Relationship of some risk factors with typical and atypical manifestations of coronary heart disease.

BACKGROUND: This analysis explores whether 'typical' clinical manifestations of coronary heart disease (CHD) such as myocardial infarction and sudden death, relate to major cardiovascular risk factors in the same way as the 'atypical' manifestations, e.g. heart failure and chronic arrhythmias. PATIENTS AND METHODS: Sixteen cohorts of men aged 40-59 in seven countries were examined, risk factors measured (age, systolic blood pressure, serum cholesterol and smoking habits) and 25-year mortality data collected in a systematic way. Cohorts were located in the US (n = 1), Finland (n = 2), the Netherlands (n = 1), Italy (n = 3), former Yugoslavia (n = 5), Greece (n = 2) and Japan (n = 2), with a total of 12,763 individuals. Ecological analysis based on regression equations and correlation among cohorts, and individual analyses based on proportional hazard models in pools of cohorts were conducted with typical and atypical CHD deaths as dependent variables. RESULTS: The ecological analysis suggests a significant relationship of populational mean levels of serum cholesterol and of systolic blood pressure to age-adjusted death rates from typical CHD manifestations. The relationships for atypical CHD deaths were not statistically significant. In the ecological approach with multivariate analysis, none of the risk factors showed relevant associations with event rates, except serum cholesterol and typical CHD deaths. The ecological relationship of serum cholesterol to atypical CHD death rates was negative but not significant. On average, mean age at death was statistically higher among atypical CHD than typical CHD patients (70.2 vs. 65.8 years). In the individual multivariate analysis conducted on pools of countries, the relationship of risk factors with typical CHD deaths was direct and significant for age, systolic blood pressure, and smoking habits in Northern Europe and America and Southern Europe, but only for systolic blood pressure and smoking habits in Japan, whereas for atypical CHD, the predictive factors were age, systolic blood pressure and cigarette smoking in Northern Europe and America and Southern Europe, but only age in Japan. CONCLUSIONS: The usual relationship of blood pressure and smoking habits and the differential relationship of serum cholesterol with atypical CHD (negative or absent) versus typical CHD (direct and significant) could be explained by 'two different diseases' or by a mix of poorly classified conditions among the atypical cases.

The relation of chronic diseases to all-cause mortality risk--the Seven Countries Study.

The relation of chronic conditions on all-cause mortality in population samples was studied based on observations from the Seven Countries Study. The objective of this work was to study the risk of death during a 15-year follow-up of middle-aged men in relation to six chronic diseases. Fifteen cohorts of men aged 50-69, totalling 8122 subjects, were examined around 1970 in seven countries: Finland, The Netherlands, Italy, Croatia (former Yugoslavia), Serbia (former Yugoslavia), Greece and Japan. Clinical diagnoses findings were made for coronary heart disease (CHD), 'other heart diseases' (OTH), peripheral arterial disease (PAD), stroke (STR), chronic obstructive pulmonary disease (COPD), and diabetes mellitus (DIAB). All-cause mortality was assessed in the subsequent 15 years. Death rates and relative risks were estimated from crude data, and in proportional hazards models after adjustment for age, systolic blood pressure and serum cholesterol level, cigarette smoking and body mass index. Large regional differences were found in the prevalence of the six conditions. Weak relations were found between population prevalence of each disease and population death rates for that disease. Among cohorts the relative risk of death in 15 years from any cause, adjusted for other risk factors, showed little variation among countries. Pooled relative risks, adjusted by the inverse of variance (with 95% CI) were: for CHD, 1.81 (1.60-2.06); for OTH, 1.47 (1.28-1.69); for PAD, 1.64 (1.39-1.93); for STR, 1.56 (1.23-1.98); for COPD, 1.67 (1.48-1.88); and for DIAB, 1.75 (1.43-2.15). The smallest variability of prognosis among countries was found for CHD, OTH and DIAB; the largest for PAD, STR and COPD. Despite simple clinical diagnostic procedures and large differences in prevalence, the relation of established prevalent conditions to subsequent all-cause mortality is relatively uniform among countries and across these conditions, with a relative risk of dying in 15 years usually ranging between 1.5 and 2.0.

Changes in population cholesterol levels and coronary heart disease deaths in seven countries.

