Does hospital overload increase the risk of death when infected by SARS-CoV-2?

Abstract

Several studies found an association between the risk of death for COVID-19 patients and hospital overload during the first pandemic wave. We studied this association across the French departments using 82,467 serological samples and a hierarchical Bayesian model. In high-incidence areas, we hypothesized that hospital overload would increase infection fatality rate (IFR) without increasing infection hospitalization rate (IHR). We found that increasing departmental incidence from 3% to 9% rose IFR from 0.42% to 1.14%, and IHR from 1.66% to 3.61%. An increase in incidence from 6% to 12% in people under 60 was associated with an increase in the proportion of people over 60 among those infected, from 11.6% to 17.4%. Higher incidence did increase the risk of death for infected persons, probably due to an older infected population in high-incidence areas rather than hospital overload.