Flu Shots Protect Against Cardiovascular Events
Influenza is known to increase the risk of cardiovascular-related hospitalization and death. Now a meta-analysis of randomized, controlled trials (RCTs) and a large outcome trial confirm that receiving the yearly flu shot lowers these risks. Researchers identified six trials published between 2000 and 2021 that randomized 9,001 patients to the influenza vaccine or placebo and looked at the rates of major cardiovascular events and cardiovascular mortality in the following 12 months. Overall, 162 patients who received the flu vaccine (3.4%) experienced a cardiovascular event, as did 242 of those given the placebo (5.4%). Results were even stronger in patients who had recently suffered acute coronary syndrome, in which 6.5% of those vaccinated had an event, versus 11% of those on placebo. Only 1.7% of vaccinated patients died of cardiovascular causes, compared with 2.5% of patients on placebo. Flu season starts in November and can last into May. Experts recommend getting the flu shot in September or October for optimal protection (JAMA Network Open, April 1, 2022).
