Rapid Review Quiz: Unusual Vaccine News

Michael Stuart Bronze, MD


February 13, 2023

Investigators conducting a recent systematic review and meta-analysis searched the PubMed, Embase, and Cochrane Library databases to identify studies published through October 25, 2021 that investigated the possible effects of the influenza vaccine on arrhythmia risk. They included one randomized controlled trial with 2532 patients and six observational studies with a little more than 3 million patients.

The randomized controlled trial demonstrated a nonsignificant benefit of the influenza vaccine against arrhythmias (odds ratio [OR], 0.43; 95% CI, 0.11-1.64; P = .20) in patients after myocardial infarction or with high-risk stable coronary heart disease.

A meta-analysis of the observational studies revealed that influenza vaccination was associated with a significantly lower risk for arrhythmia (OR, 0.82; 95% CI, 0.70-0.97; P = .02; I2 = 76%). Subgroup analysis indicated that influenza vaccination was associated with a decreased risk for atrial fibrillation (OR, 0.94; 95% CI, 0.90-0.98; P = .006; I2 = 0%) and a nonsignificant but positive trend concerning ventricular arrhythmias (OR, 0.68; 95% CI, 0.42-1.11; P = .12; I2 = 85%). The researchers concluded that influenza vaccination may reduce the risk for arrhythmia, especially atrial fibrillation.

Learn more about atrial fibrillation.


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