Physiologic Dysregulation Experienced By Immigrants Is Mitigated By Immigrating At A Younger Age And Family Reunification: The Africans In America Study

Introduction: Immigration from Africa to the United States is stressful. Stress causes cardiovascular (CV), metabolic and immune dysregulation. Allostatic load score (ALS) quantifies the effect of dysregulation in these 3 systems. Objective: Our goal was to determine the influence of age of immigration, reason for immigration and unhealthy assimilation behavior on ALS in 238 African immigrants (AI) (age 40±10, mean±SD, range 21-64y). Methods: ALS was calculated using 10 variables, 6 were CV (SBP, DBP, triglyceride, cholesterol, homocysteine), 4 were metabolic (BMI, A1C, albumin, eGFR) and 1 was immune (CRP). Each variable was divided into sex-specific quartiles. High risk was defined by the highest quartile for each variable except albumin and eGFR which were defined by the lowest quartile. Each biomarker was assigned 1 point if in the high risk quartile and 0 if not. Unhealthy assimilation behavior was defined by increases in smoking, alcohol intake and sedentary activity after living in the US for ≥10y. Results: At enrollment all AI were adults (≥18y). Overall, 16% of AI were childhood immigrants (arrived in US <18y); 84% were adulthood immigrants (arrived in US≥18y). Compared to adulthood AI, childhood AI were younger (30±7 vs. 42±9, P <.01) and lived in the US longer (20±8 vs. 12±9y, P <.01). Age-adjusted ALS were similar in childhood and adult AI (2.78±1.83 vs. 2.73±1.69, P =.87). In multiple regression analysis (adjR 2 =0.24), older age at immigration and more years in the US were associated with higher ALS. Whereas current age, education and income had no effect on ALS. Reasons for immigration were: family reunification, work, study, marriage, lottery and asylum. Compared to all other reasons combined, immigration for family reunification was associated with the lowest ALS (1.94±1.51 vs. 3.03±1.86, P =.03). Smoking, alcohol intake and physical activity did not differ in adulthood AI living in the US for <10y vs. ≥10y (all P ≥.2) suggesting AI do not develop unhealthy assimilation behaviors. Conclusions: As measured by ALS, the physiologic dysregulation, experienced by AI is mitigated by younger age of immigration and family reunification. To decrease ALS in AI, family reunification may be more valuable than lifestyle intervention or medical therapy.