To what extent do biomarkers account for the large social disparities in health in Moscow?

The Russian population continues to face political and economic challenges, has experienced poor general health and high mortality for decades, and has exhibited widening health disparities. The physiological factors underlying links between health and socioeconomic position in the Russian population are therefore an important topic to investigate. We used data from a population-based survey of Moscow residents aged 55 and older (n = 1495), fielded between December 2006 and June 2009, to address two questions. First, are social disparities evident across different clusters of biomarkers? Second, does biological risk mediate the link between socioeconomic status and health? Health outcomes included subscales for general health, physical function, and bodily pain. Socioeconomic status was represented by education and an index of material resources. Biological risk was measured by 20 biomarkers including cardiovascular, inflammatory, and neuroendocrine markers as well as heart rate parameters from 24-h ECG monitoring. For both sexes, the age-adjusted educational disparity in standard cardiovascular risk factors was substantial (men: standardized β = -0.16, 95% CI = -0.23 to -0.09; women: β = -0.25, CI = -0.32 to -0.18). Education differences in inflammation were also evident in both men (β = -0.17, CI = -0.25 to -0.09) and women (β = -0.09, CI = -0.17 to -0.01). Heart rate parameters differed by education only in men (β = -0.10, CI = -0.18 to -0.02). The associations between material resources and biological risk scores were generally weaker than those for education. Social disparities in neuroendocrine markers were negligible for men and women. In terms of mediating effects, biological risk accounted for more of the education gap in general health and physical function (19-36%) than in bodily pain (12-18%). Inclusion of inflammatory markers and heart rate parameters-which were important predictors of health outcomes-may explain how we accounted for more of the social disparities than previous studies.