A recent study highlights the close association between influenza infections and an increased risk of atherothrombotic events, including the acute myocardial infarction (heart attack) and ischemic stroke. The key findings of this study were published in the recent edition of The Journal of Infectious Diseases.
This study utilized a population-based self-controlled case series design and drew individual-level data sourced from electronic registries in the Spain. This study encompassed over 2 million individuals and examined the correlation between influenza infections diagnosed in primary care settings with laboratory-confirmed cases in hospitals with subsequent atherothrombotic events.

The results revealed a sharp increase in the risk of such events among individuals aged 50 years and above in the two weeks following even mild influenza cases. Those with fewer pre-existing risk factors saw their risk double, while the individuals with severe cases faced more than a fourfold increase in risk and persisted at more than twice the baseline risk for up to two months post-infection.
Through meticulous sensitivity analyses, the findings provided compelling evidence that support a causal relationship between influenza infection and atherothrombotic events. This transient yet substantial increase in the risk following influenza infection underlines the need for more vigilant and cautious preventive measures among the high-risk groups.
These findings of this research should reinforce the existing recommendations for influenza prevention, particularly among at-risk populations. The findings of this research highlights the critical importance of influenza prevention efforts in older adults and those with pre-existing health conditions. The relationship between influenza infection and the increased risk of heart attacks and strokes mandates proactive measures to reduce the impact of seasonal influenza.
Source:
Muñoz-Quiles, C., López-Lacort, M., Urchueguía, A., Díez-Domingo, J., & Orrico-Sánchez, A. (2024). Risk of cardiovascular events after influenza: A population-based Self Controlled Case Series study, Spain 2011-2018. In The Journal of Infectious Diseases. Oxford University Press (OUP). https://doi.org/10.1093/infdis/jiae070