Abstract P193: High Density Lipoprotein is Superior to Triglyceride as a Biomarker of Physiologic Stress in African Immigrants: The Africans in America Study

Abstract

Introduction: For Africans living in the United States, the extent to which stress-induced physiologic dysfunction varies by reason for immigration is unknown. Allostatic load score (ALS) is used to assess physiologic stress. ALS has biomarkers in 3 domains: cardiovascular, metabolic and immune. However, there are many ALS equations and the number of biomarkers in each domain varies. In the cardiac domain of ALS, equations use either triglyceride (TG) or high density lipoprotein (HDL). A specific problem for African descent populations is that HDL may be superior to TG as a marker of insulin resistance and cardiac risk. Objective: Our primary goal in 95 African immigrants (71% male, age 42±10, (mean±SD), range 22-62y) was to determine if ALS varied by reason for immigration. Our secondary goal was to evaluate 4 different ALS equations to determine if there was a difference in ALS performance depending on whether HDL or TG was the included biomarker. Methods and Results: For all 4 equations, the reasons for immigration from lowest to highest ALS were: family reunification, lottery for self and immediate family, marriage, asylum, work and study (Figure 1). As the first 3 reasons for immigration promoted family unity, they were grouped together (Group 1). The Africans who came for other reasons were grouped together (Group 2). Equations 1 and 2 included HDL as a biomarker. For these equations, ALS in Group 1 vs. Group 2 were: 1.7±1.3 vs. 2.8±1.7, P <0.01 and 1.4±1.2 vs. 2.3±1.7, P <0.01 resp. Equations 3 and 4 used TG. For these two equations ALS in Group 1 vs. Group 2 were: 2.2±1.6 vs. 2.9±2.0, P =0.08 and 2.1±1.4 vs. 2.9±2.0, P =0.03 resp. In Equations 1 and 2, when HDL was replaced by TG, the significant difference in ALS between groups declined. In Equations 3 and 4, when TG was replaced by HDL, the significant difference in ALS between groups increased. Conclusions: ALS varies by reason for immigration and is easier to detect in ALS equations which use HDL rather than TG.