Immunogenicity after six months of BNT162b2 vaccination in frail or disabled nursing home residents: the COVID-A Study
Author(s)
Ríos, Sergio Salmerón
Zamora, Elisa Belén Cortés
Céspedes, Almudena Avendaño
Rizos, Luis Romero
Sánchez-Jurado, Pedro Manuel
Type
Journal Article
Abstract
BACKGROUND: There is incomplete information regarding evolution of antibody titers against SARS-CoV-2 after a two-dose strategy vaccination with BNT162b2, in older adults in long-term care facilities (LTCFs) with frailty, disability or cognitive impairment. We aimed to determine IgG antibody titer loss in old adults in LTCFs. METHODS: Multicenter longitudinal cohort study including 127 residents (90 females, 37 males) with a mean age of 82.7 years (range 65-99) with different frailty and disability profiles in two LTCFs in Albacete, Spain. Residents received 2 doses of BNT162b2 as per label, and antibody levels were determined 1 and 6 months after the second dose. Age, sex, previous history of COVID-19, comorbidity (Charlson index), performance in activities of daily living (Barthel index), frailty (FRAIL instrument), and cognitive status were assessed. RESULTS: The mean antibody titers 1 and 6 months after the second vaccine dose were 32,145 AU/mL (SD 41,206) and 6,182 AU/mL (SD 13,316) respectively. Across all participants, the median antibody titer loss measured 77.6% (IQR 23.8%). Notably, the decline of titers in individuals with pre-vaccination COVID-19 infection was significantly lower than in those without history of SARS-CoV-2 infection (72.2% vs 85.3%; p<.001). The median titer decrease per follow-up day was 0.47% (IQR 0.14%) and only pre-vaccination COVID-19 was associated with lower rate of antibody decline at 6 months (HR 0.17; 95% CI 0.07-0.41; p<.001). Frailty, disability, older age, cognitive impairment, or comorbidity were not associated with the extent of antibody loss. CONCLUSIONS: Older adults in LTCFs experience a rapid loss of antibodies between over the first six months after the second dose of BNT162b2 vaccine. Only pre-vaccination COVID-19 is associated with a slower rate of antibodies decrease. Our data support immunization with a third dose in this vulnerable, high-risk population. This article is protected by copyright. All rights reserved.
Date Issued
2022-03
Date Acceptance
2021-12-05
Citation
Journal of the American Geriatrics Society, 2022, 70 (3), pp.650-658
ISSN
0002-8614
Publisher
Wiley
Start Page
650
End Page
658
Journal / Book Title
Journal of the American Geriatrics Society
Volume
70
Issue
3
Copyright Statement
© 2021 The American Geriatrics Society. . This is the peer reviewed version of the following article, which has been published in final form at https://agsjournals.onlinelibrary.wiley.com/doi/10.1111/jgs.17620. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.
Sponsor
National Institute for Health Research
Imperial College Healthcare NHS Trust- BRC Funding
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/34894403
Grant Number
NIHR-RP-011-053
RDB01 79560
Subjects
BNT162b2 vaccine
COVID-19
Disability
Frailty
Immunogenicity
Older adults
Publication Status
Published
Coverage Spatial
United States
Date Publish Online
2021-12-11