men and 14 women died of acute ischemic heart disease, 71 men and 56 women had a cerebral stroke and 172 men and 75 women died of any disease. The subjects with a history of myocardial infarction, angina or cerebral stroke in the 12 months preceding the baseline survey were excluded in the respective analysis. Low physical activity at work was associated with an increased risk of AMI, cerebral stroke and death due to any disease in both men and women, even when controlling for age, serum total cholesterol, diastolic blood pressure, height, weight and smoking in a multiple logistic model. The relative risk of AMI was 1.5 (90% confidence interval (CI) = 1.2-2.0) in men and 2.4 (90% CI = 1.5-3.7) in women. Low physical activity in leisure time had a significant association with an increased risk of death, but not with an increased risk of AMI or stroke in the multivariate analysis.