Community Predictors of COVID-19 Cases and Deaths in Massachusetts:
Evaluating Changes Over Time Using Geospatially Refined Data
Abstract
Background: The COVID-19 pandemic has highlighted the need for targeted
local interventions given substantial heterogeneity within cities and
counties. Publicly available case data are typically aggregated to the
city or county level to protect patient privacy, but more granular data
are necessary to identify and act upon community-level risk factors that
can change over time. Methods: Individual COVID-19 case and mortality
data from Massachusetts were geocoded to residential addresses and
aggregated into two time periods: “Phase 1” (March–June 2020) and
“Phase 2” (September 2020–February 2021). Institutional cases
associated with long-term care facilities, prisons, or homeless shelters
were identified using address data and modeled separately. Census tract
sociodemographic and occupational predictors were drawn from the
2015-2019 American Community Survey. We used mixed-effects negative
binomial regression to estimate incidence rate ratios (IRRs), accounting
for town-level spatial autocorrelation. Results: Case incidence was
elevated in census tracts with higher proportions of Black and Latinx
residents, with larger associations in Phase 1 than Phase 2. Case
incidence associated with proportion of essential workers was similarly
elevated in both Phases. Mortality IRRs had differing patterns from case
IRRs, decreasing less substantially between Phases for Black and Latinx
populations and increasing between Phases for proportion of essential
workers. Mortality models excluding institutional cases yielded stronger
associations for age, race/ethnicity, and essential worker status.
Conclusions: Geocoded home address data can allow for nuanced analyses
of community disease patterns, identification of high-risk subgroups,
and exclusion of institutional cases to comprehensively reflect
community risk.