Incidence and presentation of myocardial infarction in North Karelia, Finland

Incidence, pre-hospital delay and prognosis of acute myocardial infarction in big regions of Hungary: Population data from the Hungarian myocardial infarction registry

AIM

To examine the incidence and treatment of acute myocardial infarction (AMI) as well as 30-day and 1-year prognoses of patients in different regions of Hungary. According to the statistical system of the European Union, Hungary can be divided into three major socio-economic regions-west Hungary, central Hungary and east Hungary.

METHODS AND RESULTS

The Hungarian Myocardial Infarction Registry (HUMIR) is a prospective comprehensive and mandatory disease registry for patients with AMI. The total population of Hungary is currently 9.8 million: 39% live in the eastern region (ER), 31% in the central region (CR) and 30% in the western region (WR). Population over 30 years, the age-standardised incidence of AMI was 177.5 (175.7-179.3) per 100 000 person-year. During hospital treatment, 82.5%-84.6% of patients with ST-elevation (STEMI) and 54.8%-58.8% without ST-elevation (NSTEMI) myocardial infarction underwent PCI. The total ischaemic time of patients with STEMI was shortest in WR (221 minutes) compared with two other regions (CR: 225 minutes and ER: 262 minutes). In the STEMI group, the 30-day mortality rates of male patients were lowest in the WR (P = .03). If PCI was performed, mortality rates for both sexes were lowest in the WR (P < .01; P = .04). The 1-year mortality rate in the male population who received PCI was lowest in the WR. In the NSTEMI group, the 30-day mortality rate exhibited no differences. Regarding 1-year mortality, those who underwent PCI in the WR showed the lowest mortality.

CONCLUSION

The major regions of Hungary revealed significant differences regarding the incidence, prehospital delay, treatment and mortality of AMI. Logistic regression analysis confirmed the independent prognostic significance of the region on the 30-day mortality of patients with STEMI (hazard ratio = 0.88, P = .0114; CI: 0.80-0.97).

Myocardial Infarction Register in MONICA-Czechoslovakia Centre

In 1984, 802 coronary events (age 25-64) were registered in six MONICA areas in Czechoslovakia. According to the MONICA study criteria, 63% of these coronary events in males and 51% in females were confirmed as definite myocardial infarction (MI), 26% of events in both males and females as possible MI, 5% of events in males and females were fetal cases with insufficient data, and 6% of events in males and 18% in females were not confirmed as MI (MONICA diagnostic category = 4). Age-standardized annual attack rates of MI per 100,000 population (age 35-64) were 510.4 for males and 99.3 for females. Age-standardized annual incidence rates (first ever MI) per 100,000 population (age 35-64) were 387.4 for males and 89.7 for females. 28-day case fatality was 33.3% in males and 31.5% in females. Of all deaths occurring within 28 days, 75.8% in males and 69.2% in females occurred during the first 24 hours. Of all coronary deaths, 38.5% of males and 64.1% of females died in hospital or other institution.

Comparison of the levels of cardiovascular risk factors between eastern and south-western Finland in 1982

Altogether 6,523 persons aged 25-64 years were studied in eastern and south-western Finland to determine their cardiovascular risk factor levels. Among men, smoking was more prevalent in the south-western area (41 vs. 37%), serum cholesterol levels were higher in the eastern area (6.2 vs. 6.0 mmol/l) and blood pressure levels were the same in both areas (145/86 in the east vs. 144/86 in the south-west). Among women, smoking was also more common in the south-western area (24 vs. 16%) and serum cholesterol levels were higher in the eastern area (6.1 vs. 6.0 mmol/l) as well as blood pressure levels (142/84 vs. 138/81 mmHg). Among both genders, prevalence of hypertension and proportion of persons on antihypertensive drug therapy was higher in eastern Finland. The comparison of these findings with the results from previous studies carried out among men in these two areas indicates that the risk factor levels have been decreasing in both areas and that the previously observed differences in risk factor levels between eastern and south-western Finland (the levels used to be higher in the east) have levelled off. The favourable development in eastern Finland may be a result of the North Karelia Project.

