Short-term safety of COVID-19 mRNA vaccines with respect to all-cause mortality in the older population in Norway. Issue 2 (9th January 2023)

• Record Type: Journal Article
• Authors: Lopez-Doriga Ruiz, Paz; Gunnes, Nina; Michael Gran, Jon; Karlstad, Øystein; Selmer, Randi; Dahl, Jesper; Bøås, Håkon; Aubrey White, Richard; Christine Hofman, Aurora; Hessevik Paulsen, Trine; Viksmoen Watle, Sara; Hylen Ranhoff, Anette; Bukholm, Geir; Løvdal Gulseth, Hanne; Tapia, German
• Is Part Of: Vaccine. Volume 41:Issue 2(2023)
• Page Start: 323
• Page End: 332
• Publication Date: 2023-01-09
• Subjects: COVID-19 vaccine -- Side-effects -- Elderly; Vaccines -- Periodicals; 615.372
• DOI: 10.1016/j.vaccine.2022.10.085
• Languages: English
• ISSNs: 0264-410X

Abstract

Highlights: Frail older individuals are not included in clinical trials of COVID-19 vaccination. Previous studies have shown few local and systemic reactions among vaccinated older people; however, even mild adverse events following immunization could destabilize frail individuals. There was no evidence of increased short-term mortality among vaccinated older individuals. Short-term mortality was lower in the vaccinated group compared to the unvaccinated group, which could reflect a healthy-vaccinee effect. Real-world studies give the possibility to monitor adverse effects of COVID-19 vaccination. Abstract: Background: There have been concerns about COVID-19 vaccination safety among frail older individuals. We investigated the relationship between COVID-19 mRNA vaccination and mortality among individuals aged ≥ 70 years and whether mortality varies across four groups of health services used. Methods: In this nationwide cohort study, we included 688, 152 individuals aged ≥ 70 years at the start of the Norwegian vaccination campaign (December 27, 2020). We collected individual-level data from the Norwegian Emergency Preparedness Register for COVID-19. Vaccinated and unvaccinated individuals were matched (1:1 ratio) on the date of vaccination based on sociodemographic and clinical characteristics. The main outcome was all-cause mortality during 21 days after first dose of COVID-19 mRNA vaccination. Kaplan-Meier survival functions were estimated for the vaccinated and unvaccinated groups. We used Cox proportional-hazards regression to estimate hazard ratios (HRs) of death between vaccinated and unvaccinated individuals, with associated 95% confidence intervals (CIs), overall and by use of health services (none, home-based, short- and long-term nursing homes) and age group. Results: Between December 27, 2020, and March 31, 2021, 420, 771 older individuals (61.1%) were vaccinated against COVID-19. The Kaplan-Meier estimates based on the matched study sample showed a small absolute risk difference in all-cause mortality between vaccinated and unvaccinated individuals, with a lower mortality in the vaccinated group (overall HR 0.28 [95% CI: 0.24–0.31]). Similar results were obtained in analyses stratified by use of health services and age group. Conclusion: We found no evidence of increased short-term mortality among vaccinated individuals in the older population after matching on sociodemographic and clinical characteristics affecting vaccination and mortality.