Anthropometric and lipid parameters trends in school children: one decade of YUSAD Study.

INTRODUCTION: Athersclerosis is a multifactorial disease that begins in childhood. There are few reports regarding influence of risk factors on the atherosclerotic processes in early period of life and adolescence. OBJECTIVE: The aim of this study was to present and analyze risk factor trends in school children over a 10-year period that were included and followed-up by the Yugoslav Study of Atherosclerosis Precursors in School Children (YUSAD Study). METHODS: There were three examinations of selected population from 13 centres. The first examination was performed when children were 10 years of age (first group; N = 6381 participants), the second examination on the same population when they were 15 years of age (second group; N = 5017) and third when children were 19/20 years of age (third group; N = 1293). Evaluated parameters included: BMI, waist circumference (WaC) and lipid profile (total cholesterol, HDL cholesterol, LDL cholesterol and triglyceride). RESULTS: A significant elevation of values (p < 0.001) of BMI, WaC and triglycerides and a significant decline (p < 0.001) of total cholesterol and LDL cholesterol in boys over 5 and 10-year period was noticed. There was a significant elevation (p < 0.001) of BMI, WaC and HDL values and a significant decline in LDL cholesterol values in girls over the 5 and 10-year period. CONCLUSION: Our results point out that girls between 10 and 19/20 years have a better lipid profile during growth. It should be stressed out that childhood and adolescence can be more beneficial in the observation of risk factor influences on pathological, genetic and clinical levels.

Determinants of 40-year all-cause mortality in the European cohorts of the Seven Countries Study.

If a few risk factors had predictive power for all-cause mortality in different geographical-cultural areas, then preventive efforts might be concentrated on these. Thirteen potential risk factors were measured in 6,554 men aged 40-59 around 1960 in Northern, Southern and Eastern European areas of the Seven Countries Study. In 40 years 85.3% of men died in the pooled areas (87.9, 81.8 and 87.9% in Northern, Southern and Eastern Europe, respectively). Six risk factors were significant predictors of events in all three areas: directly for age, smoking habits, mean blood pressure, heart rate and ECG abnormalities; inversely for forced expiratory volume. In a pooled model also father and mother life status, socio-economic status, and arm circumference (the last one in an inverse way) had significant coefficients that were not heterogeneous across areas (except for socio-economic status). Serum cholesterol was around significance. ROC curves had values of 0.833, 0.806 and 0.819 respectively in Northern, Southern and Eastern Europe, and 0.827 in the pooled areas. Correlation coefficients between observed and expected cases in deciles of estimated risk were between 0.98 and 0.99. Survivors after 40 years in the lower half of the estimated risk were 10.7, 23.6 and 13.3% in Northern, Southern and Eastern Europe, respectively. Under- or over-estimate of cross-applying risk functions did not exceed 15%. All-cause mortality and survival in middle aged men during 40 years were strongly associated with a few, mainly cardiovascular, risk factors, whose predictive power was similar in different cultures across Europe.

Physical activity evaluation in Yugoslav Study of the Precursors of Atherosclerosis in School Children - YUSAD study.

INTRODUCTION: It is observed that there is a lack of physical activity and exercise in children, stressing higher prevalence of childhood obesity. The purpose of the study was to evaluate duration of physical activity in a child population and correlation of dynamics in physical activity during 5 years of follow-up in the same population. MATERIAL AND METHODS: We evaluated 3243 school children from 12 regional centres across Serbia. The first examination was done when the children were 10 years old (baseline group), while the second examination was done on the same population when children were 15 years old. Physical activity was classified as recreational activity after school. We analysed 3 groups regarding physical activity: a group of children who were physically active less than 1 hour per day (group I), a second group active from 1 hour to < 3 hours per day (group II), and a third group active ≥ 3 hours per day (group III). RESULTS: In our study we have found on examination that the majority of children were physically active between 1 and 3 hours per day. Our results indicate that there is significant movement from groups I and III toward group II on the second examination regarding the proportion in the baseline group. There is a significant increase in the number of children in group I as they get older. CONCLUSIONS: School children in Serbia are physically active predominantly between 1 and 3 hours per day at the age between 10 and 15 years.

Homogeneity in the relationship of serum cholesterol to coronary deaths across different cultures: 40-year follow-up of the Seven Countries Study.

