Objective: To investigate the association between COVID-19 vaccination and increased blood pressure outcomes, including hypertension, and to identify potential risk factors in the adult vaccinated population. Design and method: A systematic review was conducted according to PRISMA guidelines. Six databases were searched using: (“COVID-19” OR “SARS-CoV-2”) AND vaccin* AND hypertensi* AND “blood pressure”. Studies published between 8th December 2020 and 22nd October 2024 involving adults 18 years or older with at least one dose of any COVID-19 vaccine and blood pressure measurement after vaccination were included. Non-English language, strictly descriptive studies, and secondary literature were excluded. Risk of bias was assessed using Cochrane ROBINS-I and RoB 2.0. Data were synthesised narratively because heterogeneity and incomplete reporting precluded meta-analysis. Results: Twenty-four studies (8,836,143 participants) were included. Twelve studies assessed hypertension after COVID-19 vaccination, with three reporting an association. Malignant hypertension was examined in two studies, both of which reported an association. Sixteen studies evaluated blood pressure changes post-vaccination, with four reporting increases. Reports of increased blood pressure were more frequent following Pfizer-BioNTech than AstraZeneca vaccination. Older age, female sex, and prior COVID-19 infection were identified as potential risk factors. No studies were judged to be at low risk of bias. Conclusions: A potential association between COVID-19 vaccines and increased blood pressure outcomes may exist, although evidence is insufficient to establish causation. Findings are inconclusive due to studies’ inconsistent definitions, imprecise reporting, and high risk of bias. Larger prospective studies with robust methods, adequate confounder adjustment, and follow-up are warranted to improve vaccine monitoring and manage blood pressure rises post-vaccination.
Houston et al. (2026) studied this question.