Primary Submission Category: Mortality
Excess Mortality in US Metropolitan Areas from January 2020 to December 2021
Authors: Edwin McCulley Alina Schnake-Mahl Heather Rollins Kevin Martinez-Folgar Bricia Trejo
Presenting Author: Edwin McCulley*
COVID-19 has emerged as a leading cause of death in the United States (US), with nearly 1.3 million COVID-19 deaths in the US since 2020. However, the true burden of COVID-19 mortality is underestimated by the use of counts of directly reported COVID-19 deaths, whether from COVID-19 surveillance data or from vital registration systems. Excess mortality is a common metric to measure the impact of discrete events (e.g., natural disasters, epidemics) on population health and is estimated by comparing observed deaths to those expected to occur in the absence of the event (i.e., a counterfactual). Excess mortality estimates are therefore less prone to measurement error due to cause of death coding differences and allow for the examination of the direct and indirect effects of the pandemic on mortality. While recent literature has quantified pandemic related excess mortality in US states and counties, an estimation of this metric using functional city definitions (e.g., metropolitan statistical areas) is lacking. Moreso, previous studies have yet to examine how age-specific excess mortality varies across the urban continuum. To this end, we aim to examine how the COVID-19 pandemic affected all-cause mortality in US metropolitan areas by year, month, and age group. Cities were delineated based on 3 different urbanicity definitions and linked to county level population and mortality data. We estimated a quasi-Poisson generalized linear model based on historical mortality data from 2015-2019 and used this model to estimate age-specific rates of excess mortality for 2020 and 2021. Estimating excess mortality at the city-level allows us to better understand the pandemics true burden by examining its differential impact on all-cause mortality across US cities.