Evidence map›Paper›PMID 32184579›Full record

ArticleClinical interventions in aging2020

A Population-Based Propensity Score-Matched Study to Assess the Impact of Repeated Vaccination on Vaccine Effectiveness for Influenza-Associated Hospitalization Among the Elderly.

Pi-Shan Hsu, Ie-Bin Lian, Day-Yu Chao

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Article in Clinical interventions in aging, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers.

0numbers the graph read from it
0cells of the map it votes in
6citing papers in PubMed
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1 · What the graph read from it

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

Who cites it

6 citing papers in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

3 authors.

Pi-Shan HsuDepartment of Family Medicine, Taichung Hospital, Ministry of Health and Welfare, Taichung, Taiwan.
Ie-Bin LianGraduate Institute of Statistics and Information Science, National Changhua University of Education, Changhua, Taiwan.
Day-Yu ChaoGraduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung-Hsing University, Taichung, Taiwan.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundInfluenza is a major cause of morbidity and mortality in the elderly worldwide. Influenza vaccination can prevent morbidity/mortality from influenza infection. A gap of 1-2 years, before an epidemic strain is recommended by the World Health Organization (WHO) to be the vaccine strain in Southeast Asia, has been reported; this results in a high rate of vaccine mismatch and excess influenza-associated morbidity. The aim of the current study was to evaluate the effect of repeated vaccination on vaccine effectiveness (VE) among the elderly in Taiwan, during years with and without early appearance of antigenically drifted strains.

methodsA historical cohort study was conducted to evaluate the impact of repeated vaccination on the reduction of influenza-associated hospitalization among persons older than 64 years over two influenza seasons: 2007-08, with all circulating virus strains mismatched, and 2008-09, with all virus strains matched with the vaccine strains, considering four exposure effects, namely current vaccine effect, sequential vaccination effect, residual protection effect and no vaccination effect. Propensity score matching on vaccination status was performed to ensure similar baseline characteristics between the groups that received and did not receive vaccination.

resultsOnly current-year vaccination in combination with prior history of annual revaccination significantly reduced the risk of hospitalization, with adjusted hazard ratios of 0.68 (95% CI: 0.54, 0.85) and 0.74 (95% CI: 0.57, 0.95) during the 2007-08 and 2008-09 influenza seasons, respectively. Further stratification showed that even during the 2007-08 influenza season, when all vaccinations were mismatched with the circulating strains, sequential vaccinations still significantly reduced influenza-associated hospitalization in the female population aged 68-74 and 75-84 years, with adjusted VE of 25.2% (95% CI: -9.6, 49.0%) and 36.9% (95% CI: 17.1, 52.0%), respectively.

conclusionOur study supports the recommendation of annual revaccination against influenza in the elderly, even though the circulating strain of influenza virus was antigenically mismatched with the vaccine strains.

Indexed as

AgedAged, 80 and overCohort StudiesFemaleHospitalizationHumansImmunization, SecondaryInfluenza, HumanInfluenza VaccinesMalePropensity ScoreResearch DesignSeasonsTaiwanVaccinationVaccine PotencyInfluenza Vaccineselderlyprior vaccination historypropensity score matchingrepeated vaccinationtrivalent influenza vaccinevaccine effectiveness

Identifiers

PMID32184579
PMCPMC7060795

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.