Abstract 400: Cardiometabolic Profile Of Haptoglobin Genotype In A Multi-Ethnic Diabetes Cohort

Abstract

Background: Haptoglobin has three common genotypes: Hp 1-1, Hp 2-1, and Hp 2-2. The Hp 2-2 genotype, known to have poorer antioxidizing capacity, is associated with worse cardiovascular outcomes in select patients with diabetes. In this study, we explore the association between various cardiometabolic biomarker profiles and the three Hp genotypes in a multiethnic population. Methods: A cross-sectional analysis was performed for all participants with diabetes in the Dallas Heart Study and Multi-Ethnic Study of Atherosclerosis cohorts. Hp genotype was measured in 1,158 participants (399 from DHS and 759 from MESA) using ELISA technique (Savyon Diagnostics, Ltd). Associations between Hp genotype and 26 cardiometabolic circulating and imaging biomarkers were assessed by ANOVA and stratified by ethnicity. Results: The study included 51% women, 44% Black (513 of 1,158: Hp 1-1=45%, Hp 2-1=35%, Hp 2-2=20%), 26% Hispanic (300 of 1,158: Hp 1-1=25%, Hp 2-1=49%, Hp 2-2=26%), 20% White (237 of 1,158: Hp 1-1=16%, Hp 2-1=56%, Hp 2-2=28%), and 9.2% Asian/Pacific Islander/East Indian (107 of 1,158: Hp 1-1=15%, Hp 2-1=36%, Hp 2-2=49%) participants. Significant differences were seen in lipid metabolism as well as atherosclerosis, inflammatory, structural, and endothelial markers with no significant differences seen in imaging biomarkers. In White participants, Hp 1-1 was associated with elevated total cholesterol (p=0.016), LDL-p (p=0.001), and LDL-C (p=0.004). In Asian/Pacific Islander/East Indian participants, Hp 2-2 was associated with elevated systolic blood pressure (p=0.029), BMI (p=0.029), and inflammatory markers such as IL-6 (p=0.018) and D-dimer (p=0.027). In Black participants, Hp 2-2 was associated with elevated ICAM (p=0.048) and BMI (p=0.007). Lastly, in Hispanic participants, no significant associations were seen. In exploratory analysis, when comparing Hp 1-1 and Hp 2-1 with Hp 2-2, there was greater magnitude effect size of certain biomarkers in Black and Asian participants, suggesting potential differential effects by ethnicity. Conclusion: Associations between Hp genotype and various cardiometabolic biomarkers are varied and ethnicity dependent with further studies needed to investigate the underlying physiologic mechanisms.