COVID-19 Vaccines Reduce Risk of Cardiac, Thromboembolic Outcomes: Daily Dose

Patient Care brings primary care clinicians a lot of medical news every day—it’s easy to miss an important study. The Daily Dose provides a concise summary of one of the website's leading stories you may not have seen.


Last week, we reported on findings from a study published in Heart that examined the association between COVID-19 vaccination and the risk of post-COVID-19 cardiac and thromboembolic complications.

The study

Investigators conducted a staggered cohort study using electronic health records of 10.17 million vaccinated and 10.39 million unvaccinated individuals aged 18 years or older with no previous SARS-CoV-2 infection or COVID-19 vaccine at baseline based on national COVID-19 vaccination campaigns in the United Kingdom, Spain, and Estonia from January 2021 to July 2021.

Researchers used vaccination status as a time-varying exposure and included all COVID-19 vaccines approved within the study period: ChAdOx1 (Oxford/AstraZeneca), BNT162b2 (BioNTech/Pfizer), Ad26.COV2.S (Janssen), and mRNA-1273 (Moderna).

Outcomes included HF, VTE, and ATE recorded in 4 different time periods following SARS-CoV-2 infection: 0–30 days (acute phase), 31–90 days, 91–180 days, and 181–365 days (post-acute phase).

The findings

Results showed that COVID-19 vaccination was associated with reduced risks of post-COVID-19 cardiac and thromboembolic outcomes in the acute (0-30 days) and post-acute (31-365 days) phase, with the effect being stronger in the acute phase.

Investigators noted that the meta-analytic sHR for post-COVID VTE was 0.22 (95% CI, 0.17–0.29), ATE was 0.53 (95% CI, 0.44-0.63), and HF was 0.45 (95% CI, 0.38-0.53) for 0-30 days, while in the 91-180 days sHR were 0.53 (95% CI, 0.40-0.70), 0.72 (95% CI, 0.58-0.88), and 0.61 (95% CI, 0.51-0.73), respectively.

Authors' comment

"Findings from this study highlight yet another benefit of COVID-19 vaccination. However, further research is needed on the possible waning of the risk reduction over time and on the impact of booster vaccination."

Click here for more details.