COVID-19 convalescent plasma utilization patterns among hospitalized u.s. Medicare beneficiaries ages 65 and older diagnosed with COVID-19, 2020-2021

Abstract

Abstract Introduction: In August 2020, COVID-19 convalescent plasma (CCP) was authorized for emergency use for the treatment of hospitalized COVID-19 patients. Assessment of real-world CCP use can help to understand factors influencing the demand during the pandemic. The study evaluated CCP use among inpatient fee-for-service Medicare beneficiaries age 65+ with COVID-19 during August 2020-December 2021. Methods: This retrospective study uses diagnosis and procedure codes to identify COVID-19 status and CCP administrations, respectively, in Medicare data. We assessed CCP use prevalence per 100 COVID-19 inpatient stays overall, monthly and by U.S. Census Regions, area deprivation index (ADI), and other recipient and hospital characteristics. COVID-19 severity measures included: inpatient mortality, mechanical ventilation (MV), ICU/CCU admission, and length of stay (LOS). Cochran-Armitage tests ascertained CCP use trends by admission month. Results: Among 775,821 inpatient COVID-19 stays, 87,242 (11.25%) had a recorded CCP administration. Monthly CCP use prevalence increased from August 2020 (11.14%) through October 2020 (22.49%), with an overall significant (p<0.001) decline through December 2021 (0.32%). Among COVID-19 stays, we observed significantly different CCP use (p<0.0001) in those with (17.06%) and without (7.37%) ICU/CCU admission as well as by ventilation status (10.10% with no MV, 16.73% with MV<96hr, and 23.81% with MV≥96hr). We also observed significant differences (p<0.0001) by ADI, hospital characteristics, and region, among other characteristics. Inpatient stays with COVID-19 recorded 11-30 days prior to admission had among the lowest CCP prevalence of 5.07%. Stays with CCP use vs. all COVID-19 stays had: LOS>10 days (43.25% vs. 30.11%), ICU/CCU admission (60.63% vs. 39.97%), MV≥96 hours (13.41% vs. 6.33%), and inpatient mortality (27.22% vs. 16.87%). Conclusions: Our investigation shows variation of CCP utilization over time and by various characteristics among hospitalized Medicare beneficiaries aged 65+ with COVID-19. Declining CCP use from October 2020 through December 2021 may be related to increasing availability of other COVID-19 treatments and vaccinations, emerging randomized trial evidence for CCP, and revised conditions of authorization. CCP use prevalence was higher for residents of the South; with lower ADI; with ICU/CCU admission; and with MV; among others. Overall, differences identified in CCP utilization may be due to variations in COVID-19 severity, recency of COVID-19 infection, socioeconomic status, hospital characteristics, and underlying comorbidities.