Cardiovascular risk factor changes in a three-year follow-up of a cohort in connection with a community programme (the North Karelia Project)

A re-examination after 3 years was done in 1975 in a 20% random subsample (n = 1683) of the representative population sample (males and females, 25-59 years) that was examined in 1972 in North Karelia (NK), and a matched reference county as the baseline survey for the community programme in NK. The changes in smoking habits, serum cholesterol, dietary fat consumption and systolic BP were more favourable among the subjects in the NK sample than among the reference sample, although the differences were generally small. Results from multivariable analyses are presented to show the variables that predict a favourable risk factor change in the individual. Living in NK is associated in the analysis with a favourable change in each of the three risk factors. The limitation of this method in the evaluation of a community programme is discussed.

Risk Attitudes and Behavior Among Norwegian Adolescents

Abstract. The core aim of the present study is to compare the effects of a safety campaign and a behavior modification program on traffic safety. As is the case in community-based health promotion, the present study's approach of the attitude campaign was based on active participation of the group of recipients. One of the reasons why many attitude campaigns conducted previously have failed may be that they have been society-based public health programs. Both the interventions were carried out simultaneously among students aged 18-19 years in two Norwegian high schools (n = 342). At the first high school the intervention was behavior modification, at the second school a community-based attitude campaign was carried out. Baseline and posttest data on attitudes toward traffic safety and self-reported risk behavior were collected. The results showed that there was a significant total effect of the interventions although the effect depended on the type of intervention. There were significant differences in attitude and behavior only in the sample where the attitude campaign was carried out and no significant changes were found in the group of recipients of behavior modification.

Comparison of trends in ischaemic heart disease between North Karelia, Finland, and Kaunas, Lithuania, from 1971 to 1987

OBJECTIVE

To compare the long-term trends in mortality and attack rate of ischaemic heart disease in North Karelia, Finland, and in Kaunas, Lithuania, from 1971 to 1987.

DESIGN

Data on routine mortality statistics were obtained from the Central Statistical Office of Finland and from the Central City Archives of Kaunas. In addition, data from the community based myocardial infarction registers were used. The registers used similar diagnostic criteria and had operated in both areas during the entire study period.

SETTING

The province of North Karelia in Finland and the city of Kaunas in Lithuania.

SUBJECTS

The target populations were the people of North Karelia and Kaunas aged 35-64 years.

MAIN OUTCOME MEASURES

Mortality from ischaemic heart disease and the attack rate of acute myocardial infarction.

RESULTS

In North Karelia mortality from ischaemic heart disease and the attack rate of acute myocardial infarction declined steeply both in men and women. This decline was accompanied by a decrease in total mortality. In Kaunas, both mortality and the attack rate increased in men but remained unchanged in women. In 1985 to 1987, age standardised total mortality per 100,000 inhabitants was similar in the two populations in men (1081 (95% confidence interval (CI) 1013 to 1149), in North Karelia; 1082 (95% CI 1032 to 1132), in Kaunas). The proportional mortality from ischaemic heart disease was considerably higher in North Karelia (40%) than in Kaunas (28%). In women, age standardised total mortality was lower in North Karelia (350 (95% CI 312-388)) than in Kaunas (440 (95% CI 413 to 467)). The proportional mortality from ischaemic heart disease in women was also higher in North Karelia (28%) than in Kaunas (13%).

CONCLUSIONS

Despite the remarkable decline in the occurrence of ischaemic heart disease, it still remains the most important cause of premature mortality in North Karelia. In Kaunas ischaemic heart disease mortality and attack rate increased in men. Experiences from successful cardiovascular disease prevention programmes in western countries, such as the North Karelia Project, should be exploited to prevent an increasing epidemic of ischaemic heart disease in eastern Europe.

XbaI polymorphism of the apolipoprotein B gene influences plasma lipid response to diet intervention

Fresh blood samples were collected from 103 North Karelians who had in 1981-84 participated in dietary intervention studies and analysis of the XbaI restriction fragment length polymorphism (RFLP) of apolipoprotein B (apoB) was carried out. Reanalysis of the original plasma lipid and apolipoprotein data indicated that while baseline concentrations did not differ significantly between genotypes, the response to a low-fat, low-cholesterol diet was influenced by apoB XbaI genotype: reductions in total and low density lipoprotein (LDL) cholesterol, apoB and high density lipoprotein (HDL) cholesterol were greater in subjects homo- or heterozygous for the presence of the XbaI cutting site (X1X2 or X2X2 genotype, designated X2+) as compared to those lacking the cutting site (X1X1 genotype, designated X2-). The corresponding average reductions induced by dietary intervention in X2+ and X2- subjects were: for total cholesterol 1.30 and 0.99 mmol/l (p = 0.036), for LDL cholesterol 1.04 and 0.78 mmol/l (p = 0.049), for apoB 18.3 and 8.1 mg/100 ml (p = 0.012) and for HDL cholesterol 0.26 and 0.17 mmol/l (p = 0.008).

