Local Wealth Inequality and Working-Age Mortality in US Counties
Manuel Schechtl, Rourke O’Brien, Elizabeth Bair, Emma Zang, Atheendar S. VenkataramaniImportance
Household wealth is associated with health and survival, but little is known about whether wealth inequality is associated with mortality as a contextual exposure.
Objective
To examine the association between local wealth inequality and age-adjusted all-cause mortality across US counties over 5 decades.
Design, Setting, and Participants
This longitudinal, county-level study of up to 18 344 county-year observations from 1970 to 2019 linked restricted-access, all-cause mortality data from the US National Center for Health Statistics with county-level population and sociodemographic information and commuting zone estimates of household wealth inequality from the GEOWEALTH-US database. US counties were observed at decennial intervals from 1970 to 2019, with 2019 mortality used for the final period to avoid distortion from the COVID-19 pandemic. After listwise deletion, the estimation sample included up to 18 344 county-year observations nested in 732 commuting zones.
Exposure
Commuting zone Gini index score of household net wealth inequality.
Main Outcomes and Measures
County-specific, sex-specific, age-adjusted all-cause mortality rates for ages 25 to 44, 45 to 54, and 55 to 64 years, modeled on the natural log scale.
Results
In adjusted 2-way fixed-effects models with county, year, and state by year fixed effects, higher local wealth inequality was associated with higher mortality across all sex-age groups. Unstandardized regression coefficients (
Conclusions and Relevance
In this aggregate longitudinal cross-sectional study, increases in local wealth inequality were associated with within-county increases in working-age mortality. These findings suggest that wealth inequality may be relevant to population health beyond income inequality, although mechanisms and causality require further study.