Dataset Information

Risk factors for COVID-19 hospitalization after COVID-19 vaccination: a population-based cohort study in Canada.

ABSTRACT:

Objectives

With the uptake of COVID-19 vaccines, there is a need for population-based studies to assess risk factors for COVID-19-related hospitalization after vaccination and how they differ from unvaccinated individuals.

Methods

We used data from the British Columbia COVID-19 Cohort, a population-based cohort that includes all individuals (aged ≥18 years) who tested positive for SARS-CoV-2 by real-time reverse transcription-polymerase chain reaction from January 1, 2021 (after the start of vaccination program) to December 31, 2021. We used multivariable logistic regression models to assess COVID-19-related hospitalization risk by vaccination status and age group among confirmed COVID-19 cases.

Results

Of the 162,509 COVID-19 cases included in the analysis, 8,546 (5.3%) required hospitalization. Among vaccinated individuals, an increased odds of hospitalization with increasing age was observed for older age groups, namely those aged 50-59 years (odds ratio [OR] = 2.95, 95% confidence interval [CI]: 2.01-4.33), 60-69 years (OR = 4.82, 95% CI: 3.29, 7.07), 70-79 years (OR = 11.92, 95% CI: 8.02, 17.71), and ≥80 years (OR = 24.25, 95% CI: 16.02, 36.71). However, among unvaccinated individuals, there was a graded increase in odds of hospitalization with increasing age, starting at age group 30-39 years (OR = 2.14, 95% CI: 1.90, 2.41) to ≥80 years (OR = 41.95, 95% CI: 35.43, 49.67). Also, comparing all the age groups to the youngest, the observed magnitude of association was much higher among unvaccinated individuals than vaccinated ones.

Conclusion

Alongside a number of comorbidities, our findings showed a strong association between age and COVID-19-related hospitalization, regardless of vaccination status. However, age-related hospitalization risk was reduced two-fold by vaccination, highlighting the need for vaccination in reducing the risk of severe disease and subsequent COVID-19-related hospitalization across all population groups.

SUBMITTER: Velasquez Garcia HA

PROVIDER: S-EPMC9731811 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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Publications

Risk factors for COVID-19 hospitalization after COVID-19 vaccination: a population-based cohort study in Canada.

Velásquez García Héctor A HA Adu Prince A PA Harrigan Sean S Wilton James J Rasali Drona D Binka Mawuena M Sbihi Hind H Smolina Kate K Janjua Naveed Z NZ

International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases 20221209

<h4>Objectives</h4>With the uptake of COVID-19 vaccines, there is a need for population-based studies to assess risk factors for COVID-19-related hospitalization after vaccination and how they differ from unvaccinated individuals.<h4>Methods</h4>We used data from the British Columbia COVID-19 Cohort, a population-based cohort that includes all individuals (aged ≥18 years) who tested positive for SARS-CoV-2 by real-time reverse transcription-polymerase chain reaction from January 1, 2021 (after t ...[more]

PMID: 36503044

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Dataset Information

Risk factors for COVID-19 hospitalization after COVID-19 vaccination: a population-based cohort study in Canada.

Objectives

Methods

Results

Conclusion

Publications

Risk factors for COVID-19 hospitalization after COVID-19 vaccination: a population-based cohort study in Canada.

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