Is Low Neighborhood Socioeconomic Status Linked to Higher Premature Mortality Rates?

This study investigates whether lower neighborhood socioeconomic status (SES) throughout life is associated with an increased risk of premature mortality. Using data from 12,610 participants in the Atherosclerosis Risk in Communities (ARIC) study, researchers linked residential SES during childhood, young adulthood, and middle adulthood to all-cause mortality before age 75. They found that low neighborhood SES in middle adulthood was associated with a 28% higher risk of premature mortality, with persistent low SES from young to middle adulthood increasing the risk by 25%. Findings highlight the long-term impact of sustained socioeconomic disadvantage on early mortality risk.

Central Research Question

This study explores the impact of neighborhood socioeconomic status (SES) throughout various life stages on premature mortality risk, defined as death before age 75. The primary research question is whether residing in low-SES neighborhoods from childhood through middle adulthood contributes to a higher likelihood of early mortality. By evaluating neighborhood SES across different life stages, the researchers aim to understand how socioeconomic disadvantage over time may influence long-term health outcomes and mortality rates.

Previous Literature

Research has consistently linked low SES with various adverse health outcomes, including chronic disease and premature mortality. However, most studies focus on a single assessment of SES, often during middle or older adulthood, without considering SES exposure earlier in life or across multiple life stages. Previous studies have shown that living in disadvantaged neighborhoods can lead to higher chronic disease rates due to limited access to healthcare, healthy food, safe recreational areas, and quality housing. Additionally, SES-related stressors and limited opportunities in low-SES neighborhoods can compound over time, leading to cumulative health impacts. Some evidence suggests that women, in particular, may face greater mortality risks in low-SES neighborhoods due to compounded psychosocial stress and limited mobility opportunities. However, research on how SES disadvantages across the life course affect mortality has been limited, especially studies using longitudinal data that can capture SES changes over time.

Data

The researchers used data from the Atherosclerosis Risk in Communities (ARIC) study, a large, multicenter prospective cohort study that enrolled participants from four U.S. communities—Washington County, Maryland; Forsyth County, North Carolina; Jackson, Mississippi; and the suburbs of Minneapolis, Minnesota. This study involved 12,610 Black and White participants, with a baseline age average of 62.6 years. Participants’ residential addresses were obtained for three life stages: childhood (age 10), young adulthood (age 30), and middle adulthood (ages 40 to 50). The study linked these addresses to census-based socioeconomic indicators, such as educational attainment, income, property values, home ownership, and occupation. This data linkage allowed for the creation of summary neighborhood SES scores for each life stage.

The primary outcome measure was premature mortality, or death occurring before age 75. Mortality data was gathered through participant proxies, obituaries, hospital records, death certificates, and the National Death Index. The average follow-up period for participants was 18.8 years, from 1996 to 2020.

Methods

The study classified neighborhood SES for each life stage (childhood, young adulthood, and middle adulthood) into tertiles (low, middle, and high) based on census-based z-scores. To examine the effect of persistent low SES, the researchers calculated cumulative adulthood SES by combining scores from young and middle adulthood. Additionally, they created categories to capture SES changes, such as “low-to-low” (stable low SES), “high-to-high” (stable high SES), “low-to-high” (SES improvement), and “high-to-low” (SES decline) across life epochs. Individual SES, including factors like education, occupation, income, and home ownership, was also assessed as a covariate to evaluate any interactions between individual and neighborhood SES on mortality outcomes.

To estimate the association between neighborhood SES and premature mortality, the researchers used Cox proportional hazards models. The models were adjusted for age, sex, study center, race, income, and marital status to account for sociodemographic confounding factors. Poisson regression models and Kaplan-Meier analyses were also used to analyze mortality rates across SES tertiles and visualize cumulative mortality risk.

Findings/Size Effects

The analysis showed significant associations between lower neighborhood SES in middle adulthood and a higher risk of premature mortality. Key findings include:

Middle Adulthood SES: Individuals in the lowest neighborhood SES tertile during middle adulthood had a 28% higher risk of premature mortality compared to those in the highest tertile, even after adjusting for demographic and socioeconomic factors. Among women, the risk was even greater, with a 39% increased risk in the lowest SES tertile compared to the highest.
Young Adulthood SES: Low neighborhood SES in young adulthood was also associated with premature mortality but showed more substantial effects in women. For women in the lowest SES tertile in young adulthood, the risk of premature mortality was 25% higher than for those in the highest SES tertile.
Childhood SES: The study found no significant association between childhood SES and premature mortality when analyzed independently, suggesting that the critical period for SES influence on premature mortality risk might start in early adulthood.
Cumulative Adulthood SES: When considering cumulative SES across adulthood, individuals in the lowest tertile had a 20% higher risk of premature mortality than those in the highest tertile, highlighting the cumulative effect of sustained low neighborhood SES. The impact was particularly pronounced among women and among individuals with low individual SES, underscoring the compounded effects of both individual and neighborhood SES on health outcomes.
SES Change Patterns: Participants whose neighborhood SES remained low from young adulthood to middle adulthood had a 25% higher risk of premature mortality than those with stable high SES. Additionally, those who moved from high to low SES neighborhoods experienced a slight increase in mortality risk compared to those who stayed in high SES neighborhoods, suggesting that transitioning into more socioeconomically disadvantaged areas may contribute to health declines.

Conclusion

This study highlights the importance of neighborhood SES throughout the life course on the risk of premature mortality. The findings underscore that sustained exposure to low neighborhood SES from young to middle adulthood is a critical factor in increasing premature mortality risk. Moreover, the study reveals that the adverse effects of low neighborhood SES are more significant among women and among individuals with lower individual SES, indicating that socioeconomic disadvantages at both the neighborhood and individual levels can compound to affect health outcomes.

The study contributes to the growing body of evidence on the health impacts of socioeconomic context and supports a life course perspective when addressing health disparities. By emphasizing that neighborhood SES in early and middle adulthood plays a significant role in mortality risk, the study suggests that public health interventions targeting neighborhood improvements and socioeconomic support could be effective strategies for reducing premature mortality. Place-based interventions that focus on improving neighborhood SES, particularly in socioeconomically disadvantaged communities, could alleviate some of the long-term health risks associated with poverty and create more equitable health outcomes across the life span.

Citation

Lawrence, W. R., Kucharska-Newton, A. M., Magnani, J. W., Brewer, L. C., Shiels, M. S., George, K. M., Lutsey, P. L., Jenkins, B. D., Sullivan, K. J., Carson, A. P., & Freedman, N. D. (2024). Neighborhood Socioeconomic Disadvantage Across the Life Course and Premature Mortality. JAMA Network Open, 7(8), e2426243. https://doi.org/10.1001/jamanetworkopen.2024.26243