BACKGROUND: The aim was to investigate whether multivariate coefficients of serum cholesterol in the prediction of coronary heart disease (CHD) deaths were similar across different cultures in a long-term follow-up. DESIGN: Thirteen cohorts for a total of 10,157 men aged 40-59 years at entry, enrolled in seven countries (USA, Finland, the Netherlands, Italy, Serbia, Greece, Japan) were repeatedly examined and followed up for 40 years. METHODS: Serum cholesterol measured at baseline, and then on repeated occasions, was studied, using multivariate models, in relation with the occurrence of CHD deaths during a 40-year follow-up. RESULTS: Homogeneity of multivariate serum cholesterol coefficients was found considering cholesterol levels at baseline, as average of up to three measurements during the first 10 years, as average of up to six measurements in 35 years, using the time-dependent technique with up to three measurements in 10 years, and with up to six measurement in 35 years. CONCLUSION: The strength of the association between serum cholesterol and CHD death seems homogeneous across different cultures characterized by different levels of serum cholesterol and different absolute risk of CHD death.

Forty-year coronary mortality trends and changes in major risk factors in the first 10 years of follow-up in the seven countries study.

Time trends in coronary heart disease (CHD) mortality during a 40-year follow-up were studied in the Seven Countries Study. Thirteen cohorts of men aged 40-59 at entry were enrolled in seven countries (USA, Finland, the Netherlands, Italy, Serbia, Greece and Japan) for a total of 10,628 subjects. Cardiovascular risk factors were measured at entry and at the 10-year follow-up examination and coronary heart disease mortality data collected during 40 years. During the 40-year follow-up, the hazard rate of the Weibull parametric distribution (annual conditional risk of death) for CHD mortality tended to slightly decline in the US, Finnish, Dutch and Japanese cohorts, moderately increased in Italy and exponentially increased in cohorts of Serbia and Greece. A strong positive association was found between the shape of the hazard curve, describing the acceleration of the hazard, and a score of population mean risk factor changes (serum cholesterol, systolic blood pressure and smoking prevalence) observed during the first 10 years of follow-up, with a correlation coefficient of 0.91 between the two indicators. The countries with a relative decline in the annual hazard function were the same where, during the same historical period, large decreases in official death rate from CHD were recorded, and viceversa. The acceleration in mortality risk for CHD mortality in different countries, described by the shape of the Weibull distribution, is related to changes in mean levels of major coronary risk factors.

Effects of past and recent blood pressure and cholesterol level on coronary heart disease and stroke mortality, accounting for measurement error.

The authors aimed to quantify the effects of current systolic blood pressure (SBP) and serum total cholesterol on the risk of mortality in comparison with SBP or serum cholesterol 25 years previously, taking measurement error into account. The authors reanalyzed 35-year follow-up data on mortality due to coronary heart disease and stroke among subjects aged 65 years or more from nine cohorts of the Seven Countries Study. The two-step method of Tsiatis et al. (J Am Stat Assoc 1995;90:27-37) was used to adjust for regression dilution bias, and results were compared with those obtained using more commonly applied methods of adjustment for regression dilution bias. It was found that the commonly used univariate adjustment for regression dilution bias overestimates the effects of both SBP and cholesterol compared with multivariate methods. Also, the two-step method makes better use of the information available, resulting in smaller confidence intervals. Results comparing recent and past exposure indicated that past SBP is more important than recent SBP in terms of its effect on coronary heart disease mortality, while both recent and past values seem to be important for effects of cholesterol on coronary heart disease mortality and effects of SBP on stroke mortality. Associations between serum cholesterol concentration and risk of stroke mortality are weak.

The relationship of age, blood pressure, serum cholesterol and smoking habits with the risk of typical and atypical coronary heart disease death in the European cohorts of the Seven Countries Study.

