Anemia during SARS-CoV-2 infection is associated with rehospitalization after viral clearance

June 24 2021

Patients with COVID-19 can experience symptoms and complications after viral clearance. It is important to identify clinical features of patients who are likely to experience these prolonged effects. We conducted a retrospective study to compare longitudinal laboratory test measurements (hemoglobin, hematocrit, estimated glomerular filtration rate, serum creatinine, and blood urea nitrogen) in patients rehospitalized after PCR-confirmed SARS-CoV-2 clearance (n = 104) versus patients not rehospitalized after viral clearance (n = 278). Rehospitalized patients had lower median hemoglobin levels in the year prior to COVID-19 diagnosis (Cohen's D = −0.50; p = 1.2 × 10−3) and during their active SARS-CoV-2 infection (Cohen's D = −0.71; p = 4.6 × 10−8). Rehospitalized patients were also more likely to be diagnosed with moderate or severe anemia during their active infection (Odds Ratio = 4.07; p = 4.99 × 10−9). These findings suggest that anemia-related laboratory tests should be considered in risk stratification algorithms for patients with COVID-19.


Patrick Lenehan, Eshwan Ramudu, AJ Venkatakrishnan, Gabriela Berner, Reid McMurry, John C. O’Horo, Andrew D. Badley, William G. Morice II, John Halamka, Venky Soundararajan

nference, Cambridge, MA 02142, USA Mayo Clinic, Rochester, MN 55905, USA

Mayo Clinic


Correspondence to:

Venky Soundararajan (