Cardioprotective effects of influenza vaccination among patients with established cardiovascular disease or at high cardiovascular risk: a systematic review and meta-analysis

Abstract

Background The clinical impact of the influenza vaccination on cardiovascular outcomes in people with established cardiovascular disease (CVD) is still debated. Aim The aim of this meta-analysis was to estimate the effect of influenza vaccination on cardiovascular and cerebrovascular outcomes among patients with established CVD. Methods We systematically searched all electronic databases from inception until 15 April 2022. Primary clinical outcomes were all-cause mortality (ACM), and major adverse clinical events (MACE). Secondary endpoints were heart failure, myocardial infarction, CV mortality, and stroke. Results Eighteen articles (five randomized trials and thirteen observational studies), with a total of 22,532,165 patients were included in the analysis. There were 217,072 participants included in the high cardiovascular risk or established CVD population (vaccinated n = 111,073 and unvaccinated n = 105,999). The mean age of the patients was 68 years old, without any difference between groups (69 vs 71) years. At mean follow-up of 1.5 years, vaccinated group was associated with lower risk for all-cause mortality [HR, 0.71(95%CI, 0.63-0.80), p < 0.001], MACE [HR, 0.83(95%CI:0.72-0.96), p = 0.01], CV mortality [HR, 0.78(95%CI:0.68-0.90), p < 0.001] and myocardial infarction [HR, 0.82(95%CI:0.74-0.92), p < 0.001] compared to unvaccinated group. While incidence of stroke [HR, 1.03 (95%CI, 0.92-1.06), p = 0.61] and heart failure [HR, 0.74 (95%CI, 0.51-1.08), p = 0.12] did not differ between the two groups. Conclusion Influenza vaccination reduced major adverse clinical events, all-cause mortality, CV mortality and myocardial infarction. These highlighted the importance of influenza vaccination in established CVD or high cardiovascular risk.

Comparison of outcome among type 2 vs type 1 myocardial infarction: a systematic review and meta-analysis

“…This meta-analysis was conducted and reported following the Cochrane and preferred reporting items for systematic review and meta-analysis (PRISMA) 2020 guidelines and performed according to the established methods, as described previously. [8][9][10] The pre-specified study protocol has been registered in the PROSPERO (CRD42022310355).…”

Association between nonalcoholic fatty liver disease and atrial fibrillation and other clinical outcomes: a meta-analysis

“…This meta-analysis was conducted and reported following the Cochrane and PRISMA (preferred reporting items for systematic review and meta-analysis) 2020 guidelines and performed according to established methods, as described previously. [18][19][20][21] The prespecified study protocol has been registered in the PROSPERO (CRD42022357336).…”

Monkeypox-Induced Myocarditis: A Systematic Review

“…This systematic review was conducted and reported in conformity with the Cochrane and PRISMA (Preferred reporting items for systematic review and Meta-analysis) 2020 guidelines as described previously 10 , 11 , 12 . The pre-specified protocol has been registered on Prospero ( CRD42023388476 ).…”