OBJECTIVE: To explore whether "typical" coronary heart disease (CHD) such as fatal myocardial infarction and sudden death relate to major cardiovascular risk factors in the same way as the "atypical" CHD, such as fatal heart failure and chronic arrhythmias. DESIGN AND SETTING: Ten cohorts (6633 cardiovascular disease-free men, aged 40-59) in five European countries were examined, age and three major risk factors were measured (systolic blood pressure, serum cholesterol, and smoking habits) and 35-year mortality data were collected. Proportional hazard models were solved with typical and atypical CHD deaths treated separately. RESULTS: Death rates from typical and atypical CHD were inversely related among the five countries. Mean age at death was significantly higher for atypical than typical (75.8 versus 71.6 years; p < 0.001). In the multivariate analysis conducted on pools of 5 countries (adjusted for countries), the relationship of risk factors with typical CHD was direct and significant for age (hazard ratio-HR-for 5 years of age 1.44 (95% CI 1.36-1.52)), systolic blood pressure (HR for 20 mm Hg, 1.39 (95% CI 1.32-1.47)), serum cholesterol (HR for 1 mmol/l of 1.22 (95% CI 1.16-1.27)) and smoking habits (HR smokers versus non-smokers of 1.39 (95% CI 1.24-1.57)). For atypical CHD, age had a larger HR of 2.27 (95% CI 2.05-2.52), systolic blood pressure had a smaller HR of 1.28 (95% CI 1.16-1.41), serum cholesterol had an inverse non-significant HR of 0.90 (0.58-1.58) and smoking habits had a larger HR of 1.54 (95% CI 1.26-1.89). CONCLUSIONS: Age and serum cholesterol were differently related with typical and atypical CHD deaths, suggesting different etiologies for these coronary diseases.

Cardiovascular risk factors and blood pressure in a primary care unit: Yugoslav Study of the Precursors of Atherosclerosis in School Children (YUSAD).

OBJECTIVES: The presence of cardiovascular risk factors in children may be important in the development of atherosclerosis in adulthood. Adequate control of blood pressure is a cornerstone in atherosclerosis prevention. The aim of the Yugoslav Study of the Precursors of Atherosclerosis in School Children (YUSAD) was to identify risk factors for elevated blood pressure in school children. METHODS: The YUSAD study is a multicentre follow-up study comprised of two cross-sectional surveys conducted five years apart. At baseline, 10-year-old children (3226 boys and 3074 girls [n=6300]) were randomly selected during periodical visits to primary health care centres. The risk factors measured were heart rate, weight, body mass index (BMI), waist-to-hip ratio, grade point average and current smoking status. RESULTS: Significant age and sex differences were identified in systolic blood pressure, diastolic blood pressure and all investigated independent variables. In a multivariate analysis, diastolic blood pressure in 10-year-old boys was directly and significantly related to total cholesterol and height, whereas it was inversely related to weight. At follow-up, in the multivariate model, only BMI was a significant predictor of diastolic blood pressure in boys. In girls at baseline in the multivariate regression analysis, the only significant predictor of diastolic blood pressure was total cholesterol. In 15-year-old girls, diastolic blood pressure was significantly and directly related to BMI and heart rate, whereas it was inversely related to weight. For both 10- and 15-year-old male and female participants, none of the variables by multivariate analysis were a significant predictor of systolic blood pressure. CONCLUSIONS: Age, sex, heart rate, cholesterol and weight are the most important predictors of blood pressure in school children.

Long-term trends in major cardiovascular risk factors in cohorts of aging men in the European cohorts of the Seven Countries Study.

BACKGROUND AND AIMS: Time trends in major cardiovascular risk factors are described in cohorts of middle-aged men followed for 35 years in 9 European cohorts of Finland, The Netherlands, Italy, Serbia and Greece. METHODS: Men aged 40 to 59 years at entry in the early 1960s were repeatedly re-examined 3 to 5 times over the last 35 years. Systolic blood pressure, serum cholesterol, body weight and body mass index were considered for analysis, including study of aging (35 years of follow-up) and of generation effects (10 years for men aged 50-59 in the period 1960-1970 and separately 10 years for men aged 75-84 years in the period 1985-1995). RESULTS: For the aging effect, average systolic blood pressure increased approximately 15 mmHg over 25 years maintaining a steady state thereafter, the largest increases being found in Serbia and Greece. Average serum cholesterol varied between approximately 4.5 in Serbia and 6.5 mmo/L in Finland in about 1960. Twenty-five years later, the average level was about 6 mmol/L in all five countries and decreased slightly thereafter. Average body weight and body mass index increased in all countries for 25 years and levelled off thereafter. For the generation effect, average systolic blood pressure decreased in all countries, with the exception of men aged 50-59 in Serbia and men aged 75-84 in The Netherlands. Average serum cholesterol uniformly increased in men aged 50-59 for the younger age-class and slightly decreased in men aged 75-84. Average body weight and body mass index increased systematically in all countries and in both age groups. CONCLUSIONS: Major changes were the great increases in average systolic blood pressure and serum cholesterol level in Serbia and in systolic blood pressure level in Greece between 1960 and 1985, and the large decrease in average serum cholesterol in Finland between 1970 and 1995. Average body weight and body mass index showed universal increases in both middle-aged and older men after 1960.

