The study aims to investigate (1) if COVID-19 vaccine impacts on blood pressure, (2) theextent of impact on blood pressure (if any), and (3) which groups of subjects are moresusceptible to be affected by COVID-19 vaccine on blood
Coronavirus disease 19 (COVID-19), which is caused by severe acute respiratory syndrome
coronavirus-2 (SARS-CoV-2), has elicited global pandemic since January 2020. Until the
end of June 2021, the virus has caused 182 million confirmed COVID-19 cases and 3.95
million deaths worldwide. To stop the spread of virus, there has been rapid development
of vaccine against SARS-CoV-2. Currently there has been 9 vaccines authorized for
emergency use, and 8 vaccines received full approval for use in various countries.
Extensive studies have been showing the efficacy of different types of vaccines against
COVID-19 and its variants. Safety of COVID-19 vaccines has been a concern. Despite safety
profile of different vaccines demonstrated in phase 2/3 trials, there has been evolving
evidence on adverse effects of some particular COVID-19 vaccines. One of the mostly known
example is vaccine-induced thrombotic thrombocytopenia (VITT). Case series report4 and
observational studies on ChAdOx1 nCoV-19 vaccine showed high level of autoantibodies to
platelet factor-4 (PF4) which could contribute to microvascular damage, micro-bleeding
and platelet activation and therefore causes event of thrombosis. Apart from the
thrombotic risk of ChAdOx1 nCoV-19 vaccine, there has been studies providing the
preliminary data on effect of mRNA-based COVID-19 vaccine on blood pressure. Yet there
remains lack of evidence and detailed description on effect of COVID-19 vaccines and
blood pressure along the time. Given the vast population of hypertensive patients
worldwide, the increasing number of people being vaccinated and the importance of blood
pressure level to various human organs, it is essential to investigate the short- and
long-term effect of COVID-19 vaccine on blood pressure.
Inclusion Criteria:
- Subjects aged 18 years old or above
- Subjects with home blood pressure monitoring device
- Subjects with smartphone and with HealthCap application downloaded
- Subjects who understand Chinese to make an informed consent
Exclusion Criteria:
- Subjects unable to take regular home blood pressure measurement