Biomarker «peak Height Velocity» as the Indicator of Secular Dynamics of Physical Status in Intergroup Studies/Comparisons

Abstract

Introduction. The goal of study is the estimation of «peak height velocity» (PHV) as the marker of secular trends in addition to secular dynamics of height (H). Material and methods. The study embraces the block of samples of scholars (6/7-17 years) from Russia and former USSR, examined through the vast historical period from 1920th till nowadays, literary data and personal archives of the authors. The main attention is paid to three urban agglomerations - Moscow, Nizhniy Novgorod, Minsk. The following number of parameters is determined for each sample: the age of maximal velocity of growth dynamics of average levels of H during adolescence (APHV), determined according to the empirical patterns of annual changes of average H levels and consequent smoothing by least square method - differentially for boys and girls; and delta between parameters of boys and girls; maximal quantitative level of growth changes in cm (IPHV), different for boys and girls as well, and delta between the parameters. Results. The difference of APHV between boys and girls for each population under study is about two years - boys have delayed PHV as compared to girls in any ecological niche. Secular dynamics of APHV has nonlinear character, doesn’t decrease progressively through the whole historical interval from 1920th to 2000th, despite of permanent increase of the level of anthropogenic stress in cities under analysis, the lowest APHV is fixed in 1980th. Correlations of APHV with absolute annual H values through the age interval 6/7-17 years is systematic and high enough for boys (correlation about 0,5, determination coefficient about 0,25) and accidental for girls, being revealed for only one annual age group among 12 analyzed. Correlations of IPHV with absolute values of H are maximal at 7 years and minimal at 17 years, the level of correlations is less for girls as compared to boys. Conclusion. PHV really marks the secular somatic dynamics along with H itself as genetic marker. Correlation of APHV with absolute annual levels of H through the interval 6/7-17 years is systematic and significant for boys and accidental for girls, which witness to genetic determination of growth tempo of boys. Correlation of IPHV with absolute values of H, having highest levels at 7 years, points to the fact that height at 7 years is a real trigger of PHV parameters.