The relation between pulse pressure and cardiovascular mortality in 12,763 middle-aged men from various parts of the world: a 25-year follow-up of the seven countries study.

BACKGROUND: Hypertension is a dominant characteristic in the prediction of cardiovascular diseases (CVDs). We aimed to evaluate the association of blood pressure measurements with CVD mortality among different populations of the world. METHODS: A total of 12 763 men, aged 40 to 59 years, from 7 countries (United States, Japan, Italy, Greece, former Yugoslavia, Finland, and the Netherlands) were surveyed from 1958 to 1964. Follow-up for vital status and causes of death was carried out over 25 years. RESULTS: All baseline blood pressure measurements were the best predictors of CVD mortality, compared with age, physical activity, total serum cholesterol level, body mass index or height, and smoking. Moreover, pulse pressure and diastolic and systolic blood pressures were the best predictors for CVD death, followed by mean and mid blood pressures. The age-adjusted hazard ratio per 10-mm Hg increase in pulse pressure varied among cohorts from 1.19 in the United States (P = .04) to 1.29 in southern Europe (P = .01). Differences among cohorts were not significant. In the pooled cohorts, pulse pressure measurements were also a significant predictor for coronary heart disease (hazard ratio per 10-mm Hg increase, 1.15; P = .04) as well as stroke death (hazard ratio per 10-mm Hg increase, 1.32; P = .01). CONCLUSIONS: Pulse pressure followed by diastolic and systolic blood pressures were the best predictors for CVD mortality among other blood pressures, as well as age, physical activity, total serum cholesterol level, anthropometric indexes, and smoking habits. No significant differences were observed among the different populations studied.

Short and long term association of a single serum cholesterol measurement in middle-aged men in prediction of fatal coronary and other cardiovascular events: a cross-cultural comparison through Europe.

AIMS: The purpose was to study the association of a single serum cholesterol measurement with early and late coronary and other cardiovascular deaths during 35 years of follow-up in samples of men aged 40-59 years in five European countries. METHODS AND RESULTS: A single serum total cholesterol measurement was considered in samples from Finland (N = 1563), the Netherlands (N = 811), Italy (N = 1642), Serbia (N = 1537) and Greece (N = 1158) (total = 6711). Seven partitioned proportional hazards models were solved, one for each of seven independent 5-year blocks, to predict coronary, stroke, cardiovascular disease and all-cause mortality risk. Partitioned hazard scores were cumulated. The resulting curves showed a relatively constant strength in risk for coronary deaths as a function of baseline serum cholesterol levels, although a strong relationship during the first 10-year period was followed by a weaker relationship later on. The pooled estimates for the five countries gave a relative risk for 1 mmol/l of serum cholesterol (95% confidence intervals) of 1.44 (1.23-1.68) for the first period; 1.52 (1.31-1.76) for the second period; and 1.16 (1.02-1.32) for the third period; 1.18 (1.05-1.32) for the forth period; 1.17 (1.05-1.31) for the fifth period; 1.22 (1.10-1.35) for the sixth period; 1.18 (1.05-1.32) for the seventh 5-year period of follow-up. No significant relationship were found between serum cholesterol and stroke and all-cause mortality, while intermediate findings were obtained for cardiovascular diseases. CONCLUSION: A single serum cholesterol measurement in middle aged-men maintains a strong relationship with the occurrence of coronary heart disease (CHD) deaths during 35 years of follow-up.

Cardiovascular drug use and differences in the incidence of cardiovascular mortality in elderly Serbian men.

