One of the ongoing concerns regarding the novel coronavirus disease (COVID-19) vaccine is reports of thromboembolism and cardiovascular events. There have been reports of blood clots following adenovirus-based COVID-19 vaccination, and the association was further evaluated in an observational study. Subsequently, mRNA-based vaccines were found to be associated with a risk of rare myocarditis events.

Contrary to these past associations, new research published in the journal heart, the risk of venous thromboembolism (VTE), arterial thrombosis/thromboembolism (ATE), thromboembolic and cardiac events in heart failure (HF) after acute COVID-19 infection in patients with the following conditions: reported a significant decrease (45-81%). I received the vaccination.

“Vaccination against SARS-CoV-2 may reduce acute thromboembolic and cardiac complications following COVID-19 infection, possibly by reducing the risk of SARS-CoV-2 infection and the severity of COVID-19 disease with the vaccine.” “induced immunity,” the study authors wrote.

Study parameters and results
Researchers conducted a time-lagged cohort study based on national vaccination campaigns using EHRs in the United Kingdom, Spain, and Estonia. The vaccine rollout was grouped into four phases with predetermined enrollment periods. The study included 10.17 million vaccinated people and 10.39 million unvaccinated people.

Each tier included all individuals eligible for vaccination without a history of COVID-19 infection or vaccination on the start date. Vaccination status was used as a time-varying exposure. Outcomes include his three adverse events mentioned above: HF, VTE, and ATE. He has four periods after infection: 0-30, 31-90, 91-180, and 181-365 days.

The vaccines used in this study were approved within the study period from January 2021 to July 2021, including ChAdOx1 (Oxford/AstraZeneca), BNT162b2 (Pfizer-BioNTech) Ad26.COV2.S (Janssen). Ta. and mRNA-1273 (Moderna).

VTE:
“Reduced risk associated with vaccination is observed for acute and post-acute VTE, DVT, and PE. Acute meta-analysis sHR 0.22 (95% CI, 0.17 to 0.29). 0.36 (0.28–0.45) for post-acute VTE, the sHR estimates for 31-90 days, 91-180 days, and 181-365 days after COVID-19 infection were 0.43 (0.34-0.25), respectively; 0.53), 0.53 (0.40 to 0.70), and 0.50 (0.36 to 0.70), respectively,” the investigators reported.

ate:
“Similarly, the risks of ATE, IS, and MI during the acute phase after infection were reduced in the vaccinated group with sHR of 0.53 (0.44–0.63), 0.55 (0.43–0.70), and 0.49 (0.38–0.62), respectively. The reduced risk associated with vaccination persisted after acute ATE, with sHRs of 0.74 (0.60 to 0.92), 0.72 (0.58 to 0.88), and 31 to 90 days, 91 to 180 days, and 181 to 365 days after vaccination. 0.62 (0.48 to 0.80), respectively, for COVID-19,” they wrote.

HF:
“Acute phase meta-analysis estimates showed that the sHR for heart failure was 0.45 (0.38-0.53), MP was 0.41 (0.26-0.66), and VACA was 0.41 (0.27-0.63). The reduced risk persisted in heart failure after (COVID-19): sHR 0.61 (0.51-0.73) for 31-90 days, 0.61 (0.51-0.73) for 91-180 days, and 0.52 (0.43) for 181-365 days. ~0.63),” the researchers noted. “For post-acute MP, the risk decreased only in the first post-acute period (31–90 days), with an sHR of 0.43 (0.21–0.85). did not show any association with HS.

Vaccine validity period
Regarding the vaccine’s benefits against VTE, ATE, and heart failure, the researchers said that protection against these events lasts up to a year. Although other complications were not clear.

The researchers also noted that new studies are needed to determine not only the impact of booster vaccinations, but also whether the risk reduction may wane over time.

reference
Mercade-Besola N, Li X, Korde R, et al. Role of novel coronavirus vaccines in preventing thromboembolic and cardiovascular complications after COVID-19 infection. heart. Published online March 12, 2024. doi:10.1136/heartjnl-2023-323483