Primary Submission Category: Spatial Epidemiology
Socioeconomic Spatial Social Polarization and High Blood Pressure in the Cardiovascular Health Study (CHS) and REasons for Geographic and Racial Differences in Stroke (REGARDS) Study
Authors: Hoda Abdel Magid Gina Lovasi Andrea Rosso Annabel Tan Sherri Rose David Rehkopf Lorene Nelson Justin Feldman Suzanne Judd Michelle Carlson Michelle Odden
Presenting Author: Hoda Abdel Magid*
Spatial social polarization (SSP) indices are potentially key to understanding blood pressure disparities as the spatial patterning of blood pressure is hypothesized to be influenced by area-level socioeconomic risk factors. SSP indices measure the extent to which populations are distributed at extremes of privilege and deprivation of socioeconomic domains. The objective of this study is to compare socioeconomic SSP predictors of blood pressure outcomes in Black and White adults in the Cardiovascular Health Study (CHS) and the REasons for Geographic and Racial Differences in Stroke (REGARDS) study. We evaluated the use of the Index of Concentration at the Extremes (ICE) to measure SSP across three socioeconomic domains including race/ethnicity, income, joint race/ethnicity with income, and home ownership using 2010 census tract-level data. We computed quintiles for each ICE measure, with quintile 1 representing the most deprived groups and quintile 5 representing the most privileged for each SSP domain measured. High blood pressure was defined as a treated or untreated blood pressure >140/90 mmHg. The analytic sample included 5,888 CHS study participants ages ≥65 years at study entry (1989-1993) and 30,183 REGARDS study participants ages ≥45 years at study entry (2003-2007). Multilevel mixed-effect logistic regression models were adjusted for age, sex, race/ethnicity, diabetes, heart failure, kidney disease, and metastatic cancer, and stroke. We found the strongest associations for associations of SSP domains of combined race/ethnicity and income and disparities in high blood pressure. For example, we found that study participants who had had resided in the most polarized and disadvantaged quintile (Q1) had a 1.12 (95% 1.06, 1.23) and 1.15 (95% 1.07, 1.23) higher odds of high blood pressure compared to those in Q5 (Reference = 1) for the ICE jointly measuring race/ethnicity and income among CHS and REGARDS study participants, respectively. ICE measures for race/ethnicity alone, income alone, and home onwership were not associated with high bood pressure in either CHS or REGARDS. Joint economic and racial/ethnic polarization may be contribute to blood pressure disparities.