K.I. Ivanov’s research while affiliated with Ministry Of Health Of The Russian Federation and other places

The purpose of this study was to investigate the impact of economic and cultural change on immune function and psychosocial stress in an indigenous Siberian population. We examined Epstein-Barr virus antibodies (EBV), an indirect biomarker of cell-mediated immune function, in venous whole blood samples collected from 143 Yakut (Sakha) herders (45 men and 98 women) in six communities using a cross-sectional study design. We modeled economic change through the analysis of lifestyle incongruity (LI), calculated as the disparity between socioeconomic status and material lifestyle, computed with two orthogonal scales: market and subsistence lifestyle. EBV antibody level was significantly negatively associated with both a market and a subsistence lifestyle, indicating higher cell-mediated immune function associated with higher material lifestyle scores. In contrast, LI was significantly positively associated with EBV antibodies indicating lower immune function, and suggesting higher psychosocial stress, among individuals with economic status in excess of material lifestyle. Individuals with lower incongruity scores (i.e., economic status at parity with material resources, or with material resources in excess of economic status) had significantly lower EBV antibodies. The findings suggest significant health impacts of changes in material well-being and shifting status and prestige markers on health during the transition to a market economy in Siberia. The findings also suggest that relative, as opposed to absolute, level of economic status or material wealth is more strongly related to stress in the Siberian context.

C-reactive protein (CRP), an acute-phase reactant and marker of inflammatory response, is known to be an important predictor of future cardiovascular mortality, independent of other risk factors. The purpose of this research was to investigate the association between CRP, adiposity, and blood pressure in the Yakut, an indigenous Siberian population undergoing rapid cultural change. We conducted a cross-sectional study of 265 healthy Yakut adults in six villages in rural northeastern Siberia. Plasma CRP was measured by high-sensitivity immunoturbidimetric assay. The median CRP value was 0.85 mg/l, with values for the 25th, 50th, and 75th percentiles of 0.30, 0.85, and 2.28 mg/l, respectively. CRP was positively associated with age (r = 0.19; P = 0.002), but not plasma lipids or smoking status. CRP was associated with measures of central adiposity and characteristics of the metabolic syndrome, particularly in women. We found significantly higher CRP across quintiles (Q) of waist circumference for women (difference = 0.7 mg/l; P = 0.035), but not men (difference = 0.36 mg/l; P = 0.515). CRP was significantly associated with systolic blood pressure in men (difference, Q1 vs. Q5 = 1.1 mg/l; P = 0.044) but not women (difference, Q1 vs. Q5 = 0.03 mg/l; P = 0.713) after adjusting for age, waist circumference, and smoking status. CRP in the Yakut was considerably lower than was reported for other populations. The low CRP levels may be explained in part by a low prevalence of abdominal obesity. Among the Yakut, the high physical-activity demands of a traditional herding lifeway likely play a role through high energy expenditure and maintenance of negative energy balance. Our findings underscore the need for further research on the metabolic activity of adipose tissue, blood pressure, and inflammatory activation in non-Western populations.

