Vaccination is associated with a lower risk of heart failure or hospitalization for a heart attack.

A flu shot can do more than keep you from having to spend a few days in bed.

An analysis of studies published Tuesday in the Journal of the American Medical Association confirms that the influenza vaccination is associated with a lower risk of heart failure or of hospitalization for a heart attack. The benefit is significantly greater for study participants with pre-existing coronary heart disease.

Dr. Jacob A. Udell, a cardiologist at the University of Toronto, and his colleagues reviewed six randomized clinical trials focused on whether flu shots help prevent cardiovascular episodes. Five of the studies were published; one was unpublished.

In the five published trials, 95 of 3,238 patients (2.9 percent) treated with influenza vaccine developed heart failure or had a heart attack, while 151 of 3,231 patients (4.7 percent) who did not get a flu shot had a heart attack or heart failure. Results of the unpublished study were similar at 2.9 percent and 4.6 percent, respectively, for those categories.

The meta-analysis highlights the greater benefit for patients with pre-existing coronary artery disease. The risk of a cardiovascular incident within 12 months was 10.3 percent for those individuals, if they’d had a flu shot, but was much higher, 23.1 percent for those in the group that did not get vaccinated against influenza. That amounts to a lowering of risk by 55 percent.

Respiratory tract infections caused by the flu may make the body more susceptible to cardiovascular events, according to the report.

Palm Beacher Chauncey Crandall, a cardiologist and author of The Simple Heart Cure: The 90-Day Program to Stop and Reverse Heart Disease, favors a preventive approach.

“Wash your hands when you have person-to-person contact, stay out of large gatherings and tight quarters,” Crandall said.

For heart health, Crandall encourages patients to take a multivitamin, stay well hydrated and eat a plant-based diet. Though not a “big advocate” of flu shots, he acknowledges that inflammation caused by influenza can put people with pre-existing heart conditions at risk for heart attacks.

The report by Udell and associates said several epidemiological studies have suggested there is a “strong inverse relationship” between vaccination for the flu and the risk of heart failure and heart attacks.