medRxiv. 2020 Sep 2:2020.08.31.20184036. doi: 10.1101/2020.08.31.20184036. Preprint.
Covid-19 excess deaths refer to increases in mortality over what would normally have been expected in the absence of the Covid-19 pandemic. In this study, we take advantage of spatial variation in Covid-19 mortality across US counties to construct an Ordinary Least Squares regression model estimating its relationship with all-cause mortality. We then examine how the extent of excess mortality not assigned to Covid-19 varies across subsets of counties defined by demographic, structural, and policy characteristics. We estimate that 20.4% [95% CI (13.7%, 27.2%)] of excess deaths between February 1 and August 26, 2020 were ascribed to causes of death other than Covid-19 itself. Excess deaths not assigned to Covid-19 were even higher than predicted by our model in counties with high income inequality, low median income, low homeownership, and high percentages of Black residents, showing a pattern related to socioeconomic disadvantage and structural racism. Our work suggests that inequities in excess deaths attributable to Covid-19 may be even greater than revealed by data reporting deaths assigned to Covid-19 alone.