Goals
Concerns about the cardiovascular safety of coronavirus disease 2019 (COVID-19) vaccines among people with cardiovascular disease (CVD) may raise vaccine hesitancy. We sought to evaluate the association between two COVID-19 vaccines, BNT162b2 and CoronaVac, and the risk of major adverse cardiovascular events (MACE) in people with established CVD.
Methods and results
We identified individuals with a history of CVD before February 23, 2021 and a diagnosis of MACE between February 23, 2021 and January 31, 2022 in Hong Kong. MACE was defined as a composite of myocardial infarction, stroke, revascularization, and cardiovascular death. Electronic health records from the Hong Kong Hospital Authority were linked to vaccination records from the Department of Health.
A self-controlled case series approach was used to assess the risk of MACE for 0 to 13 and 14 to 27 days after two doses of the COVID-19 vaccine. We calculated incidence rate ratios (IRRs) to compare the risk of MACE between each risk period and the reference period.
A total of 229,235 individuals with CVD were identified, of which 1764 were vaccinated and diagnosed with MACE during the observation period (BNT162b2 = 662; CoronaVac = 1102).
For BNT162b2, the IRRs were 0.48 [95% confidence interval (CI) 0.23–1.02] for the first dose and 0.87 (95% CI 0.50–1.52) for the second dose during the risk period of 0 to 13 days, 0.40 (95% CI 0.18-0.93) for the first dose and 1.13 (95% CI 0.70-1.84) for the second dose during the risk period of 14-27 days.
For CoronaVac, the IRRs were 0.43 (95% CI 0.24–0.75) for the first dose and 0.73 (95% CI 0.46–1.16) for the second dose during the risk period from 0 to 13 days, 0.54 (95% CI 0.33–0.90) for the first dose and 0.83 (95% CI 0.54–1.29) for the second dose during the risk period from 14 to 27 days.
Consistent results were found in subgroup analyzes for different sexes, age groups, and different underlying cardiovascular conditions.
Conclusion
Our findings showed no evidence of an increased risk of MACE after vaccination with BNT162b2 or CoronaVac in patients with CVD. Future research is required to monitor risk after the third dose of each vaccine.
Comments
COVID-19 vaccination is not associated with an increased risk of heart attack or stroke in patients with established cardiovascular disease, according to a large study published in Cardiovascular Research , a journal of the European Society of Cardiology (ESC).
“Our study showed that pre-existing cardiovascular disease should not prevent people from getting vaccinated against COVID-19,” said study author Dr. Esther W. Chan of the University of Li Ka Shing School of Medicine. Hong Kong, Hong Kong Special. Administrative Region, China. “Vaccination is particularly important for this group, as cardiovascular disease is associated with worse outcomes and a higher risk of death after COVID-19 infection.”
This was the first study to examine the association between COVID-19 vaccines and the risk of major adverse cardiovascular events (MACE) in patients with cardiovascular disease. The study focused on BNT162b2 and CoronaVac, the only COVID-19 vaccines authorized for emergency use in Hong Kong.
The researchers linked data from electronic health records managed by the Hong Kong Hospital Authority, which covers about 80% of hospital admissions, and vaccination records provided by the Hong Kong Department of Health. The first two vaccine doses were included in the analyses. People were not allowed to switch between vaccine types for the first two doses.
The researchers identified patients with existing cardiovascular disease and a new diagnosis of MACE between February 23, 2021, when the mass COVID-19 vaccination program began in Hong Kong, and January 31, 2022. Established cardiovascular disease It included coronary heart disease, cerebrovascular disease, peripheral vascular disease, and prior interventions such as stenting. MACE included myocardial infarction, stroke, revascularization, or cardiovascular death.
The researchers used the self-controlled case series study design, which was developed to evaluate the risk of adverse events after vaccination. Each patient’s MACE risk was compared to themselves up to 27 days after each vaccine dose (exposure period) versus the non-exposure baseline period.
Dr Chan explained: “A traditional cohort study would compare the vaccinated group with the unvaccinated group, but the two groups could have different baseline characteristics. A self-controlled case series avoids the issue of differences between groups since each individual acts as his or her own control.”
A total of 229,235 patients with cardiovascular disease were identified, of whom 1,764 were vaccinated and experienced MACE during the study period (662 received BNT162b2 and 1,102 received CoronaVac). For BNT162b2 and CoronaVac, the researchers calculated incidence rate ratios (IRRs) to compare the risk of MACE during the 13 days after vaccination compared to the baseline period.
IRRs were also calculated for the risk of MACE during days 14 to 27 post-vaccination compared with the baseline period. Analyzes were performed for the first and second doses.
There was no evidence of an increased risk of MACE after the first or second dose of BNT162b2 or CoronaVac. For the first dose of BNT162b2, the IRRs were 0.48 (95% confidence interval [CI], 0.23–1.02) for the first 13 days after vaccination and 0.40 (95% CI: 95%: 0.18–0.93) during days 14 to 27 after vaccination.
For the second dose, the IRRs were 0.87 (95% CI 0.50–1.52) for the first 13 days and 1.13 (95% CI 0.70–1.84) for the 14th day. to 27 after vaccination.
For the first dose of CoronaVac, the IRRs were 0.43 (95% CI 0.24–0.75) for the first 13 days and 0.54 (95% CI 0.33–0.90) for the first 13 days. days 14 to 27 after vaccination. For the second dose, the IRRs were 0.73 (95% CI 0.46–1.16) for the first 13 days and 0.83 (95% CI 0.54–1.29) for days 14–27. after vaccination.
Dr Chan said: “The findings were consistent for women and men, people under and over 65 years of age and patients with different underlying cardiovascular conditions. "The results should provide reassurance about the cardiovascular safety of these two vaccines."
