Patients who receive the flu vaccine are less likely to experience a major adverse cardiovascular event, according to a meta-analysis of randomized clinical trials (RCTs) conducted by Canadian researchers.

The greatest treatment effect was seen among the highest-risk patients with more active coronary disease, according to researchers.

“Within this global meta-analysis of RCTs that studied patients with high cardiovascular risk, influenza vaccination was associated with a lower risk of major adverse cardiovascular events within 1 year,” the authors concluded. “Influenza vaccination was particularly associated with cardiovascular prevention in patients with recent ACS [acute coronary syndrome].”

Researchers identified five published and one unpublished RCTs that satisfied inclusion criteria. Analyses were stratified by subgroups of patients with and without a history of acute coronary syndrome within 1 year of randomization.

The authors noted the need for “future research with an adequately powered multicenter trial to confirm the efficacy of this low-cost, annual, safe, easily administered, and well-tolerated therapy to reduce cardiovascular risk beyond current therapies is warranted.”