Regional variations in cardiovascular mortality in Sweden--structural vulnerability in the local community

The aim of this investigation was to study the connection between various phenomena in the local community and the number of deaths from ischemic heart disease (IHD) for both men and women in the 45-64 age group in the period 1979-1983. The result reveals considerable regional variation. Those areas with an above average male IHD mortality also tended to differ from the norm as regards labour market, and socioeconomic conditions. There was a tendency for unemployment to be higher, the level of employment to be lower, and the number of households with no or only one person gainfully employed larger; there also tended to be more people who had taken or been forced into early retirement, average incomes tended to be lower and there was an above average proportion of blue-collar workers and a below average proportion of white-collar workers. Furthermore, there proved to be a larger proportion of older men. The factors which did not seem to be related to the number of IHD deaths were the divorce rate in the community and the degree of population density. As regards women, there was a less marked connection between the various regional phenomena and the number of IHD deaths. The mortality rate proved to be related to only two factors: the level of unemployment in the community and the proportion of high-income earners. There was a tendency, albeit weak, that areas with an above average mortality also had an above average rate of unemployment and a lower than average proportion of high-income earners.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenomatous polyps and atherosclerosis: an autopsy study of Japanese men in Hawaii

It is generally accepted that most colorectal cancers arise from adenomatous polyps and most coronary heart disease is caused by severe atherosclerosis. In order to compare the frequency of these disease precursors in men of Japanese ancestry in Hawaii, the degree of atherosclerosis of the aorta and coronary arteries was estimated by the panel method in 288 male autopsy subjects. The extent of atherosclerosis was then compared in men who did or did not have adenomatous polyps as determined at autopsy. The degree of atherosclerosis of the coronary arteries and aorta was positively and significantly related not only to the presence of adenomatous polyps, but to their size, multiplicity, and degree of atypia as well. This study suggests that shared environmental events could account for the development of severe atherosclerosis and adenomatous polyps. At the same time, it has been observed that hawaii Japanese men experience colon and rectal cancer rates higher than those of US Whites, but their coronary heart disease (CHD) rates are intermediate between the low rates of Japan and the high rates of the US white population. These differences in disease trends and differences in the serum cholesterol and fat intake of Hawaii Japanese men with CHD and colon cancer have suggested that men with these diseases represent different subsets of the westernized Japanese population. If CHD and colon cancer occur in different subsets of this population, they must stem from the accumulation of other risk factors superimposed upon the initiators of their precursor lesions.

Dietary fat and blood pressure: an intervention study on the effects of a low-fat diet with two levels of polyunsaturated fat

The role of dietary fat in human blood pressure control was studied among 84 middle-aged subjects (mainly couples) in two semirural communities in North Karelia, Finland. The families were randomly allocated into two groups that, after a baseline period of 2 weeks, changed their diet for a 12-week intervention period so that the proportion of energy derived from fats was similarly reduced in both groups, from 38 to 24%, but the polyunsaturated/saturated fatty acid (P/S) ratio was increased--from 0.2 to 0.9 in group I and to 0.4 in group II. After the intervention period, both groups switched back to their usual diet for a period of 5 weeks. During the intervention period, total serum cholesterol was reduced by 16% in group I and 14% in group II. Mean body weight and urinary sodium, potassium, calcium, and magnesium excretion changes were small or nonexistent. Mean systolic blood pressure decreased 4 mm Hg in group I (P less than 0.01) and 3 mm Hg in group II (P less than 0.01), and mean diastolic blood pressure decreased 5 mm Hg (P less than 0.001) and 4 mm Hg (P less than 0.01), respectively. The reductions were reversed during the switch-back period (P less than 0.01). These results confirm previous findings of the blood-pressure-reducing effect of a low-fat/high-P/S diet. Although a number of possible confounding factors can be ruled out, the dietary constituent accounting for the blood pressure change cannot be ascertained definitely. The results showed no significant further blood pressure reduction with more than a moderately increased P/S ratio when the saturated fat intake was markedly reduced.

