The purpose of this study is to assess whether convalescent plasma therapy is associated with reduced 30-day all-cause mortality in a population of Veteran inpatients with non-severe coronavirus disease 2019 (COVID-19).
The convalescent plasma (CP) of individuals who have recovered from COVID-19 may help reduce
symptoms and mortality when given to ill patients infected with severe acute respiratory
syndrome coronavirus 2 (SARS-CoV-2). Clinical trials are needed to provide definitive
evidence of the benefits and harms of CP in the treatment of COVID-19. While clinical trials
are underway, observational research plays a critical role in providing preliminary
scientific evidence to guide clinical practice.
This observational study aims to estimate the association between CP therapy and mortality
after 30 days in a sample of SARS-CoV-2-positive patients with non-severe illness. Patients
include those hospitalized at a facility within the Veterans Health Administration (VHA) of
the Department of Veterans Affairs (VA), the largest integrated healthcare system in the
United States. Using VA electronic health record data, the study is designed to emulate a
target trial of convalescent plasma transfusion and mortality. The primary exposure of
interest is the use or non-use of COVID-19 convalescent plasma, and the primary outcome is
30-day all-cause mortality.
A nested trial design will be used, in which patients will be followed from each day in which
eligibility criteria are met (while hospitalized and after date of first positive SARS-CoV-2
test) for 30 days. The association between CP therapy and mortality will be assessed using
pooled logistic models to estimate 30-day cumulative incidence curves, risk differences, and
hazard ratios. Inverse probability weighting derived from propensity scores will be employed
to minimize confounding by indication and other biases.
Biological: COVID-19 convalescent plasma
Convalescent plasma collected from individuals who have recovered from COVID-19
Inclusion Criteria:
- US Veterans aged 21-80 years old
- Hospitalized between May 1, 2020 and November 17, 2020 with a SARS-CoV-2 positive
test, at a VA Medical Center where convalescent plasma had been administered to at
least one patient and remained a current practice at that VA Medical Center
- SARS-CoV-2 positive test within 7 days before or after hospital admission
- Minimum oxygen saturation (measured within the past day) >=90%
- Vitals (pulse, respiration, temperature, systolic blood pressure) and acute labs
(hemoglobin, platelet, white blood cells) measured within the past 2 days
- Albumin, Alanine Aminotransferase (ALT), creatinine measured within the past 30 days
- Weight measurement recorded in the past 2 years
Exclusion Criteria:
- Prior intubation, ventilation, high flow oxygen, ECMO, dialysis, or vasopressors
during current hospitalization
- Record of prior treatment with CP
- Received long-term care in a domiciliary or nursing home in the past 90 days
- First CP recipient at a site
- Less than 30 days of follow-up
VA Boston Healthcare System Jamaica Plain Campus, Jamaica Plain, MA
Boston, Massachusetts, United States
VA Puget Sound Health Care System Seattle Division, Seattle, WA
Seattle, Washington, United States