BACKGROUND: Are trends in coronary heart disease deaths based on risk factor changes? OBJECTIVE: To study the relationship between trends in coronary deaths and changes in blood cholesterol in the Seven Countries Study. MATERIAL AND METHODS: Sixteen cohorts of men aged 40-59 years from seven countries (U.S.A., Finland, the Netherlands, Italy, Croatia (former Yugoslavia), Serbia (former Yugoslavia), Greece, Japan) were units for the analyses of serum cholesterol measured at entry and after 5 and 10 years, and for mortality over 25 years. RESULTS: In the populations, the ecological relationship of mean serum cholesterol at entry to late coronary heart disease death rates during the 10- to 25-year follow-up was weak, with an R-square of 0.31. Cholesterol measurements made at year 10, and an indicator of cholesterol change during the first 10 years, increased the association (R-square, 0.49). A negative and significant interaction was shown between baseline population cholesterol levels and their 10-year change. As an indicator of acceleration in mortality, cholesterol change over 10 years was also positively correlated (partial R-square 0.44) with the ratio of 25-year to 5-year deaths. CONCLUSIONS: In the Seven Countries Study, late coronary heart disease death rates are largely "explained' by changes in blood cholesterol levels during the early phases of the study, mainly due to increases in lower cholesterol levels among some cohorts.

Twenty-five-year prediction of stroke deaths in the seven countries study: the role of blood pressure and its changes.

BACKGROUND AND PURPOSE: This report explores the prediction of long-term stroke mortality in cohorts of the Seven Countries Study. METHODS: Sixteen cohorts of men aged 40 to 59 years at entry were examined at years 0, 5, and 10, with mortality follow-up through 25 years. RESULTS: Stroke death rates in 25 years were high in rural Serbia, Croatia, and Japan; intermediate in Italy, Greece, and urban Serbia; and low in Finland, the Netherlands, and the United States. Age and blood pressure were powerful predictors of 25-year stroke mortality in almost all cohorts and countries. Proportional hazards regression coefficients were .0232 increase in stroke death hazard per millimeter of mercury (t=14.60) for systolic blood pressure and .0409 (t=13.41) for diastolic blood pressure. Moderate blood pressure increases from low usual levels were associated with lower stroke mortality rates in years 10 to 25. Increases of blood pressure starting from high usual levels were associated with increased rates of stroke mortality. Systolic blood pressure was associated with stroke mortality at given levels of diastolic pressure, but diastolic blood pressure was not predictive of stroke mortality at given levels of systolic blood pressure. CONCLUSIONS: Associations of systolic and diastolic blood pressure with stroke mortality were similar in cultures with different stroke mortality rates. Increases in blood pressure were associated with subsequent excess stroke mortality only in those who started from high usual levels; this study finds lower stroke risk in those men whose blood pressure increased moderately from low usual levels. Diastolic blood pressure is not independently associated with stroke risk in these populations.

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.

Twenty-five year mortality from coronary heart disease and its prediction in two Croatian cohorts of middle-aged men.

Two cohorts of men aged 40-59 in geographically defined areas of Croatia, former Yugoslavia, were enrolled in 1958 and cardiovascular risk factors were measured. The cohort of Dalmatia, on the Adriatic coast, was made up of 671 men (participation rate 98%), that of Slavonia, in the inland plain, of 696 men (participation rate 91%). Similar examinations were repeated 5 and 10 years after the entry one. A complete follow-up for vital status and causes of death was run for 25 years. Death rates in 25 years from coronary heart disease (CHD) were 90 per 1000 in Dalmatia and 148 per 1000 in Slavonia where also all other major causes of death and all-cause mortality rates were higher (642 vs 465 per 1000 in 25 years). Univariate and multivariate analysis relating ten risk factors to CHD mortality, showed that age and systolic blood pressure were significant predictors in Dalmatia; age, subscapular skinfold and body mass index (inverse) in Slavonia; and age, systolic blood pressure and subscapular skinfold in a multivariate model with lumped cohorts, where dummy variables identifying cohorts indicated a large unexplained extra-risk in Slavonia. In the pooled analysis cigarette smoking and serum cholesterol carried non significant coefficients. Blood pressure change in the first 10 years of follow-up added predictivity to a model exploring the delayed CHD morality occurring between year 10 and 25 of follow-up. Among the base-line measurements only serum cholesterol was significantly different between the two groups (188 mg/dl in Dalmatia and 199 mg/dl in Slavonia).(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of propranolol, prindolol, practolol and verapamil versus placebo on exercise induced tachycardia in patients with ventricular preexcitation.

Propranolol, prindolol, practolol and verapamil have been given orally in a fixed dose to subjects with preexcitation syndrome in a cross over study. The effect on exercise induced tachycardia, prevention of tachyarrhythmias and normalization of heart rate after exercise was investigated. Propranolol, practolol and prindolol significantly (p less than 0.01-0.05) reduced the heart rate at rest and during exercise and favourably influenced the normalization of the heart rate after exercise. The effect on effort tolerance (work done till the submaximal heart rate was reached) was significantly better after propranolol (versus prindolol and verapamil) and practolol (versus verapamil) only. Verapamil showed a consistent effect only given intravenously in paroxysmal tachycardia while in the majority of patients there was no difference between oral verapamil and placebo.