Change in risk factors for coronary heart disease during 10 years of a community intervention programme (North Karelia project)

A comprehensive community based programme to control cardiovascular diseases was started in North Karelia, Finland, in 1972. Reductions in smoking, serum cholesterol concentrations, and blood pressure were among the central intermediate objectives. The effect of the programme during the 10 year period 1972-82 was evaluated by examining independent random population samples at the outset (1972) and five (1977) and 10 (1982) years later both in the programme and in a matched reference area. Over 10 000 subjects were studied in 1972 and 1977 (participation rate about 90%) and roughly 8000 subjects in 1982 (participation rate about 80%). Analyses were conducted of the estimated effect of the programme on the risk factor population means by comparing the baseline and five year and 10 year follow up results in the age range 30-59 years. The effect of the programme (net reduction in North Karelia) at 10 years among the middle aged male population was estimated to be a 28% reduction in smoking (p less than 0.001), a 3% reduction in mean serum cholesterol concentration (p less than 0.001), a 3% fall in mean systolic blood pressure (p less than 0.001), and a 1% fall in mean diastolic blood pressure (p less than 0.05). Among the female population the reductions were respectively, 14% (NS), 1% (NS), 5% (p less than 0.001), and 2% (p less than 0.05). During the first five years of the project (1972-7) the programme effectively reduced the population mean values of the major coronary risk factors. At 10 years the effects had persisted for serum cholesterol concentrations and blood pressure and were increased for smoking.

Assessing the cost-effectiveness of prevention

In an era of limited resources, cost-effectiveness analysis and cost-benefit analysis (CEA/CBA) can be significant policy-making aids. Because the often stated belief that prevention is cost-effective has not been systematically examined, we surveyed about 250 CEA/CBA articles concerning prevention. We found that few authors have followed generally accepted methodological standards, which raised questions concerning the validity of their findings and conclusions. In addition, prevention itself is a problem in CEA/CBA because of such factors as the long intervals between interventions and outcomes, problems which have rarely been considered in the CEA/CBA prevention literature. At the same time, a number of high quality studies concerning prevention indicates that United States policy makers have not aggressively pursued significant opportunities to improve health through prevention, for example by immunizing the elderly and by screening for and treating hypertension. We recommend that analysts follow general methodological principles in CEA/CBA prevention studies to assure both valid and credible results.

Evaluating community-based preventive cardiovascular programs: problems and experiences from the North Karelia project

Among the different approaches to the study of cardiovascular disease prevention are community-based programs. This type of program concerns a whole community and the intervention takes advantage of the existing service structure and community organization. The evaluation assesses the feasibility, effects on risk factor and disease reduction, costs, process, and other consequences associated with the program. Several such programs have recently been launched in the United States and some other countries. The first major community-based control program was the North Karelia project in Finland, started in 1972 and recently evaluated for its first five-year period. This paper discusses the problems in evaluating community-based CVD control programs on the experiences obtained in the North Karelia project.

Effect of diet on serum lipoproteins in a population with a high risk of coronary heart disease

The population of North Karelia, a county in Finland, has a high rate of coronary heart disease. It also has a high prevalence of hypercholesterolemia, but whether this reflects a diet rich in animal fats or is a result of genetic factors is unclear. We studied the effect on serum lipoproteins of a low-fat diet with a high ratio of polyunsaturated to saturated fatty acids in 54 middle-aged volunteers in North Karelia. Total serum cholesterol decreased, from 263 +/- 8 mg per deciliter (mean +/- S.E.) to 201 +/- 5 mg in men (P less than 0.0001) and from 239 +/- 8 to 188 +/- 8 mg in women (P less than 0.0001), along with low-density-lipoprotein cholesterol and apoprotein B. High-density lipoprotein decreased from 54 +/- 2 mg per deciliter to 44 +/- 2 in men (P less than 0.0001) and from 56 +/- 3 to 47 +/- 2 mg in women (P less than 0.0001). A small but significant reduction occurred in serum apoprotein A-I, whereas apoprotein A-II increased slightly. The individual changes in low-density-lipoprotein cholesterol correlated with those in high-density-lipoprotein cholesterol. The changes in serum lipids and apoproteins were reversed when the participants returned to their original diets. Our results suggest that the hypercholesterolemia characteristic of this population is due at least in part to dietary factors.

