Abstract C051: Intersection of race/ethnicity and neighborhood socioeconomic status on all-cause mortality in California and Hawaii: The Multiethnic Cohort Study
Authors: Cheng Iona , Conroy Shannon M , Wilkens Lynne R , Shariff-Marco Salma , Yang Juan , Wu Anna H , Gomez Scarlett Lin , Marchand Loic Le 
Published: September 2020

Abstract
Background: The persistent inequality in health outcomes across race/ethnicity requires addressing the complex relationships of social determinants of health. We evaluated the joint effects of race/ethnicity, neighborhood socioeconomic status (nSES), and state of residence on all-cause mortality among African American, Japanese American, Latino, Native Hawaiian, and White participants of the Multiethnic Cohort Study (MEC). Methods: Baseline residential addresses of MEC participants (recruited at age 45-75 in 1993-1996) were geocoded and linked to census block group measures of nSES, composite scores based on California (CA) and Hawaii (HI) 1990 census data, capturing education, poverty, occupation, unemployment, income, and rental/property value. Cox proportional hazards models were used to examine the joint associations of race/ethnicity, nSES, and state of residence with all-cause mortality, adjusting for age, sex, smoking status, body mass index, physical activity, alcohol intake, total energy intake from fat, coffee intake, marital status, comorbidities, and clustering effects by census block group. All hazard ratios (HRs) were compared to Japanese Americans residing in high SES neighborhoods in HI as this group had the lowest mortality. Results: Among 186,034 MEC participants, there were 63,799 all-cause deaths from 1993-2013. All residents living in low SES neighborhoods, regardless of race/ethnicity and state, and several high SES groups exhibited significantly higher risk of mortality compared to the reference group. Japanese Americans residing in low SES neighborhoods experienced higher risk of mortality in HI (HR=1.11; 95% CI: 1.07-1.16) and CA (HR=1.13; 95% CI; 1.07-1.19). The higher risk among CA Latinos residing in low SES neighborhoods (HR=1.39; 95% CI: 1.35-1.44) was significantly greater (p&lt;0.01) than among their CA Latino counterparts in high SES neighborhoods (HR=1.24; 95% CI: 1.18-1.30). Whites residing in low SES neighborhoods in HI (HR=1.52; 95% CI: 1.45-1.59) had similar hazard ratios as Whites and African Americans residing in high SES neighborhoods in CA (HR=1.50; 95% CI: 1.42-1.58 and HR=1.47; 95% CI: 1.39-1.54, respectively). In addition, CA Whites residing in low SES neighborhoods experienced a similar hazard ratio (HR=1.74; 95% CI: 1.66-1.83) as CA African Americans residing in low SES neighborhoods (HR=1.75; 95% CI: 1.69-1.81). Native Hawaiians residing in low SES neighborhoods experienced the highest risk of mortality (HI HR=2.01; 95% CI: 1.90-2.13; CA HR=2.59; 95% CI: 1.86-3.61), while their counterparts in high SES neighborhoods in HI were also at elevated risk (HR=1.63 95% CI: 1.55-1.72). Conclusion: These findings illustrate how an intersectional approach can elucidate the interconnections between race/ethnicity and nSES on health outcomes. Future directions will further investigate cancer mortality and other cause-specific outcomes in relation to multilevel risk factors to generate clues on the reasons for these disparities.
Citation Format: Iona Cheng, Shannon M Conroy, Lynne R Wilkens, Salma Shariff-Marco, Juan Yang, Anna H Wu, Scarlett Lin Gomez, Loic Le Marchand. Intersection of race/ethnicity and neighborhood socioeconomic status on all-cause mortality in California and Hawaii: The Multiethnic Cohort Study [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr C051.