Lawton Ralph, Zheng Kevin, Zheng Daniel, Huang Erich
Department of Economics, Duke University, 213 Social Sciences, 419 Chapel Drive, Durham, North Carolina, US.
Department of Biostatistics and Bioinformatics, Duke University Medical Center, 2424 Erwin Road, Suite 1102 Hock Plaza, Box 2721, Durham, North Carolina, US.
Lancet Reg Health Am. 2021 Sep;1:100011. doi: 10.1016/j.lana.2021.100011. Epub 2021 Jul 13.
Non-Hispanic Black populations have suffered much greater per capita COVID-19 mortality than White populations. Previous work has shown that rates of Black and White mortality have converged over time. Understanding of COVID-19 disparities over time is complicated by geographic changes in prevalence, and some prior research has claimed that regional shifts in COVID-19 prevalence may explain the convergence.
Using county-level COVID-19 mortality data stratified by race, we investigate the trajectory of Black and White per capita mortality from June 2020-January 2021. We use a county fixed-effects model to estimate changes within counties, then extend our models to leverage county-level variation in prevalence to study the effects of prevalence versus time trajectories in mortality disparities.
Over this period, cumulative mortality rose by 61% and 90% for Black and White populations respectively, decreasing the mortality ratio by 0.4 (25.8%). These trends persisted when a county-level fixed-effects model was applied. Results revealed that county-level changes in prevalence nearly fully explain changes in mortality disparities over time.
Results suggest mechanisms underpinning convergence in Black/White mortality are not driven by fixed county-level characteristics or changes in the regional dispersion of COVID-19, but instead by changes within counties. Further, declines in the Black/White mortality ratio over time appear primarily linked to county-level changes in COVID-19 prevalence rather than other county-level factors that may vary with time. Research into COVID-19 disparities should focus on mechanisms that operate within-counties and are consistent with a prevalence-disparity relationship.
This work was supported by the National Center for Advancing Translational Sciences [E.H.: UL1TR002553].
非西班牙裔黑人人群的人均新冠病毒疾病（COVID-19）死亡率比白人人群高得多。此前的研究表明，黑人和白人的死亡率随着时间的推移已趋于一致。由于患病率的地理变化，对COVID-19差异随时间变化的理解变得复杂，一些先前的研究声称，COVID-19患病率的区域变化可能解释了这种趋同现象。
我们使用按种族分层的县级COVID-19死亡率数据，调查了2020年6月至2021年1月期间黑人和白人的人均死亡率轨迹。我们使用县级固定效应模型来估计各县内部的变化，然后扩展我们的模型，利用县级患病率的变化来研究患病率与死亡率差异的时间轨迹之间的关系。
在此期间，黑人和白人人群的累积死亡率分别上升了61%和90%，死亡率之比下降了0.4（25.8%）。应用县级固定效应模型时，这些趋势依然存在。结果显示，县级患病率的变化几乎完全解释了死亡率差异随时间的变化。
结果表明，黑/白死亡率趋同的潜在机制不是由固定的县级特征或COVID-19区域分布的变化驱动的，而是由各县内部的变化驱动的。此外，随着时间的推移，黑/白死亡率之比的下降似乎主要与县级COVID-19患病率的变化有关，而不是与其他可能随时间变化的县级因素有关。对COVID-19差异的研究应关注在县内起作用且与患病率-差异关系一致的机制。
这项工作得到了美国国立转化医学推进中心[E.H.：UL1TR002553]的支持。
