Socioeconomic disparity in cardiovascular disease: a proteomic approach

Abstract

Abstract Background and purpose A large unexplained social disparity in the occurrence of cardiovascular disease (CVD) has been documented. The precise mechanism behind these disparities is largely unknown. Biomarkers have improved our understanding of the pathophysiology of CVD. In this study we investigated differences in 184 biomarkers linked to CVD, with the aim of understanding the underlying mechanisms behind socioeconomic disparity in CVD and explore potential preventive measures. Methods We included 1144 participants from the Copenhagen City Heart Study, age 55- 64 years, without known CVD. Socioeconomic position (SEP) was defined by educational length in years. Blood samples were obtained and analyzed in two CVD proteomics panels (CVD panel II and III) with a total of 184 protein biomarkers. Associations between biomarkers and SEP were investigated by Pearson correlation coefficient and linear regression with multivariate adjustment for CVD risk factors. Results Median educational length was 10 (IQR 7–11) years. Of the measured biomarkers 53 were significantly correlated (p value <0.05) to educational length, 17 positively and 36 negatively (fig. 1). After adjusting for age and gender, 41 biomarkers and after multivariate adjustment 14 biomarkers remained significantly associated with educational length. Some of the strongest negative associations was seen for Leptin (LEP), Von Willebrand factor (vWF), Interleukin-6 (IL6), Fibroblast growth factor 21 (FGF21), Renin (REN) and Growth/differentiation factor 15 (GDF_15) while the strongest positive associations were seen for Growth Hormone (GH), Receptor for advanced glycosylation end products (RAGE) and Myoglobin (MB) (fig. 2). Conclusion SEP was associated with elevated levels of multiple biomarkers linked with CVD. The range of biomarkers indicate that pathways involving inflammation (IL6, LEP, RAGE), platelet-activation (vWF, IL6, RAGE), blood pressure (REN, LEP), MAPK cascade (GDF_15, FGF21, LEP, IL6, REN, GH) and weigh (LEP) regulation contribute to the socioeconomic gradient in CVD. Further exploration is needed to identify possible candidates for intervention. Funding Acknowledgement Type of funding sources: Public hospital(s). Main funding source(s): Department of Cardiology, Bispebjerg University Hospital, Copenhagen, Denmark.