As influenza is significantly associated with an increased risk of new-onset atrial fibrillation (AF), the findings of a recent study indicate that the risk could be reduced through influenza vaccination. Researchers in Taiwan aimed to investigate whether influenza infection is a risk factor for AF and if influenza vaccination could reduce the risk. The research team identified more than 11,000 patients with newly diagnosed AF from the Taiwan National Health Insurance Research Database records for 2000 to 2010. Each patient was matched with four control patients without AF who were enrolled on the same date, which brought the total number of patients in the study to about 57,000.
The patients who did not get influenza and had not been vaccinated served as a reference group. An analysis of the data showed that patients diagnosed with an influenza infection and who had not been vaccinated had an 18% higher risk of AF than patients in the reference group. Also, patients who had been vaccinated and experienced influenza had a similar risk of AF to patients in the reference group. Overall, influenza vaccination was consistently associated with a lower risk of AF in different groups of patients, according to a Science Daily news report.
“According to the findings presented here, the possibility of AF should be kept in mind when patients with influenza infection complain of palpitations or experience ischemic stroke,” the researchers write. “Influenza vaccination should be encouraged for patients, especially those who have a high risk of atrial fibrillation, to try to prevent the occurrence of atrial fibrillation and subsequent stroke. However, a further prospective study is necessary to confirm our findings.”
In an accompanying editorial, Nishant Verma, MD, MPH, and Bradley P. Knight, MD, FHRS, state that this study suggests there are more possible public health benefits of the vaccine. Verma and Knight write, “The results of this study beg the question as to whether the acute treatment of the influenza infection itself, or addressing the inflammatory response associated with infection, may help prevent secondary episodes of AF. Beyond the prospective trial mentioned by the authors, we look forward to future studies into these and other areas that may help confirm and validate the observed findings.”
Source: Science Daily