OBJECTIVE: To assess whether the difference in risk of cardiovascular mortality between urban and rural areas of Serbia could be explained by differences in the use of cardiovascular medication. METHODS: The Serbian cohorts of the Seven Countries Study, Velika Krsna (VK), Zrenjanin (ZR) and Belgrade (BG), were enrolled in 1962-1964 and were followed up for 25 years. The survivors of these cohorts were re-examined in 1987, 1988 and 1989, respectively. This second examination of elderly men aged 65 to 84 years included a questionnaire about current use of cardiovascular medication, risk factors and diseases and a physical examination. All subjects were followed until death or the predefined censor date (10 years after baseline). The Cox proportional hazards model was used to calculate the risk of cardiovascular mortality in the rural cohorts compared to the urban cohort and to adjust for confounding. MAIN OUTCOME MEASURE: Cardiovascular death. RESULTS: A total of 227 men from VK, 184 men from ZR and 287 men from BG were followed for a mean duration of 7.4 years and was complete for all subjects. After exclusion of 13 subjects with missing medication data, the incidences of cardiovascular mortality in VK, ZR, and BG were 60, 74, and 26 per 1,000 person-years, respectively. The prevalence of cardiovascular medication use was 38% in VK, 52% in ZR, and 59% in BG. The greatest difference in use of specific medication was observed for betablockers (0% in VK and ZR, 13% in BG). After adjustment for cardiovascular risk factors, diseases and age, the relative risks (RRs) of cardiovascular mortality were 2.12 [95% CI: 1.44-3.12], and 2.27 [95% CI: 1.56-3.30] in VK, and ZR compared to BG. Additional adjustment for the use of cardiovascular medication increased these RRs to 2.40 [95% CI: 1.61-3.60] and 2.55 [95% CI: 1.72-3.78], respectively. CONCLUSION: The variation in cardiovascular medication use could not explain the excess risk of mortality in the rural Serbian cohorts compared to urban Belgrade.

The role of a baseline casual blood pressure measurement and of blood pressure changes in middle age in prediction of cardiovascular and all-cause mortality occurring late in life: a cross-cultural comparison among the European cohorts of the Seven Countries Study.

OBJECTIVE: The first objective was to study the long-term association of a casual measurement of systolic blood pressure (SBP) with cardiovascular deaths (CVD) and all causes of death (ALL) occurring during 35 years of follow-up in different population samples of men aged 40-59 years in five European countries. The second objective was to study the predictive power of early change in SBP levels (years 0-10) in relation to late fatal events (years 10-35). DESIGN, SETTING AND PARTICIPANTS: A single measurement of SBP was considered in cohorts in Finland, The Netherlands, Italy, Serbia and Greece for a total of 6507 men. Three partitioned proportional hazards models were solved, one for each independent and subsequent time block of 10 years, after excluding data from the first 5 years, to predict the risk of cardiovascular disease deaths of atherosclerotic origin (CVD) and all cause mortality (ALL). Independently, the predictive power of SBP changes (Delta-SBP) occurred during the first 10 years of follow-up was explored as a possible additional risk factor in relation to CVD and ALL deaths occurring between year 10 and year 35 of follow-up. RESULTS: Partitioned hazard scores derived from the three partitioned functions were cumulated. The resulting curves showed a continuous and significant association of baseline SBP with CVD and ALL deaths during three decades, although the strength of association declined significantly from the first to the third decade. The relative risk for 20 mmHg of SBP (and its 95% confidence intervals) in predicting CVD deaths was 1.65 (1.54-1.77) for the first 10-year block; 1.33 (1.24-1.42) for the second block; and 1.22 (1.13-1.31) for the last 10-year block. The corresponding levels of ALL deaths were 1.41 (1.34-1.49), 1.26 (1.19-1.32) and 1.11 (1.05-1.17). Changes in SBP during 10 years (Delta-SBP) added predictive power to baseline measurements in a direct and significant way, with a relative risk for a change of 10 mmHg of 1.14 (1.10-1.17) for CVD deaths and 1.11 (1.09-1.13) for ALL deaths. CONCLUSION: A single measurement of systolic blood pressure in middle-aged men maintains a strong relationship with fatal CVD and ALL deaths during the next 35 years, although for late events the strength of the association definitely declines. Changes in systolic blood pressure levels during the first 10 years of follow-up add predictive power, while baseline measurements retain their predictive power.