The rapid social and cultural changes introduced by the collapse of the Soviet Union have resulted in important differences in cardiovascular health for indigenous Siberians. This study investigated diet and lifestyle determinants of plasma lipids in the Yakut, an indigenous Siberian herding population. The study used a cross-sectional design with data on 201 subjects in three urbanized towns and three rural communities in northeastern Siberia. Data on sociodemographic characteristics, dietary intake, and material lifestyle were collected, and lipids were analyzed from venous whole blood. Diet was analyzed using patterns of dietary intake based on principal components analysis of a dietary intake (food frequency) questionnaire. We identified three diet patterns: a traditional subsistence diet, a market foods diet, and a mixed diet. The effect of lifestyle on cardiovascular risk factors was measured using an ethnographically defined lifestyle index, with two orthogonal dimensions: subsistence lifestyle and modern lifestyle. Total cholesterol (TC) and low-density lipoprotein (LDL) were significantly higher among those consuming a traditional subsistence diet of meat and dairy products. A modern lifestyle was associated with lower TC and LDL but higher adiposity and higher risk of obesity. LDL and TC were higher in rural communities and lower in urbanized towns. The significantly higher lipid levels associated with a subsistence diet and indirectly with a subsistence lifestyle indicate the emergence of a significant health problem associated with the social and cultural changes occurring in Yakutia today. These findings underscore the need for dietary modification and promotion of physical activity among those most at risk for cardiovascular disease (CVD). Moreover, these results differ from those commonly seen in "modernizing" populations, in that elements of subsistence lifestyle are associated with an elevated rather than reduced risk of CVD. Such variable responses to lifestyle change emphasize the need to better understand the distinct social and historical events that may influence health changes among populations in transition.

To study trends in prevalence, risk factors (RF) and mortality of ischemic heart disease (IHD), contribution of RF to risk of death due to IHD and other cardiovascular diseases (CVD) among male population of Yakutsk; to determine characteristics of atherosclerosis among native male population and migrants. A clinicopathological epidemiological trial covered male population of Yakutsk. It was performed by standard techniques within the scope of the cooperative program. The analysis of the trends for the last 10 years demonstrates a marked rise in the incidence rates of arterial hypertension (AH), overweight and hypercholesterolemia. CVD mortality reached 38.4% of overall mortality. Such factors as AH, smoking, IHD, ischemic ECG changes and overweight contribute much to the integral risk of CVD death. A comparative morphometric analysis of atherosclerosis development in 1965-1968 and 1985-1988 showed accelerated development of atherosclerosis both among native population and migrants in 1985-1988. There are population differences in development of atherosclerosis in males from native population and migrants. The effects of trace elements on formation of atherosclerosis components in the Far North were evaluated. Present-day epidemiological situation in relation to IHD and other CVD necessitates further monitoring of the situation, activation of primary and secondary IHD prevention among population of the Far North.

Prevalence of ischemic heart disease, its main risk factors, as well as their relationship were assessed in a cross-sectional epidemiological study of a random representative sample of professional car drivers aged 20-59 years. Prevalence of hypertension, smoking, hypercholesterolemia and hypo-alphacholesterolemia was found to be high. Prevalence of hypertension, excess body mass and ischemic heart disease were positively related with age. Ischemic heart disease was more frequent in the presence of hypertension, excess body weight, hypertriglyceridemia and hypo-alphacholesterolemia. High level of risk factors of ischemic heart disease morbidity and mortality among professional car drivers requires implementation of preventive measures.

Aim. To study trends in prevalence, risk factors (RF) and mortality of ischemic heart disease (IHD), contribution of RF to risk of death due to IHD and other cardiovascular diseases (CVD) among male population of Yakutsk; to determine characteristics of atherosclerosis among native male population and migrants. Material and methods. A clinicopathological epidemiological trial covered male population of Yakutsk. It was performed by standard techniques within the scope of the cooperative program. Results. The analysis of the trends for the last 10 years demonstrates a marked rise in the incidence rates of arterial hypertension (AH), overweight and hypercholesterolemia. CVD mortality reached 38.4% of overall mortality. Such factors as AH, smoking, IHD, ischemic ECG changes and overweight contribute much to the integral risk of CVD death. A comparative morphometric analysis of atherosclerosis development in 1965-1968 and 1985-1988 showed accelerated development of atherosclerosis both among native population and migrants in 1985-1988. There are population differences in development of atherosclerosis in males from native population and migrants. The effects of trace elements on formation of atherosclerosis components in the Far North were evaluated. Conclusion. Present-day epidemiological situation in relation to IHD and other CVD necessitates further monitoring of the situation, activation of primary and secondary IHD prevention among population of the Far North.

