Abstract
INTRODUCTION: Emerging research has documented that having a non-citizen status (e.g., temporary visa, undocumented) induces stress and, as a result, has adverse impacts on health. It is unclear whether chronic stress differs by citizenship status and length of U.S. residency using clinical biomarkers. The objective of this study was to examine allostatic load (or cumulative stress) by citizenship status and length of U.S. residency among U.S. adults. METHODS: The study sample included 27,705 adult respondents (aged ≥20 years) from the 2009-2018 National Health and Nutrition Examination Surveys. Multivariable Poisson regression models were estimated with U.S. citizenship status (U.S.-born citizens, naturalized citizens, noncitizens) and U.S. residency (shorter: <15 years, longer: ≥15 years) on allostatic load. Allostatic load was defined with summative scores of 10 biomarkers (systolic blood pressure, diastolic blood pressure, high-density lipoprotein, total cholesterol, HbA1c, BMI, albumin, estimated glomerular filtration rate, white blood cell count, and asthma). RESULTS: Naturalized citizens with shorter U.S. residency (females only) and noncitizens with shorter U.S. residency had lower allostatic load than U.S.-born citizens. Naturalized citizens with longer U.S. residency had greater allostatic load than naturalized citizens with shorter U.S. residency (females only). Noncitizens with longer U.S. residency had higher allostatic load than both noncitizens with shorter U.S. residency and naturalized citizens with shorter U.S. residency (females only). CONCLUSIONS: This study demonstrates nuanced impacts on allostatic load by citizenship status and length of U.S. residency, with differences by sex. The findings infer that citizenship status contributes to health inequities among immigrants, with greater attention needed to unpack citizenship-stress mechanisms.