Sodium and potassium excretion in a sample of normotensive and hypertensive persons in eastern Finland

A 24-hour urine collection was carried out during a cardiovascular survey in eastern Finland. The study population comprised 148 hypertensive subjects in a random sample of the middle-aged population and 86 normotensive controls. The mean sodium excretion was 197 mmol/24h in both normotensive and hypertensive men, 179 mmol/24h in normotensive women, and 174 mmol/24h in hypertensive women. There were no significant differences in potassium excretion rate or in sodium: potassium molar ratio between the normotensive and the hypertensive among either men or women. There was no statistically significant correlation between blood pressure level and sodium or potassium excretion or sodium: potassium molar ratio. One in four of the subjects reported that they usually added salt to their food before tasting it. The results of this study show that the average level of salt intake in a Finnish population is high, and so is the sodium: potassium molar ratio. Although there was no correlation between sodium excretion and blood pressure levels, it is known that in this population the average blood pressure level is high and cardiovascular disease extremely frequent.

Stopping smoking and long-term mortality after acute myocardial infarction

A prospective follow-up study was carried out to investigate the relation between smoking and risk of death after an acute myocardial infarction. The study consisted of male patients under the age of 65 years, who had had an acute myocardial infarction between 1972 and 1975 in North Karelia, Finland. Of these patients, 888 survived the first six months after the acute infarction and were followed-up for three years after the infarction with regard to their deaths. The cumulative all-causes mortality rate of the patients who were still smoking six months after the acute myocardial infarction was 1.7 times that of the patients who had stopped smoking within the first six months. There was a dose-response relation between the number of cigarettes smoked daily and the mortality. The impact of smoking was greatest in the subgroups of patients with an otherwise good prognosis. We estimated that 28 per cent of the deaths in the whole group of initial smokers was attributable to continuing smoking after the infarction. On the basis of these findings we suggest that the anti-smoking advice should be an important part of the modern comprehensive care of patients with an acute myocardial infarction.

Management of hypertension and changes in blood pressure level in patients included in the hypertension register of the North Karelia Project

A major subprogramme of the North Karelia Project has been the hypertension programme which aimed at lowering the high blood pressure levels prevalent among the whole population of the province of North Karelia, and especially among middle-aged men. A community-based hypertension register, which served as the major tool of the programme, was established to keep patients under treatment and to gather information about the progress of the programme. The registration of the hypertension subjects was continued from 1972 to 1977; the registered patients had annual follow-up examinations. After 5 years of the programme, there were approximately 17 000 registered patients, which was 9.7% of the total population. The proportion of drop-outs at the annual follow-up examinations was 10-20%. 83% of the registered hypertensive subjects were undergoing drug treatment after 3 years' intervention. The percentage of normotensive subjects increased significantly year by year.

The role of lay workers in community health education: experiences of the North Karelia project

The role of natural community leaders in serving as lay health workers in a comprehensive community health programme has been explored. In rural Finland, nearly 300 persons were trained to detect cardiovascular risk factors (smoking, high-cholesterol diet, high blood pressure) in their communities, and to advise community members of the desirability of lowering these risk factors. Initial data from studies of the lay health workers and their intervention work support the concept that carefully select community health workers who are to varying degrees representative of their local populations, can well act as intermediaries in preventive health care strategies.

Hypertension control in North Karelia before the intervention of the North Karelia Project

The baseline survey of the North Karelia Project was carried out to measure the level of cardiovascular risk factors in the target population. These data on the prevalence, detection and treatment of hypertension obtained in the survey were utilized in planning the main programme. The survey was carried out in 1972 and 4275 persons aged from 25 to 59 (6.5% random sample) were examined. The prevalence of hypertension was high--21% of women and 15% of men were judged as being in need of treatment for hypertension. The blood pressure level of men was higher than that of women below 45 years of age, but in all age groups women were more often undergoing treatment. Although majority of people had had their blood pressure checked recently, only half of those who were aware of hypertension had ever been under treatment, and at the time of examination only 13% of those men and 10% of those women had restored normotension. Only one-fifth and one-third of the women who had used drugs had been under treatment for more than 5 years. Thus, the need to provide a systematic hypertension control scheme in North Karelia was urgent, as described in many other communities in the developed world. The main reason for this lies in the inability of the health care system which has not been able to maintain patients on long-term follow-up and treatment.