Prevalence of hypertension among men aged 20-54 years in 17 cities of different regions was related to risk factors and ischemic heart disease mortality. The latter was recorded during the period of 6 years. Overall prevalence of hypertension was 33,6% however three groups of populations were distinguished: with low (25,2%), medium (33,7%) and high (44,8%) prevalence of hypertension. Body mass, age, alcohol, smoking, and dyslipoproteinemia contributed significantly to the prevalence of hypertension. Mortality increased with elevation of blood pressure. Relative risk of death was higher in populations with high and medium compared with low prevalence of hypertension.

Cardiovascular disease (CVD) is the main reason of death among the population of Eastern Siberia (Yakutia). Monitoring of epidemiological situation of coronary heart disease (CHD) and other CVD allows to make goal-directed preventive programs in region of extreme conditions. Methods: Two casual representative cohorts of men at the ages of 20-54 years during 1985-87 and 1997-99 (n=2666 and n=831, approximately) was examined. The study was carried out according to WHO standard methods. The men formerly examined in 1985-87 were objects of follow-up observation for registration of "end points". Results: The prevalence of high blood pressure was 26.7%, obesity - 23.2 %, smoking - 43.7 %. At the analysis of the lipid spectrum of blood serum was established, that the prevalence of hypercholesterolemia, hypertriglyceridemia and hypoHDLcholesterolemia was 21.5 %, 6.8 % and 3.9 % approximately. The prevalence of CHD was 18.7 %, myocardial infarction - 2.6 %, angina - 7.1 %. Authors established the middle levels of total cholesterol (228.3 mg/dL), tryglicerides (119.1 mg/dL) and HDL cholesterol (55.8 mg/dL). During a 10-year follow-up interval 133 men have died. Age-adjusted rate of total mortality was 4.9 per 1000 person-years, including CVD mortality - 1.9 per 1000 person-years. At an estimation of mortality in quintiles of systolic blood pressure (SBP) direct relation between SBP level and total mortality incidence is detected. Curves of CHD mortality and CVD mortality by their characters reminded "J"-shaped relation. Curves of total mortality and CVD mortality in quintiles of body mass index reminded "U"-shaped relation. CHD, CVD and total mortality were associated with the status of smoking. Relative risk (RR) of CHD, CVD and total mortality sharply grew in 2-3 times at smoking up to 20 cigarettes/day (p<0.01). RR of CHD mortality was 4.7 times higher in those who smoked more than 20 cigarettes/day, then in never smokers (p<0.01). Multivariate (Cox regression model) estimation of relative risk total mortality showed, that the essential contribution to risk of death is made by such variables as raised SBP [OR 1.02, 95%CI (1.01-1.03)], smoking [OR 2.81, 95%CI (1.58-5.00)], age [OR 1.05, 95%CI (1.02-1.08)], presence of angina [OR 2.28, 95%CI (1.14-4.55)]. Conclusion: For last 10 years in Eastern Siberia the epidemiological situation of CHD has worsened. In republic Sakha (Yakutia) the concept of reorganization of public health with a priority of prevention of the basic not infectious diseases is introduced.

Random representative sample of men aged 20-54 years in Yakutsk was followed for 10 years. Data of this follow-up were used for the study of relationship between total, cardiovascular and coronary mortality and risk factors. Cardiovascular mortality in this population constituted 38,4% of total mortality. Hypertension, smoking, diagnosis of ischemic heart disease, ischemic ECG changes and excessive body mass were significant contributors to the total risk of cardiovascular death.

Prevalence of ischemic heart disease, coronary risk factors, and nutritional habits in samples of urban aboriginal and migrant male populations in some geographical regions were correlated with postmortem extent of vascular atherosclerotic lesions. Nationality associated characteristics of development of atheroslerosis were revealed: in migrant compared to autochthon men higher risk factor profile and atherogenic diet corresponded to greater extent of vascular atherosclerosis and more pronounced lumen obstruction.