Changes in haemostasis and inflammatory markers after mRNA BNT162b2 and vector Ad26.CoV2.S SARS-CoV-2 vaccination

Introduction: Reported thromboembolic events after SARS-CoV-2 vaccinations are still raising concerns, predominantly in non-scientific population. The aim of our study was to investigate the differences between haemostasis and inflammatory markers in the subjects vaccinated with mRNA BNT162b2 and vector Ad26.CoV2.S vaccine.Materials and methods: The study included 87 subjects vaccinated with mRNA BNT162b2 and 84 with Ad26. CoV2.S vaccine. All the laboratory parameters (TAT, F 1 + 2, IL-6, CRP, big endothelin-1, platelets, fibrinogen, Ddimers, VWF activity) were investigated for the mRNA vaccine at five (before the first dose, 7 and 14 days after the first and second vaccine dose), and three time points (before the first dose, 7 and 14 days after) for the vector vaccine, respectively. All the markers were measured by well-established laboratory methods. Results: Our results have shown statistically higher CRP levels in the vector group 7 days after vaccination (P = 0.014). Furthermore, study has revealed statistically significant rise in D-dimers (P = 0.004) between tested time points in both vaccine groups but without clinical repercussions.Conclusion: Although statistically significant changes in haemostasis markers have been obtained, they remained clinically irrelevant. Thus, our study implicates that there is no plausible scientific evidence of a significant disruption in the coagulation and inflammatory processes after vaccination with BNT162b2 mRNA and Ad26. CoV2.S vector SARS-CoV-2 vaccines.

Automated summary

This study investigated the differences in haemostasis and inflammatory markers in subjects vaccinated with mRNA BNT162b2 and Ad26.CoV2.S vaccines. The results showed a statistically significant increase in CRP levels in the vector group after 7 days of vaccination. Additionally, both vaccine groups had a significant rise in D-dimers between the tested time points, but without clinical implications. Therefore, vaccination with BNT162b2 mRNA and Ad26.CoV2.S vaccines did not significantly disrupt coagulation and inflammatory processes.