Influenza vaccination is related to considerably decrease odds of myocardial infarction (MI), in response to a big meta-analysis printed late final week in BMC Public Well being.
Within the research, researchers led by a crew from Zhejiang Chinese language Medical College in Hangzhou, China, gathered information from 15 observational research, together with seven cohort research, seven case-control research, and one self-controlled case collection. Collectively, the research concerned 23.5 million individuals. Most contributors have been older adults, starting from roughly 57 to 77 years.
In analyzing the pooled information, the researchers discovered flu vaccination was related to an 18% discount (vary on the 95% confidence interval, 14% to 22%) within the odds of MI in contrast with unvaccinated controls.
Constant hyperlink throughout research, affected person teams
Subgroup analyses of the information discovered a constant hyperlink between the flu vaccine and decrease odds of coronary heart assault throughout various kinds of research and affected person teams. When the crew checked out age-stratified outcomes, they discovered that vaccinated individuals 70 and older and people 70 and youthful had comparably decrease threat of coronary heart assault. The identical detrimental affiliation held true for many who had beforehand had a coronary heart assault in contrast with those that had not. The flu vaccine was related to decrease odds of MI in each cohort and case-control research.
Coronary heart assaults are typically extra frequent throughout flu season, notice the authors, suggesting that viral infections might set off systemic irritation and lift the danger of cardiovascular occasions.
“Influenza vaccination may doubtlessly cut back the danger of MI by assuaging the systemic irritation and endothelial dysfunction related to an infection,” the authors write.
The evaluation had some limitations. All included research have been observational and therefore can’t set up causality, and flu vaccination was broadly outlined, so data on the frequency and timing of vaccination was restricted.
Nonetheless, “this meta-analysis signifies that influenza vaccination is related to decrease odds of myocardial infarction,” write the authors, who known as for future research to “make clear the underlying mechanisms and to refine the understanding of this affiliation in up to date populations.”
