Based on intrafamilial correlations, a component genetic analysis was used to evaluate the contribution made by genetic and environmental factors to variance in body weight and skin fold thickness in children who had various blood pressure. In children with initially elevated and normal blood pressures, the phenotypic variation in the body weight and adipopexia is largely determined by genetic factors, whereas in those with initially lower blood pressure, the phenotypic variation in the above parameters is greatly affected by environmental factors, mainly by those of occasional nature. The findings provide evidence for a differential approach to the primary prevention of hyper- and hypotension in children and adolescents.

As part of a programme designed to determine precursors of arterial hypertension and atherosclerosis in children and adolescents, a cross-sectional study involving the groups of families whose children had different baseline arterial pressure levels was conducted. An association between the level of arterial pressure in the children and the blood pressure levels and prevalence of cardiovascular diseases in their first-degree relatives was found. The most informative signs for decreased and increased arterial blood pressure levels in children were identified. The findings should be taken into account when selecting groups of children who require close medical surveillance.

Blood lipid and lipoprotein concentrations were measured in proband children with different levels of arterial pressure and in their relatives in the populational familial study. Based on intrafamilial correlations the component analysis of the phenotypic dispersion of total cholesterol, high density lipoprotein cholesterol and triglyceride concentrations was performed. Qualitative and quantitative differences were shown to exist in genetic and environmental determinants of lipids and lipoproteins in the families of probands with low, high and normal levels of arterial pressure.

Contribution of genetic and environmental factors into phenotypic variability of blood pressure and body mass as well as into phenotypic correlation between these traits was defined. It was shown that additive genetic determinant is responsible for considerable level of blood pressure and body mass variability. Those common environmental factors are of importance which operate within the limits of one generation. Maternal effect of systolic and diastolic blood pressure variability is negligible. The correlation between systolic and diastolic blood pressure is determined both by environmental and genetic factors, whereas that between blood pressure and body mass is mediated by only environmental factors. The contribution of environmental factors into correlation between blood pressure and body mass lessens with age. The results obtained may be applied in development of population and individual programmes for preventing cardiovascular diseases.

Three groups of families with different initial levels of arterial pressure in proband children were examined. The relationship was established between the levels of arterial pressure in children and those in their relatives of the first degree of kinship. Based on intrafamilial correlations, the phenotypic dispersion of systolic and diastolic arterial pressure was analyzed. It has been shown that as compared to the genetic factors, the environmental factors play a greater role in arterial pressure variability.